database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-07-05 07:21:24 +03:00
Code Activity

Embedded list interface

Browse Source 
Provide a common implementation of embedded singly-linked and
doubly-linked lists.  "Embedded" in the sense that the nodes'
next/previous pointers exist within some larger struct; this design
choice reduces memory allocation overhead.

Most of the implementation uses inlineable functions (where supported),
for performance.

Some existing uses of both types of lists have been converted to the new
code, for demonstration purposes.  Other uses can (and probably will) be
converted in the future.  Since dllist.c is unused after this conversion,
it has been removed.

Author: Andres Freund
Some tweaks by me
Reviewed by Tom Lane, Peter Geoghegan
This commit is contained in:
Alvaro Herrera
2012-10-16 17:36:30 -03:00
parent f862a326ef
commit a66ee69add
9 changed files with 1080 additions and 531 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
src/backend/lib/Makefile
View File

@ -12,6 +12,6 @@ subdir = src/backend/lib
top_builddir = ../../..
include $(top_builddir)/src/Makefile.global
OBJS = dllist.o stringinfo.o
OBJS = ilist.o stringinfo.o
include $(top_srcdir)/src/backend/common.mk

214
src/backend/lib/dllist.c
View File

@ -1,214 +0,0 @@
/*-------------------------------------------------------------------------
*
* dllist.c
* this is a simple doubly linked list implementation
* the elements of the lists are void*
*
* Portions Copyright (c) 1996-2012, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
* src/backend/lib/dllist.c
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include "lib/dllist.h"
Dllist *
DLNewList(void)
{
Dllist *l;
l = (Dllist *) palloc(sizeof(Dllist));
l->dll_head = NULL;
l->dll_tail = NULL;
return l;
}
void
DLInitList(Dllist *list)
{
list->dll_head = NULL;
list->dll_tail = NULL;
}
/*
* free up a list and all the nodes in it --- but *not* whatever the nodes
* might point to!
*/
void
DLFreeList(Dllist *list)
{
Dlelem *curr;
while ((curr = DLRemHead(list)) != NULL)
pfree(curr);
pfree(list);
}
Dlelem *
DLNewElem(void *val)
{
Dlelem *e;
e = (Dlelem *) palloc(sizeof(Dlelem));
e->dle_next = NULL;
e->dle_prev = NULL;
e->dle_val = val;
e->dle_list = NULL;
return e;
}
void
DLInitElem(Dlelem *e, void *val)
{
e->dle_next = NULL;
e->dle_prev = NULL;
e->dle_val = val;
e->dle_list = NULL;
}
void
DLFreeElem(Dlelem *e)
{
pfree(e);
}
void
DLRemove(Dlelem *e)
{
Dllist *l = e->dle_list;
if (e->dle_prev)
e->dle_prev->dle_next = e->dle_next;
else
{
/* must be the head element */
Assert(e == l->dll_head);
l->dll_head = e->dle_next;
}
if (e->dle_next)
e->dle_next->dle_prev = e->dle_prev;
else
{
/* must be the tail element */
Assert(e == l->dll_tail);
l->dll_tail = e->dle_prev;
}
e->dle_next = NULL;
e->dle_prev = NULL;
e->dle_list = NULL;
}
void
DLAddHead(Dllist *l, Dlelem *e)
{
e->dle_list = l;
if (l->dll_head)
l->dll_head->dle_prev = e;
e->dle_next = l->dll_head;
e->dle_prev = NULL;
l->dll_head = e;
if (l->dll_tail == NULL) /* if this is first element added */
l->dll_tail = e;
}
void
DLAddTail(Dllist *l, Dlelem *e)
{
e->dle_list = l;
if (l->dll_tail)
l->dll_tail->dle_next = e;
e->dle_prev = l->dll_tail;
e->dle_next = NULL;
l->dll_tail = e;
if (l->dll_head == NULL) /* if this is first element added */
l->dll_head = e;
}
Dlelem *
DLRemHead(Dllist *l)
{
/* remove and return the head */
Dlelem *result = l->dll_head;
if (result == NULL)
return result;
if (result->dle_next)
result->dle_next->dle_prev = NULL;
l->dll_head = result->dle_next;
if (result == l->dll_tail) /* if the head is also the tail */
l->dll_tail = NULL;
result->dle_next = NULL;
result->dle_list = NULL;
return result;
}
Dlelem *
DLRemTail(Dllist *l)
{
/* remove and return the tail */
Dlelem *result = l->dll_tail;
if (result == NULL)
return result;
if (result->dle_prev)
result->dle_prev->dle_next = NULL;
l->dll_tail = result->dle_prev;
if (result == l->dll_head) /* if the tail is also the head */
l->dll_head = NULL;
result->dle_prev = NULL;
result->dle_list = NULL;
return result;
}
/* Same as DLRemove followed by DLAddHead, but faster */
void
DLMoveToFront(Dlelem *e)
{
Dllist *l = e->dle_list;
if (l->dll_head == e)
return; /* Fast path if already at front */
Assert(e->dle_prev != NULL); /* since it's not the head */
e->dle_prev->dle_next = e->dle_next;
if (e->dle_next)
e->dle_next->dle_prev = e->dle_prev;
else
{
/* must be the tail element */
Assert(e == l->dll_tail);
l->dll_tail = e->dle_prev;
}
l->dll_head->dle_prev = e;
e->dle_next = l->dll_head;
e->dle_prev = NULL;
l->dll_head = e;
/* We need not check dll_tail, since there must have been > 1 entry */
}

109
src/backend/lib/ilist.c Normal file
View File

@ -0,0 +1,109 @@
/*-------------------------------------------------------------------------
*
* ilist.c
* support for integrated/inline doubly- and singly- linked lists
*
* Portions Copyright (c) 1996-2012, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
* src/backend/lib/ilist.c
*
* NOTES
* This file only contains functions that are too big to be considered
* for inlining. See ilist.h for most of the goodies.
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
/* See ilist.h */
#define ILIST_INCLUDE_DEFINITIONS
#include "lib/ilist.h"
/*
* removes a node from a list
*
* Attention: O(n)
*/
void
slist_delete(slist_head *head, slist_node *node)
{
slist_node *last = &head->head;
slist_node *cur;
bool found PG_USED_FOR_ASSERTS_ONLY = false;
while ((cur = last->next) != NULL)
{
if (cur == node)
{
last->next = cur->next;
#ifdef USE_ASSERT_CHECKING
found = true;
#endif
break;
}
last = cur;
}
slist_check(head);
Assert(found);
}
#ifdef ILIST_DEBUG
/*
* Verify integrity of a doubly linked list
*/
void
dlist_check(dlist_head *head)
{
dlist_node *cur;
if (head == NULL || !(&head->head))
elog(ERROR, "doubly linked list head is not properly initialized");
/* iterate in forward direction */
for (cur = head->head.next; cur != &head->head; cur = cur->next)
{
if (cur == NULL ||
cur->next == NULL ||
cur->prev == NULL ||
cur->prev->next != cur ||
cur->next->prev != cur)
elog(ERROR, "doubly linked list is corrupted");
}
/* iterate in backward direction */
for (cur = head->head.prev; cur != &head->head; cur = cur->prev)
{
if (cur == NULL ||
cur->next == NULL ||
cur->prev == NULL ||
cur->prev->next != cur ||
cur->next->prev != cur)
elog(ERROR, "doubly linked list is corrupted");
}
}
/*
* Verify integrity of a singly linked list
*/
void
slist_check(slist_head *head)
{
slist_node *cur;
if (head == NULL)
elog(ERROR, "singly linked is NULL");
/*
* there isn't much we can test in a singly linked list other that it
* actually ends sometime, i.e. hasn't introduced a cycle or similar
*/
for (cur = head->head.next; cur != NULL; cur = cur->next)
;
}
#endif /* ILIST_DEBUG */

216
src/backend/postmaster/autovacuum.c
View File

@ -77,7 +77,7 @@
#include "catalog/pg_database.h"
#include "commands/dbcommands.h"
#include "commands/vacuum.h"
#include "lib/dllist.h"
#include "lib/ilist.h"
#include "libpq/pqsignal.h"
#include "miscadmin.h"
#include "pgstat.h"
@ -152,6 +152,7 @@ typedef struct avl_dbase
Oid adl_datid; /* hash key -- must be first */
TimestampTz adl_next_worker;
int adl_score;
dlist_node adl_node;
} avl_dbase;
/* struct to keep track of databases in worker */
@ -208,7 +209,7 @@ typedef struct autovac_table
*/
typedef struct WorkerInfoData
{
SHM_QUEUE wi_links;
dlist_node wi_links;
Oid wi_dboid;
Oid wi_tableoid;
PGPROC *wi_proc;
@ -251,15 +252,18 @@ typedef struct
{
sig_atomic_t av_signal[AutoVacNumSignals];
pid_t av_launcherpid;
WorkerInfo av_freeWorkers;
SHM_QUEUE av_runningWorkers;
dlist_head av_freeWorkers;
dlist_head av_runningWorkers;
WorkerInfo av_startingWorker;
} AutoVacuumShmemStruct;
static AutoVacuumShmemStruct *AutoVacuumShmem;
/* the database list in the launcher, and the context that contains it */
static Dllist *DatabaseList = NULL;
/*
* the database list (of avl_dbase elements) in the launcher, and the context
* that contains it
*/
static dlist_head DatabaseList = DLIST_STATIC_INIT(DatabaseList);
static MemoryContext DatabaseListCxt = NULL;
/* Pointer to my own WorkerInfo, valid on each worker */
@ -508,7 +512,7 @@ AutoVacLauncherMain(int argc, char *argv[])
/* don't leave dangling pointers to freed memory */
DatabaseListCxt = NULL;
DatabaseList = NULL;
dlist_init(&DatabaseList);
/*
* Make sure pgstat also considers our stat data as gone. Note: we
@ -576,7 +580,7 @@ AutoVacLauncherMain(int argc, char *argv[])
struct timeval nap;
TimestampTz current_time = 0;
bool can_launch;
Dlelem *elem;
avl_dbase *avdb;
int rc;
/*
@ -586,7 +590,7 @@ AutoVacLauncherMain(int argc, char *argv[])
* wakening conditions.
*/
launcher_determine_sleep((AutoVacuumShmem->av_freeWorkers != NULL),
launcher_determine_sleep(!dlist_is_empty(&AutoVacuumShmem->av_freeWorkers),
false, &nap);
/* Allow sinval catchup interrupts while sleeping */
@ -679,7 +683,7 @@ AutoVacLauncherMain(int argc, char *argv[])
current_time = GetCurrentTimestamp();
LWLockAcquire(AutovacuumLock, LW_SHARED);
can_launch = (AutoVacuumShmem->av_freeWorkers != NULL);
can_launch = !dlist_is_empty(&AutoVacuumShmem->av_freeWorkers);
if (AutoVacuumShmem->av_startingWorker != NULL)
{
@ -721,8 +725,7 @@ AutoVacLauncherMain(int argc, char *argv[])
worker->wi_tableoid = InvalidOid;
worker->wi_proc = NULL;
worker->wi_launchtime = 0;
worker->wi_links.next = (SHM_QUEUE *) AutoVacuumShmem->av_freeWorkers;
AutoVacuumShmem->av_freeWorkers = worker;
dlist_push_head(&AutoVacuumShmem->av_freeWorkers, &worker->wi_links);
AutoVacuumShmem->av_startingWorker = NULL;
elog(WARNING, "worker took too long to start; canceled");
}
@ -738,20 +741,7 @@ AutoVacLauncherMain(int argc, char *argv[])
/* We're OK to start a new worker */
elem = DLGetTail(DatabaseList);
if (elem != NULL)
{
avl_dbase *avdb = DLE_VAL(elem);
/*
* launch a worker if next_worker is right now or it is in the
* past
*/
if (TimestampDifferenceExceeds(avdb->adl_next_worker,
current_time, 0))
launch_worker(current_time);
}
else
if (dlist_is_empty(&DatabaseList))
{
/*
* Special case when the list is empty: start a worker right away.
@ -763,6 +753,23 @@ AutoVacLauncherMain(int argc, char *argv[])
*/
launch_worker(current_time);
}
else
{
/*
* because rebuild_database_list constructs a list with most
* distant adl_next_worker first, we obtain our database from the
* tail of the list.
*/
avdb = dlist_tail_element(avl_dbase, adl_node, &DatabaseList);
/*
* launch a worker if next_worker is right now or it is in the
* past
*/
if (TimestampDifferenceExceeds(avdb->adl_next_worker,
current_time, 0))
launch_worker(current_time);
}
}
/* Normal exit from the autovac launcher is here */
@ -783,7 +790,7 @@ AutoVacLauncherMain(int argc, char *argv[])
static void
launcher_determine_sleep(bool canlaunch, bool recursing, struct timeval * nap)
{
Dlelem *elem;
avl_dbase *avdb;
/*
* We sleep until the next scheduled vacuum. We trust that when the
@ -796,14 +803,15 @@ launcher_determine_sleep(bool canlaunch, bool recursing, struct timeval * nap)
nap->tv_sec = autovacuum_naptime;
nap->tv_usec = 0;
}
else if ((elem = DLGetTail(DatabaseList)) != NULL)
else if (!dlist_is_empty(&DatabaseList))
{
avl_dbase *avdb = DLE_VAL(elem);
TimestampTz current_time = GetCurrentTimestamp();
TimestampTz next_wakeup;
long secs;
int usecs;
avdb = dlist_tail_element(avl_dbase, adl_node, &DatabaseList);
next_wakeup = avdb->adl_next_worker;
TimestampDifference(current_time, next_wakeup, &secs, &usecs);
@ -867,6 +875,7 @@ rebuild_database_list(Oid newdb)
int score;
int nelems;
HTAB *dbhash;
dlist_iter iter;
/* use fresh stats */
autovac_refresh_stats();
@ -927,36 +936,28 @@ rebuild_database_list(Oid newdb)
}
/* Now insert the databases from the existing list */
if (DatabaseList != NULL)
dlist_foreach(iter, &DatabaseList)
{
Dlelem *elem;
avl_dbase *avdb = dlist_container(avl_dbase, adl_node, iter.cur);
avl_dbase *db;
bool found;
PgStat_StatDBEntry *entry;
elem = DLGetHead(DatabaseList);
while (elem != NULL)
/*
* skip databases with no stat entries -- in particular, this gets
* rid of dropped databases
*/
entry = pgstat_fetch_stat_dbentry(avdb->adl_datid);
if (entry == NULL)
continue;
db = hash_search(dbhash, &(avdb->adl_datid), HASH_ENTER, &found);
if (!found)
{
avl_dbase *avdb = DLE_VAL(elem);
avl_dbase *db;
bool found;
PgStat_StatDBEntry *entry;
elem = DLGetSucc(elem);
/*
* skip databases with no stat entries -- in particular, this gets
* rid of dropped databases
*/
entry = pgstat_fetch_stat_dbentry(avdb->adl_datid);
if (entry == NULL)
continue;
db = hash_search(dbhash, &(avdb->adl_datid), HASH_ENTER, &found);
if (!found)
{
/* hash_search already filled in the key */
db->adl_score = score++;
/* next_worker is filled in later */
}
/* hash_search already filled in the key */
db->adl_score = score++;
/* next_worker is filled in later */
}
}
@ -987,7 +988,7 @@ rebuild_database_list(Oid newdb)
/* from here on, the allocated memory belongs to the new list */
MemoryContextSwitchTo(newcxt);
DatabaseList = DLNewList();
dlist_init(&DatabaseList);
if (nelems > 0)
{
@ -1029,15 +1030,13 @@ rebuild_database_list(Oid newdb)
for (i = 0; i < nelems; i++)
{
avl_dbase *db = &(dbary[i]);
Dlelem *elem;
current_time = TimestampTzPlusMilliseconds(current_time,
millis_increment);
db->adl_next_worker = current_time;
elem = DLNewElem(db);
/* later elements should go closer to the head of the list */
DLAddHead(DatabaseList, elem);
dlist_push_head(&DatabaseList, &db->adl_node);
}
}
@ -1086,7 +1085,7 @@ do_start_worker(void)
/* return quickly when there are no free workers */
LWLockAcquire(AutovacuumLock, LW_SHARED);
if (AutoVacuumShmem->av_freeWorkers == NULL)
if (dlist_is_empty(&AutoVacuumShmem->av_freeWorkers))
{
LWLockRelease(AutovacuumLock);
return InvalidOid;
@ -1147,7 +1146,7 @@ do_start_worker(void)
foreach(cell, dblist)
{
avw_dbase *tmp = lfirst(cell);
Dlelem *elem;
dlist_iter iter;
/* Check to see if this one is at risk of wraparound */
if (TransactionIdPrecedes(tmp->adw_frozenxid, xidForceLimit))
@ -1179,11 +1178,10 @@ do_start_worker(void)
* autovacuum time yet.
*/
skipit = false;
elem = DatabaseList ? DLGetTail(DatabaseList) : NULL;
while (elem != NULL)
dlist_reverse_foreach(iter, &DatabaseList)
{
avl_dbase *dbp = DLE_VAL(elem);
avl_dbase *dbp = dlist_container(avl_dbase, adl_node, iter.cur);
if (dbp->adl_datid == tmp->adw_datid)
{
@ -1200,7 +1198,6 @@ do_start_worker(void)
break;
}
elem = DLGetPred(elem);
}
if (skipit)
continue;
@ -1218,20 +1215,17 @@ do_start_worker(void)
if (avdb != NULL)
{
WorkerInfo worker;
dlist_node *wptr;
LWLockAcquire(AutovacuumLock, LW_EXCLUSIVE);
/*
* Get a worker entry from the freelist. We checked above, so there
* really should be a free slot -- complain very loudly if there
* isn't.
* really should be a free slot.
*/
worker = AutoVacuumShmem->av_freeWorkers;
if (worker == NULL)
elog(FATAL, "no free worker found");
AutoVacuumShmem->av_freeWorkers = (WorkerInfo) worker->wi_links.next;
wptr = dlist_pop_head_node(&AutoVacuumShmem->av_freeWorkers);
worker = dlist_container(WorkerInfoData, wi_links, wptr);
worker->wi_dboid = avdb->adw_datid;
worker->wi_proc = NULL;
worker->wi_launchtime = GetCurrentTimestamp();
@ -1274,22 +1268,25 @@ static void
launch_worker(TimestampTz now)
{
Oid dbid;
Dlelem *elem;
dlist_iter iter;
dbid = do_start_worker();
if (OidIsValid(dbid))
{
bool found = false;
/*
* Walk the database list and update the corresponding entry. If the
* database is not on the list, we'll recreate the list.
*/
elem = (DatabaseList == NULL) ? NULL : DLGetHead(DatabaseList);
while (elem != NULL)
dlist_foreach(iter, &DatabaseList)
{
avl_dbase *avdb = DLE_VAL(elem);
avl_dbase *avdb = dlist_container(avl_dbase, adl_node, iter.cur);
if (avdb->adl_datid == dbid)
{
found = true;
/*
* add autovacuum_naptime seconds to the current time, and use
* that as the new "next_worker" field for this database.
@ -1297,10 +1294,9 @@ launch_worker(TimestampTz now)
avdb->adl_next_worker =
TimestampTzPlusMilliseconds(now, autovacuum_naptime * 1000);
DLMoveToFront(elem);
dlist_move_head(&DatabaseList, iter.cur);
break;
}
elem = DLGetSucc(elem);
}
/*
@ -1310,7 +1306,7 @@ launch_worker(TimestampTz now)
* pgstat entry, but this is not a problem because we don't want to
* schedule workers regularly into those in any case.
*/
if (elem == NULL)
if (!found)
rebuild_database_list(dbid);
}
}
@ -1590,8 +1586,8 @@ AutoVacWorkerMain(int argc, char *argv[])
MyWorkerInfo->wi_proc = MyProc;
/* insert into the running list */
SHMQueueInsertBefore(&AutoVacuumShmem->av_runningWorkers,
&MyWorkerInfo->wi_links);
dlist_push_head(&AutoVacuumShmem->av_runningWorkers,
&MyWorkerInfo->wi_links);
/*
* remove from the "starting" pointer, so that the launcher can start
@ -1681,8 +1677,7 @@ FreeWorkerInfo(int code, Datum arg)
*/
AutovacuumLauncherPid = AutoVacuumShmem->av_launcherpid;
SHMQueueDelete(&MyWorkerInfo->wi_links);
MyWorkerInfo->wi_links.next = (SHM_QUEUE *) AutoVacuumShmem->av_freeWorkers;
dlist_delete(&AutoVacuumShmem->av_runningWorkers, &MyWorkerInfo->wi_links);
MyWorkerInfo->wi_dboid = InvalidOid;
MyWorkerInfo->wi_tableoid = InvalidOid;
MyWorkerInfo->wi_proc = NULL;
@ -1690,7 +1685,7 @@ FreeWorkerInfo(int code, Datum arg)
MyWorkerInfo->wi_cost_delay = 0;
MyWorkerInfo->wi_cost_limit = 0;
MyWorkerInfo->wi_cost_limit_base = 0;
AutoVacuumShmem->av_freeWorkers = MyWorkerInfo;
dlist_push_head(&AutoVacuumShmem->av_freeWorkers, &MyWorkerInfo->wi_links);
/* not mine anymore */
MyWorkerInfo = NULL;
@ -1740,7 +1735,7 @@ autovac_balance_cost(void)
autovacuum_vac_cost_delay : VacuumCostDelay);
double cost_total;
double cost_avail;
WorkerInfo worker;
dlist_iter iter;
/* not set? nothing to do */
if (vac_cost_limit <= 0 || vac_cost_delay <= 0)
@ -1748,19 +1743,14 @@ autovac_balance_cost(void)
/* caculate the total base cost limit of active workers */
cost_total = 0.0;
worker = (WorkerInfo) SHMQueueNext(&AutoVacuumShmem->av_runningWorkers,
&AutoVacuumShmem->av_runningWorkers,
offsetof(WorkerInfoData, wi_links));
while (worker)
dlist_foreach(iter, &AutoVacuumShmem->av_runningWorkers)
{
WorkerInfo worker = dlist_container(WorkerInfoData, wi_links, iter.cur);
if (worker->wi_proc != NULL &&
worker->wi_cost_limit_base > 0 && worker->wi_cost_delay > 0)
cost_total +=
(double) worker->wi_cost_limit_base / worker->wi_cost_delay;
worker = (WorkerInfo) SHMQueueNext(&AutoVacuumShmem->av_runningWorkers,
&worker->wi_links,
offsetof(WorkerInfoData, wi_links));
}
/* there are no cost limits -- nothing to do */
if (cost_total <= 0)
@ -1771,11 +1761,10 @@ autovac_balance_cost(void)
* limit to autovacuum_vacuum_cost_limit.
*/
cost_avail = (double) vac_cost_limit / vac_cost_delay;
worker = (WorkerInfo) SHMQueueNext(&AutoVacuumShmem->av_runningWorkers,
&AutoVacuumShmem->av_runningWorkers,
offsetof(WorkerInfoData, wi_links));
while (worker)
dlist_foreach(iter, &AutoVacuumShmem->av_runningWorkers)
{
WorkerInfo worker = dlist_container(WorkerInfoData, wi_links, iter.cur);
if (worker->wi_proc != NULL &&
worker->wi_cost_limit_base > 0 && worker->wi_cost_delay > 0)
{
@ -1797,10 +1786,6 @@ autovac_balance_cost(void)
worker->wi_cost_limit, worker->wi_cost_limit_base,
worker->wi_cost_delay);
}
worker = (WorkerInfo) SHMQueueNext(&AutoVacuumShmem->av_runningWorkers,
&worker->wi_links,
offsetof(WorkerInfoData, wi_links));
}
}
@ -2177,10 +2162,10 @@ do_autovacuum(void)
{
Oid relid = lfirst_oid(cell);
autovac_table *tab;
WorkerInfo worker;
bool skipit;
int stdVacuumCostDelay;
int stdVacuumCostLimit;
dlist_iter iter;
CHECK_FOR_INTERRUPTS();
@ -2197,29 +2182,23 @@ do_autovacuum(void)
* worker.
*/
skipit = false;
worker = (WorkerInfo) SHMQueueNext(&AutoVacuumShmem->av_runningWorkers,
&AutoVacuumShmem->av_runningWorkers,
offsetof(WorkerInfoData, wi_links));
while (worker)
dlist_foreach(iter, &AutoVacuumShmem->av_runningWorkers)
{
WorkerInfo worker = dlist_container(WorkerInfoData, wi_links, iter.cur);
/* ignore myself */
if (worker == MyWorkerInfo)
goto next_worker;
continue;
/* ignore workers in other databases */
if (worker->wi_dboid != MyDatabaseId)
goto next_worker;
continue;
if (worker->wi_tableoid == relid)
{
skipit = true;
break;
}
next_worker:
worker = (WorkerInfo) SHMQueueNext(&AutoVacuumShmem->av_runningWorkers,
&worker->wi_links,
offsetof(WorkerInfoData, wi_links));
}
LWLockRelease(AutovacuumLock);
if (skipit)
@ -2875,8 +2854,8 @@ AutoVacuumShmemInit(void)
Assert(!found);
AutoVacuumShmem->av_launcherpid = 0;
AutoVacuumShmem->av_freeWorkers = NULL;
SHMQueueInit(&AutoVacuumShmem->av_runningWorkers);
dlist_init(&AutoVacuumShmem->av_freeWorkers);
dlist_init(&AutoVacuumShmem->av_runningWorkers);
AutoVacuumShmem->av_startingWorker = NULL;
worker = (WorkerInfo) ((char *) AutoVacuumShmem +
@ -2884,10 +2863,7 @@ AutoVacuumShmemInit(void)
/* initialize the WorkerInfo free list */
for (i = 0; i < autovacuum_max_workers; i++)
{
worker[i].wi_links.next = (SHM_QUEUE *) AutoVacuumShmem->av_freeWorkers;
AutoVacuumShmem->av_freeWorkers = &worker[i];
}
dlist_push_head(&AutoVacuumShmem->av_freeWorkers, &worker[i].wi_links);
}
else
Assert(found);

57
src/backend/postmaster/postmaster.c
View File

@ -95,7 +95,7 @@
#include "access/xlog.h"
#include "bootstrap/bootstrap.h"
#include "catalog/pg_control.h"
#include "lib/dllist.h"
#include "lib/ilist.h"
#include "libpq/auth.h"
#include "libpq/ip.h"
#include "libpq/libpq.h"
@ -146,10 +146,10 @@ typedef struct bkend
int child_slot; /* PMChildSlot for this backend, if any */
bool is_autovacuum; /* is it an autovacuum process? */
bool dead_end; /* is it going to send an error and quit? */
Dlelem elem; /* list link in BackendList */
dlist_node elem; /* list link in BackendList */
} Backend;
static Dllist *BackendList;
static dlist_head BackendList = DLIST_STATIC_INIT(BackendList);
#ifdef EXEC_BACKEND
static Backend *ShmemBackendArray;
@ -1027,11 +1027,6 @@ PostmasterMain(int argc, char *argv[])
*/
set_stack_base();
/*
* Initialize the list of active backends.
*/
BackendList = DLNewList();
/*
* Initialize pipe (or process handle on Windows) that allows children to
* wake up from sleep on postmaster death.
@ -1872,7 +1867,7 @@ processCancelRequest(Port *port, void *pkt)
Backend *bp;
#ifndef EXEC_BACKEND
Dlelem *curr;
dlist_iter iter;
#else
int i;
#endif
@ -1886,9 +1881,9 @@ processCancelRequest(Port *port, void *pkt)
* duplicate array in shared memory.
*/
#ifndef EXEC_BACKEND
for (curr = DLGetHead(BackendList); curr; curr = DLGetSucc(curr))
dlist_foreach(iter, &BackendList)
{
bp = (Backend *) DLE_VAL(curr);
bp = dlist_container(Backend, elem, iter.cur);
#else
for (i = MaxLivePostmasterChildren() - 1; i >= 0; i--)
{
@ -2648,7 +2643,7 @@ static void
CleanupBackend(int pid,
int exitstatus) /* child's exit status. */
{
Dlelem *curr;
dlist_mutable_iter iter;
LogChildExit(DEBUG2, _("server process"), pid, exitstatus);
@ -2680,9 +2675,9 @@ CleanupBackend(int pid,
return;
}
for (curr = DLGetHead(BackendList); curr; curr = DLGetSucc(curr))
dlist_foreach_modify(iter, &BackendList)
{
Backend *bp = (Backend *) DLE_VAL(curr);
Backend *bp = dlist_container(Backend, elem, iter.cur);
if (bp->pid == pid)
{
@ -2701,7 +2696,7 @@ CleanupBackend(int pid,
ShmemBackendArrayRemove(bp);
#endif
}
DLRemove(curr);
dlist_delete(&BackendList, iter.cur);
free(bp);
break;
}
@ -2718,8 +2713,7 @@ CleanupBackend(int pid,
static void
HandleChildCrash(int pid, int exitstatus, const char *procname)
{
Dlelem *curr,
*next;
dlist_mutable_iter iter;
Backend *bp;
/*
@ -2734,10 +2728,10 @@ HandleChildCrash(int pid, int exitstatus, const char *procname)
}
/* Process regular backends */
for (curr = DLGetHead(BackendList); curr; curr = next)
dlist_foreach_modify(iter, &BackendList)
{
next = DLGetSucc(curr);
bp = (Backend *) DLE_VAL(curr);
bp = dlist_container(Backend, elem, iter.cur);
if (bp->pid == pid)
{
/*
@ -2750,7 +2744,7 @@ HandleChildCrash(int pid, int exitstatus, const char *procname)
ShmemBackendArrayRemove(bp);
#endif
}
DLRemove(curr);
dlist_delete(&BackendList, iter.cur);
free(bp);
/* Keep looping so we can signal remaining backends */
}
@ -3113,7 +3107,7 @@ PostmasterStateMachine(void)
* normal state transition leading up to PM_WAIT_DEAD_END, or during
* FatalError processing.
*/
if (DLGetHead(BackendList) == NULL &&
if (dlist_is_empty(&BackendList) &&
PgArchPID == 0 && PgStatPID == 0)
{
/* These other guys should be dead already */
@ -3239,12 +3233,12 @@ signal_child(pid_t pid, int signal)
static bool
SignalSomeChildren(int signal, int target)
{
Dlelem *curr;
dlist_iter iter;
bool signaled = false;
for (curr = DLGetHead(BackendList); curr; curr = DLGetSucc(curr))
dlist_foreach(iter, &BackendList)
{
Backend *bp = (Backend *) DLE_VAL(curr);
Backend *bp = dlist_container(Backend, elem, iter.cur);
if (bp->dead_end)
continue;
@ -3382,8 +3376,8 @@ BackendStartup(Port *port)
*/
bn->pid = pid;
bn->is_autovacuum = false;
DLInitElem(&bn->elem, bn);
DLAddHead(BackendList, &bn->elem);
dlist_push_head(&BackendList, &bn->elem);
#ifdef EXEC_BACKEND
if (!bn->dead_end)
ShmemBackendArrayAdd(bn);
@ -4491,12 +4485,12 @@ PostmasterRandom(void)
static int
CountChildren(int target)
{
Dlelem *curr;
dlist_iter iter;
int cnt = 0;
for (curr = DLGetHead(BackendList); curr; curr = DLGetSucc(curr))
dlist_foreach(iter, &BackendList)
{
Backend *bp = (Backend *) DLE_VAL(curr);
Backend *bp = dlist_container(Backend, elem, iter.cur);
if (bp->dead_end)
continue;
@ -4675,8 +4669,7 @@ StartAutovacuumWorker(void)
if (bn->pid > 0)
{
bn->is_autovacuum = true;
DLInitElem(&bn->elem, bn);
DLAddHead(BackendList, &bn->elem);
dlist_push_head(&BackendList, &bn->elem);
#ifdef EXEC_BACKEND
ShmemBackendArrayAdd(bn);
#endif

142
src/backend/utils/cache/catcache.c vendored
View File

@ -291,7 +291,7 @@ CatalogCacheComputeTupleHashValue(CatCache *cache, HeapTuple tuple)
static void
CatCachePrintStats(int code, Datum arg)
{
CatCache *cache;
slist_iter iter;
long cc_searches = 0;
long cc_hits = 0;
long cc_neg_hits = 0;
@ -300,8 +300,10 @@ CatCachePrintStats(int code, Datum arg)
long cc_lsearches = 0;
long cc_lhits = 0;
for (cache = CacheHdr->ch_caches; cache; cache = cache->cc_next)
slist_foreach(iter, &CacheHdr->ch_caches)
{
CatCache *cache = slist_container(CatCache, cc_next, iter.cur);
if (cache->cc_ntup == 0 && cache->cc_searches == 0)
continue; /* don't print unused caches */
elog(DEBUG2, "catcache %s/%u: %d tup, %ld srch, %ld+%ld=%ld hits, %ld+%ld=%ld loads, %ld invals, %ld lsrch, %ld lhits",
@ -368,8 +370,7 @@ CatCacheRemoveCTup(CatCache *cache, CatCTup *ct)
return; /* nothing left to do */
}
/* delink from linked list */
DLRemove(&ct->cache_elem);
dlist_delete(ct->cache_bucket, &ct->cache_elem);
/* free associated tuple data */
if (ct->tuple.t_data != NULL)
@ -412,7 +413,7 @@ CatCacheRemoveCList(CatCache *cache, CatCList *cl)
}
/* delink from linked list */
DLRemove(&cl->cache_elem);
dlist_delete(&cache->cc_lists, &cl->cache_elem);
/* free associated tuple data */
if (cl->tuple.t_data != NULL)
@ -442,18 +443,18 @@ CatCacheRemoveCList(CatCache *cache, CatCList *cl)
void
CatalogCacheIdInvalidate(int cacheId, uint32 hashValue)
{
CatCache *ccp;
slist_iter cache_iter;
CACHE1_elog(DEBUG2, "CatalogCacheIdInvalidate: called");
/*
* inspect caches to find the proper cache
*/
for (ccp = CacheHdr->ch_caches; ccp; ccp = ccp->cc_next)
slist_foreach(cache_iter, &CacheHdr->ch_caches)
{
Index hashIndex;
Dlelem *elt,
*nextelt;
dlist_mutable_iter iter;
CatCache *ccp = slist_container(CatCache, cc_next, cache_iter.cur);
if (cacheId != ccp->id)
continue;
@ -468,11 +469,9 @@ CatalogCacheIdInvalidate(int cacheId, uint32 hashValue)
* Invalidate *all* CatCLists in this cache; it's too hard to tell
* which searches might still be correct, so just zap 'em all.
*/
for (elt = DLGetHead(&ccp->cc_lists); elt; elt = nextelt)
dlist_foreach_modify(iter, &ccp->cc_lists)
{
CatCList *cl = (CatCList *) DLE_VAL(elt);
nextelt = DLGetSucc(elt);
CatCList *cl = dlist_container(CatCList, cache_elem, iter.cur);
if (cl->refcount > 0)
cl->dead = true;
@ -484,12 +483,9 @@ CatalogCacheIdInvalidate(int cacheId, uint32 hashValue)
* inspect the proper hash bucket for tuple matches
*/
hashIndex = HASH_INDEX(hashValue, ccp->cc_nbuckets);
for (elt = DLGetHead(&ccp->cc_bucket[hashIndex]); elt; elt = nextelt)
dlist_foreach_modify(iter, &ccp->cc_bucket[hashIndex])
{
CatCTup *ct = (CatCTup *) DLE_VAL(elt);
nextelt = DLGetSucc(elt);
CatCTup *ct = dlist_container(CatCTup, cache_elem, iter.cur);
if (hashValue == ct->hash_value)
{
@ -557,17 +553,18 @@ AtEOXact_CatCache(bool isCommit)
#ifdef USE_ASSERT_CHECKING
if (assert_enabled)
{
CatCache *ccp;
slist_iter cache_iter;
for (ccp = CacheHdr->ch_caches; ccp; ccp = ccp->cc_next)
slist_foreach(cache_iter, &(CacheHdr->ch_caches))
{
Dlelem *elt;
CatCache *ccp = slist_container(CatCache, cc_next, cache_iter.cur);
dlist_iter iter;
int i;
/* Check CatCLists */
for (elt = DLGetHead(&ccp->cc_lists); elt; elt = DLGetSucc(elt))
dlist_foreach(iter, &ccp->cc_lists)
{
CatCList *cl = (CatCList *) DLE_VAL(elt);
CatCList *cl = dlist_container(CatCList, cache_elem, iter.cur);
Assert(cl->cl_magic == CL_MAGIC);
Assert(cl->refcount == 0);
@ -577,11 +574,11 @@ AtEOXact_CatCache(bool isCommit)
/* Check individual tuples */
for (i = 0; i < ccp->cc_nbuckets; i++)
{
for (elt = DLGetHead(&ccp->cc_bucket[i]);
elt;
elt = DLGetSucc(elt))
dlist_head *bucket = &ccp->cc_bucket[i];
dlist_foreach(iter, bucket)
{
CatCTup *ct = (CatCTup *) DLE_VAL(elt);
CatCTup *ct = dlist_container(CatCTup, cache_elem, iter.cur);
Assert(ct->ct_magic == CT_MAGIC);
Assert(ct->refcount == 0);
@ -604,16 +601,13 @@ AtEOXact_CatCache(bool isCommit)
static void
ResetCatalogCache(CatCache *cache)
{
Dlelem *elt,
*nextelt;
dlist_mutable_iter iter;
int i;
/* Remove each list in this cache, or at least mark it dead */
for (elt = DLGetHead(&cache->cc_lists); elt; elt = nextelt)
dlist_foreach_modify(iter, &cache->cc_lists)
{
CatCList *cl = (CatCList *) DLE_VAL(elt);
nextelt = DLGetSucc(elt);
CatCList *cl = dlist_container(CatCList, cache_elem, iter.cur);
if (cl->refcount > 0)
cl->dead = true;
@ -624,11 +618,11 @@ ResetCatalogCache(CatCache *cache)
/* Remove each tuple in this cache, or at least mark it dead */
for (i = 0; i < cache->cc_nbuckets; i++)
{
for (elt = DLGetHead(&cache->cc_bucket[i]); elt; elt = nextelt)
{
CatCTup *ct = (CatCTup *) DLE_VAL(elt);
dlist_head *bucket = &cache->cc_bucket[i];
nextelt = DLGetSucc(elt);
dlist_foreach_modify(iter, bucket)
{
CatCTup *ct = dlist_container(CatCTup, cache_elem, iter.cur);
if (ct->refcount > 0 ||
(ct->c_list && ct->c_list->refcount > 0))
@ -654,12 +648,16 @@ ResetCatalogCache(CatCache *cache)
void
ResetCatalogCaches(void)
{
CatCache *cache;
slist_iter iter;
CACHE1_elog(DEBUG2, "ResetCatalogCaches called");
for (cache = CacheHdr->ch_caches; cache; cache = cache->cc_next)
slist_foreach(iter, &CacheHdr->ch_caches)
{
CatCache *cache = slist_container(CatCache, cc_next, iter.cur);
ResetCatalogCache(cache);
}
CACHE1_elog(DEBUG2, "end of ResetCatalogCaches call");
}
@ -680,12 +678,14 @@ ResetCatalogCaches(void)
void
CatalogCacheFlushCatalog(Oid catId)
{
CatCache *cache;
slist_iter iter;
CACHE2_elog(DEBUG2, "CatalogCacheFlushCatalog called for %u", catId);
for (cache = CacheHdr->ch_caches; cache; cache = cache->cc_next)
slist_foreach(iter, &(CacheHdr->ch_caches))
{
CatCache *cache = slist_container(CatCache, cc_next, iter.cur);
/* Does this cache store tuples of the target catalog? */
if (cache->cc_reloid == catId)
{
@ -760,7 +760,7 @@ InitCatCache(int id,
if (CacheHdr == NULL)
{
CacheHdr = (CatCacheHeader *) palloc(sizeof(CatCacheHeader));
CacheHdr->ch_caches = NULL;
slist_init(&CacheHdr->ch_caches);
CacheHdr->ch_ntup = 0;
#ifdef CATCACHE_STATS
/* set up to dump stats at backend exit */
@ -770,10 +770,8 @@ InitCatCache(int id,
/*
* allocate a new cache structure
*
* Note: we assume zeroing initializes the Dllist headers correctly
*/
cp = (CatCache *) palloc0(sizeof(CatCache) + nbuckets * sizeof(Dllist));
cp = (CatCache *) palloc0(sizeof(CatCache) + nbuckets * sizeof(dlist_node));
/*
* initialize the cache's relation information for the relation
@ -792,6 +790,9 @@ InitCatCache(int id,
for (i = 0; i < nkeys; ++i)
cp->cc_key[i] = key[i];
dlist_init(&cp->cc_lists);
MemSet(&cp->cc_bucket, 0, nbuckets * sizeof(dlist_head));
/*
* new cache is initialized as far as we can go for now. print some
* debugging information, if appropriate.
@ -801,8 +802,7 @@ InitCatCache(int id,
/*
* add completed cache to top of group header's list
*/
cp->cc_next = CacheHdr->ch_caches;
CacheHdr->ch_caches = cp;
slist_push_head(&CacheHdr->ch_caches, &cp->cc_next);
/*
* back to the old context before we return...
@ -1060,7 +1060,8 @@ SearchCatCache(CatCache *cache,
ScanKeyData cur_skey[CATCACHE_MAXKEYS];
uint32 hashValue;
Index hashIndex;
Dlelem *elt;
dlist_mutable_iter iter;
dlist_head *bucket;
CatCTup *ct;
Relation relation;
SysScanDesc scandesc;
@ -1094,13 +1095,13 @@ SearchCatCache(CatCache *cache,
/*
* scan the hash bucket until we find a match or exhaust our tuples
*/
for (elt = DLGetHead(&cache->cc_bucket[hashIndex]);
elt;
elt = DLGetSucc(elt))
bucket = &cache->cc_bucket[hashIndex];
dlist_foreach_modify(iter, bucket)
{
bool res;
ct = (CatCTup *) DLE_VAL(elt);
ct = dlist_container(CatCTup, cache_elem, iter.cur);
if (ct->dead)
continue; /* ignore dead entries */
@ -1125,7 +1126,7 @@ SearchCatCache(CatCache *cache,
* most frequently accessed elements in any hashbucket will tend to be
* near the front of the hashbucket's list.)
*/
DLMoveToFront(&ct->cache_elem);
dlist_move_head(bucket, &ct->cache_elem);
/*
* If it's a positive entry, bump its refcount and return it. If it's
@ -1340,7 +1341,7 @@ SearchCatCacheList(CatCache *cache,
{
ScanKeyData cur_skey[CATCACHE_MAXKEYS];
uint32 lHashValue;
Dlelem *elt;
dlist_iter iter;
CatCList *cl;
CatCTup *ct;
List *volatile ctlist;
@ -1382,13 +1383,11 @@ SearchCatCacheList(CatCache *cache,
/*
* scan the items until we find a match or exhaust our list
*/
for (elt = DLGetHead(&cache->cc_lists);
elt;
elt = DLGetSucc(elt))
dlist_foreach(iter, &cache->cc_lists)
{
bool res;
cl = (CatCList *) DLE_VAL(elt);
cl = dlist_container(CatCList, cache_elem, iter.cur);
if (cl->dead)
continue; /* ignore dead entries */
@ -1416,7 +1415,7 @@ SearchCatCacheList(CatCache *cache,
* since there's no point in that unless they are searched for
* individually.)
*/
DLMoveToFront(&cl->cache_elem);
dlist_move_head(&cache->cc_lists, &cl->cache_elem);
/* Bump the list's refcount and return it */
ResourceOwnerEnlargeCatCacheListRefs(CurrentResourceOwner);
@ -1468,6 +1467,8 @@ SearchCatCacheList(CatCache *cache,
{
uint32 hashValue;
Index hashIndex;
bool found = false;
dlist_head *bucket;
/*
* See if there's an entry for this tuple already.
@ -1476,11 +1477,10 @@ SearchCatCacheList(CatCache *cache,
hashValue = CatalogCacheComputeTupleHashValue(cache, ntp);
hashIndex = HASH_INDEX(hashValue, cache->cc_nbuckets);
for (elt = DLGetHead(&cache->cc_bucket[hashIndex]);
elt;
elt = DLGetSucc(elt))
bucket = &cache->cc_bucket[hashIndex];
dlist_foreach(iter, bucket)
{
ct = (CatCTup *) DLE_VAL(elt);
ct = dlist_container(CatCTup, cache_elem, iter.cur);
if (ct->dead || ct->negative)
continue; /* ignore dead and negative entries */
@ -1498,10 +1498,11 @@ SearchCatCacheList(CatCache *cache,
if (ct->c_list)
continue;
found = true;
break; /* A-OK */
}
if (elt == NULL)
if (!found)
{
/* We didn't find a usable entry, so make a new one */
ct = CatalogCacheCreateEntry(cache, ntp,
@ -1564,7 +1565,6 @@ SearchCatCacheList(CatCache *cache,
cl->cl_magic = CL_MAGIC;
cl->my_cache = cache;
DLInitElem(&cl->cache_elem, cl);
cl->refcount = 0; /* for the moment */
cl->dead = false;
cl->ordered = ordered;
@ -1587,7 +1587,7 @@ SearchCatCacheList(CatCache *cache,
}
Assert(i == nmembers);
DLAddHead(&cache->cc_lists, &cl->cache_elem);
dlist_push_head(&cache->cc_lists, &cl->cache_elem);
/* Finally, bump the list's refcount and return it */
cl->refcount++;
@ -1664,14 +1664,15 @@ CatalogCacheCreateEntry(CatCache *cache, HeapTuple ntp,
*/
ct->ct_magic = CT_MAGIC;
ct->my_cache = cache;
DLInitElem(&ct->cache_elem, (void *) ct);
ct->cache_bucket = &cache->cc_bucket[hashIndex];
ct->c_list = NULL;
ct->refcount = 0; /* for the moment */
ct->dead = false;
ct->negative = negative;
ct->hash_value = hashValue;
DLAddHead(&cache->cc_bucket[hashIndex], &ct->cache_elem);
dlist_push_head(ct->cache_bucket, &ct->cache_elem);
cache->cc_ntup++;
CacheHdr->ch_ntup++;
@ -1785,7 +1786,7 @@ PrepareToInvalidateCacheTuple(Relation relation,
HeapTuple newtuple,
void (*function) (int, uint32, Oid))
{
CatCache *ccp;
slist_iter iter;
Oid reloid;
CACHE1_elog(DEBUG2, "PrepareToInvalidateCacheTuple: called");
@ -1808,10 +1809,11 @@ PrepareToInvalidateCacheTuple(Relation relation,
* ----------------
*/
for (ccp = CacheHdr->ch_caches; ccp; ccp = ccp->cc_next)
slist_foreach(iter, &(CacheHdr->ch_caches))
{
uint32 hashvalue;
Oid dbid;
CatCache *ccp = slist_container(CatCache, cc_next, iter.cur);
if (ccp->cc_reloid != reloid)
continue;