8000 Specify context memory for custom signals · postgrespro/pg_query_state@275de5f · GitHub
[go: up one dir, main page]
Skip to content

Commit 275de5f

Browse files
author
Maksim Milyutin
committed
Specify context memory for custom signals
1 parent 73b7295 commit 275de5f

File tree

2 files changed

+47
-20
lines changed

2 files changed

+47
-20
lines changed

‎custom_signals.patch

Lines changed: 46 additions & 5 deletions
Original file line numberDiff line numberDiff line change
@@ -1,8 +1,16 @@
11
diff --git a/src/backend/storage/ipc/procsignal.c b/src/backend/storage/ipc/procsignal.c
2-
index a3d6ac5..07270a9 100644
2+
index a3d6ac5..60732a6 100644
33
--- a/src/backend/storage/ipc/procsignal.c
44
+++ b/src/backend/storage/ipc/procsignal.c
5-
@@ -59,12 +59,17 @@ typedef struct
5+
@@ -26,6 +26,7 @@
6+
#include "storage/shmem.h"
7+
#include "storage/sinval.h"
8+
#include "tcop/tcopprot.h"
9+
+#include "utils/memutils.h"
10+
11+
12+
/*
13+
@@ -59,12 +60,17 @@ typedef struct
614
*/
715
#define NumProcSignalSlots (MaxBackends + NUM_AUXPROCTYPES)
816

@@ -20,7 +28,7 @@ index a3d6ac5..07270a9 100644
2028
/*
2129
* ProcSignalShmemSize
2230
* Compute space needed for procsignal's shared memory
23-
@@ -165,6 +170,57 @@ CleanupProcSignalState(int status, Datum arg)
31+
@@ -165,6 +171,57 @@ CleanupProcSignalState(int status, Datum arg)
2432
}
2533

2634
/*
@@ -78,7 +86,7 @@ index a3d6ac5..07270a9 100644
7886
* SendProcSignal
7987
* Send a signal to a Postgres process
8088
*
81-
@@ -259,7 +315,8 @@ CheckProcSignal(ProcSignalReason reason)
89+
@@ -259,7 +316,8 @@ CheckProcSignal(ProcSignalReason reason)
8290
void
8391
procsignal_sigusr1_handler(SIGNAL_ARGS)
8492
{
@@ -88,7 +96,7 @@ index a3d6ac5..07270a9 100644
8896

8997
if (CheckProcSignal(PROCSIG_CATCHUP_INTERRUPT))
9098
HandleCatchupInterrupt();
91-
@@ -288,9 +345,55 @@ procsignal_sigusr1_handler(SIGNAL_ARGS)
99+
@@ -288,9 +346,88 @@ procsignal_sigusr1_handler(SIGNAL_ARGS)
92100
if (CheckProcSignal(PROCSIG_RECOVERY_CONFLICT_BUFFERPIN))
93101
RecoveryConflictInterrupt(PROCSIG_RECOVERY_CONFLICT_BUFFERPIN);
94102

@@ -132,6 +140,32 @@ index a3d6ac5..07270a9 100644
132140
+CheckAndHandleCustomSignals(void)
133141
+{
134142
+ int i;
143+
+ MemoryContext oldcontext;
144+
+
145+
+ static MemoryContext hcs_context = NULL;
146+
+
147+
+ /*
148+
+ * This is invoked from ProcessInterrupts(), and since some of the
149+
+ * functions it calls contain CHECK_FOR_INTERRUPTS(), there is a potential
150+
+ * for recursive calls if more signals are received while this runs. It's
151+
+ * unclear that recursive entry would be safe, and it doesn't seem useful
152+
+ * even if it is safe, so let's block interrupts until done.
153+
+ */
154+
+ HOLD_INTERRUPTS();
155+
+
156+
+ /*
157+
+ * Moreover, CurrentMemoryContext might be pointing almost anywhere. We
158+
+ * don't want to risk leaking data into long-lived contexts, so let's do
159+
+ * our work here in a private context that we can reset on each use.
160+
+ */
161+
+ if (hcs_context == NULL) /* first time through? */
162+
+ hcs_context = AllocSetContextCreate(TopMemoryContext,
163+
+ "HandleCustomSignals",
164+
+ ALLOCSET_DEFAULT_SIZES);
165+
+ else
166+
+ MemoryContextReset(hcs_context);
167+
+
168+
+ oldcontext = MemoryContextSwitchTo(hcs_context);
135169
+
136170
+ for (i = 0; i < NUM_CUSTOM_PROCSIGNALS; i++)
137171
+ if (CustomSignalPendings[i])
@@ -143,6 +177,13 @@ index a3d6ac5..07270a9 100644
143177
+ if (handler)
144178
+ handler();
145179
+ }
180+
+
181+
+ MemoryContextSwitchTo(oldcontext);
182+
+
183+
+ /* Might as well clear the context on our way out */
184+
+ MemoryContextReset(hcs_context);
185+
+
186+
+ RESUME_INTERRUPTS();
146187
+}
147188
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
148189
index 98ccbbb..c5d649c 100644

‎signal_handler.c

Lines changed: 1 addition & 15 deletions
Original file line numberDiff line numberDiff line change
@@ -153,18 +153,7 @@ serialize_stack(char *dest, List *qs_stack)
153153
void
154154
SendQueryState(void)
155155
{
156-
shm_mq_handle *mqh;
157-
MemoryContext curCxt;
158-
MemoryContext oldCxt;
159-
160-
curCxt = AllocSetContextCreate(CurrentMemoryContext,
161-
"pg_query_state signal handler context",
162-
ALLOCSET_DEFAULT_MINSIZE,
163-
ALLOCSET_DEFAULT_INITSIZE,
164-
ALLOCSET_DEFAULT_MAXSIZE);
165-
oldCxt = MemoryContextSwitchTo(curCxt);
166-
167-
mqh = shm_mq_attach(mq, NULL, NULL);
156+
shm_mq_handle *mqh = shm_mq_attach(mq, NULL, NULL);
168157

169158
/* check if module is enabled */
170159
if (!pg_qs_enable)
@@ -210,7 +199,4 @@ SendQueryState(void)
210199
serialize_stack(msg->stack, qs_stack);
211200
shm_mq_send(mqh, msglen, msg, false);
212201
}
213-
214-
MemoryContextSwitchTo(oldCxt);
215-
MemoryContextDelete(curCxt);
216202
}

0 commit comments

Comments
 (0)
0