From 8f563edefdc2f276b3d8abeb019af1ff172bf7d9 Mon Sep 17 00:00:00 2001 From: Thomas Munro Date: Sat, 27 Feb 2021 13:34:37 +1300 Subject: [PATCH v8 1/2] Introduce symbolic names for FeBeWaitSet positions. Previously we used 0 and 1 to refer to the socket and latch in far flung parts of the tree, without any explanation. Also use PGINVALID_SOCKET rather than -1 in the place where we weren't already. Reviewed-by: Kyotaro Horiguchi Discussion: https://postgr.es/m/CA%2BhUKGJAC4Oqao%3DqforhNey20J8CiG2R%3DoBPqvfR0vOJrFysGw%40mail.gmail.com --- src/backend/libpq/be-secure.c | 4 ++-- src/backend/libpq/pqcomm.c | 18 +++++++++++++++--- src/backend/utils/init/miscinit.c | 6 ++++-- src/include/libpq/libpq.h | 3 +++ 4 files changed, 24 insertions(+), 7 deletions(-) diff --git a/src/backend/libpq/be-secure.c b/src/backend/libpq/be-secure.c index d1545a2ad6..bb603ad209 100644 --- a/src/backend/libpq/be-secure.c +++ b/src/backend/libpq/be-secure.c @@ -180,7 +180,7 @@ retry: Assert(waitfor); - ModifyWaitEvent(FeBeWaitSet, 0, waitfor, NULL); + ModifyWaitEvent(FeBeWaitSet, FeBeWaitSetSocketPos, waitfor, NULL); WaitEventSetWait(FeBeWaitSet, -1 /* no timeout */ , &event, 1, WAIT_EVENT_CLIENT_READ); @@ -292,7 +292,7 @@ retry: Assert(waitfor); - ModifyWaitEvent(FeBeWaitSet, 0, waitfor, NULL); + ModifyWaitEvent(FeBeWaitSet, FeBeWaitSetSocketPos, waitfor, NULL); WaitEventSetWait(FeBeWaitSet, -1 /* no timeout */ , &event, 1, WAIT_EVENT_CLIENT_WRITE); diff --git a/src/backend/libpq/pqcomm.c b/src/backend/libpq/pqcomm.c index 1e6b6db540..27a298f110 100644 --- a/src/backend/libpq/pqcomm.c +++ b/src/backend/libpq/pqcomm.c @@ -191,6 +191,9 @@ WaitEventSet *FeBeWaitSet; void pq_init(void) { + int socket_pos PG_USED_FOR_ASSERTS_ONLY; + int latch_pos PG_USED_FOR_ASSERTS_ONLY; + /* initialize state variables */ PqSendBufferSize = PQ_SEND_BUFFER_SIZE; PqSendBuffer = MemoryContextAlloc(TopMemoryContext, PqSendBufferSize); @@ -219,10 +222,19 @@ pq_init(void) #endif FeBeWaitSet = CreateWaitEventSet(TopMemoryContext, 3); - AddWaitEventToSet(FeBeWaitSet, WL_SOCKET_WRITEABLE, MyProcPort->sock, + socket_pos = AddWaitEventToSet(FeBeWaitSet, WL_SOCKET_WRITEABLE, + MyProcPort->sock, NULL, NULL); + latch_pos = AddWaitEventToSet(FeBeWaitSet, WL_LATCH_SET, PGINVALID_SOCKET, + MyLatch, NULL); + AddWaitEventToSet(FeBeWaitSet, WL_POSTMASTER_DEATH, PGINVALID_SOCKET, NULL, NULL); - AddWaitEventToSet(FeBeWaitSet, WL_LATCH_SET, -1, MyLatch, NULL); - AddWaitEventToSet(FeBeWaitSet, WL_POSTMASTER_DEATH, -1, NULL, NULL); + + /* + * The event positions match the order we added them, but let's sanity + * check them to be sure. + */ + Assert(socket_pos == FeBeWaitSetSocketPos); + Assert(latch_pos == FeBeWaitSetLatchPos); } /* -------------------------------- diff --git a/src/backend/utils/init/miscinit.c b/src/backend/utils/init/miscinit.c index 734c66d4e8..8de70eb46d 100644 --- a/src/backend/utils/init/miscinit.c +++ b/src/backend/utils/init/miscinit.c @@ -202,7 +202,8 @@ SwitchToSharedLatch(void) MyLatch = &MyProc->procLatch; if (FeBeWaitSet) - ModifyWaitEvent(FeBeWaitSet, 1, WL_LATCH_SET, MyLatch); + ModifyWaitEvent(FeBeWaitSet, FeBeWaitSetLatchPos, WL_LATCH_SET, + MyLatch); /* * Set the shared latch as the local one might have been set. This @@ -221,7 +222,8 @@ SwitchBackToLocalLatch(void) MyLatch = &LocalLatchData; if (FeBeWaitSet) - ModifyWaitEvent(FeBeWaitSet, 1, WL_LATCH_SET, MyLatch); + ModifyWaitEvent(FeBeWaitSet, FeBeWaitSetLatchPos, WL_LATCH_SET, + MyLatch); SetLatch(MyLatch); } diff --git a/src/include/libpq/libpq.h b/src/include/libpq/libpq.h index b41b10620a..e4e5c21565 100644 --- a/src/include/libpq/libpq.h +++ b/src/include/libpq/libpq.h @@ -55,6 +55,9 @@ extern const PGDLLIMPORT PQcommMethods *PqCommMethods; */ extern WaitEventSet *FeBeWaitSet; +#define FeBeWaitSetSocketPos 0 +#define FeBeWaitSetLatchPos 1 + extern int StreamServerPort(int family, const char *hostName, unsigned short portNumber, const char *unixSocketDir, pgsocket ListenSocket[], int MaxListen); -- 2.30.0