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Implement sharable row-level locks, and use them for foreign key references 

to eliminate unnecessary deadlocks.  This commit adds SELECT ... FOR SHARE
paralleling SELECT ... FOR UPDATE.  The implementation uses a new SLRU
data structure (managed much like pg_subtrans) to represent multiple-
transaction-ID sets.  When more than one transaction is holding a shared
lock on a particular row, we create a MultiXactId representing that set
of transactions and store its ID in the row's XMAX.  This scheme allows
an effectively unlimited number of row locks, just as we did before,
while not costing any extra overhead except when a shared lock actually
has to be shared.   Still TODO: use the regular lock manager to control
the grant order when multiple backends are waiting for a row lock.

Alvaro Herrera and Tom Lane.
This commit is contained in:
Tom Lane 2005-04-28 21:47:18 +00:00
parent d902e7d63b
commit bedb78d386
55 changed files with 2802 additions and 439 deletions
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72
doc/src/sgml/mvcc.sgml
View File

@ -1,5 +1,5 @@
<!--
$PostgreSQL: pgsql/doc/src/sgml/mvcc.sgml,v 2.49 2005/03/24 00:03:18 neilc Exp $
$PostgreSQL: pgsql/doc/src/sgml/mvcc.sgml,v 2.50 2005/04/28 21:47:09 tgl Exp $
-->
<chapter id="mvcc">
@ -253,11 +253,12 @@ $PostgreSQL: pgsql/doc/src/sgml/mvcc.sgml,v 2.49 2005/03/24 00:03:18 neilc Exp $
</para>
<para>
<command>UPDATE</command>, <command>DELETE</command>, and <command>SELECT
FOR UPDATE</command> commands behave the same as <command>SELECT</command>
<command>UPDATE</command>, <command>DELETE</command>, <command>SELECT
FOR UPDATE</command>, and <command>SELECT FOR SHARE</command> commands
behave the same as <command>SELECT</command>
in terms of searching for target rows: they will only find target rows
that were committed as of the command start time. However, such a target
row may have already been updated (or deleted or marked for update) by
row may have already been updated (or deleted or locked) by
another concurrent transaction by the time it is found. In this case, the
would-be updater will wait for the first updating transaction to commit or
roll back (if it is still in progress). If the first updater rolls back,
@ -268,7 +269,10 @@ $PostgreSQL: pgsql/doc/src/sgml/mvcc.sgml,v 2.49 2005/03/24 00:03:18 neilc Exp $
the row. The search condition of the command (the <literal>WHERE</> clause) is
re-evaluated to see if the updated version of the row still matches the
search condition. If so, the second updater proceeds with its operation,
starting from the updated version of the row.
starting from the updated version of the row. (In the case of
<command>SELECT FOR UPDATE</command> and <command>SELECT FOR
SHARE</command>, that means it is the updated version of the row that is
locked and returned to the client.)
</para>
<para>
@ -346,25 +350,26 @@ COMMIT;
</para>
<para>
<command>UPDATE</command>, <command>DELETE</command>, and <command>SELECT
FOR UPDATE</command> commands behave the same as <command>SELECT</command>
<command>UPDATE</command>, <command>DELETE</command>, <command>SELECT
FOR UPDATE</command>, and <command>SELECT FOR SHARE</command> commands
behave the same as <command>SELECT</command>
in terms of searching for target rows: they will only find target rows
that were committed as of the transaction start time. However, such a
target
row may have already been updated (or deleted or marked for update) by
row may have already been updated (or deleted or locked) by
another concurrent transaction by the time it is found. In this case, the
serializable transaction will wait for the first updating transaction to commit or
roll back (if it is still in progress). If the first updater rolls back,
then its effects are negated and the serializable transaction can proceed
with updating the originally found row. But if the first updater commits
(and actually updated or deleted the row, not just selected it for update)
(and actually updated or deleted the row, not just locked it)
then the serializable transaction will be rolled back with the message
<screen>
ERROR: could not serialize access due to concurrent update
</screen>
because a serializable transaction cannot modify rows changed by
because a serializable transaction cannot modify or lock rows changed by
other transactions after the serializable transaction began.
</para>
@ -571,10 +576,12 @@ SELECT SUM(value) FROM mytab WHERE class = 2;
</para>
<para>
The <command>SELECT FOR UPDATE</command> command acquires a
The <command>SELECT FOR UPDATE</command> and
<command>SELECT FOR SHARE</command> commands acquire a
lock of this mode on the target table(s) (in addition to
<literal>ACCESS SHARE</literal> locks on any other tables
that are referenced but not selected <option>FOR UPDATE</option>).
that are referenced but not selected
<option>FOR UPDATE/FOR SHARE</option>).
</para>
</listitem>
</varlistentry>
@ -714,7 +721,7 @@ SELECT SUM(value) FROM mytab WHERE class = 2;
<tip>
<para>
Only an <literal>ACCESS EXCLUSIVE</literal> lock blocks a
<command>SELECT</command> (without <option>FOR UPDATE</option>)
<command>SELECT</command> (without <option>FOR UPDATE/SHARE</option>)
statement.
</para>
</tip>
@ -725,25 +732,37 @@ SELECT SUM(value) FROM mytab WHERE class = 2;
<title>Row-Level Locks</title>
<para>
In addition to table-level locks, there are row-level locks.
A row-level lock on a specific row is automatically acquired when the
row is updated (or deleted or marked for update). The lock is held
until the transaction commits or rolls back.
Row-level locks do not affect data
querying; they block <emphasis>writers to the same row</emphasis>
only. To acquire a row-level lock on a row without actually
In addition to table-level locks, there are row-level locks, which
can be exclusive or shared locks. An exclusive row-level lock on a
specific row is automatically acquired when the row is updated or
deleted. The lock is held until the transaction commits or rolls
back. Row-level locks do not affect data querying; they block
<emphasis>writers to the same row</emphasis> only.
</para>
<para>
To acquire an exclusive row-level lock on a row without actually
modifying the row, select the row with <command>SELECT FOR
UPDATE</command>. Note that once a particular row-level lock is
acquired, the transaction may update the row multiple times without
UPDATE</command>. Note that once the row-level lock is acquired,
the transaction may update the row multiple times without
fear of conflicts.
</para>
<para>
To acquire a shared row-level lock on a row, select the row with
<command>SELECT FOR SHARE</command>. A shared lock does not prevent
other transactions from acquiring the same shared lock. However,
no transaction is allowed to update, delete, or exclusively lock a
row on which any other transaction holds a shared lock. Any attempt
to do so will block until the shared locks have been released.
</para>
<para>
<productname>PostgreSQL</productname> doesn't remember any
information about modified rows in memory, so it has no limit to
the number of rows locked at one time. However, locking a row
may cause a disk write; thus, for example, <command>SELECT FOR
UPDATE</command> will modify selected rows to mark them and so
UPDATE</command> will modify selected rows to mark them locked, and so
will result in disk writes.
</para>
@ -873,9 +892,10 @@ UPDATE accounts SET balance = balance - 100.00 WHERE acctnum = 22222;
<para>
To ensure the current validity of a row and protect it against
concurrent updates one must use <command>SELECT FOR
UPDATE</command> or an appropriate <command>LOCK TABLE</command>
statement. (<command>SELECT FOR UPDATE</command> locks just the
concurrent updates one must use <command>SELECT FOR UPDATE</command>,
<command>SELECT FOR SHARE</command>, or an appropriate <command>LOCK
TABLE</command> statement. (<command>SELECT FOR UPDATE</command>
or <command>SELECT FOR SHARE</command> locks just the
returned rows against concurrent updates, while <command>LOCK
TABLE</command> locks the whole table.) This should be taken into
account when porting applications to

9
doc/src/sgml/ref/grant.sgml
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@ -1,5 +1,5 @@
<!--
$PostgreSQL: pgsql/doc/src/sgml/ref/grant.sgml,v 1.45 2005/01/22 23:22:18 momjian Exp $
$PostgreSQL: pgsql/doc/src/sgml/ref/grant.sgml,v 1.46 2005/04/28 21:47:09 tgl Exp $
PostgreSQL documentation
-->
@ -131,9 +131,10 @@ GRANT { CREATE | ALL [ PRIVILEGES ] }
<term>UPDATE</term>
<listitem>
<para>
Allows <xref linkend="sql-update" endterm="sql-update-title"> of any column of the
specified table. <literal>SELECT ... FOR UPDATE</literal>
also requires this privilege (besides the
Allows <xref linkend="sql-update" endterm="sql-update-title"> of any
column of the specified table. <literal>SELECT ... FOR UPDATE</literal>
and <literal>SELECT ... FOR SHARE</literal>
also require this privilege (besides the
<literal>SELECT</literal> privilege). For sequences, this
privilege allows the use of the <function>nextval</function> and
<function>setval</function> functions.

6
doc/src/sgml/ref/lock.sgml
View File

@ -1,5 +1,5 @@
<!--
$PostgreSQL: pgsql/doc/src/sgml/ref/lock.sgml,v 1.46 2005/01/22 23:22:19 momjian Exp $
$PostgreSQL: pgsql/doc/src/sgml/ref/lock.sgml,v 1.47 2005/04/28 21:47:10 tgl Exp $
PostgreSQL documentation
-->
@ -177,8 +177,8 @@ where <replaceable class="PARAMETER">lockmode</replaceable> is one of:
<command>LOCK TABLE</> is concerned, differing only in the rules
about which modes conflict with which. For information on how to
acquire an actual row-level lock, see <xref linkend="locking-rows">
and the <xref linkend="sql-for-update"
endterm="sql-for-update-title"> in the <command>SELECT</command>
and the <xref linkend="sql-for-update-share"
endterm="sql-for-update-share-title"> in the <command>SELECT</command>
reference documentation.
</para>
</refsect1>

86
doc/src/sgml/ref/pg_resetxlog.sgml
View File

@ -1,5 +1,5 @@
<!--
$PostgreSQL: pgsql/doc/src/sgml/ref/pg_resetxlog.sgml,v 1.9 2004/12/20 01:42:09 tgl Exp $
$PostgreSQL: pgsql/doc/src/sgml/ref/pg_resetxlog.sgml,v 1.10 2005/04/28 21:47:10 tgl Exp $
PostgreSQL documentation
-->
@ -22,6 +22,7 @@ PostgreSQL documentation
<arg> -n </arg>
<arg> -o <replaceable class="parameter">oid</replaceable> </arg>
<arg> -x <replaceable class="parameter">xid</replaceable> </arg>
<arg> -m <replaceable class="parameter">mxid</replaceable> </arg>
<arg> -l <replaceable class="parameter">timelineid</replaceable>,<replaceable class="parameter">fileid</replaceable>,<replaceable class="parameter">seg</replaceable> </arg>
<arg choice="plain"><replaceable>datadir</replaceable></arg>
</cmdsynopsis>
@ -73,34 +74,65 @@ PostgreSQL documentation
</para>
<para>
The <literal>-o</>, <literal>-x</>, and <literal>-l</> switches allow
the next OID, next transaction ID, and WAL starting address values to
The <literal>-o</>, <literal>-x</>, <literal>-m</>, and <literal>-l</>
switches allow the next OID, next transaction ID, next multi-transaction
ID, and WAL starting address values to
be set manually. These are only needed when
<command>pg_resetxlog</command> is unable to determine appropriate values
by reading <filename>pg_control</>. A safe value for the
next transaction ID may be determined by looking for the numerically largest
file name in the directory <filename>pg_clog</> under the data directory,
adding one,
and then multiplying by 1048576. Note that the file names are in
hexadecimal. It is usually easiest to specify the switch value in
hexadecimal too. For example, if <filename>0011</> is the largest entry
in <filename>pg_clog</>, <literal>-x 0x1200000</> will work (five trailing
zeroes provide the proper multiplier).
The WAL starting address should be
larger than any file name currently existing in
the directory <filename>pg_xlog</> under the data directory.
These names are also in hexadecimal and have three parts. The first
part is the <quote>timeline ID</> and should usually be kept the same.
Do not choose a value larger than 255 (<literal>0xFF</>) for the third
part; instead increment the second part and reset the third part to 0.
For example, if <filename>00000001000000320000004A</> is the
largest entry in <filename>pg_xlog</>, <literal>-l 0x1,0x32,0x4B</> will
work; but if the largest entry is
<filename>000000010000003A000000FF</>, choose <literal>-l 0x1,0x3B,0x0</>
or more.
There is no comparably easy way to determine a next OID that's beyond
the largest one in the database, but fortunately it is not critical to
get the next-OID setting right.
by reading <filename>pg_control</>. Safe values may be determined as
follows:
<itemizedlist>
<listitem>
<para>
A safe value for the next transaction ID (<literal>-x</>)
may be determined by looking for the numerically largest
file name in the directory <filename>pg_clog</> under the data directory,
adding one,
and then multiplying by 1048576. Note that the file names are in
hexadecimal. It is usually easiest to specify the switch value in
hexadecimal too. For example, if <filename>0011</> is the largest entry
in <filename>pg_clog</>, <literal>-x 0x1200000</> will work (five
trailing zeroes provide the proper multiplier).
</para>
</listitem>
<listitem>
<para>
A safe value for the next multi-transaction ID (<literal>-m</>)
may be determined by looking for the numerically largest
file name in the directory <filename>pg_multixact/offsets</> under the
data directory, adding one, and then multiplying by 65536. As above,
the file names are in hexadecimal, so the easiest way to do this is to
specify the switch value in hexadecimal and add four zeroes.
</para>
</listitem>
<listitem>
<para>
The WAL starting address (<literal>-l</>) should be
larger than any file name currently existing in
the directory <filename>pg_xlog</> under the data directory.
These names are also in hexadecimal and have three parts. The first
part is the <quote>timeline ID</> and should usually be kept the same.
Do not choose a value larger than 255 (<literal>0xFF</>) for the third
part; instead increment the second part and reset the third part to 0.
For example, if <filename>00000001000000320000004A</> is the
largest entry in <filename>pg_xlog</>, <literal>-l 0x1,0x32,0x4B</> will
work; but if the largest entry is
<filename>000000010000003A000000FF</>, choose <literal>-l 0x1,0x3B,0x0</>
or more.
</para>
</listitem>
<listitem>
<para>
There is no comparably easy way to determine a next OID that's beyond
the largest one in the database, but fortunately it is not critical to
get the next-OID setting right.
</para>
</listitem>
</itemizedlist>
</para>
<para>

87
doc/src/sgml/ref/select.sgml
View File

@ -1,5 +1,5 @@
<!--
$PostgreSQL: pgsql/doc/src/sgml/ref/select.sgml,v 1.85 2005/04/22 15:32:58 momjian Exp $
$PostgreSQL: pgsql/doc/src/sgml/ref/select.sgml,v 1.86 2005/04/28 21:47:10 tgl Exp $
PostgreSQL documentation
-->
@ -30,7 +30,7 @@ SELECT [ ALL | DISTINCT [ ON ( <replaceable class="parameter">expression</replac
[ ORDER BY <replaceable class="parameter">expression</replaceable> [ ASC | DESC | USING <replaceable class="parameter">operator</replaceable> ] [, ...] ]
[ LIMIT { <replaceable class="parameter">count</replaceable> | ALL } ]
[ OFFSET <replaceable class="parameter">start</replaceable> ]
[ FOR UPDATE [ OF <replaceable class="parameter">table_name</replaceable> [, ...] ] ]
[ FOR { UPDATE | SHARE } [ OF <replaceable class="parameter">table_name</replaceable> [, ...] ] ]
where <replaceable class="parameter">from_item</replaceable> can be one of:
@ -142,10 +142,11 @@ where <replaceable class="parameter">from_item</replaceable> can be one of:
<listitem>
<para>
The <literal>FOR UPDATE</literal> clause causes the
<command>SELECT</command> statement to lock the selected rows
against concurrent updates. (See <xref linkend="sql-for-update"
endterm="sql-for-update-title"> below.)
If the <literal>FOR UPDATE</literal> or <literal>FOR SHARE</literal>
clause is specified, the
<command>SELECT</command> statement locks the selected rows
against concurrent updates. (See <xref linkend="sql-for-update-share"
endterm="sql-for-update-share-title"> below.)
</para>
</listitem>
</orderedlist>
@ -153,7 +154,8 @@ where <replaceable class="parameter">from_item</replaceable> can be one of:
<para>
You must have <literal>SELECT</literal> privilege on a table to
read its values. The use of <literal>FOR UPDATE</literal> requires
read its values. The use of <literal>FOR UPDATE</literal> or
<literal>FOR SHARE</literal> requires
<literal>UPDATE</literal> privilege as well.
</para>
</refsect1>
@ -503,7 +505,8 @@ HAVING <replaceable class="parameter">condition</replaceable>
</synopsis>
<replaceable class="parameter">select_statement</replaceable> is
any <command>SELECT</command> statement without an <literal>ORDER
BY</>, <literal>LIMIT</>, or <literal>FOR UPDATE</literal> clause.
BY</>, <literal>LIMIT</>, <literal>FOR UPDATE</literal>, or
<literal>FOR SHARE</literal> clause.
(<literal>ORDER BY</> and <literal>LIMIT</> can be attached to a
subexpression if it is enclosed in parentheses. Without
parentheses, these clauses will be taken to apply to the result of
@ -537,8 +540,9 @@ HAVING <replaceable class="parameter">condition</replaceable>
</para>
<para>
Currently, <literal>FOR UPDATE</> may not be specified either for
a <literal>UNION</> result or for any input of a <literal>UNION</>.
Currently, <literal>FOR UPDATE</> and <literal>FOR SHARE</> may not be
specified either for a <literal>UNION</> result or for any input of a
<literal>UNION</>.
</para>
</refsect2>
@ -552,7 +556,8 @@ HAVING <replaceable class="parameter">condition</replaceable>
</synopsis>
<replaceable class="parameter">select_statement</replaceable> is
any <command>SELECT</command> statement without an <literal>ORDER
BY</>, <literal>LIMIT</>, or <literal>FOR UPDATE</literal> clause.
BY</>, <literal>LIMIT</>, <literal>FOR UPDATE</literal>, or
<literal>FOR SHARE</literal> clause.
</para>
<para>
@ -581,8 +586,9 @@ HAVING <replaceable class="parameter">condition</replaceable>
</para>
<para>
Currently, <literal>FOR UPDATE</> may not be specified either for
an <literal>INTERSECT</> result or for any input of an <literal>INTERSECT</>.
Currently, <literal>FOR UPDATE</> and <literal>FOR SHARE</> may not be
specified either for an <literal>INTERSECT</> result or for any input of
an <literal>INTERSECT</>.
</para>
</refsect2>
@ -596,7 +602,8 @@ HAVING <replaceable class="parameter">condition</replaceable>
</synopsis>
<replaceable class="parameter">select_statement</replaceable> is
any <command>SELECT</command> statement without an <literal>ORDER
BY</>, <literal>LIMIT</>, or <literal>FOR UPDATE</literal> clause.
BY</>, <literal>LIMIT</>, <literal>FOR UPDATE</literal>, or
<literal>FOR SHARE</literal> clause.
</para>
<para>
@ -621,8 +628,9 @@ HAVING <replaceable class="parameter">condition</replaceable>
</para>
<para>
Currently, <literal>FOR UPDATE</> may not be specified either for
an <literal>EXCEPT</> result or for any input of an <literal>EXCEPT</>.
Currently, <literal>FOR UPDATE</> and <literal>FOR SHARE</> may not be
specified either for an <literal>EXCEPT</> result or for any input of
an <literal>EXCEPT</>.
</para>
</refsect2>
@ -789,8 +797,8 @@ OFFSET <replaceable class="parameter">start</replaceable>
</para>
</refsect2>
<refsect2 id="SQL-FOR-UPDATE">
<title id="sql-for-update-title"><literal>FOR UPDATE</literal> Clause</title>
<refsect2 id="SQL-FOR-UPDATE-SHARE">
<title id="sql-for-update-share-title"><literal>FOR UPDATE</literal>/<literal>FOR SHARE</literal> Clause</title>
<para>
The <literal>FOR UPDATE</literal> clause has this form:
@ -799,6 +807,13 @@ FOR UPDATE [ OF <replaceable class="parameter">table_name</replaceable> [, ...]
</synopsis>
</para>
<para>
The closely related <literal>FOR SHARE</literal> clause has this form:
<synopsis>
FOR SHARE [ OF <replaceable class="parameter">table_name</replaceable> [, ...] ]
</synopsis>
</para>
<para>
<literal>FOR UPDATE</literal> causes the rows retrieved by the
<command>SELECT</command> statement to be locked as though for
@ -817,26 +832,44 @@ FOR UPDATE [ OF <replaceable class="parameter">table_name</replaceable> [, ...]
</para>
<para>
If specific tables are named in <literal>FOR UPDATE</literal>,
<literal>FOR SHARE</literal> behaves similarly, except that it
acquires a shared rather than exclusive lock on each retrieved
row. A shared lock blocks other transactions from performing
<command>UPDATE</command>, <command>DELETE</command>, or <command>SELECT
FOR UPDATE</command> on these rows, but it does not prevent them
from performing <command>SELECT FOR SHARE</command>.
</para>
<para>
It is currently not allowed for a single <command>SELECT</command>
statement to include both <literal>FOR UPDATE</literal> and
<literal>FOR SHARE</literal>.
</para>
<para>
If specific tables are named in <literal>FOR UPDATE</literal>
or <literal>FOR SHARE</literal>,
then only rows coming from those tables are locked; any other
tables used in the <command>SELECT</command> are simply read as
usual.
</para>
<para>
<literal>FOR UPDATE</literal> cannot be used in contexts where
returned rows can't be clearly identified with individual table
rows; for example it can't be used with aggregation.
<literal>FOR UPDATE</literal> and <literal>FOR SHARE</literal> cannot be
used in contexts where returned rows can't be clearly identified with
individual table rows; for example they can't be used with aggregation.
</para>
<para>
It is possible for a <command>SELECT</> command using both
<literal>LIMIT</literal> and <literal>FOR UPDATE</literal>
<literal>LIMIT</literal> and <literal>FOR UPDATE/SHARE</literal>
clauses to return fewer rows than specified by <literal>LIMIT</literal>.
This is because <literal>LIMIT</> selects a number of rows,
but might then block requesting a <literal>FOR UPDATE</literal> lock.
Once the <literal>SELECT</> unblocks, the query qualification might not
be met and the row not be returned by <literal>SELECT</>.
This is because <literal>LIMIT</> is applied first. The command
selects the specified number of rows,
but might then block trying to obtain lock on one or more of them.
Once the <literal>SELECT</> unblocks, the row might have been deleted
or updated so that it does not meet the query <literal>WHERE</> condition
anymore, in which case it will not be returned.
</para>
</refsect2>
</refsect1>

4
doc/src/sgml/ref/select_into.sgml
View File

@ -1,5 +1,5 @@
<!--
$PostgreSQL: pgsql/doc/src/sgml/ref/select_into.sgml,v 1.34 2005/03/13 09:36:31 neilc Exp $
$PostgreSQL: pgsql/doc/src/sgml/ref/select_into.sgml,v 1.35 2005/04/28 21:47:10 tgl Exp $
PostgreSQL documentation
-->
@ -31,7 +31,7 @@ SELECT [ ALL | DISTINCT [ ON ( <replaceable class="PARAMETER">expression</replac
[ ORDER BY <replaceable class="PARAMETER">expression</replaceable> [ ASC | DESC | USING <replaceable class="PARAMETER">operator</replaceable> ] [, ...] ]
[ LIMIT { <replaceable class="PARAMETER">count</replaceable> | ALL } ]
[ OFFSET <replaceable class="PARAMETER">start</replaceable> ]
[ FOR UPDATE [ OF <replaceable class="PARAMETER">tablename</replaceable> [, ...] ] ]
[ FOR { UPDATE | SHARE } [ OF <replaceable class="PARAMETER">tablename</replaceable> [, ...] ] ]
</synopsis>
</refsynopsisdiv>

4
doc/src/sgml/sql.sgml
View File

@ -1,5 +1,5 @@
<!--
$PostgreSQL: pgsql/doc/src/sgml/sql.sgml,v 1.35 2005/02/21 02:21:03 neilc Exp $
$PostgreSQL: pgsql/doc/src/sgml/sql.sgml,v 1.36 2005/04/28 21:47:09 tgl Exp $
-->
<chapter id="sql-intro">
@ -866,7 +866,7 @@ SELECT [ ALL | DISTINCT [ ON ( <replaceable class="PARAMETER">expression</replac
[ ORDER BY <replaceable class="PARAMETER">expression</replaceable> [ ASC | DESC | USING <replaceable class="PARAMETER">operator</replaceable> ] [, ...] ]
[ LIMIT { <replaceable class="PARAMETER">count</replaceable> | ALL } ]
[ OFFSET <replaceable class="PARAMETER">start</replaceable> ]
[ FOR UPDATE [ OF <replaceable class="PARAMETER">class_name</replaceable> [, ...] ] ]
[ FOR { UPDATE | SHARE } [ OF <replaceable class="PARAMETER">class_name</replaceable> [, ...] ] ]
</synopsis>
</para>

8
doc/src/sgml/storage.sgml
View File

@ -1,5 +1,5 @@
<!--
$PostgreSQL: pgsql/doc/src/sgml/storage.sgml,v 1.5 2005/04/07 03:31:42 neilc Exp $
$PostgreSQL: pgsql/doc/src/sgml/storage.sgml,v 1.6 2005/04/28 21:47:09 tgl Exp $
-->
<chapter id="storage">
@ -74,6 +74,12 @@ Item
<entry>Subdirectory containing transaction commit status data</entry>
</row>
<row>
<entry><filename>pg_multixact</></entry>
<entry>Subdirectory containing multi-transaction status data
(used for shared row locks)</entry>
</row>
<row>
<entry><filename>pg_subtrans</></entry>
<entry>Subdirectory containing subtransaction status data</entry>

598
src/backend/access/heap/heapam.c
View File

@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/access/heap/heapam.c,v 1.187 2005/04/14 20:03:22 tgl Exp $
* $PostgreSQL: pgsql/src/backend/access/heap/heapam.c,v 1.188 2005/04/28 21:47:10 tgl Exp $
*
*
* INTERFACE ROUTINES
@ -40,12 +40,14 @@
#include "access/heapam.h"
#include "access/hio.h"
#include "access/multixact.h"
#include "access/tuptoaster.h"
#include "access/valid.h"
#include "access/xlogutils.h"
#include "catalog/catalog.h"
#include "catalog/namespace.h"
#include "miscadmin.h"
#include "storage/sinval.h"
#include "utils/inval.h"
#include "utils/relcache.h"
#include "pgstat.h"
@ -1238,30 +1240,81 @@ l1:
}
else if (result == HeapTupleBeingUpdated && wait)
{
TransactionId xwait = HeapTupleHeaderGetXmax(tp.t_data);
/* sleep until concurrent transaction ends */
LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
XactLockTableWait(xwait);
LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
if (!TransactionIdDidCommit(xwait))
goto l1;
TransactionId xwait;
uint16 infomask;
/*
* xwait is committed but if xwait had just marked the tuple for
* update then some other xaction could update this tuple before
* we got to this point.
* Sleep until concurrent transaction ends. Note that we don't care
* if the locker has an exclusive or shared lock, because we need
* exclusive.
*/
if (!TransactionIdEquals(HeapTupleHeaderGetXmax(tp.t_data), xwait))
goto l1;
if (!(tp.t_data->t_infomask & HEAP_XMAX_COMMITTED))
/* must copy state data before unlocking buffer */
xwait = HeapTupleHeaderGetXmax(tp.t_data);
infomask = tp.t_data->t_infomask;
if (infomask & HEAP_XMAX_IS_MULTI)
{
tp.t_data->t_infomask |= HEAP_XMAX_COMMITTED;
SetBufferCommitInfoNeedsSave(buffer);
/* wait for multixact */
LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
MultiXactIdWait((MultiXactId) xwait);
LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
/*
* If xwait had just locked the tuple then some other xact could
* update this tuple before we get to this point. Check for xmax
* change, and start over if so.
*/
if (!(tp.t_data->t_infomask & HEAP_XMAX_IS_MULTI) ||
!TransactionIdEquals(HeapTupleHeaderGetXmax(tp.t_data),
xwait))
goto l1;
/*
* You might think the multixact is necessarily done here, but
* not so: it could have surviving members, namely our own xact
* or other subxacts of this backend. It is legal for us to
* delete the tuple in either case, however (the latter case is
* essentially a situation of upgrading our former shared lock
* to exclusive). We don't bother changing the on-disk hint bits
* since we are about to overwrite the xmax altogether.
*/
}
/* if tuple was marked for update but not updated... */
if (tp.t_data->t_infomask & HEAP_MARKED_FOR_UPDATE)
else
{
/* wait for regular transaction to end */
LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
XactLockTableWait(xwait);
LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
/*
* xwait is done, but if xwait had just locked the tuple then some
* other xact could update this tuple before we get to this point.
* Check for xmax change, and start over if so.
*/
if ((tp.t_data->t_infomask & HEAP_XMAX_IS_MULTI) ||
!TransactionIdEquals(HeapTupleHeaderGetXmax(tp.t_data),
xwait))
goto l1;
/* Otherwise we can mark it committed or aborted */
if (!(tp.t_data->t_infomask & (HEAP_XMAX_COMMITTED |
HEAP_XMAX_INVALID)))
{
if (TransactionIdDidCommit(xwait))
tp.t_data->t_infomask |= HEAP_XMAX_COMMITTED;
else
tp.t_data->t_infomask |= HEAP_XMAX_INVALID;
SetBufferCommitInfoNeedsSave(buffer);
}
}
/*
* We may overwrite if previous xmax aborted, or if it committed
* but only locked the tuple without updating it.
*/
if (tp.t_data->t_infomask & (HEAP_XMAX_INVALID |
HEAP_IS_LOCKED))
result = HeapTupleMayBeUpdated;
else
result = HeapTupleUpdated;
@ -1290,7 +1343,8 @@ l1:
/* store transaction information of xact deleting the tuple */
tp.t_data->t_infomask &= ~(HEAP_XMAX_COMMITTED |
HEAP_XMAX_INVALID |
HEAP_MARKED_FOR_UPDATE |
HEAP_XMAX_IS_MULTI |
HEAP_IS_LOCKED |
HEAP_MOVED);
HeapTupleHeaderSetXmax(tp.t_data, xid);
HeapTupleHeaderSetCmax(tp.t_data, cid);
@ -1465,30 +1519,81 @@ l2:
}
else if (result == HeapTupleBeingUpdated && wait)
{
TransactionId xwait = HeapTupleHeaderGetXmax(oldtup.t_data);
/* sleep until concurrent transaction ends */
LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
XactLockTableWait(xwait);
LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
if (!TransactionIdDidCommit(xwait))
goto l2;
TransactionId xwait;
uint16 infomask;
/*
* xwait is committed but if xwait had just marked the tuple for
* update then some other xaction could update this tuple before
* we got to this point.
* Sleep until concurrent transaction ends. Note that we don't care
* if the locker has an exclusive or shared lock, because we need
* exclusive.
*/
if (!TransactionIdEquals(HeapTupleHeaderGetXmax(oldtup.t_data), xwait))
goto l2;
if (!(oldtup.t_data->t_infomask & HEAP_XMAX_COMMITTED))
/* must copy state data before unlocking buffer */
xwait = HeapTupleHeaderGetXmax(oldtup.t_data);
infomask = oldtup.t_data->t_infomask;
if (infomask & HEAP_XMAX_IS_MULTI)
{
oldtup.t_data->t_infomask |= HEAP_XMAX_COMMITTED;
SetBufferCommitInfoNeedsSave(buffer);
/* wait for multixact */
LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
MultiXactIdWait((MultiXactId) xwait);
LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
/*
* If xwait had just locked the tuple then some other xact could
* update this tuple before we get to this point. Check for xmax
* change, and start over if so.
*/
if (!(oldtup.t_data->t_infomask & HEAP_XMAX_IS_MULTI) ||
!TransactionIdEquals(HeapTupleHeaderGetXmax(oldtup.t_data),
xwait))
goto l2;
/*
* You might think the multixact is necessarily done here, but
* not so: it could have surviving members, namely our own xact
* or other subxacts of this backend. It is legal for us to
* update the tuple in either case, however (the latter case is
* essentially a situation of upgrading our former shared lock
* to exclusive). We don't bother changing the on-disk hint bits
* since we are about to overwrite the xmax altogether.
*/
}
/* if tuple was marked for update but not updated... */
if (oldtup.t_data->t_infomask & HEAP_MARKED_FOR_UPDATE)
else
{
/* wait for regular transaction to end */
LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
XactLockTableWait(xwait);
LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
/*
* xwait is done, but if xwait had just locked the tuple then some
* other xact could update this tuple before we get to this point.
* Check for xmax change, and start over if so.
*/
if ((oldtup.t_data->t_infomask & HEAP_XMAX_IS_MULTI) ||
!TransactionIdEquals(HeapTupleHeaderGetXmax(oldtup.t_data),
xwait))
goto l2;
/* Otherwise we can mark it committed or aborted */
if (!(oldtup.t_data->t_infomask & (HEAP_XMAX_COMMITTED |
HEAP_XMAX_INVALID)))
{
if (TransactionIdDidCommit(xwait))
oldtup.t_data->t_infomask |= HEAP_XMAX_COMMITTED;
else
oldtup.t_data->t_infomask |= HEAP_XMAX_INVALID;
SetBufferCommitInfoNeedsSave(buffer);
}
}
/*
* We may overwrite if previous xmax aborted, or if it committed
* but only locked the tuple without updating it.
*/
if (oldtup.t_data->t_infomask & (HEAP_XMAX_INVALID |
HEAP_IS_LOCKED))
result = HeapTupleMayBeUpdated;
else
result = HeapTupleUpdated;
@ -1556,7 +1661,8 @@ l2:
{
oldtup.t_data->t_infomask &= ~(HEAP_XMAX_COMMITTED |
HEAP_XMAX_INVALID |
HEAP_MARKED_FOR_UPDATE |
HEAP_XMAX_IS_MULTI |
HEAP_IS_LOCKED |
HEAP_MOVED);
HeapTupleHeaderSetXmax(oldtup.t_data, xid);
HeapTupleHeaderSetCmax(oldtup.t_data, cid);
@ -1642,7 +1748,8 @@ l2:
{
oldtup.t_data->t_infomask &= ~(HEAP_XMAX_COMMITTED |
HEAP_XMAX_INVALID |
HEAP_MARKED_FOR_UPDATE |
HEAP_XMAX_IS_MULTI |
HEAP_IS_LOCKED |
HEAP_MOVED);
HeapTupleHeaderSetXmax(oldtup.t_data, xid);
HeapTupleHeaderSetCmax(oldtup.t_data, cid);
@ -1739,17 +1846,18 @@ simple_heap_update(Relation relation, ItemPointer otid, HeapTuple tup)
}
/*
* heap_mark4update - mark a tuple for update
* heap_lock_tuple - lock a tuple in shared or exclusive mode
*/
HTSU_Result
heap_mark4update(Relation relation, HeapTuple tuple, Buffer *buffer,
CommandId cid)
heap_lock_tuple(Relation relation, HeapTuple tuple, Buffer *buffer,
CommandId cid, LockTupleMode mode)
{
TransactionId xid = GetCurrentTransactionId();
TransactionId xid;
ItemPointer tid = &(tuple->t_self);
ItemId lp;
PageHeader dp;
HTSU_Result result;
uint16 new_infomask;
*buffer = ReadBuffer(relation, ItemPointerGetBlockNumber(tid));
LockBuffer(*buffer, BUFFER_LOCK_EXCLUSIVE);
@ -1767,38 +1875,93 @@ l3:
{
LockBuffer(*buffer, BUFFER_LOCK_UNLOCK);
ReleaseBuffer(*buffer);
elog(ERROR, "attempted to mark4update invisible tuple");
elog(ERROR, "attempted to lock invisible tuple");
}
else if (result == HeapTupleBeingUpdated)
{
TransactionId xwait = HeapTupleHeaderGetXmax(tuple->t_data);
/* sleep until concurrent transaction ends */
LockBuffer(*buffer, BUFFER_LOCK_UNLOCK);
XactLockTableWait(xwait);
LockBuffer(*buffer, BUFFER_LOCK_EXCLUSIVE);
if (!TransactionIdDidCommit(xwait))
goto l3;
/*
* xwait is committed but if xwait had just marked the tuple for
* update then some other xaction could update this tuple before
* we got to this point.
*/
if (!TransactionIdEquals(HeapTupleHeaderGetXmax(tuple->t_data), xwait))
goto l3;
if (!(tuple->t_data->t_infomask & HEAP_XMAX_COMMITTED))
{
tuple->t_data->t_infomask |= HEAP_XMAX_COMMITTED;
SetBufferCommitInfoNeedsSave(*buffer);
}
/* if tuple was marked for update but not updated... */
if (tuple->t_data->t_infomask & HEAP_MARKED_FOR_UPDATE)
if (mode == LockTupleShared &&
(tuple->t_data->t_infomask & HEAP_XMAX_SHARED_LOCK))
result = HeapTupleMayBeUpdated;
else
result = HeapTupleUpdated;
{
TransactionId xwait;
uint16 infomask;
/*
* Sleep until concurrent transaction ends.
*/
/* must copy state data before unlocking buffer */
xwait = HeapTupleHeaderGetXmax(tuple->t_data);
infomask = tuple->t_data->t_infomask;
if (infomask & HEAP_XMAX_IS_MULTI)
{
/* wait for multixact */
LockBuffer(*buffer, BUFFER_LOCK_UNLOCK);
MultiXactIdWait((MultiXactId) xwait);
LockBuffer(*buffer, BUFFER_LOCK_EXCLUSIVE);
/*
* If xwait had just locked the tuple then some other xact
* could update this tuple before we get to this point.
* Check for xmax change, and start over if so.
*/
if (!(tuple->t_data->t_infomask & HEAP_XMAX_IS_MULTI) ||
!TransactionIdEquals(HeapTupleHeaderGetXmax(tuple->t_data),
xwait))
goto l3;
/*
* You might think the multixact is necessarily done here, but
* not so: it could have surviving members, namely our own xact
* or other subxacts of this backend. It is legal for us to
* lock the tuple in either case, however. We don't bother
* changing the on-disk hint bits since we are about to
* overwrite the xmax altogether.
*/
}
else
{
/* wait for regular transaction to end */
LockBuffer(*buffer, BUFFER_LOCK_UNLOCK);
XactLockTableWait(xwait);
LockBuffer(*buffer, BUFFER_LOCK_EXCLUSIVE);
/*
* xwait is done, but if xwait had just locked the tuple then
* some other xact could update this tuple before we get to
* this point. Check for xmax change, and start over if so.
*/
if ((tuple->t_data->t_infomask & HEAP_XMAX_IS_MULTI) ||
!TransactionIdEquals(HeapTupleHeaderGetXmax(tuple->t_data),
xwait))
goto l3;
/* Otherwise we can mark it committed or aborted */
if (!(tuple->t_data->t_infomask & (HEAP_XMAX_COMMITTED |
HEAP_XMAX_INVALID)))
{
if (TransactionIdDidCommit(xwait))
tuple->t_data->t_infomask |= HEAP_XMAX_COMMITTED;
else
tuple->t_data->t_infomask |= HEAP_XMAX_INVALID;
SetBufferCommitInfoNeedsSave(*buffer);
}
}
/*
* We may lock if previous xmax aborted, or if it committed
* but only locked the tuple without updating it.
*/
if (tuple->t_data->t_infomask & (HEAP_XMAX_INVALID |
HEAP_IS_LOCKED))
result = HeapTupleMayBeUpdated;
else
result = HeapTupleUpdated;
}
}
if (result != HeapTupleMayBeUpdated)
{
Assert(result == HeapTupleSelfUpdated || result == HeapTupleUpdated);
@ -1808,21 +1971,173 @@ l3:
}
/*
* XLOG stuff: no logging is required as long as we have no
* savepoints. For savepoints private log could be used...
* Compute the new xmax and infomask to store into the tuple. Note we
* do not modify the tuple just yet, because that would leave it in the
* wrong state if multixact.c elogs.
*/
PageSetTLI(BufferGetPage(*buffer), ThisTimeLineID);
xid = GetCurrentTransactionId();
/* store transaction information of xact marking the tuple */
tuple->t_data->t_infomask &= ~(HEAP_XMAX_COMMITTED |
HEAP_XMAX_INVALID |
HEAP_MOVED);
tuple->t_data->t_infomask |= HEAP_MARKED_FOR_UPDATE;
new_infomask = tuple->t_data->t_infomask;
new_infomask &= ~(HEAP_XMAX_COMMITTED |
HEAP_XMAX_INVALID |
HEAP_XMAX_IS_MULTI |
HEAP_IS_LOCKED |
HEAP_MOVED);
if (mode == LockTupleShared)
{
TransactionId xmax = HeapTupleHeaderGetXmax(tuple->t_data);
uint16 old_infomask = tuple->t_data->t_infomask;
/*
* If this is the first acquisition of a shared lock in the current
* transaction, set my per-backend OldestMemberMXactId setting.
* We can be certain that the transaction will never become a
* member of any older MultiXactIds than that. (We have to do this
* even if we end up just using our own TransactionId below, since
* some other backend could incorporate our XID into a MultiXact
* immediately afterwards.)
*/
MultiXactIdSetOldestMember();
new_infomask |= HEAP_XMAX_SHARED_LOCK;
/*
* Check to see if we need a MultiXactId because there are multiple
* lockers.
*
* HeapTupleSatisfiesUpdate will have set the HEAP_XMAX_INVALID
* bit if the xmax was a MultiXactId but it was not running anymore.
* There is a race condition, which is that the MultiXactId may have
* finished since then, but that uncommon case is handled within
* MultiXactIdExpand.
*
* There is a similar race condition possible when the old xmax was
* a regular TransactionId. We test TransactionIdIsInProgress again
* just to narrow the window, but it's still possible to end up
* creating an unnecessary MultiXactId. Fortunately this is harmless.
*/
if (!(old_infomask & (HEAP_XMAX_INVALID | HEAP_XMAX_COMMITTED)))
{
if (old_infomask & HEAP_XMAX_IS_MULTI)
{
/*
* If the XMAX is already a MultiXactId, then we need to
* expand it to include our own TransactionId.
*/
xid = MultiXactIdExpand(xmax, true, xid);
new_infomask |= HEAP_XMAX_IS_MULTI;
}
else if (TransactionIdIsInProgress(xmax))
{
if (TransactionIdEquals(xmax, xid))
{
/*
* If the old locker is ourselves, we'll just mark the
* tuple again with our own TransactionId. However we
* have to consider the possibility that we had
* exclusive rather than shared lock before --- if so,
* be careful to preserve the exclusivity of the lock.
*/
if (!(old_infomask & HEAP_XMAX_SHARED_LOCK))
{
new_infomask &= ~HEAP_XMAX_SHARED_LOCK;
new_infomask |= HEAP_XMAX_EXCL_LOCK;
mode = LockTupleExclusive;
}
}
else
{
/*
* If the Xmax is a valid TransactionId, then we need to
* create a new MultiXactId that includes both the old
* locker and our own TransactionId.
*/
xid = MultiXactIdExpand(xmax, false, xid);
new_infomask |= HEAP_XMAX_IS_MULTI;
}
}
else
{
/*
* Can get here iff HeapTupleSatisfiesUpdate saw the old
* xmax as running, but it finished before
* TransactionIdIsInProgress() got to run. Treat it like
* there's no locker in the tuple.
*/
}
}
else
{
/*
* There was no previous locker, so just insert our own
* TransactionId.
*/
}
}
else
{
/* We want an exclusive lock on the tuple */
new_infomask |= HEAP_XMAX_EXCL_LOCK;
}
START_CRIT_SECTION();
/*
* Store transaction information of xact locking the tuple.
*
* Note: our CID is meaningless if storing a MultiXactId, but no harm
* in storing it anyway.
*/
tuple->t_data->t_infomask = new_infomask;
HeapTupleHeaderSetXmax(tuple->t_data, xid);
HeapTupleHeaderSetCmax(tuple->t_data, cid);
/* Make sure there is no forward chain link in t_ctid */
tuple->t_data->t_ctid = *tid;
/*
* XLOG stuff. You might think that we don't need an XLOG record because
* there is no state change worth restoring after a crash. You would be
* wrong however: we have just written either a TransactionId or a
* MultiXactId that may never have been seen on disk before, and we need
* to make sure that there are XLOG entries covering those ID numbers.
* Else the same IDs might be re-used after a crash, which would be
* disastrous if this page made it to disk before the crash. Essentially
* we have to enforce the WAL log-before-data rule even in this case.
*/
if (!relation->rd_istemp)
{
xl_heap_lock xlrec;
XLogRecPtr recptr;
XLogRecData rdata[2];
xlrec.target.node = relation->rd_node;
xlrec.target.tid = tuple->t_self;
xlrec.shared_lock = (mode == LockTupleShared);
rdata[0].buffer = InvalidBuffer;
rdata[0].data = (char *) &xlrec;
rdata[0].len = SizeOfHeapLock;
rdata[0].next = &(rdata[1]);
rdata[1].buffer = *buffer;
rdata[1].data = NULL;
rdata[1].len = 0;
rdata[1].next = NULL;
recptr = XLogInsert(RM_HEAP_ID, XLOG_HEAP_LOCK, rdata);
PageSetLSN(dp, recptr);
PageSetTLI(dp, ThisTimeLineID);
}
else
{
/* No XLOG record, but still need to flag that XID exists on disk */
MyXactMadeTempRelUpdate = true;
}
END_CRIT_SECTION();
LockBuffer(*buffer, BUFFER_LOCK_UNLOCK);
WriteNoReleaseBuffer(*buffer);
@ -1832,17 +2147,6 @@ l3:
/* ----------------
* heap_markpos - mark scan position
*
* Note:
* Should only one mark be maintained per scan at one time.
* Check if this can be done generally--say calls to get the
* next/previous tuple and NEVER pass struct scandesc to the
* user AM's. Now, the mark is sent to the executor for safekeeping.
* Probably can store this info into a GENERAL scan structure.
*
* May be best to change this call to store the marked position
* (up to 2?) in the scan structure itself.
* Fix to use the proper caching structure.
* ----------------
*/
void
@ -1858,19 +2162,6 @@ heap_markpos(HeapScanDesc scan)
/* ----------------
* heap_restrpos - restore position to marked location
*
* Note: there are bad side effects here. If we were past the end
* of a relation when heapmarkpos is called, then if the relation is
* extended via insert, then the next call to heaprestrpos will set
* cause the added tuples to be visible when the scan continues.
* Problems also arise if the TID's are rearranged!!!
*
* XXX might be better to do direct access instead of
* using the generality of heapgettup().
*
* XXX It is very possible that when a scan is restored, that a tuple
* XXX which previously qualified may fail for time range purposes, unless
* XXX some form of locking exists (ie., portals currently can act funny.
* ----------------
*/
void
@ -1996,8 +2287,7 @@ log_heap_update(Relation reln, Buffer oldbuf, ItemPointerData from,
{
TransactionId xid[2]; /* xmax, xmin */
if (newtup->t_data->t_infomask & (HEAP_XMAX_INVALID |
HEAP_MARKED_FOR_UPDATE))
if (newtup->t_data->t_infomask & (HEAP_XMAX_INVALID | HEAP_IS_LOCKED))
xid[0] = InvalidTransactionId;
else
xid[0] = HeapTupleHeaderGetXmax(newtup->t_data);
@ -2185,7 +2475,8 @@ heap_xlog_delete(bool redo, XLogRecPtr lsn, XLogRecord *record)
{
htup->t_infomask &= ~(HEAP_XMAX_COMMITTED |
HEAP_XMAX_INVALID |
HEAP_MARKED_FOR_UPDATE |
HEAP_XMAX_IS_MULTI |
HEAP_IS_LOCKED |
HEAP_MOVED);
HeapTupleHeaderSetXmax(htup, record->xl_xid);
HeapTupleHeaderSetCmax(htup, FirstCommandId);
@ -2365,7 +2656,8 @@ heap_xlog_update(bool redo, XLogRecPtr lsn, XLogRecord *record, bool move)
{
htup->t_infomask &= ~(HEAP_XMAX_COMMITTED |
HEAP_XMAX_INVALID |
HEAP_MARKED_FOR_UPDATE |
HEAP_XMAX_IS_MULTI |
HEAP_IS_LOCKED |
HEAP_MOVED);
HeapTupleHeaderSetXmax(htup, record->xl_xid);
HeapTupleHeaderSetCmax(htup, FirstCommandId);
@ -2487,6 +2779,82 @@ newsame:;
}
static void
heap_xlog_lock(bool redo, XLogRecPtr lsn, XLogRecord *record)
{
xl_heap_lock *xlrec = (xl_heap_lock *) XLogRecGetData(record);
Relation reln;
Buffer buffer;
Page page;
OffsetNumber offnum;
ItemId lp = NULL;
HeapTupleHeader htup;
if (redo && (record->xl_info & XLR_BKP_BLOCK_1))
return;
reln = XLogOpenRelation(redo, RM_HEAP_ID, xlrec->target.node);
if (!RelationIsValid(reln))
return;
buffer = XLogReadBuffer(false, reln,
ItemPointerGetBlockNumber(&(xlrec->target.tid)));
if (!BufferIsValid(buffer))
elog(PANIC, "heap_lock_%sdo: no block", (redo) ? "re" : "un");
page = (Page) BufferGetPage(buffer);
if (PageIsNew((PageHeader) page))
elog(PANIC, "heap_lock_%sdo: uninitialized page", (redo) ? "re" : "un");
if (redo)
{
if (XLByteLE(lsn, PageGetLSN(page))) /* changes are applied */
{
LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
ReleaseBuffer(buffer);
return;
}
}
else if (XLByteLT(PageGetLSN(page), lsn)) /* changes are not applied
* ?! */
elog(PANIC, "heap_lock_undo: bad page LSN");
offnum = ItemPointerGetOffsetNumber(&(xlrec->target.tid));
if (PageGetMaxOffsetNumber(page) >= offnum)
lp = PageGetItemId(page, offnum);
if (PageGetMaxOffsetNumber(page) < offnum || !ItemIdIsUsed(lp))
elog(PANIC, "heap_lock_%sdo: invalid lp", (redo) ? "re" : "un");
htup = (HeapTupleHeader) PageGetItem(page, lp);
if (redo)
{
/*
* Presently, we don't bother to restore the locked state, but
* just set the XMAX_INVALID bit.
*/
htup->t_infomask &= ~(HEAP_XMAX_COMMITTED |
HEAP_XMAX_INVALID |
HEAP_XMAX_IS_MULTI |
HEAP_IS_LOCKED |
HEAP_MOVED);
htup->t_infomask |= HEAP_XMAX_INVALID;
HeapTupleHeaderSetXmax(htup, record->xl_xid);
HeapTupleHeaderSetCmax(htup, FirstCommandId);
/* Make sure there is no forward chain link in t_ctid */
htup->t_ctid = xlrec->target.tid;
PageSetLSN(page, lsn);
PageSetTLI(page, ThisTimeLineID);
LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
WriteBuffer(buffer);
return;
}
elog(PANIC, "heap_lock_undo: unimplemented");
}
void
heap_redo(XLogRecPtr lsn, XLogRecord *record)
{
@ -2505,6 +2873,8 @@ heap_redo(XLogRecPtr lsn, XLogRecord *record)
heap_xlog_clean(true, lsn, record);
else if (info == XLOG_HEAP_NEWPAGE)
heap_xlog_newpage(true, lsn, record);
else if (info == XLOG_HEAP_LOCK)
heap_xlog_lock(true, lsn, record);
else
elog(PANIC, "heap_redo: unknown op code %u", info);
}
@ -2527,6 +2897,8 @@ heap_undo(XLogRecPtr lsn, XLogRecord *record)
heap_xlog_clean(false, lsn, record);
else if (info == XLOG_HEAP_NEWPAGE)
heap_xlog_newpage(false, lsn, record);
else if (info == XLOG_HEAP_LOCK)
heap_xlog_lock(false, lsn, record);
else
elog(PANIC, "heap_undo: unknown op code %u", info);
}
@ -2589,6 +2961,16 @@ heap_desc(char *buf, uint8 xl_info, char *rec)
xlrec->node.spcNode, xlrec->node.dbNode,
xlrec->node.relNode, xlrec->blkno);
}
else if (info == XLOG_HEAP_LOCK)
{
xl_heap_lock *xlrec = (xl_heap_lock *) rec;
if (xlrec->shared_lock)
strcat(buf, "shared_lock: ");
else
strcat(buf, "exclusive_lock: ");
out_target(buf, &(xlrec->target));
}
else
strcat(buf, "UNKNOWN");
}

4
src/backend/access/transam/Makefile
View File

@ -4,7 +4,7 @@
# Makefile for access/transam
#
# IDENTIFICATION
# $PostgreSQL: pgsql/src/backend/access/transam/Makefile,v 1.19 2004/07/01 00:49:42 tgl Exp $
# $PostgreSQL: pgsql/src/backend/access/transam/Makefile,v 1.20 2005/04/28 21:47:10 tgl Exp $
#
#-------------------------------------------------------------------------
@ -12,7 +12,7 @@ subdir = src/backend/access/transam
top_builddir = ../../../..
include $(top_builddir)/src/Makefile.global
OBJS = clog.o transam.o varsup.o xact.o xlog.o xlogutils.o rmgr.o slru.o subtrans.o
OBJS = clog.o transam.o varsup.o xact.o xlog.o xlogutils.o rmgr.o slru.o subtrans.o multixact.o
all: SUBSYS.o

1557
src/backend/access/transam/multixact.c Normal file
View File

File diff suppressed because it is too large Load Diff

12
src/backend/access/transam/xact.c
View File

@ -10,7 +10,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/access/transam/xact.c,v 1.199 2005/04/11 19:51:14 tgl Exp $
* $PostgreSQL: pgsql/src/backend/access/transam/xact.c,v 1.200 2005/04/28 21:47:10 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -20,6 +20,7 @@
#include <time.h>
#include <unistd.h>
#include "access/multixact.h"
#include "access/subtrans.h"
#include "access/xact.h"
#include "catalog/heap.h"
@ -1565,6 +1566,8 @@ CommitTransaction(void)
*/
smgrDoPendingDeletes(true);
AtEOXact_MultiXact();
ResourceOwnerRelease(TopTransactionResourceOwner,
RESOURCE_RELEASE_LOCKS,
true, true);
@ -1710,6 +1713,7 @@ AbortTransaction(void)
AtEOXact_Buffers(false);
AtEOXact_Inval(false);
smgrDoPendingDeletes(false);
AtEOXact_MultiXact();
ResourceOwnerRelease(TopTransactionResourceOwner,
RESOURCE_RELEASE_LOCKS,
false, true);
@ -3622,9 +3626,9 @@ static void
ShowTransactionState(const char *str)
{
/* skip work if message will definitely not be printed */
if (log_min_messages <= DEBUG2 || client_min_messages <= DEBUG2)
if (log_min_messages <= DEBUG3 || client_min_messages <= DEBUG3)
{
elog(DEBUG2, "%s", str);
elog(DEBUG3, "%s", str);
ShowTransactionStateRec(CurrentTransactionState);
}
}
@ -3640,7 +3644,7 @@ ShowTransactionStateRec(TransactionState s)
ShowTransactionStateRec(s->parent);
/* use ereport to suppress computation if msg will not be printed */
ereport(DEBUG2,
ereport(DEBUG3,
(errmsg_internal("name: %s; blockState: %13s; state: %7s, xid/subid/cid: %u/%u/%u, nestlvl: %d, children: %s",
PointerIsValid(s->name) ? s->name : "unnamed",
BlockStateAsString(s->blockState),

65
src/backend/access/transam/xlog.c
View File

@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/backend/access/transam/xlog.c,v 1.188 2005/04/23 18:49:54 tgl Exp $
* $PostgreSQL: pgsql/src/backend/access/transam/xlog.c,v 1.189 2005/04/28 21:47:10 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -23,6 +23,7 @@
#include <sys/time.h>
#include "access/clog.h"
#include "access/multixact.h"
#include "access/subtrans.h"
#include "access/xact.h"
#include "access/xlog.h"
@ -3534,11 +3535,13 @@ BootStrapXLOG(void)
checkPoint.ThisTimeLineID = ThisTimeLineID;
checkPoint.nextXid = FirstNormalTransactionId;
checkPoint.nextOid = FirstBootstrapObjectId;
checkPoint.nextMulti = FirstMultiXactId;
checkPoint.time = time(NULL);
ShmemVariableCache->nextXid = checkPoint.nextXid;
ShmemVariableCache->nextOid = checkPoint.nextOid;
ShmemVariableCache->oidCount = 0;
MultiXactSetNextMXact(checkPoint.nextMulti);
/* Set up the XLOG page header */
page->xlp_magic = XLOG_PAGE_MAGIC;
@ -3613,6 +3616,7 @@ BootStrapXLOG(void)
/* Bootstrap the commit log, too */
BootStrapCLOG();
BootStrapSUBTRANS();
BootStrapMultiXact();
}
static char *
@ -4187,8 +4191,8 @@ StartupXLOG(void)
checkPoint.undo.xlogid, checkPoint.undo.xrecoff,
wasShutdown ? "TRUE" : "FALSE")));
ereport(LOG,
(errmsg("next transaction ID: %u; next OID: %u",
checkPoint.nextXid, checkPoint.nextOid)));
(errmsg("next transaction ID: %u; next OID: %u; next MultiXactId: %u",
checkPoint.nextXid, checkPoint.nextOid, checkPoint.nextMulti)));
if (!TransactionIdIsNormal(checkPoint.nextXid))
ereport(PANIC,
(errmsg("invalid next transaction ID")));
@ -4196,6 +4200,7 @@ StartupXLOG(void)
ShmemVariableCache->nextXid = checkPoint.nextXid;
ShmemVariableCache->nextOid = checkPoint.nextOid;
ShmemVariableCache->oidCount = 0;
MultiXactSetNextMXact(checkPoint.nextMulti);
/*
* We must replay WAL entries using the same TimeLineID they were
@ -4546,9 +4551,10 @@ StartupXLOG(void)
ControlFile->time = time(NULL);
UpdateControlFile();
/* Start up the commit log, too */
/* Start up the commit log and related stuff, too */
StartupCLOG();
StartupSUBTRANS();
StartupMultiXact();
ereport(LOG,
(errmsg("database system is ready")));
@ -4737,6 +4743,7 @@ ShutdownXLOG(int code, Datum arg)
CreateCheckPoint(true, true);
ShutdownCLOG();
ShutdownSUBTRANS();
ShutdownMultiXact();
CritSectionCount--;
ereport(LOG,
@ -4919,6 +4926,8 @@ CreateCheckPoint(bool shutdown, bool force)
checkPoint.nextOid += ShmemVariableCache->oidCount;
LWLockRelease(OidGenLock);
checkPoint.nextMulti = MultiXactGetCheckptMulti(shutdown);
/*
* Having constructed the checkpoint record, ensure all shmem disk
* buffers and commit-log buffers are flushed to disk.
@ -4938,6 +4947,7 @@ CreateCheckPoint(bool shutdown, bool force)
CheckPointCLOG();
CheckPointSUBTRANS();
CheckPointMultiXact();
FlushBufferPool();
START_CRIT_SECTION();
@ -5054,6 +5064,33 @@ XLogPutNextOid(Oid nextOid)
rdata.len = sizeof(Oid);
rdata.next = NULL;
(void) XLogInsert(RM_XLOG_ID, XLOG_NEXTOID, &rdata);
/*
* We need not flush the NEXTOID record immediately, because any of the
* just-allocated OIDs could only reach disk as part of a tuple insert
* or update that would have its own XLOG record that must follow the
* NEXTOID record. Therefore, the standard buffer LSN interlock applied
* to those records will ensure no such OID reaches disk before the
* NEXTOID record does.
*/
}
/*
* Write a NEXT_MULTIXACT log record
*/
void
XLogPutNextMultiXactId(MultiXactId nextMulti)
{
XLogRecData rdata;
rdata.buffer = InvalidBuffer;
rdata.data = (char *) (&nextMulti);
rdata.len = sizeof(MultiXactId);
rdata.next = NULL;
(void) XLogInsert(RM_XLOG_ID, XLOG_NEXTMULTI, &rdata);
/*
* We do not flush here either; this assumes that heap_lock_tuple() will
* always generate a WAL record. See notes therein.
*/
}
/*
@ -5075,6 +5112,14 @@ xlog_redo(XLogRecPtr lsn, XLogRecord *record)
ShmemVariableCache->oidCount = 0;
}
}
else if (info == XLOG_NEXTMULTI)
{
MultiXactId nextMulti;
memcpy(&nextMulti, XLogRecGetData(record), sizeof(MultiXactId));
MultiXactAdvanceNextMXact(nextMulti);
}
else if (info == XLOG_CHECKPOINT_SHUTDOWN)
{
CheckPoint checkPoint;
@ -5084,6 +5129,7 @@ xlog_redo(XLogRecPtr lsn, XLogRecord *record)
ShmemVariableCache->nextXid = checkPoint.nextXid;
ShmemVariableCache->nextOid = checkPoint.nextOid;
ShmemVariableCache->oidCount = 0;
MultiXactSetNextMXact(checkPoint.nextMulti);
/*
* TLI may change in a shutdown checkpoint, but it shouldn't
@ -5115,6 +5161,7 @@ xlog_redo(XLogRecPtr lsn, XLogRecord *record)
ShmemVariableCache->nextOid = checkPoint.nextOid;
ShmemVariableCache->oidCount = 0;
}
MultiXactAdvanceNextMXact(checkPoint.nextMulti);
/* TLI should not change in an on-line checkpoint */
if (checkPoint.ThisTimeLineID != ThisTimeLineID)
ereport(PANIC,
@ -5139,11 +5186,12 @@ xlog_desc(char *buf, uint8 xl_info, char *rec)
CheckPoint *checkpoint = (CheckPoint *) rec;
sprintf(buf + strlen(buf), "checkpoint: redo %X/%X; undo %X/%X; "
"tli %u; xid %u; oid %u; %s",
"tli %u; xid %u; oid %u; multi %u; %s",
checkpoint->redo.xlogid, checkpoint->redo.xrecoff,
checkpoint->undo.xlogid, checkpoint->undo.xrecoff,
checkpoint->ThisTimeLineID, checkpoint->nextXid,
checkpoint->nextOid,
checkpoint->nextMulti,
(info == XLOG_CHECKPOINT_SHUTDOWN) ? "shutdown" : "online");
}
else if (info == XLOG_NEXTOID)
@ -5153,6 +5201,13 @@ xlog_desc(char *buf, uint8 xl_info, char *rec)
memcpy(&nextOid, rec, sizeof(Oid));
sprintf(buf + strlen(buf), "nextOid: %u", nextOid);
}
else if (info == XLOG_NEXTMULTI)
{
MultiXactId multi;
memcpy(&multi, rec, sizeof(MultiXactId));
sprintf(buf + strlen(buf), "nextMultiXact: %u", multi);
}
else
strcat(buf, "UNKNOWN");
}

5
src/backend/catalog/index.c
View File

@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/catalog/index.c,v 1.252 2005/04/14 20:03:23 tgl Exp $
* $PostgreSQL: pgsql/src/backend/catalog/index.c,v 1.253 2005/04/28 21:47:11 tgl Exp $
*
*
* INTERFACE ROUTINES
@ -471,7 +471,7 @@ index_create(Oid heapRelationId,
int i;
/*
* Only SELECT ... FOR UPDATE are allowed while doing this
* Only SELECT ... FOR UPDATE/SHARE are allowed while doing this
*/
heapRelation = heap_open(heapRelationId, ShareLock);
@ -1460,6 +1460,7 @@ IndexBuildHeapScan(Relation heapRelation,
* a system catalog, because we often release lock on
* system catalogs before committing.
*/
Assert(!(heapTuple->t_data->t_infomask & HEAP_XMAX_IS_MULTI));
if (!TransactionIdIsCurrentTransactionId(
HeapTupleHeaderGetXmax(heapTuple->t_data))
&& !IsSystemRelation(heapRelation))

4
src/backend/commands/portalcmds.c
View File

@ -14,7 +14,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/commands/portalcmds.c,v 1.40 2005/04/11 15:59:34 tgl Exp $
* $PostgreSQL: pgsql/src/backend/commands/portalcmds.c,v 1.41 2005/04/28 21:47:11 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -90,7 +90,7 @@ PerformCursorOpen(DeclareCursorStmt *stmt, ParamListInfo params)
if (query->rowMarks != NIL)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("DECLARE CURSOR ... FOR UPDATE is not supported"),
errmsg("DECLARE CURSOR ... FOR UPDATE/SHARE is not supported"),
errdetail("Cursors must be READ ONLY.")));
plan = planner(query, true, stmt->options, NULL);

9
src/backend/commands/trigger.c
View File

@ -7,7 +7,7 @@
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/commands/trigger.c,v 1.186 2005/04/14 20:03:24 tgl Exp $
* $PostgreSQL: pgsql/src/backend/commands/trigger.c,v 1.187 2005/04/28 21:47:11 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -1592,12 +1592,12 @@ GetTupleForTrigger(EState *estate, ResultRelInfo *relinfo,
HTSU_Result test;
/*
* mark tuple for update
* lock tuple for update
*/
*newSlot = NULL;
tuple.t_self = *tid;
ltrmark:;
test = heap_mark4update(relation, &tuple, &buffer, cid);
test = heap_lock_tuple(relation, &tuple, &buffer, cid, LockTupleExclusive);
switch (test)
{
case HeapTupleSelfUpdated:
@ -1636,8 +1636,7 @@ ltrmark:;
default:
ReleaseBuffer(buffer);
elog(ERROR, "unrecognized heap_mark4update status: %u",
test);
elog(ERROR, "invalid heap_lock_tuple status: %d", test);
return NULL; /* keep compiler quiet */
}
}

9
src/backend/commands/vacuum.c
View File

@ -13,7 +13,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/commands/vacuum.c,v 1.306 2005/04/14 20:03:24 tgl Exp $
* $PostgreSQL: pgsql/src/backend/commands/vacuum.c,v 1.307 2005/04/28 21:47:12 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -1800,7 +1800,7 @@ repair_frag(VRelStats *vacrelstats, Relation onerel,
!TransactionIdPrecedes(HeapTupleHeaderGetXmin(tuple.t_data),
OldestXmin)) ||
(!(tuple.t_data->t_infomask & (HEAP_XMAX_INVALID |
HEAP_MARKED_FOR_UPDATE)) &&
HEAP_IS_LOCKED)) &&
!(ItemPointerEquals(&(tuple.t_self),
&(tuple.t_data->t_ctid)))))
{
@ -1839,7 +1839,7 @@ repair_frag(VRelStats *vacrelstats, Relation onerel,
* we have to move to the end of chain.
*/
while (!(tp.t_data->t_infomask & (HEAP_XMAX_INVALID |
HEAP_MARKED_FOR_UPDATE)) &&
HEAP_IS_LOCKED)) &&
!(ItemPointerEquals(&(tp.t_self),
&(tp.t_data->t_ctid))))
{
@ -1984,7 +1984,8 @@ repair_frag(VRelStats *vacrelstats, Relation onerel,
* and we are too close to 6.5 release. - vadim
* 06/11/99
*/
if (!(TransactionIdEquals(HeapTupleHeaderGetXmax(Ptp.t_data),
if (Ptp.t_data->t_infomask & HEAP_XMAX_IS_MULTI ||
!(TransactionIdEquals(HeapTupleHeaderGetXmax(Ptp.t_data),
HeapTupleHeaderGetXmin(tp.t_data))))
{
ReleaseBuffer(Pbuf);

18
src/backend/executor/README
View File

@ -1,4 +1,4 @@
$PostgreSQL: pgsql/src/backend/executor/README,v 1.4 2003/11/29 19:51:48 pgsql Exp $
$PostgreSQL: pgsql/src/backend/executor/README,v 1.5 2005/04/28 21:47:12 tgl Exp $
The Postgres Executor
---------------------
@ -154,8 +154,8 @@ committed by the concurrent transaction (after waiting for it to commit,
if need be) and re-evaluate the query qualifications to see if it would
still meet the quals. If so, we regenerate the updated tuple (if we are
doing an UPDATE) from the modified tuple, and finally update/delete the
modified tuple. SELECT FOR UPDATE behaves similarly, except that its action
is just to mark the modified tuple for update by the current transaction.
modified tuple. SELECT FOR UPDATE/SHARE behaves similarly, except that its
action is just to lock the modified tuple.
To implement this checking, we actually re-run the entire query from scratch
for each modified tuple, but with the scan node that sourced the original
@ -184,14 +184,14 @@ that while we are executing a recheck query for one modified tuple, we will
hit another modified tuple in another relation. In this case we "stack up"
recheck queries: a sub-recheck query is spawned in which both the first and
second modified tuples will be returned as the only components of their
relations. (In event of success, all these modified tuples will be marked
for update.) Again, this isn't necessarily quite the right thing ... but in
simple cases it works. Potentially, recheck queries could get nested to the
depth of the number of FOR UPDATE relations in the query.
relations. (In event of success, all these modified tuples will be locked.)
Again, this isn't necessarily quite the right thing ... but in simple cases
it works. Potentially, recheck queries could get nested to the depth of the
number of FOR UPDATE/SHARE relations in the query.
It should be noted also that UPDATE/DELETE expect at most one tuple to
result from the modified query, whereas in the FOR UPDATE case it's possible
for multiple tuples to result (since we could be dealing with a join in
which multiple tuples join to the modified tuple). We want FOR UPDATE to
mark all relevant tuples, so we pass all tuples output by all the stacked
recheck queries back to the executor toplevel for marking.
lock all relevant tuples, so we pass all tuples output by all the stacked
recheck queries back to the executor toplevel for locking.

28
src/backend/executor/execMain.c
View File

@ -26,7 +26,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/executor/execMain.c,v 1.246 2005/04/14 01:38:17 tgl Exp $
* $PostgreSQL: pgsql/src/backend/executor/execMain.c,v 1.247 2005/04/28 21:47:12 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -560,9 +560,10 @@ InitPlan(QueryDesc *queryDesc, bool explainOnly)
}
/*
* Have to lock relations selected for update
* Have to lock relations selected FOR UPDATE/FOR SHARE
*/
estate->es_rowMark = NIL;
estate->es_forUpdate = parseTree->forUpdate;
if (parseTree->rowMarks != NIL)
{
ListCell *l;
@ -986,7 +987,7 @@ ExecEndPlan(PlanState *planstate, EState *estate)
heap_close(estate->es_into_relation_descriptor, NoLock);
/*
* close any relations selected FOR UPDATE, again keeping locks
* close any relations selected FOR UPDATE/FOR SHARE, again keeping locks
*/
foreach(l, estate->es_rowMark)
{
@ -1126,6 +1127,9 @@ lnext: ;
* ctid!! */
tupleid = &tuple_ctid;
}
/*
* Process any FOR UPDATE or FOR SHARE locking requested.
*/
else if (estate->es_rowMark != NIL)
{
ListCell *l;
@ -1137,6 +1141,7 @@ lnext: ;
Buffer buffer;
HeapTupleData tuple;
TupleTableSlot *newSlot;
LockTupleMode lockmode;
HTSU_Result test;
if (!ExecGetJunkAttribute(junkfilter,
@ -1151,9 +1156,15 @@ lnext: ;
if (isNull)
elog(ERROR, "\"%s\" is NULL", erm->resname);
if (estate->es_forUpdate)
lockmode = LockTupleExclusive;
else
lockmode = LockTupleShared;
tuple.t_self = *((ItemPointer) DatumGetPointer(datum));
test = heap_mark4update(erm->relation, &tuple, &buffer,
estate->es_snapshot->curcid);
test = heap_lock_tuple(erm->relation, &tuple, &buffer,
estate->es_snapshot->curcid,
lockmode);
ReleaseBuffer(buffer);
switch (test)
{
@ -1189,7 +1200,7 @@ lnext: ;
goto lnext;
default:
elog(ERROR, "unrecognized heap_mark4update status: %u",
elog(ERROR, "unrecognized heap_lock_tuple status: %u",
test);
return (NULL);
}
@ -1574,8 +1585,8 @@ ExecUpdate(TupleTableSlot *slot,
* If we generate a new candidate tuple after EvalPlanQual testing, we
* must loop back here and recheck constraints. (We don't need to
* redo triggers, however. If there are any BEFORE triggers then
* trigger.c will have done mark4update to lock the correct tuple, so
* there's no need to do them again.)
* trigger.c will have done heap_lock_tuple to lock the correct tuple,
* so there's no need to do them again.)
*/
lreplace:;
if (resultRelationDesc->rd_att->constr)
@ -2088,6 +2099,7 @@ EvalPlanQualStart(evalPlanQual *epq, EState *estate, evalPlanQual *priorepq)
epqstate->es_param_exec_vals = (ParamExecData *)
palloc0(estate->es_topPlan->nParamExec * sizeof(ParamExecData));
epqstate->es_rowMark = estate->es_rowMark;
epqstate->es_forUpdate = estate->es_forUpdate;
epqstate->es_instrument = estate->es_instrument;
epqstate->es_select_into = estate->es_select_into;
epqstate->es_into_oids = estate->es_into_oids;

3
src/backend/executor/execUtils.c
View File

@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/executor/execUtils.c,v 1.122 2005/04/23 21:32:34 tgl Exp $
* $PostgreSQL: pgsql/src/backend/executor/execUtils.c,v 1.123 2005/04/28 21:47:12 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -198,6 +198,7 @@ CreateExecutorState(void)
estate->es_processed = 0;
estate->es_lastoid = InvalidOid;
estate->es_rowMark = NIL;
estate->es_forUpdate = false;
estate->es_instrument = false;
estate->es_select_into = false;

6
src/backend/nodes/copyfuncs.c
View File

@ -15,7 +15,7 @@
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/nodes/copyfuncs.c,v 1.303 2005/04/25 01:30:13 tgl Exp $
* $PostgreSQL: pgsql/src/backend/nodes/copyfuncs.c,v 1.304 2005/04/28 21:47:12 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -1605,6 +1605,7 @@ _copyQuery(Query *from)
COPY_NODE_FIELD(rtable);
COPY_NODE_FIELD(jointree);
COPY_NODE_FIELD(rowMarks);
COPY_SCALAR_FIELD(forUpdate);
COPY_NODE_FIELD(targetList);
COPY_NODE_FIELD(groupClause);
COPY_NODE_FIELD(havingQual);
@ -1685,7 +1686,8 @@ _copySelectStmt(SelectStmt *from)
COPY_NODE_FIELD(sortClause);
COPY_NODE_FIELD(limitOffset);
COPY_NODE_FIELD(limitCount);
COPY_NODE_FIELD(forUpdate);
COPY_NODE_FIELD(lockedRels);
COPY_SCALAR_FIELD(forUpdate);
COPY_SCALAR_FIELD(op);
COPY_SCALAR_FIELD(all);
COPY_NODE_FIELD(larg);

6
src/backend/nodes/equalfuncs.c
View File

@ -18,7 +18,7 @@
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/nodes/equalfuncs.c,v 1.240 2005/04/07 01:51:38 neilc Exp $
* $PostgreSQL: pgsql/src/backend/nodes/equalfuncs.c,v 1.241 2005/04/28 21:47:12 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -642,6 +642,7 @@ _equalQuery(Query *a, Query *b)
COMPARE_NODE_FIELD(rtable);
COMPARE_NODE_FIELD(jointree);
COMPARE_NODE_FIELD(rowMarks);
COMPARE_SCALAR_FIELD(forUpdate);
COMPARE_NODE_FIELD(targetList);
COMPARE_NODE_FIELD(groupClause);
COMPARE_NODE_FIELD(havingQual);
@ -706,7 +707,8 @@ _equalSelectStmt(SelectStmt *a, SelectStmt *b)
COMPARE_NODE_FIELD(sortClause);
COMPARE_NODE_FIELD(limitOffset);
COMPARE_NODE_FIELD(limitCount);
COMPARE_NODE_FIELD(forUpdate);
COMPARE_NODE_FIELD(lockedRels);
COMPARE_SCALAR_FIELD(forUpdate);
COMPARE_SCALAR_FIELD(op);
COMPARE_SCALAR_FIELD(all);
COMPARE_NODE_FIELD(larg);

6
src/backend/nodes/outfuncs.c
View File

@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/nodes/outfuncs.c,v 1.250 2005/04/25 01:30:13 tgl Exp $
* $PostgreSQL: pgsql/src/backend/nodes/outfuncs.c,v 1.251 2005/04/28 21:47:13 tgl Exp $
*
* NOTES
* Every node type that can appear in stored rules' parsetrees *must*
@ -1268,7 +1268,8 @@ _outSelectStmt(StringInfo str, SelectStmt *node)
WRITE_NODE_FIELD(sortClause);
WRITE_NODE_FIELD(limitOffset);
WRITE_NODE_FIELD(limitCount);
WRITE_NODE_FIELD(forUpdate);
WRITE_NODE_FIELD(lockedRels);
WRITE_BOOL_FIELD(forUpdate);
WRITE_ENUM_FIELD(op, SetOperation);
WRITE_BOOL_FIELD(all);
WRITE_NODE_FIELD(larg);
@ -1385,6 +1386,7 @@ _outQuery(StringInfo str, Query *node)
WRITE_NODE_FIELD(rtable);
WRITE_NODE_FIELD(jointree);
WRITE_NODE_FIELD(rowMarks);
WRITE_BOOL_FIELD(forUpdate);
WRITE_NODE_FIELD(targetList);
WRITE_NODE_FIELD(groupClause);
WRITE_NODE_FIELD(havingQual);

3
src/backend/nodes/readfuncs.c
View File

@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/nodes/readfuncs.c,v 1.176 2005/04/06 16:34:05 tgl Exp $
* $PostgreSQL: pgsql/src/backend/nodes/readfuncs.c,v 1.177 2005/04/28 21:47:13 tgl Exp $
*
* NOTES
* Path and Plan nodes do not have any readfuncs support, because we
@ -145,6 +145,7 @@ _readQuery(void)
READ_NODE_FIELD(rtable);
READ_NODE_FIELD(jointree);
READ_NODE_FIELD(rowMarks);
READ_BOOL_FIELD(forUpdate);
READ_NODE_FIELD(targetList);
READ_NODE_FIELD(groupClause);
READ_NODE_FIELD(havingQual);

8
src/backend/optimizer/path/allpaths.c
View File

@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/optimizer/path/allpaths.c,v 1.128 2005/04/25 01:30:13 tgl Exp $
* $PostgreSQL: pgsql/src/backend/optimizer/path/allpaths.c,v 1.129 2005/04/28 21:47:13 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -214,13 +214,13 @@ set_inherited_rel_pathlist(Query *root, RelOptInfo *rel,
ListCell *il;
/*
* XXX for now, can't handle inherited expansion of FOR UPDATE; can we
* do better?
* XXX for now, can't handle inherited expansion of FOR UPDATE/SHARE;
* can we do better?
*/
if (list_member_int(root->rowMarks, parentRTindex))
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("SELECT FOR UPDATE is not supported for inheritance queries")));
errmsg("SELECT FOR UPDATE/SHARE is not supported for inheritance queries")));
/*
* Initialize to compute size estimates for whole inheritance tree

8
src/backend/optimizer/plan/initsplan.c
View File

@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/optimizer/plan/initsplan.c,v 1.104 2004/12/31 22:00:09 pgsql Exp $
* $PostgreSQL: pgsql/src/backend/optimizer/plan/initsplan.c,v 1.105 2005/04/28 21:47:13 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -323,11 +323,11 @@ mark_baserels_for_outer_join(Query *root, Relids rels, Relids outerrels)
Assert(bms_is_subset(rel->outerjoinset, outerrels));
/*
* Presently the executor cannot support FOR UPDATE marking of
* Presently the executor cannot support FOR UPDATE/SHARE marking of
* rels appearing on the nullable side of an outer join. (It's
* somewhat unclear what that would mean, anyway: what should we
* mark when a result row is generated from no element of the
* nullable relation?) So, complain if target rel is FOR UPDATE.
* nullable relation?) So, complain if target rel is FOR UPDATE/SHARE.
* It's sufficient to make this check once per rel, so do it only
* if rel wasn't already known nullable.
*/
@ -336,7 +336,7 @@ mark_baserels_for_outer_join(Query *root, Relids rels, Relids outerrels)
if (list_member_int(root->rowMarks, relno))
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("SELECT FOR UPDATE cannot be applied to the nullable side of an outer join")));
errmsg("SELECT FOR UPDATE/SHARE cannot be applied to the nullable side of an outer join")));
}
rel->outerjoinset = outerrels;

6
src/backend/optimizer/plan/planner.c
View File

@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/optimizer/plan/planner.c,v 1.184 2005/04/11 23:06:55 tgl Exp $
* $PostgreSQL: pgsql/src/backend/optimizer/plan/planner.c,v 1.185 2005/04/28 21:47:13 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -635,13 +635,13 @@ grouping_planner(Query *parse, double tuple_fraction)
tlist = postprocess_setop_tlist(result_plan->targetlist, tlist);
/*
* Can't handle FOR UPDATE here (parser should have checked
* Can't handle FOR UPDATE/SHARE here (parser should have checked
* already, but let's make sure).
*/
if (parse->rowMarks)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("SELECT FOR UPDATE is not allowed with UNION/INTERSECT/EXCEPT")));
errmsg("SELECT FOR UPDATE/SHARE is not allowed with UNION/INTERSECT/EXCEPT")));
/*
* Calculate pathkeys that represent result ordering requirements

15
src/backend/optimizer/prep/prepjointree.c
View File

@ -16,7 +16,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/optimizer/prep/prepjointree.c,v 1.26 2005/04/06 16:34:06 tgl Exp $
* $PostgreSQL: pgsql/src/backend/optimizer/prep/prepjointree.c,v 1.27 2005/04/28 21:47:14 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -276,11 +276,22 @@ pull_up_subqueries(Query *parse, Node *jtnode, bool below_outer_join)
parse->rtable = list_concat(parse->rtable, subquery->rtable);
/*
* Pull up any FOR UPDATE markers, too. (OffsetVarNodes
* Pull up any FOR UPDATE/SHARE markers, too. (OffsetVarNodes
* already adjusted the marker values, so just list_concat the
* list.)
*
* Executor can't handle multiple FOR UPDATE/SHARE flags, so
* complain if they are valid but different
*/
if (parse->rowMarks && subquery->rowMarks &&
parse->forUpdate != subquery->forUpdate)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot use both FOR UPDATE and FOR SHARE in one query")));
parse->rowMarks = list_concat(parse->rowMarks, subquery->rowMarks);
if (subquery->rowMarks)
parse->forUpdate = subquery->forUpdate;
/*
* We also have to fix the relid sets of any parent

12
src/backend/optimizer/prep/preptlist.c
View File

@ -15,7 +15,7 @@
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/optimizer/prep/preptlist.c,v 1.74 2005/04/06 16:34:06 tgl Exp $
* $PostgreSQL: pgsql/src/backend/optimizer/prep/preptlist.c,v 1.75 2005/04/28 21:47:14 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -102,7 +102,7 @@ preprocess_targetlist(Query *parse, List *tlist)
}
/*
* Add TID targets for rels selected FOR UPDATE. The executor
* Add TID targets for rels selected FOR UPDATE/SHARE. The executor
* uses the TID to know which rows to lock, much as for UPDATE or
* DELETE.
*/
@ -111,22 +111,22 @@ preprocess_targetlist(Query *parse, List *tlist)
ListCell *l;
/*
* We've got trouble if the FOR UPDATE appears inside
* We've got trouble if the FOR UPDATE/SHARE appears inside
* grouping, since grouping renders a reference to individual
* tuple CTIDs invalid. This is also checked at parse time,
* but that's insufficient because of rule substitution, query
* pullup, etc.
*/
CheckSelectForUpdate(parse);
CheckSelectLocking(parse, parse->forUpdate);
/*
* Currently the executor only supports FOR UPDATE at top
* Currently the executor only supports FOR UPDATE/SHARE at top
* level
*/
if (PlannerQueryLevel > 1)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("SELECT FOR UPDATE is not allowed in subqueries")));
errmsg("SELECT FOR UPDATE/SHARE is not allowed in subqueries")));
foreach(l, parse->rowMarks)
{

104
src/backend/parser/analyze.c
View File

@ -6,7 +6,7 @@
* Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/backend/parser/analyze.c,v 1.320 2005/04/14 20:03:24 tgl Exp $
* $PostgreSQL: pgsql/src/backend/parser/analyze.c,v 1.321 2005/04/28 21:47:14 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -134,7 +134,7 @@ static void transformFKConstraints(ParseState *pstate,
bool isAddConstraint);
static void applyColumnNames(List *dst, List *src);
static List *getSetColTypes(ParseState *pstate, Node *node);
static void transformForUpdate(Query *qry, List *forUpdate);
static void transformLocking(Query *qry, List *lockedRels, bool forUpdate);
static void transformConstraintAttrs(List *constraintList);
static void transformColumnType(ParseState *pstate, ColumnDef *column);
static void release_pstate_resources(ParseState *pstate);
@ -1810,8 +1810,8 @@ transformSelectStmt(ParseState *pstate, SelectStmt *stmt)
qry->commandType = CMD_SELECT;
/* make FOR UPDATE clause available to addRangeTableEntry */
pstate->p_forUpdate = stmt->forUpdate;
/* make FOR UPDATE/FOR SHARE list available to addRangeTableEntry */
pstate->p_lockedRels = stmt->lockedRels;
/* process the FROM clause */
transformFromClause(pstate, stmt->fromClause);
@ -1870,8 +1870,8 @@ transformSelectStmt(ParseState *pstate, SelectStmt *stmt)
if (pstate->p_hasAggs || qry->groupClause || qry->havingQual)
parseCheckAggregates(pstate, qry);
if (stmt->forUpdate != NIL)
transformForUpdate(qry, stmt->forUpdate);
if (stmt->lockedRels != NIL)
transformLocking(qry, stmt->lockedRels, stmt->forUpdate);
return qry;
}
@ -1899,7 +1899,8 @@ transformSetOperationStmt(ParseState *pstate, SelectStmt *stmt)
List *sortClause;
Node *limitOffset;
Node *limitCount;
List *forUpdate;
List *lockedRels;
bool forUpdate;
Node *node;
ListCell *left_tlist,
*dtlist;
@ -1937,18 +1938,19 @@ transformSetOperationStmt(ParseState *pstate, SelectStmt *stmt)
sortClause = stmt->sortClause;
limitOffset = stmt->limitOffset;
limitCount = stmt->limitCount;
lockedRels = stmt->lockedRels;
forUpdate = stmt->forUpdate;
stmt->sortClause = NIL;
stmt->limitOffset = NULL;
stmt->limitCount = NULL;
stmt->forUpdate = NIL;
stmt->lockedRels = NIL;
/* We don't support forUpdate with set ops at the moment. */
if (forUpdate)
/* We don't support FOR UPDATE/SHARE with set ops at the moment. */
if (lockedRels)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("SELECT FOR UPDATE is not allowed with UNION/INTERSECT/EXCEPT")));
errmsg("SELECT FOR UPDATE/SHARE is not allowed with UNION/INTERSECT/EXCEPT")));
/*
* Recursively transform the components of the tree.
@ -2083,8 +2085,8 @@ transformSetOperationStmt(ParseState *pstate, SelectStmt *stmt)
if (pstate->p_hasAggs || qry->groupClause || qry->havingQual)
parseCheckAggregates(pstate, qry);
if (forUpdate != NIL)
transformForUpdate(qry, forUpdate);
if (lockedRels != NIL)
transformLocking(qry, lockedRels, forUpdate);
return qry;
}
@ -2107,11 +2109,11 @@ transformSetOperationTree(ParseState *pstate, SelectStmt *stmt)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("INTO is only allowed on first SELECT of UNION/INTERSECT/EXCEPT")));
/* We don't support forUpdate with set ops at the moment. */
if (stmt->forUpdate)
/* We don't support FOR UPDATE/SHARE with set ops at the moment. */
if (stmt->lockedRels)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("SELECT FOR UPDATE is not allowed with UNION/INTERSECT/EXCEPT")));
errmsg("SELECT FOR UPDATE/SHARE is not allowed with UNION/INTERSECT/EXCEPT")));
/*
* If an internal node of a set-op tree has ORDER BY, UPDATE, or LIMIT
@ -2128,7 +2130,7 @@ transformSetOperationTree(ParseState *pstate, SelectStmt *stmt)
{
Assert(stmt->larg != NULL && stmt->rarg != NULL);
if (stmt->sortClause || stmt->limitOffset || stmt->limitCount ||
stmt->forUpdate)
stmt->lockedRels)
isLeaf = true;
else
isLeaf = false;
@ -2711,47 +2713,67 @@ transformExecuteStmt(ParseState *pstate, ExecuteStmt *stmt)
/* exported so planner can check again after rewriting, query pullup, etc */
void
CheckSelectForUpdate(Query *qry)
CheckSelectLocking(Query *qry, bool forUpdate)
{
const char *operation;
if (forUpdate)
operation = "SELECT FOR UPDATE";
else
operation = "SELECT FOR SHARE";
if (qry->setOperations)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("SELECT FOR UPDATE is not allowed with UNION/INTERSECT/EXCEPT")));
/* translator: %s is a SQL command, like SELECT FOR UPDATE */
errmsg("%s is not allowed with UNION/INTERSECT/EXCEPT", operation)));
if (qry->distinctClause != NIL)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("SELECT FOR UPDATE is not allowed with DISTINCT clause")));
/* translator: %s is a SQL command, like SELECT FOR UPDATE */
errmsg("%s is not allowed with DISTINCT clause", operation)));
if (qry->groupClause != NIL)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("SELECT FOR UPDATE is not allowed with GROUP BY clause")));
/* translator: %s is a SQL command, like SELECT FOR UPDATE */
errmsg("%s is not allowed with GROUP BY clause", operation)));
if (qry->havingQual != NULL)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("SELECT FOR UPDATE is not allowed with HAVING clause")));
/* translator: %s is a SQL command, like SELECT FOR UPDATE */
errmsg("%s is not allowed with HAVING clause", operation)));
if (qry->hasAggs)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("SELECT FOR UPDATE is not allowed with aggregate functions")));
/* translator: %s is a SQL command, like SELECT FOR UPDATE */
errmsg("%s is not allowed with aggregate functions", operation)));
}
/*
* Convert FOR UPDATE name list into rowMarks list of integer relids
* Convert FOR UPDATE/SHARE name list into rowMarks list of integer relids
*
* NB: if you need to change this, see also markQueryForUpdate()
* NB: if you need to change this, see also markQueryForLocking()
* in rewriteHandler.c.
*/
static void
transformForUpdate(Query *qry, List *forUpdate)
transformLocking(Query *qry, List *lockedRels, bool forUpdate)
{
List *rowMarks = qry->rowMarks;
List *rowMarks;
ListCell *l;
ListCell *rt;
Index i;
CheckSelectForUpdate(qry);
if (qry->rowMarks && forUpdate != qry->forUpdate)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot use both FOR UPDATE and FOR SHARE in one query")));
qry->forUpdate = forUpdate;
if (linitial(forUpdate) == NULL)
CheckSelectLocking(qry, forUpdate);
rowMarks = qry->rowMarks;
if (linitial(lockedRels) == NULL)
{
/* all regular tables used in query */
i = 0;
@ -2770,10 +2792,11 @@ transformForUpdate(Query *qry, List *forUpdate)
case RTE_SUBQUERY:
/*
* FOR UPDATE of subquery is propagated to subquery's
* rels
* FOR UPDATE/SHARE of subquery is propagated to all
* of subquery's rels
*/
transformForUpdate(rte->subquery, list_make1(NULL));
transformLocking(rte->subquery, list_make1(NULL),
forUpdate);
break;
default:
/* ignore JOIN, SPECIAL, FUNCTION RTEs */
@ -2784,7 +2807,7 @@ transformForUpdate(Query *qry, List *forUpdate)
else
{
/* just the named tables */
foreach(l, forUpdate)
foreach(l, lockedRels)
{
char *relname = strVal(lfirst(l));
@ -2806,25 +2829,26 @@ transformForUpdate(Query *qry, List *forUpdate)
case RTE_SUBQUERY:
/*
* FOR UPDATE of subquery is propagated to
* subquery's rels
* FOR UPDATE/SHARE of subquery is propagated to
* all of subquery's rels
*/
transformForUpdate(rte->subquery, list_make1(NULL));
transformLocking(rte->subquery, list_make1(NULL),
forUpdate);
break;
case RTE_JOIN:
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("SELECT FOR UPDATE cannot be applied to a join")));
errmsg("SELECT FOR UPDATE/SHARE cannot be applied to a join")));
break;
case RTE_SPECIAL:
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("SELECT FOR UPDATE cannot be applied to NEW or OLD")));
errmsg("SELECT FOR UPDATE/SHARE cannot be applied to NEW or OLD")));
break;
case RTE_FUNCTION:
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("SELECT FOR UPDATE cannot be applied to a function")));
errmsg("SELECT FOR UPDATE/SHARE cannot be applied to a function")));
break;
default:
elog(ERROR, "unrecognized RTE type: %d",
@ -2837,7 +2861,7 @@ transformForUpdate(Query *qry, List *forUpdate)
if (rt == NULL)
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_TABLE),
errmsg("relation \"%s\" in FOR UPDATE clause not found in FROM clause",
errmsg("relation \"%s\" in FOR UPDATE/SHARE clause not found in FROM clause",
relname)));
}
}

48
src/backend/parser/gram.y
View File

@ -11,7 +11,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/parser/gram.y,v 2.488 2005/04/23 17:22:16 tgl Exp $
* $PostgreSQL: pgsql/src/backend/parser/gram.y,v 2.489 2005/04/28 21:47:14 tgl Exp $
*
* HISTORY
* AUTHOR DATE MAJOR EVENT
@ -87,7 +87,7 @@ static List *check_func_name(List *names);
static List *extractArgTypes(List *parameters);
static SelectStmt *findLeftmostSelect(SelectStmt *node);
static void insertSelectOptions(SelectStmt *stmt,
List *sortClause, List *forUpdate,
List *sortClause, List *lockingClause,
Node *limitOffset, Node *limitCount);
static Node *makeSetOp(SetOperation op, bool all, Node *larg, Node *rarg);
static Node *doNegate(Node *n);
@ -242,7 +242,8 @@ static void doNegateFloat(Value *v);
%type <oncommit> OnCommitOption
%type <withoids> OptWithOids WithOidsAs
%type <list> for_update_clause opt_for_update_clause update_list
%type <list> for_locking_clause opt_for_locking_clause
update_list
%type <boolean> opt_all
%type <node> join_outer join_qual
@ -4886,9 +4887,9 @@ select_with_parens:
;
/*
* FOR UPDATE may be before or after LIMIT/OFFSET.
* FOR UPDATE/SHARE may be before or after LIMIT/OFFSET.
* In <=7.2.X, LIMIT/OFFSET had to be after FOR UPDATE
* We now support both orderings, but prefer LIMIT/OFFSET before FOR UPDATE
* We now support both orderings, but prefer LIMIT/OFFSET before FOR UPDATE/SHARE
* 2002-08-28 bjm
*/
select_no_parens:
@ -4899,13 +4900,13 @@ select_no_parens:
NULL, NULL);
$$ = $1;
}
| select_clause opt_sort_clause for_update_clause opt_select_limit
| select_clause opt_sort_clause for_locking_clause opt_select_limit
{
insertSelectOptions((SelectStmt *) $1, $2, $3,
list_nth($4, 0), list_nth($4, 1));
$$ = $1;
}
| select_clause opt_sort_clause select_limit opt_for_update_clause
| select_clause opt_sort_clause select_limit opt_for_locking_clause
{
insertSelectOptions((SelectStmt *) $1, $2, $4,
list_nth($3, 0), list_nth($3, 1));
@ -5146,13 +5147,14 @@ having_clause:
| /*EMPTY*/ { $$ = NULL; }
;
for_update_clause:
FOR UPDATE update_list { $$ = $3; }
for_locking_clause:
FOR UPDATE update_list { $$ = lcons(makeString("for_update"), $3); }
| FOR SHARE update_list { $$ = lcons(makeString("for_share"), $3); }
| FOR READ ONLY { $$ = NULL; }
;
opt_for_update_clause:
for_update_clause { $$ = $1; }
opt_for_locking_clause:
for_locking_clause { $$ = $1; }
| /* EMPTY */ { $$ = NULL; }
;
@ -8379,7 +8381,7 @@ findLeftmostSelect(SelectStmt *node)
*/
static void
insertSelectOptions(SelectStmt *stmt,
List *sortClause, List *forUpdate,
List *sortClause, List *lockingClause,
Node *limitOffset, Node *limitCount)
{
/*
@ -8394,13 +8396,27 @@ insertSelectOptions(SelectStmt *stmt,
errmsg("multiple ORDER BY clauses not allowed")));
stmt->sortClause = sortClause;
}
if (forUpdate)
if (lockingClause)
{
if (stmt->forUpdate)
Value *type;
if (stmt->lockedRels)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("multiple FOR UPDATE clauses not allowed")));
stmt->forUpdate = forUpdate;
errmsg("multiple FOR UPDATE/FOR SHARE clauses not allowed")));
Assert(list_length(lockingClause) > 1);
/* 1st is Value node containing "for_update" or "for_share" */
type = (Value *) linitial(lockingClause);
Assert(IsA(type, String));
if (strcmp(strVal(type), "for_update") == 0)
stmt->forUpdate = true;
else if (strcmp(strVal(type), "for_share") == 0)
stmt->forUpdate = false;
else
elog(ERROR, "invalid first node in locking clause");
stmt->lockedRels = list_delete_first(lockingClause);
}
if (limitOffset)
{

18
src/backend/parser/parse_relation.c
View File

@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/parser/parse_relation.c,v 1.106 2005/04/13 16:50:55 tgl Exp $
* $PostgreSQL: pgsql/src/backend/parser/parse_relation.c,v 1.107 2005/04/28 21:47:14 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -40,7 +40,7 @@ static Node *scanNameSpaceForRelid(ParseState *pstate, Node *nsnode,
Oid relid);
static void scanNameSpaceForConflict(ParseState *pstate, Node *nsnode,
RangeTblEntry *rte1, const char *aliasname1);
static bool isForUpdate(ParseState *pstate, char *refname);
static bool isLockedRel(ParseState *pstate, char *refname);
static void expandRelation(Oid relid, Alias *eref,
int rtindex, int sublevels_up,
bool include_dropped,
@ -759,9 +759,9 @@ addRangeTableEntry(ParseState *pstate,
* Get the rel's OID. This access also ensures that we have an
* up-to-date relcache entry for the rel. Since this is typically the
* first access to a rel in a statement, be careful to get the right
* access level depending on whether we're doing SELECT FOR UPDATE.
* access level depending on whether we're doing SELECT FOR UPDATE/SHARE.
*/
lockmode = isForUpdate(pstate, refname) ? RowShareLock : AccessShareLock;
lockmode = isLockedRel(pstate, refname) ? RowShareLock : AccessShareLock;
rel = heap_openrv(relation, lockmode);
rte->relid = RelationGetRelid(rel);
@ -1121,17 +1121,17 @@ addRangeTableEntryForJoin(ParseState *pstate,
}
/*
* Has the specified refname been selected FOR UPDATE?
* Has the specified refname been selected FOR UPDATE/FOR SHARE?
*/
static bool
isForUpdate(ParseState *pstate, char *refname)
isLockedRel(ParseState *pstate, char *refname)
{
/* Outer loop to check parent query levels as well as this one */
while (pstate != NULL)
{
if (pstate->p_forUpdate != NIL)
if (pstate->p_lockedRels != NIL)
{
if (linitial(pstate->p_forUpdate) == NULL)
if (linitial(pstate->p_lockedRels) == NULL)
{
/* all tables used in query */
return true;
@ -1141,7 +1141,7 @@ isForUpdate(ParseState *pstate, char *refname)
/* just the named tables */
ListCell *l;
foreach(l, pstate->p_forUpdate)
foreach(l, pstate->p_lockedRels)
{
char *rname = strVal(lfirst(l));

4
src/backend/parser/parse_type.c
View File

@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/parser/parse_type.c,v 1.73 2004/12/31 22:00:27 pgsql Exp $
* $PostgreSQL: pgsql/src/backend/parser/parse_type.c,v 1.74 2005/04/28 21:47:14 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -432,7 +432,7 @@ parseTypeString(const char *str, Oid *type_id, int32 *typmod)
stmt->sortClause != NIL ||
stmt->limitOffset != NULL ||
stmt->limitCount != NULL ||
stmt->forUpdate != NIL ||
stmt->lockedRels != NIL ||
stmt->op != SETOP_NONE)
goto fail;
if (list_length(stmt->targetList) != 1)

30
src/backend/rewrite/rewriteHandler.c
View File

@ -7,7 +7,7 @@
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/rewrite/rewriteHandler.c,v 1.150 2005/04/06 16:34:06 tgl Exp $
* $PostgreSQL: pgsql/src/backend/rewrite/rewriteHandler.c,v 1.151 2005/04/28 21:47:14 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -51,7 +51,7 @@ static TargetEntry *process_matched_tle(TargetEntry *src_tle,
TargetEntry *prior_tle,
const char *attrName);
static Node *get_assignment_input(Node *node);
static void markQueryForUpdate(Query *qry, bool skipOldNew);
static void markQueryForLocking(Query *qry, bool forUpdate, bool skipOldNew);
static List *matchLocks(CmdType event, RuleLock *rulelocks,
int varno, Query *parsetree);
static Query *fireRIRrules(Query *parsetree, List *activeRIRs);
@ -745,40 +745,46 @@ ApplyRetrieveRule(Query *parsetree,
rte->checkAsUser = 0;
/*
* FOR UPDATE of view?
* FOR UPDATE/SHARE of view?
*/
if (list_member_int(parsetree->rowMarks, rt_index))
{
/*
* Remove the view from the list of rels that will actually be
* marked FOR UPDATE by the executor. It will still be access-
* marked FOR UPDATE/SHARE by the executor. It will still be access-
* checked for write access, though.
*/
parsetree->rowMarks = list_delete_int(parsetree->rowMarks, rt_index);
/*
* Set up the view's referenced tables as if FOR UPDATE.
* Set up the view's referenced tables as if FOR UPDATE/SHARE.
*/
markQueryForUpdate(rule_action, true);
markQueryForLocking(rule_action, parsetree->forUpdate, true);
}
return parsetree;
}
/*
* Recursively mark all relations used by a view as FOR UPDATE.
* Recursively mark all relations used by a view as FOR UPDATE/SHARE.
*
* This may generate an invalid query, eg if some sub-query uses an
* aggregate. We leave it to the planner to detect that.
*
* NB: this must agree with the parser's transformForUpdate() routine.
* NB: this must agree with the parser's transformLocking() routine.
*/
static void
markQueryForUpdate(Query *qry, bool skipOldNew)
markQueryForLocking(Query *qry, bool forUpdate, bool skipOldNew)
{
Index rti = 0;
ListCell *l;
if (qry->rowMarks && forUpdate != qry->forUpdate)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot use both FOR UPDATE and FOR SHARE in one query")));
qry->forUpdate = forUpdate;
foreach(l, qry->rtable)
{
RangeTblEntry *rte = (RangeTblEntry *) lfirst(l);
@ -798,8 +804,8 @@ markQueryForUpdate(Query *qry, bool skipOldNew)
}
else if (rte->rtekind == RTE_SUBQUERY)
{
/* FOR UPDATE of subquery is propagated to subquery's rels */
markQueryForUpdate(rte->subquery, false);
/* FOR UPDATE/SHARE of subquery is propagated to subquery's rels */
markQueryForLocking(rte->subquery, forUpdate, false);
}
}
}
@ -911,7 +917,7 @@ fireRIRrules(Query *parsetree, List *activeRIRs)
* If the relation is the query's result relation, then
* RewriteQuery() already got the right lock on it, so we need no
* additional lock. Otherwise, check to see if the relation is
* accessed FOR UPDATE or not.
* accessed FOR UPDATE/SHARE or not.
*/
if (rt_index == parsetree->resultRelation)
lockmode = NoLock;

5
src/backend/storage/ipc/ipci.c
View File

@ -8,13 +8,14 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/storage/ipc/ipci.c,v 1.74 2004/12/31 22:00:56 pgsql Exp $
* $PostgreSQL: pgsql/src/backend/storage/ipc/ipci.c,v 1.75 2005/04/28 21:47:15 tgl Exp $
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include "access/clog.h"
#include "access/multixact.h"
#include "access/subtrans.h"
#include "access/xlog.h"
#include "miscadmin.h"
@ -75,6 +76,7 @@ CreateSharedMemoryAndSemaphores(bool makePrivate,
size += XLOGShmemSize();
size += CLOGShmemSize();
size += SUBTRANSShmemSize();
size += MultiXactShmemSize();
size += LWLockShmemSize();
size += SInvalShmemSize(maxBackends);
size += FreeSpaceShmemSize();
@ -140,6 +142,7 @@ CreateSharedMemoryAndSemaphores(bool makePrivate,
XLOGShmemInit();
CLOGShmemInit();
SUBTRANSShmemInit();
MultiXactShmemInit();
InitBufferPool();
/*

8
src/backend/storage/lmgr/lwlock.c
View File

@ -15,7 +15,7 @@
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/storage/lmgr/lwlock.c,v 1.27 2005/04/08 14:18:35 tgl Exp $
* $PostgreSQL: pgsql/src/backend/storage/lmgr/lwlock.c,v 1.28 2005/04/28 21:47:15 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -114,6 +114,12 @@ NumLWLocks(void)
/* subtrans.c needs one per SubTrans buffer */
numLocks += NUM_SLRU_BUFFERS;
/*
* multixact.c needs one per MultiXact buffer, but there are
* two SLRU areas for MultiXact
*/
numLocks += 2 * NUM_SLRU_BUFFERS;
/* Perhaps create a few more for use by user-defined modules? */
return numLocks;

11
src/backend/tcop/utility.c
View File

@ -10,7 +10,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/tcop/utility.c,v 1.235 2005/04/14 01:38:18 tgl Exp $
* $PostgreSQL: pgsql/src/backend/tcop/utility.c,v 1.236 2005/04/28 21:47:15 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -238,7 +238,7 @@ QueryIsReadOnly(Query *parsetree)
if (parsetree->into != NULL)
return false; /* SELECT INTO */
else if (parsetree->rowMarks != NIL)
return false; /* SELECT FOR UPDATE */
return false; /* SELECT FOR UPDATE/SHARE */
else
return true;
case CMD_UPDATE:
@ -1663,7 +1663,12 @@ CreateQueryTag(Query *parsetree)
if (parsetree->into != NULL)
tag = "SELECT INTO";
else if (parsetree->rowMarks != NIL)
tag = "SELECT FOR UPDATE";
{
if (parsetree->forUpdate)
tag = "SELECT FOR UPDATE";
else
tag = "SELECT FOR SHARE";
}
else
tag = "SELECT";
break;

26
src/backend/utils/adt/ri_triggers.c
View File

@ -17,7 +17,7 @@
*
* Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
*
* $PostgreSQL: pgsql/src/backend/utils/adt/ri_triggers.c,v 1.76 2004/12/31 22:01:22 pgsql Exp $
* $PostgreSQL: pgsql/src/backend/utils/adt/ri_triggers.c,v 1.77 2005/04/28 21:47:15 tgl Exp $
*
* ----------
*/
@ -206,7 +206,7 @@ RI_FKey_check(PG_FUNCTION_ARGS)
* tuple.
*
* pk_rel is opened in RowShareLock mode since that's what our eventual
* SELECT FOR UPDATE will get on it.
* SELECT FOR SHARE will get on it.
*/
pk_rel = heap_open(trigdata->tg_trigger->tgconstrrelid, RowShareLock);
fk_rel = trigdata->tg_relation;
@ -267,7 +267,7 @@ RI_FKey_check(PG_FUNCTION_ARGS)
* ----------
*/
quoteRelationName(pkrelname, pk_rel);
snprintf(querystr, sizeof(querystr), "SELECT 1 FROM ONLY %s x FOR UPDATE OF x",
snprintf(querystr, sizeof(querystr), "SELECT 1 FROM ONLY %s x FOR SHARE OF x",
pkrelname);
/* Prepare and save the plan */
@ -428,7 +428,7 @@ RI_FKey_check(PG_FUNCTION_ARGS)
queryoids[i] = SPI_gettypeid(fk_rel->rd_att,
qkey.keypair[i][RI_KEYPAIR_FK_IDX]);
}
strcat(querystr, " FOR UPDATE OF x");
strcat(querystr, " FOR SHARE OF x");
/* Prepare and save the plan */
qplan = ri_PlanCheck(querystr, qkey.nkeypairs, queryoids,
@ -590,7 +590,7 @@ ri_Check_Pk_Match(Relation pk_rel, Relation fk_rel,
queryoids[i] = SPI_gettypeid(pk_rel->rd_att,
qkey.keypair[i][RI_KEYPAIR_PK_IDX]);
}
strcat(querystr, " FOR UPDATE OF x");
strcat(querystr, " FOR SHARE OF x");
/* Prepare and save the plan */
qplan = ri_PlanCheck(querystr, qkey.nkeypairs, queryoids,
@ -655,7 +655,7 @@ RI_FKey_noaction_del(PG_FUNCTION_ARGS)
* tuple.
*
* fk_rel is opened in RowShareLock mode since that's what our eventual
* SELECT FOR UPDATE will get on it.
* SELECT FOR SHARE will get on it.
*/
fk_rel = heap_open(trigdata->tg_trigger->tgconstrrelid, RowShareLock);
pk_rel = trigdata->tg_relation;
@ -748,7 +748,7 @@ RI_FKey_noaction_del(PG_FUNCTION_ARGS)
queryoids[i] = SPI_gettypeid(pk_rel->rd_att,
qkey.keypair[i][RI_KEYPAIR_PK_IDX]);
}
strcat(querystr, " FOR UPDATE OF x");
strcat(querystr, " FOR SHARE OF x");
/* Prepare and save the plan */
qplan = ri_PlanCheck(querystr, qkey.nkeypairs, queryoids,
@ -834,7 +834,7 @@ RI_FKey_noaction_upd(PG_FUNCTION_ARGS)
* and old tuple.
*
* fk_rel is opened in RowShareLock mode since that's what our eventual
* SELECT FOR UPDATE will get on it.
* SELECT FOR SHARE will get on it.
*/
fk_rel = heap_open(trigdata->tg_trigger->tgconstrrelid, RowShareLock);
pk_rel = trigdata->tg_relation;
@ -939,7 +939,7 @@ RI_FKey_noaction_upd(PG_FUNCTION_ARGS)
queryoids[i] = SPI_gettypeid(pk_rel->rd_att,
qkey.keypair[i][RI_KEYPAIR_PK_IDX]);
}
strcat(querystr, " FOR UPDATE OF x");
strcat(querystr, " FOR SHARE OF x");
/* Prepare and save the plan */
qplan = ri_PlanCheck(querystr, qkey.nkeypairs, queryoids,
@ -1373,7 +1373,7 @@ RI_FKey_restrict_del(PG_FUNCTION_ARGS)
* tuple.
*
* fk_rel is opened in RowShareLock mode since that's what our eventual
* SELECT FOR UPDATE will get on it.
* SELECT FOR SHARE will get on it.
*/
fk_rel = heap_open(trigdata->tg_trigger->tgconstrrelid, RowShareLock);
pk_rel = trigdata->tg_relation;
@ -1453,7 +1453,7 @@ RI_FKey_restrict_del(PG_FUNCTION_ARGS)
queryoids[i] = SPI_gettypeid(pk_rel->rd_att,
qkey.keypair[i][RI_KEYPAIR_PK_IDX]);
}
strcat(querystr, " FOR UPDATE OF x");
strcat(querystr, " FOR SHARE OF x");
/* Prepare and save the plan */
qplan = ri_PlanCheck(querystr, qkey.nkeypairs, queryoids,
@ -1543,7 +1543,7 @@ RI_FKey_restrict_upd(PG_FUNCTION_ARGS)
* and old tuple.
*
* fk_rel is opened in RowShareLock mode since that's what our eventual
* SELECT FOR UPDATE will get on it.
* SELECT FOR SHARE will get on it.
*/
fk_rel = heap_open(trigdata->tg_trigger->tgconstrrelid, RowShareLock);
pk_rel = trigdata->tg_relation;
@ -1634,7 +1634,7 @@ RI_FKey_restrict_upd(PG_FUNCTION_ARGS)
queryoids[i] = SPI_gettypeid(pk_rel->rd_att,
qkey.keypair[i][RI_KEYPAIR_PK_IDX]);
}
strcat(querystr, " FOR UPDATE OF x");
strcat(querystr, " FOR SHARE OF x");
/* Prepare and save the plan */
qplan = ri_PlanCheck(querystr, qkey.nkeypairs, queryoids,

162
src/backend/utils/time/tqual.c
View File

@ -16,13 +16,14 @@
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/utils/time/tqual.c,v 1.86 2005/03/20 23:40:27 neilc Exp $
* $PostgreSQL: pgsql/src/backend/utils/time/tqual.c,v 1.87 2005/04/28 21:47:16 tgl Exp $
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include "access/multixact.h"
#include "access/subtrans.h"
#include "storage/sinval.h"
#include "utils/tqual.h"
@ -129,7 +130,12 @@ HeapTupleSatisfiesItself(HeapTupleHeader tuple, Buffer buffer)
if (tuple->t_infomask & HEAP_XMAX_INVALID) /* xid invalid */
return true;
/* deleting subtransaction aborted */
if (tuple->t_infomask & HEAP_IS_LOCKED) /* not deleter */
return true;
Assert(!(tuple->t_infomask & HEAP_XMAX_IS_MULTI));
/* deleting subtransaction aborted? */
if (TransactionIdDidAbort(HeapTupleHeaderGetXmax(tuple)))
{
tuple->t_infomask |= HEAP_XMAX_INVALID;
@ -139,9 +145,6 @@ HeapTupleSatisfiesItself(HeapTupleHeader tuple, Buffer buffer)
Assert(TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetXmax(tuple)));
if (tuple->t_infomask & HEAP_MARKED_FOR_UPDATE)
return true;
return false;
}
else if (!TransactionIdDidCommit(HeapTupleHeaderGetXmin(tuple)))
@ -167,14 +170,21 @@ HeapTupleSatisfiesItself(HeapTupleHeader tuple, Buffer buffer)
if (tuple->t_infomask & HEAP_XMAX_COMMITTED)
{
if (tuple->t_infomask & HEAP_MARKED_FOR_UPDATE)
if (tuple->t_infomask & HEAP_IS_LOCKED)
return true;
return false; /* updated by other */
}
if (tuple->t_infomask & HEAP_XMAX_IS_MULTI)
{
/* MultiXacts are currently only allowed to lock tuples */
Assert(tuple->t_infomask & HEAP_IS_LOCKED);
return true;
}
if (TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetXmax(tuple)))
{
if (tuple->t_infomask & HEAP_MARKED_FOR_UPDATE)
if (tuple->t_infomask & HEAP_IS_LOCKED)
return true;
return false;
}
@ -191,7 +201,7 @@ HeapTupleSatisfiesItself(HeapTupleHeader tuple, Buffer buffer)
/* xmax transaction committed */
if (tuple->t_infomask & HEAP_MARKED_FOR_UPDATE)
if (tuple->t_infomask & HEAP_IS_LOCKED)
{
tuple->t_infomask |= HEAP_XMAX_INVALID;
SetBufferCommitInfoNeedsSave(buffer);
@ -300,7 +310,12 @@ HeapTupleSatisfiesNow(HeapTupleHeader tuple, Buffer buffer)
if (tuple->t_infomask & HEAP_XMAX_INVALID) /* xid invalid */
return true;
/* deleting subtransaction aborted */
if (tuple->t_infomask & HEAP_IS_LOCKED) /* not deleter */
return true;
Assert(!(tuple->t_infomask & HEAP_XMAX_IS_MULTI));
/* deleting subtransaction aborted? */
if (TransactionIdDidAbort(HeapTupleHeaderGetXmax(tuple)))
{
tuple->t_infomask |= HEAP_XMAX_INVALID;
@ -310,9 +325,6 @@ HeapTupleSatisfiesNow(HeapTupleHeader tuple, Buffer buffer)
Assert(TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetXmax(tuple)));
if (tuple->t_infomask & HEAP_MARKED_FOR_UPDATE)
return true;
if (HeapTupleHeaderGetCmax(tuple) >= GetCurrentCommandId())
return true; /* deleted after scan started */
else
@ -341,14 +353,21 @@ HeapTupleSatisfiesNow(HeapTupleHeader tuple, Buffer buffer)
if (tuple->t_infomask & HEAP_XMAX_COMMITTED)
{
if (tuple->t_infomask & HEAP_MARKED_FOR_UPDATE)
if (tuple->t_infomask & HEAP_IS_LOCKED)
return true;
return false;
}
if (tuple->t_infomask & HEAP_XMAX_IS_MULTI)
{
/* MultiXacts are currently only allowed to lock tuples */
Assert(tuple->t_infomask & HEAP_IS_LOCKED);
return true;
}
if (TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetXmax(tuple)))
{
if (tuple->t_infomask & HEAP_MARKED_FOR_UPDATE)
if (tuple->t_infomask & HEAP_IS_LOCKED)
return true;
if (HeapTupleHeaderGetCmax(tuple) >= GetCurrentCommandId())
return true; /* deleted after scan started */
@ -368,7 +387,7 @@ HeapTupleSatisfiesNow(HeapTupleHeader tuple, Buffer buffer)
/* xmax transaction committed */
if (tuple->t_infomask & HEAP_MARKED_FOR_UPDATE)
if (tuple->t_infomask & HEAP_IS_LOCKED)
{
tuple->t_infomask |= HEAP_XMAX_INVALID;
SetBufferCommitInfoNeedsSave(buffer);
@ -454,6 +473,22 @@ HeapTupleSatisfiesToast(HeapTupleHeader tuple, Buffer buffer)
* code, since UPDATE needs to know more than "is it visible?". Also,
* tuples of my own xact are tested against the passed CommandId not
* CurrentCommandId.
*
* The possible return codes are:
*
* HeapTupleInvisible: the tuple didn't exist at all when the scan started,
* e.g. it was created by a later CommandId.
*
* HeapTupleMayBeUpdated: The tuple is valid and visible, so it may be
* updated.
*
* HeapTupleSelfUpdated: The tuple was updated by the current transaction,
* after the current scan started.
*
* HeapTupleUpdated: The tuple was updated by a committed transaction.
*
* HeapTupleBeingUpdated: The tuple is being updated by an in-progress
* transaction other than the current transaction.
*/
HTSU_Result
HeapTupleSatisfiesUpdate(HeapTupleHeader tuple, CommandId curcid,
@ -512,7 +547,12 @@ HeapTupleSatisfiesUpdate(HeapTupleHeader tuple, CommandId curcid,
if (tuple->t_infomask & HEAP_XMAX_INVALID) /* xid invalid */
return HeapTupleMayBeUpdated;
/* deleting subtransaction aborted */
if (tuple->t_infomask & HEAP_IS_LOCKED) /* not deleter */
return HeapTupleMayBeUpdated;
Assert(!(tuple->t_infomask & HEAP_XMAX_IS_MULTI));
/* deleting subtransaction aborted? */
if (TransactionIdDidAbort(HeapTupleHeaderGetXmax(tuple)))
{
tuple->t_infomask |= HEAP_XMAX_INVALID;
@ -522,9 +562,6 @@ HeapTupleSatisfiesUpdate(HeapTupleHeader tuple, CommandId curcid,
Assert(TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetXmax(tuple)));
if (tuple->t_infomask & HEAP_MARKED_FOR_UPDATE)
return HeapTupleMayBeUpdated;
if (HeapTupleHeaderGetCmax(tuple) >= curcid)
return HeapTupleSelfUpdated; /* updated after scan
* started */
@ -555,14 +592,26 @@ HeapTupleSatisfiesUpdate(HeapTupleHeader tuple, CommandId curcid,
if (tuple->t_infomask & HEAP_XMAX_COMMITTED)
{
if (tuple->t_infomask & HEAP_MARKED_FOR_UPDATE)
if (tuple->t_infomask & HEAP_IS_LOCKED)
return HeapTupleMayBeUpdated;
return HeapTupleUpdated; /* updated by other */
}
if (tuple->t_infomask & HEAP_XMAX_IS_MULTI)
{
/* MultiXacts are currently only allowed to lock tuples */
Assert(tuple->t_infomask & HEAP_IS_LOCKED);
if (MultiXactIdIsRunning(HeapTupleHeaderGetXmax(tuple)))
return HeapTupleBeingUpdated;
tuple->t_infomask |= HEAP_XMAX_INVALID;
SetBufferCommitInfoNeedsSave(buffer);
return HeapTupleMayBeUpdated;
}
if (TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetXmax(tuple)))
{
if (tuple->t_infomask & HEAP_MARKED_FOR_UPDATE)
if (tuple->t_infomask & HEAP_IS_LOCKED)
return HeapTupleMayBeUpdated;
if (HeapTupleHeaderGetCmax(tuple) >= curcid)
return HeapTupleSelfUpdated; /* updated after scan
@ -585,7 +634,7 @@ HeapTupleSatisfiesUpdate(HeapTupleHeader tuple, CommandId curcid,
/* xmax transaction committed */
if (tuple->t_infomask & HEAP_MARKED_FOR_UPDATE)
if (tuple->t_infomask & HEAP_IS_LOCKED)
{
tuple->t_infomask |= HEAP_XMAX_INVALID;
SetBufferCommitInfoNeedsSave(buffer);
@ -669,7 +718,12 @@ HeapTupleSatisfiesDirty(HeapTupleHeader tuple, Buffer buffer)
if (tuple->t_infomask & HEAP_XMAX_INVALID) /* xid invalid */
return true;
/* deleting subtransaction aborted */
if (tuple->t_infomask & HEAP_IS_LOCKED) /* not deleter */
return true;
Assert(!(tuple->t_infomask & HEAP_XMAX_IS_MULTI));
/* deleting subtransaction aborted? */
if (TransactionIdDidAbort(HeapTupleHeaderGetXmax(tuple)))
{
tuple->t_infomask |= HEAP_XMAX_INVALID;
@ -679,9 +733,6 @@ HeapTupleSatisfiesDirty(HeapTupleHeader tuple, Buffer buffer)
Assert(TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetXmax(tuple)));
if (tuple->t_infomask & HEAP_MARKED_FOR_UPDATE)
return true;
return false;
}
else if (!TransactionIdDidCommit(HeapTupleHeaderGetXmin(tuple)))
@ -710,15 +761,22 @@ HeapTupleSatisfiesDirty(HeapTupleHeader tuple, Buffer buffer)
if (tuple->t_infomask & HEAP_XMAX_COMMITTED)
{
if (tuple->t_infomask & HEAP_MARKED_FOR_UPDATE)
if (tuple->t_infomask & HEAP_IS_LOCKED)
return true;
SnapshotDirty->tid = tuple->t_ctid;
return false; /* updated by other */
}
if (tuple->t_infomask & HEAP_XMAX_IS_MULTI)
{
/* MultiXacts are currently only allowed to lock tuples */
Assert(tuple->t_infomask & HEAP_IS_LOCKED);
return true;
}
if (TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetXmax(tuple)))
{
if (tuple->t_infomask & HEAP_MARKED_FOR_UPDATE)
if (tuple->t_infomask & HEAP_IS_LOCKED)
return true;
return false;
}
@ -738,7 +796,7 @@ HeapTupleSatisfiesDirty(HeapTupleHeader tuple, Buffer buffer)
/* xmax transaction committed */
if (tuple->t_infomask & HEAP_MARKED_FOR_UPDATE)
if (tuple->t_infomask & HEAP_IS_LOCKED)
{
tuple->t_infomask |= HEAP_XMAX_INVALID;
SetBufferCommitInfoNeedsSave(buffer);
@ -828,7 +886,12 @@ HeapTupleSatisfiesSnapshot(HeapTupleHeader tuple, Snapshot snapshot,
if (tuple->t_infomask & HEAP_XMAX_INVALID) /* xid invalid */
return true;
/* deleting subtransaction aborted */
if (tuple->t_infomask & HEAP_IS_LOCKED) /* not deleter */
return true;
Assert(!(tuple->t_infomask & HEAP_XMAX_IS_MULTI));
/* deleting subtransaction aborted? */
/* FIXME -- is this correct w.r.t. the cmax of the tuple? */
if (TransactionIdDidAbort(HeapTupleHeaderGetXmax(tuple)))
{
@ -839,9 +902,6 @@ HeapTupleSatisfiesSnapshot(HeapTupleHeader tuple, Snapshot snapshot,
Assert(TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetXmax(tuple)));
if (tuple->t_infomask & HEAP_MARKED_FOR_UPDATE)
return true;
if (HeapTupleHeaderGetCmax(tuple) >= snapshot->curcid)
return true; /* deleted after scan started */
else
@ -902,9 +962,16 @@ HeapTupleSatisfiesSnapshot(HeapTupleHeader tuple, Snapshot snapshot,
if (tuple->t_infomask & HEAP_XMAX_INVALID) /* xid invalid or aborted */
return true;
if (tuple->t_infomask & HEAP_MARKED_FOR_UPDATE)
if (tuple->t_infomask & HEAP_IS_LOCKED)
return true;
if (tuple->t_infomask & HEAP_XMAX_IS_MULTI)
{
/* MultiXacts are currently only allowed to lock tuples */
Assert(tuple->t_infomask & HEAP_IS_LOCKED);
return true;
}
if (!(tuple->t_infomask & HEAP_XMAX_COMMITTED))
{
if (TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetXmax(tuple)))
@ -1043,7 +1110,7 @@ HeapTupleSatisfiesVacuum(HeapTupleHeader tuple, TransactionId OldestXmin,
{
if (tuple->t_infomask & HEAP_XMAX_INVALID) /* xid invalid */
return HEAPTUPLE_INSERT_IN_PROGRESS;
if (tuple->t_infomask & HEAP_MARKED_FOR_UPDATE)
if (tuple->t_infomask & HEAP_IS_LOCKED)
return HEAPTUPLE_INSERT_IN_PROGRESS;
/* inserted and then deleted by same xact */
return HEAPTUPLE_DELETE_IN_PROGRESS;
@ -1074,22 +1141,30 @@ HeapTupleSatisfiesVacuum(HeapTupleHeader tuple, TransactionId OldestXmin,
if (tuple->t_infomask & HEAP_XMAX_INVALID)
return HEAPTUPLE_LIVE;
if (tuple->t_infomask & HEAP_MARKED_FOR_UPDATE)
if (tuple->t_infomask & HEAP_IS_LOCKED)
{
/*
* "Deleting" xact really only marked it for update, so the tuple
* "Deleting" xact really only locked it, so the tuple
* is live in any case. However, we must make sure that either
* XMAX_COMMITTED or XMAX_INVALID gets set once the xact is gone;
* otherwise it is unsafe to recycle CLOG status after vacuuming.
*/
if (!(tuple->t_infomask & HEAP_XMAX_COMMITTED))
{
if (TransactionIdIsInProgress(HeapTupleHeaderGetXmax(tuple)))
return HEAPTUPLE_LIVE;
if (tuple->t_infomask & HEAP_XMAX_IS_MULTI)
{
if (MultiXactIdIsRunning(HeapTupleHeaderGetXmax(tuple)))
return HEAPTUPLE_LIVE;
}
else
{
if (TransactionIdIsInProgress(HeapTupleHeaderGetXmax(tuple)))
return HEAPTUPLE_LIVE;
}
/*
* We don't really care whether xmax did commit, abort or
* crash. We know that xmax did mark the tuple for update, but
* crash. We know that xmax did lock the tuple, but
* it did not and will never actually update it.
*/
tuple->t_infomask |= HEAP_XMAX_INVALID;
@ -1098,6 +1173,13 @@ HeapTupleSatisfiesVacuum(HeapTupleHeader tuple, TransactionId OldestXmin,
return HEAPTUPLE_LIVE;
}
if (tuple->t_infomask & HEAP_XMAX_IS_MULTI)
{
/* MultiXacts are currently only allowed to lock tuples */
Assert(tuple->t_infomask & HEAP_IS_LOCKED);
return HEAPTUPLE_LIVE;
}
if (!(tuple->t_infomask & HEAP_XMAX_COMMITTED))
{
if (TransactionIdIsInProgress(HeapTupleHeaderGetXmax(tuple)))

6
src/bin/initdb/initdb.c
View File

@ -39,7 +39,7 @@
* Portions Copyright (c) 1994, Regents of the University of California
* Portions taken from FreeBSD.
*
* $PostgreSQL: pgsql/src/bin/initdb/initdb.c,v 1.81 2005/04/12 19:29:24 tgl Exp $
* $PostgreSQL: pgsql/src/bin/initdb/initdb.c,v 1.82 2005/04/28 21:47:16 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -527,7 +527,7 @@ mkdir_p(char *path, mode_t omode)
{
/*
* POSIX 1003.2: For each dir operand that does not name an
* existing directory, effects equivalent to those cased by
* existing directory, effects equivalent to those caused by
* the following command shall occcur:
*
* mkdir -p -m $(umask -S),u+wx $(dirname dir) && mkdir [-m mode]
@ -2124,6 +2124,8 @@ main(int argc, char *argv[])
"pg_xlog/archive_status",
"pg_clog",
"pg_subtrans",
"pg_multixact/members",
"pg_multixact/offsets",
"base",
"base/1",
"pg_tblspc"

3
src/bin/pg_controldata/pg_controldata.c
View File

@ -6,7 +6,7 @@
* copyright (c) Oliver Elphick <olly@lfix.co.uk>, 2001;
* licence: BSD
*
* $PostgreSQL: pgsql/src/bin/pg_controldata/pg_controldata.c,v 1.22 2005/03/29 03:01:32 tgl Exp $
* $PostgreSQL: pgsql/src/bin/pg_controldata/pg_controldata.c,v 1.23 2005/04/28 21:47:16 tgl Exp $
*/
#include "postgres.h"
@ -165,6 +165,7 @@ main(int argc, char *argv[])
printf(_("Latest checkpoint's TimeLineID: %u\n"), ControlFile.checkPointCopy.ThisTimeLineID);
printf(_("Latest checkpoint's NextXID: %u\n"), ControlFile.checkPointCopy.nextXid);
printf(_("Latest checkpoint's NextOID: %u\n"), ControlFile.checkPointCopy.nextOid);
printf(_("Latest checkpoint's NextMultiXactId: %u\n"), ControlFile.checkPointCopy.nextMulti);
printf(_("Time of latest checkpoint: %s\n"), ckpttime_str);
printf(_("Database block size: %u\n"), ControlFile.blcksz);
printf(_("Blocks per segment of large relation: %u\n"), ControlFile.relseg_size);

27
src/bin/pg_resetxlog/pg_resetxlog.c
View File

@ -23,7 +23,7 @@
* Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/bin/pg_resetxlog/pg_resetxlog.c,v 1.31 2005/04/13 18:54:56 tgl Exp $
* $PostgreSQL: pgsql/src/bin/pg_resetxlog/pg_resetxlog.c,v 1.32 2005/04/28 21:47:16 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -40,6 +40,7 @@
#include <getopt.h>
#endif
#include "access/multixact.h"
#include "access/xlog.h"
#include "access/xlog_internal.h"
#include "catalog/catversion.h"
@ -75,6 +76,7 @@ main(int argc, char *argv[])
bool noupdate = false;
TransactionId set_xid = 0;
Oid set_oid = 0;
MultiXactId set_mxid = 0;
uint32 minXlogTli = 0,
minXlogId = 0,
minXlogSeg = 0;
@ -104,7 +106,7 @@ main(int argc, char *argv[])
}
while ((c = getopt(argc, argv, "fl:no:x:")) != -1)
while ((c = getopt(argc, argv, "fl:m:no:x:")) != -1)
{
switch (c)
{
@ -146,6 +148,21 @@ main(int argc, char *argv[])
}
break;
case 'm':
set_mxid = strtoul(optarg, &endptr, 0);
if (endptr == optarg || *endptr != '\0')
{
fprintf(stderr, _("%s: invalid argument for option -m\n"), progname);
fprintf(stderr, _("Try \"%s --help\" for more information.\n"), progname);
exit(1);
}
if (set_mxid == 0)
{
fprintf(stderr, _("%s: multi transaction ID (-m) must not be 0\n"), progname);
exit(1);
}
break;
case 'l':
minXlogTli = strtoul(optarg, &endptr, 0);
if (endptr == optarg || *endptr != ',')
@ -245,6 +262,9 @@ main(int argc, char *argv[])
if (set_oid != 0)
ControlFile.checkPointCopy.nextOid = set_oid;
if (set_mxid != 0)
ControlFile.checkPointCopy.nextMulti = set_mxid;
if (minXlogTli > ControlFile.checkPointCopy.ThisTimeLineID)
ControlFile.checkPointCopy.ThisTimeLineID = minXlogTli;
@ -405,6 +425,7 @@ GuessControlValues(void)
ControlFile.checkPointCopy.ThisTimeLineID = 1;
ControlFile.checkPointCopy.nextXid = (TransactionId) 514; /* XXX */
ControlFile.checkPointCopy.nextOid = FirstBootstrapObjectId;
ControlFile.checkPointCopy.nextMulti = FirstMultiXactId;
ControlFile.checkPointCopy.time = time(NULL);
ControlFile.state = DB_SHUTDOWNED;
@ -478,6 +499,7 @@ PrintControlValues(bool guessed)
printf(_("Latest checkpoint's TimeLineID: %u\n"), ControlFile.checkPointCopy.ThisTimeLineID);
printf(_("Latest checkpoint's NextXID: %u\n"), ControlFile.checkPointCopy.nextXid);
printf(_("Latest checkpoint's NextOID: %u\n"), ControlFile.checkPointCopy.nextOid);
printf(_("Latest checkpoint's NextMultiXactId: %u\n"), ControlFile.checkPointCopy.nextMulti);
printf(_("Database block size: %u\n"), ControlFile.blcksz);
printf(_("Blocks per segment of large relation: %u\n"), ControlFile.relseg_size);
printf(_("Maximum length of identifiers: %u\n"), ControlFile.nameDataLen);
@ -753,6 +775,7 @@ usage(void)
printf(_(" -n no update, just show extracted control values (for testing)\n"));
printf(_(" -o OID set next OID\n"));
printf(_(" -x XID set next transaction ID\n"));
printf(_(" -m multiXID set next multi transaction ID\n"));
printf(_(" --help show this help, then exit\n"));
printf(_(" --version output version information, then exit\n"));
printf(_("\nReport bugs to <pgsql-bugs@postgresql.org>.\n"));

12
src/include/access/heapam.h
View File

@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/include/access/heapam.h,v 1.99 2005/04/14 20:03:27 tgl Exp $
* $PostgreSQL: pgsql/src/include/access/heapam.h,v 1.100 2005/04/28 21:47:16 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -123,6 +123,12 @@ extern Datum fastgetattr(HeapTuple tup, int attnum, TupleDesc tupleDesc,
/* heapam.c */
typedef enum
{
LockTupleShared,
LockTupleExclusive
} LockTupleMode;
extern Relation relation_open(Oid relationId, LOCKMODE lockmode);
extern Relation conditional_relation_open(Oid relationId, LOCKMODE lockmode, bool nowait);
extern Relation relation_openrv(const RangeVar *relation, LOCKMODE lockmode);
@ -155,8 +161,8 @@ extern HTSU_Result heap_delete(Relation relation, ItemPointer tid, ItemPointer c
CommandId cid, Snapshot crosscheck, bool wait);
extern HTSU_Result heap_update(Relation relation, ItemPointer otid, HeapTuple tup,
ItemPointer ctid, CommandId cid, Snapshot crosscheck, bool wait);
extern HTSU_Result heap_mark4update(Relation relation, HeapTuple tup,
Buffer *userbuf, CommandId cid);
extern HTSU_Result heap_lock_tuple(Relation relation, HeapTuple tup,
Buffer *userbuf, CommandId cid, LockTupleMode mode);
extern Oid simple_heap_insert(Relation relation, HeapTuple tup);
extern void simple_heap_delete(Relation relation, ItemPointer tid);

28
src/include/access/htup.h
View File

@ -1,4 +1,4 @@
/*-------------------------------------------------------------------------
/*-------------------------------------------------------------------------
*
* htup.h
* POSTGRES heap tuple definitions.
@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/include/access/htup.h,v 1.73 2005/03/28 01:50:34 tgl Exp $
* $PostgreSQL: pgsql/src/include/access/htup.h,v 1.74 2005/04/28 21:47:17 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -93,11 +93,11 @@ typedef struct HeapTupleFields
{
TransactionId t_xmin; /* inserting xact ID */
CommandId t_cmin; /* inserting command ID */
TransactionId t_xmax; /* deleting xact ID */
TransactionId t_xmax; /* deleting or locking xact ID */
union
{
CommandId t_cmax; /* deleting command ID */
CommandId t_cmax; /* deleting or locking command ID */
TransactionId t_xvac; /* VACUUM FULL xact ID */
} t_field4;
} HeapTupleFields;
@ -152,12 +152,16 @@ typedef HeapTupleHeaderData *HeapTupleHeader;
* attribute(s) */
#define HEAP_HASEXTENDED 0x000C /* the two above combined */
#define HEAP_HASOID 0x0010 /* has an object-id field */
/* 0x0020, 0x0040 and 0x0080 are unused */
/* 0x0020 is presently unused */
#define HEAP_XMAX_EXCL_LOCK 0x0040 /* xmax is exclusive locker */
#define HEAP_XMAX_SHARED_LOCK 0x0080 /* xmax is shared locker */
/* if either LOCK bit is set, xmax hasn't deleted the tuple, only locked it */
#define HEAP_IS_LOCKED (HEAP_XMAX_EXCL_LOCK | HEAP_XMAX_SHARED_LOCK)
#define HEAP_XMIN_COMMITTED 0x0100 /* t_xmin committed */
#define HEAP_XMIN_INVALID 0x0200 /* t_xmin invalid/aborted */
#define HEAP_XMAX_COMMITTED 0x0400 /* t_xmax committed */
#define HEAP_XMAX_INVALID 0x0800 /* t_xmax invalid/aborted */
#define HEAP_MARKED_FOR_UPDATE 0x1000 /* marked for UPDATE */
#define HEAP_XMAX_IS_MULTI 0x1000 /* t_xmax is a MultiXactId */
#define HEAP_UPDATED 0x2000 /* this is UPDATEd version of row */
#define HEAP_MOVED_OFF 0x4000 /* moved to another place by
* VACUUM FULL */
@ -406,7 +410,8 @@ typedef HeapTupleData *HeapTuple;
#define XLOG_HEAP_MOVE 0x30
#define XLOG_HEAP_CLEAN 0x40
#define XLOG_HEAP_NEWPAGE 0x50
/* opcodes 0x60, 0x70 still free */
#define XLOG_HEAP_LOCK 0x60
/* opcode 0x70 still free */
#define XLOG_HEAP_OPMASK 0x70
/*
* When we insert 1st item on new page in INSERT/UPDATE
@ -496,4 +501,13 @@ typedef struct xl_heap_newpage
#define SizeOfHeapNewpage (offsetof(xl_heap_newpage, blkno) + sizeof(BlockNumber))
/* This is what we need to know about lock */
typedef struct xl_heap_lock
{
xl_heaptid target; /* locked tuple id */
bool shared_lock; /* shared or exclusive row lock? */
} xl_heap_lock;
#define SizeOfHeapLock (offsetof(xl_heap_lock, shared_lock) + sizeof(bool))
#endif /* HTUP_H */

37
src/include/access/multixact.h Normal file
View File

@ -0,0 +1,37 @@
/*
* multixact.h
*
* PostgreSQL multi-transaction-log manager
*
* Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/include/access/multixact.h,v 1.1 2005/04/28 21:47:17 tgl Exp $
*/
#ifndef MULTIXACT_H
#define MULTIXACT_H
#define InvalidMultiXactId ((MultiXactId) 0)
#define FirstMultiXactId ((MultiXactId) 1)
#define MultiXactIdIsValid(multi) ((multi) != InvalidMultiXactId)
extern void MultiXactIdWait(MultiXactId multi);
extern MultiXactId MultiXactIdExpand(MultiXactId multi, bool isMulti,
TransactionId xid);
extern bool MultiXactIdIsRunning(MultiXactId multi);
extern void MultiXactIdSetOldestMember(void);
extern void AtEOXact_MultiXact(void);
extern int MultiXactShmemSize(void);
extern void MultiXactShmemInit(void);
extern void BootStrapMultiXact(void);
extern void StartupMultiXact(void);
extern void ShutdownMultiXact(void);
extern MultiXactId MultiXactGetCheckptMulti(bool is_shutdown);
extern void CheckPointMultiXact(void);
extern void MultiXactSetNextMXact(MultiXactId nextMulti);
extern void MultiXactAdvanceNextMXact(MultiXactId minMulti);
#endif /* MULTIXACT_H */

3
src/include/access/xlog.h
View File

@ -6,7 +6,7 @@
* Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/include/access/xlog.h,v 1.59 2004/12/31 22:03:21 pgsql Exp $
* $PostgreSQL: pgsql/src/include/access/xlog.h,v 1.60 2005/04/28 21:47:17 tgl Exp $
*/
#ifndef XLOG_H
#define XLOG_H
@ -133,6 +133,7 @@ extern void ShutdownXLOG(int code, Datum arg);
extern void InitXLOGAccess(void);
extern void CreateCheckPoint(bool shutdown, bool force);
extern void XLogPutNextOid(Oid nextOid);
extern void XLogPutNextMultiXactId(MultiXactId multi);
extern XLogRecPtr GetRedoRecPtr(void);
#endif /* XLOG_H */

8
src/include/c.h
View File

@ -12,7 +12,7 @@
* Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/include/c.h,v 1.181 2005/03/29 00:17:16 tgl Exp $
* $PostgreSQL: pgsql/src/include/c.h,v 1.182 2005/04/28 21:47:17 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -365,7 +365,8 @@ typedef float float4;
typedef double float8;
/*
* Oid, RegProcedure, TransactionId, SubTransactionId, CommandId, AclId
* Oid, RegProcedure, TransactionId, SubTransactionId, MultiXactId,
* CommandId, AclId
*/
/* typedef Oid is in postgres_ext.h */
@ -384,6 +385,9 @@ typedef uint32 SubTransactionId;
#define InvalidSubTransactionId ((SubTransactionId) 0)
#define TopSubTransactionId ((SubTransactionId) 1)
/* MultiXactId must be equivalent to TransactionId, to fit in t_xmax */
typedef TransactionId MultiXactId;
typedef uint32 CommandId;
#define FirstCommandId ((CommandId) 0)

6
src/include/catalog/pg_control.h
View File

@ -8,7 +8,7 @@
* Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/include/catalog/pg_control.h,v 1.20 2005/03/29 03:01:32 tgl Exp $
* $PostgreSQL: pgsql/src/include/catalog/pg_control.h,v 1.21 2005/04/28 21:47:17 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -22,7 +22,7 @@
/* Version identifier for this pg_control format */
#define PG_CONTROL_VERSION 74
#define PG_CONTROL_VERSION 81
/*
* Body of CheckPoint XLOG records. This is declared here because we keep
@ -39,12 +39,14 @@ typedef struct CheckPoint
TimeLineID ThisTimeLineID; /* current TLI */
TransactionId nextXid; /* next free XID */
Oid nextOid; /* next free OID */
MultiXactId nextMulti; /* next free MultiXactId */
time_t time; /* time stamp of checkpoint */
} CheckPoint;
/* XLOG info values for XLOG rmgr */
#define XLOG_CHECKPOINT_SHUTDOWN 0x00
#define XLOG_CHECKPOINT_ONLINE 0x10
#define XLOG_NEXTMULTI 0x20
#define XLOG_NEXTOID 0x30

3
src/include/nodes/execnodes.h
View File

@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/include/nodes/execnodes.h,v 1.129 2005/04/25 01:30:14 tgl Exp $
* $PostgreSQL: pgsql/src/include/nodes/execnodes.h,v 1.130 2005/04/28 21:47:17 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -318,6 +318,7 @@ typedef struct EState
uint32 es_processed; /* # of tuples processed */
Oid es_lastoid; /* last oid processed (by INSERT) */
List *es_rowMark; /* not good place, but there is no other */
bool es_forUpdate; /* was it FOR UPDATE or FOR SHARE */
bool es_instrument; /* true requests runtime instrumentation */
bool es_select_into; /* true if doing SELECT INTO */

12
src/include/nodes/parsenodes.h
View File

@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/include/nodes/parsenodes.h,v 1.277 2005/04/07 01:51:40 neilc Exp $
* $PostgreSQL: pgsql/src/include/nodes/parsenodes.h,v 1.278 2005/04/28 21:47:17 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -50,7 +50,7 @@ typedef uint32 AclMode; /* a bitmask of privilege bits */
#define N_ACL_RIGHTS 11 /* 1 plus the last 1<<x */
#define ACL_ALL_RIGHTS (-1) /* all-privileges marker in GRANT list */
#define ACL_NO_RIGHTS 0
/* Currently, SELECT ... FOR UPDATE requires UPDATE privileges */
/* Currently, SELECT ... FOR UPDATE/FOR SHARE requires UPDATE privileges */
#define ACL_SELECT_FOR_UPDATE ACL_UPDATE
@ -91,7 +91,10 @@ typedef struct Query
* clauses) */
List *rowMarks; /* integer list of RT indexes of relations
* that are selected FOR UPDATE */
* that are selected FOR UPDATE/SHARE */
bool forUpdate; /* true if rowMarks are FOR UPDATE,
* false if they are FOR SHARE */
List *targetList; /* target list (of TargetEntry) */
@ -688,7 +691,8 @@ typedef struct SelectStmt
List *sortClause; /* sort clause (a list of SortBy's) */
Node *limitOffset; /* # of result tuples to skip */
Node *limitCount; /* # of result tuples to return */
List *forUpdate; /* FOR UPDATE clause */
List *lockedRels; /* FOR UPDATE or FOR SHARE relations */
bool forUpdate; /* true = FOR UPDATE, false = FOR SHARE */
/*
* These fields are used only in upper-level SelectStmts.

4
src/include/parser/analyze.h
View File

@ -6,7 +6,7 @@
* Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/include/parser/analyze.h,v 1.29 2004/12/31 22:03:38 pgsql Exp $
* $PostgreSQL: pgsql/src/include/parser/analyze.h,v 1.30 2005/04/28 21:47:18 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -21,6 +21,6 @@ extern List *parse_analyze_varparams(Node *parseTree, Oid **paramTypes,
int *numParams);
extern List *parse_sub_analyze(Node *parseTree, ParseState *parentParseState);
extern List *analyzeCreateSchemaStmt(CreateSchemaStmt *stmt);
extern void CheckSelectForUpdate(Query *qry);
extern void CheckSelectLocking(Query *qry, bool forUpdate);
#endif /* ANALYZE_H */

4
src/include/parser/parse_node.h
View File

@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/include/parser/parse_node.h,v 1.42 2004/12/31 22:03:38 pgsql Exp $
* $PostgreSQL: pgsql/src/include/parser/parse_node.h,v 1.43 2005/04/28 21:47:18 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -53,7 +53,7 @@ typedef struct ParseState
Oid *p_paramtypes; /* OIDs of types for $n parameter symbols */
int p_numparams; /* allocated size of p_paramtypes[] */
int p_next_resno; /* next targetlist resno to assign */
List *p_forUpdate; /* FOR UPDATE clause, if any (see gram.y) */
List *p_lockedRels; /* FOR UPDATE/SHARE, if any (see gram.y) */
Node *p_value_substitute; /* what to replace VALUE with, if
* any */
bool p_variableparams;

5
src/include/storage/bufpage.h
View File

@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/include/storage/bufpage.h,v 1.64 2005/03/22 06:17:03 tgl Exp $
* $PostgreSQL: pgsql/src/include/storage/bufpage.h,v 1.65 2005/04/28 21:47:18 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -135,8 +135,9 @@ typedef PageHeaderData *PageHeader;
* Page layout version number 0 is for pre-7.3 Postgres releases.
* Releases 7.3 and 7.4 use 1, denoting a new HeapTupleHeader layout.
* Release 8.0 changed the HeapTupleHeader layout again.
* Release 8.1 redefined HeapTupleHeader infomask bits.
*/
#define PG_PAGE_LAYOUT_VERSION 2
#define PG_PAGE_LAYOUT_VERSION 3
/* ----------------------------------------------------------------

4
src/include/storage/lmgr.h
View File

@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/include/storage/lmgr.h,v 1.45 2004/12/31 22:03:42 pgsql Exp $
* $PostgreSQL: pgsql/src/include/storage/lmgr.h,v 1.46 2005/04/28 21:47:18 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -23,7 +23,7 @@
#define NoLock 0
#define AccessShareLock 1 /* SELECT */
#define RowShareLock 2 /* SELECT FOR UPDATE */
#define RowShareLock 2 /* SELECT FOR UPDATE/FOR SHARE */
#define RowExclusiveLock 3 /* INSERT, UPDATE, DELETE */
#define ShareUpdateExclusiveLock 4 /* VACUUM (non-FULL) */
#define ShareLock 5 /* CREATE INDEX */

5
src/include/storage/lwlock.h
View File

@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/include/storage/lwlock.h,v 1.17 2005/03/04 20:21:07 tgl Exp $
* $PostgreSQL: pgsql/src/include/storage/lwlock.h,v 1.18 2005/04/28 21:47:18 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -40,6 +40,9 @@ typedef enum LWLockId
CheckpointStartLock,
CLogControlLock,
SubtransControlLock,
MultiXactGenLock,
MultiXactOffsetControlLock,
MultiXactMemberControlLock,
RelCacheInitLock,
BgWriterCommLock,