Rename some support functions for pgstat* views.

Presently, pgstat_fetch_stat_beentry() accepts a session's backend
ID as its argument, and pgstat_fetch_stat_local_beentry() accepts a
1-based index in an internal array as its argument.  The former is
typically used wherever a user must provide a backend ID, and the
latter is usually used internally when looping over all entries in
the array.  This difference was first introduced by d7e39d72ca.
Before that commit, both functions accepted a 1-based index to the
internal array.

This commit renames these two functions to make it clear whether
they use the backend ID or the 1-based index to look up the entry.
This is preparatory work for a follow-up change that will introduce
a function for looking up a LocalPgBackendStatus using a backend
ID.

Reviewed-by: Ian Barwick, Sami Imseih, Michael Paquier, Robert Haas
Discussion: https://postgr.es/m/CAB8KJ%3Dj-ACb3H4L9a_b3ZG3iCYDW5aEu3WsPAzkm2S7JzS1Few%40mail.gmail.com
Backpatch-through: 16
This commit is contained in:
Nathan Bossart 2023-08-30 14:46:52 -07:00
parent fe39f43352
commit 3d51cb5197
3 changed files with 34 additions and 34 deletions

View File

@ -849,8 +849,8 @@ pgstat_read_current_status(void)
/*
* The BackendStatusArray index is exactly the BackendId of the
* source backend. Note that this means localBackendStatusTable
* is in order by backend_id. pgstat_fetch_stat_beentry() depends
* on that.
* is in order by backend_id. pgstat_get_beentry_by_backend_id()
* depends on that.
*/
localentry->backend_id = i;
BackendIdGetTransactionIds(i,
@ -1073,21 +1073,21 @@ cmp_lbestatus(const void *a, const void *b)
}
/* ----------
* pgstat_fetch_stat_beentry() -
* pgstat_get_beentry_by_backend_id() -
*
* Support function for the SQL-callable pgstat* functions. Returns
* our local copy of the current-activity entry for one backend,
* or NULL if the given beid doesn't identify any known session.
*
* The beid argument is the BackendId of the desired session
* (note that this is unlike pgstat_fetch_stat_local_beentry()).
* (note that this is unlike pgstat_get_local_beentry_by_index()).
*
* NB: caller is responsible for a check if the user is permitted to see
* this info (especially the querystring).
* ----------
*/
PgBackendStatus *
pgstat_fetch_stat_beentry(BackendId beid)
pgstat_get_beentry_by_backend_id(BackendId beid)
{
LocalPgBackendStatus key;
LocalPgBackendStatus *ret;
@ -1111,13 +1111,13 @@ pgstat_fetch_stat_beentry(BackendId beid)
/* ----------
* pgstat_fetch_stat_local_beentry() -
* pgstat_get_local_beentry_by_index() -
*
* Like pgstat_fetch_stat_beentry() but with locally computed additions (like
* xid and xmin values of the backend)
* Like pgstat_get_beentry_by_backend_id() but with locally computed additions
* (like xid and xmin values of the backend)
*
* The beid argument is a 1-based index in the localBackendStatusTable
* (note that this is unlike pgstat_fetch_stat_beentry()).
* The idx argument is a 1-based index in the localBackendStatusTable
* (note that this is unlike pgstat_get_beentry_by_backend_id()).
* Returns NULL if the argument is out of range (no current caller does that).
*
* NB: caller is responsible for a check if the user is permitted to see
@ -1125,14 +1125,14 @@ pgstat_fetch_stat_beentry(BackendId beid)
* ----------
*/
LocalPgBackendStatus *
pgstat_fetch_stat_local_beentry(int beid)
pgstat_get_local_beentry_by_index(int idx)
{
pgstat_read_current_status();
if (beid < 1 || beid > localNumBackends)
if (idx < 1 || idx > localNumBackends)
return NULL;
return &localBackendStatusTable[beid - 1];
return &localBackendStatusTable[idx - 1];
}
@ -1141,7 +1141,7 @@ pgstat_fetch_stat_local_beentry(int beid)
*
* Support function for the SQL-callable pgstat* functions. Returns
* the number of sessions known in the localBackendStatusTable, i.e.
* the maximum 1-based index to pass to pgstat_fetch_stat_local_beentry().
* the maximum 1-based index to pass to pgstat_get_local_beentry_by_index().
* ----------
*/
int

View File

@ -211,7 +211,7 @@ pg_stat_get_backend_idset(PG_FUNCTION_ARGS)
if (fctx[0] <= pgstat_fetch_stat_numbackends())
{
/* do when there is more left to send */
LocalPgBackendStatus *local_beentry = pgstat_fetch_stat_local_beentry(fctx[0]);
LocalPgBackendStatus *local_beentry = pgstat_get_local_beentry_by_index(fctx[0]);
SRF_RETURN_NEXT(funcctx, Int32GetDatum(local_beentry->backend_id));
}
@ -264,7 +264,7 @@ pg_stat_get_progress_info(PG_FUNCTION_ARGS)
bool nulls[PG_STAT_GET_PROGRESS_COLS] = {0};
int i;
local_beentry = pgstat_fetch_stat_local_beentry(curr_backend);
local_beentry = pgstat_get_local_beentry_by_index(curr_backend);
beentry = &local_beentry->backendStatus;
/*
@ -325,7 +325,7 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
const char *wait_event = NULL;
/* Get the next one in the list */
local_beentry = pgstat_fetch_stat_local_beentry(curr_backend);
local_beentry = pgstat_get_local_beentry_by_index(curr_backend);
beentry = &local_beentry->backendStatus;
/* If looking for specific PID, ignore all the others */
@ -672,7 +672,7 @@ pg_stat_get_backend_pid(PG_FUNCTION_ARGS)
int32 beid = PG_GETARG_INT32(0);
PgBackendStatus *beentry;
if ((beentry = pgstat_fetch_stat_beentry(beid)) == NULL)
if ((beentry = pgstat_get_beentry_by_backend_id(beid)) == NULL)
PG_RETURN_NULL();
PG_RETURN_INT32(beentry->st_procpid);
@ -685,7 +685,7 @@ pg_stat_get_backend_dbid(PG_FUNCTION_ARGS)
int32 beid = PG_GETARG_INT32(0);
PgBackendStatus *beentry;
if ((beentry = pgstat_fetch_stat_beentry(beid)) == NULL)
if ((beentry = pgstat_get_beentry_by_backend_id(beid)) == NULL)
PG_RETURN_NULL();
PG_RETURN_OID(beentry->st_databaseid);
@ -698,7 +698,7 @@ pg_stat_get_backend_userid(PG_FUNCTION_ARGS)
int32 beid = PG_GETARG_INT32(0);
PgBackendStatus *beentry;
if ((beentry = pgstat_fetch_stat_beentry(beid)) == NULL)
if ((beentry = pgstat_get_beentry_by_backend_id(beid)) == NULL)
PG_RETURN_NULL();
PG_RETURN_OID(beentry->st_userid);
@ -727,7 +727,7 @@ pg_stat_get_backend_subxact(PG_FUNCTION_ARGS)
BlessTupleDesc(tupdesc);
if ((local_beentry = pgstat_fetch_stat_local_beentry(beid)) != NULL)
if ((local_beentry = pgstat_get_local_beentry_by_index(beid)) != NULL)
{
/* Fill values and NULLs */
values[0] = Int32GetDatum(local_beentry->backend_subxact_count);
@ -752,7 +752,7 @@ pg_stat_get_backend_activity(PG_FUNCTION_ARGS)
char *clipped_activity;
text *ret;
if ((beentry = pgstat_fetch_stat_beentry(beid)) == NULL)
if ((beentry = pgstat_get_beentry_by_backend_id(beid)) == NULL)
activity = "<backend information not available>";
else if (!HAS_PGSTAT_PERMISSIONS(beentry->st_userid))
activity = "<insufficient privilege>";
@ -776,7 +776,7 @@ pg_stat_get_backend_wait_event_type(PG_FUNCTION_ARGS)
PGPROC *proc;
const char *wait_event_type = NULL;
if ((beentry = pgstat_fetch_stat_beentry(beid)) == NULL)
if ((beentry = pgstat_get_beentry_by_backend_id(beid)) == NULL)
wait_event_type = "<backend information not available>";
else if (!HAS_PGSTAT_PERMISSIONS(beentry->st_userid))
wait_event_type = "<insufficient privilege>";
@ -797,7 +797,7 @@ pg_stat_get_backend_wait_event(PG_FUNCTION_ARGS)
PGPROC *proc;
const char *wait_event = NULL;
if ((beentry = pgstat_fetch_stat_beentry(beid)) == NULL)
if ((beentry = pgstat_get_beentry_by_backend_id(beid)) == NULL)
wait_event = "<backend information not available>";
else if (!HAS_PGSTAT_PERMISSIONS(beentry->st_userid))
wait_event = "<insufficient privilege>";
@ -818,7 +818,7 @@ pg_stat_get_backend_activity_start(PG_FUNCTION_ARGS)
TimestampTz result;
PgBackendStatus *beentry;
if ((beentry = pgstat_fetch_stat_beentry(beid)) == NULL)
if ((beentry = pgstat_get_beentry_by_backend_id(beid)) == NULL)
PG_RETURN_NULL();
else if (!HAS_PGSTAT_PERMISSIONS(beentry->st_userid))
@ -844,7 +844,7 @@ pg_stat_get_backend_xact_start(PG_FUNCTION_ARGS)
TimestampTz result;
PgBackendStatus *beentry;
if ((beentry = pgstat_fetch_stat_beentry(beid)) == NULL)
if ((beentry = pgstat_get_beentry_by_backend_id(beid)) == NULL)
PG_RETURN_NULL();
else if (!HAS_PGSTAT_PERMISSIONS(beentry->st_userid))
@ -866,7 +866,7 @@ pg_stat_get_backend_start(PG_FUNCTION_ARGS)
TimestampTz result;
PgBackendStatus *beentry;
if ((beentry = pgstat_fetch_stat_beentry(beid)) == NULL)
if ((beentry = pgstat_get_beentry_by_backend_id(beid)) == NULL)
PG_RETURN_NULL();
else if (!HAS_PGSTAT_PERMISSIONS(beentry->st_userid))
@ -890,7 +890,7 @@ pg_stat_get_backend_client_addr(PG_FUNCTION_ARGS)
char remote_host[NI_MAXHOST];
int ret;
if ((beentry = pgstat_fetch_stat_beentry(beid)) == NULL)
if ((beentry = pgstat_get_beentry_by_backend_id(beid)) == NULL)
PG_RETURN_NULL();
else if (!HAS_PGSTAT_PERMISSIONS(beentry->st_userid))
@ -935,7 +935,7 @@ pg_stat_get_backend_client_port(PG_FUNCTION_ARGS)
char remote_port[NI_MAXSERV];
int ret;
if ((beentry = pgstat_fetch_stat_beentry(beid)) == NULL)
if ((beentry = pgstat_get_beentry_by_backend_id(beid)) == NULL)
PG_RETURN_NULL();
else if (!HAS_PGSTAT_PERMISSIONS(beentry->st_userid))
@ -978,12 +978,12 @@ pg_stat_get_db_numbackends(PG_FUNCTION_ARGS)
Oid dbid = PG_GETARG_OID(0);
int32 result;
int tot_backends = pgstat_fetch_stat_numbackends();
int beid;
int idx;
result = 0;
for (beid = 1; beid <= tot_backends; beid++)
for (idx = 1; idx <= tot_backends; idx++)
{
LocalPgBackendStatus *local_beentry = pgstat_fetch_stat_local_beentry(beid);
LocalPgBackendStatus *local_beentry = pgstat_get_local_beentry_by_index(idx);
if (local_beentry->backendStatus.st_databaseid == dbid)
result++;

View File

@ -333,8 +333,8 @@ extern uint64 pgstat_get_my_query_id(void);
* ----------
*/
extern int pgstat_fetch_stat_numbackends(void);
extern PgBackendStatus *pgstat_fetch_stat_beentry(BackendId beid);
extern LocalPgBackendStatus *pgstat_fetch_stat_local_beentry(int beid);
extern PgBackendStatus *pgstat_get_beentry_by_backend_id(BackendId beid);
extern LocalPgBackendStatus *pgstat_get_local_beentry_by_index(int idx);
extern char *pgstat_clip_activity(const char *raw_activity);