diff options
Diffstat (limited to 'src/backend/port/sysv_shmem.c')
| -rw-r--r-- | src/backend/port/sysv_shmem.c | 96 |
1 files changed, 48 insertions, 48 deletions
diff --git a/src/backend/port/sysv_shmem.c b/src/backend/port/sysv_shmem.c index 23b945f0850..3092ca2a377 100644 --- a/src/backend/port/sysv_shmem.c +++ b/src/backend/port/sysv_shmem.c @@ -10,7 +10,7 @@ * Portions Copyright (c) 1994, Regents of the University of California * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/port/sysv_shmem.c,v 1.43 2005/08/20 23:26:13 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/port/sysv_shmem.c,v 1.44 2005/10/15 02:49:22 momjian Exp $ * *------------------------------------------------------------------------- */ @@ -81,11 +81,10 @@ InternalIpcMemoryCreate(IpcMemoryKey memKey, Size size) if (shmid < 0) { /* - * Fail quietly if error indicates a collision with existing - * segment. One would expect EEXIST, given that we said IPC_EXCL, - * but perhaps we could get a permission violation instead? Also, - * EIDRM might occur if an old seg is slated for destruction but - * not gone yet. + * Fail quietly if error indicates a collision with existing segment. + * One would expect EEXIST, given that we said IPC_EXCL, but perhaps + * we could get a permission violation instead? Also, EIDRM might + * occur if an old seg is slated for destruction but not gone yet. */ if (errno == EEXIST || errno == EACCES #ifdef EIDRM @@ -99,41 +98,41 @@ InternalIpcMemoryCreate(IpcMemoryKey memKey, Size size) */ ereport(FATAL, (errmsg("could not create shared memory segment: %m"), - errdetail("Failed system call was shmget(key=%lu, size=%lu, 0%o).", - (unsigned long) memKey, (unsigned long) size, - IPC_CREAT | IPC_EXCL | IPCProtection), + errdetail("Failed system call was shmget(key=%lu, size=%lu, 0%o).", + (unsigned long) memKey, (unsigned long) size, + IPC_CREAT | IPC_EXCL | IPCProtection), (errno == EINVAL) ? errhint("This error usually means that PostgreSQL's request for a shared memory " - "segment exceeded your kernel's SHMMAX parameter. You can either " + "segment exceeded your kernel's SHMMAX parameter. You can either " "reduce the request size or reconfigure the kernel with larger SHMMAX. " - "To reduce the request size (currently %lu bytes), reduce " - "PostgreSQL's shared_buffers parameter (currently %d) and/or " + "To reduce the request size (currently %lu bytes), reduce " + "PostgreSQL's shared_buffers parameter (currently %d) and/or " "its max_connections parameter (currently %d).\n" "If the request size is already small, it's possible that it is less than " "your kernel's SHMMIN parameter, in which case raising the request size or " "reconfiguring SHMMIN is called for.\n" - "The PostgreSQL documentation contains more information about shared " + "The PostgreSQL documentation contains more information about shared " "memory configuration.", (unsigned long) size, NBuffers, MaxBackends) : 0, (errno == ENOMEM) ? errhint("This error usually means that PostgreSQL's request for a shared " - "memory segment exceeded available memory or swap space. " - "To reduce the request size (currently %lu bytes), reduce " - "PostgreSQL's shared_buffers parameter (currently %d) and/or " + "memory segment exceeded available memory or swap space. " + "To reduce the request size (currently %lu bytes), reduce " + "PostgreSQL's shared_buffers parameter (currently %d) and/or " "its max_connections parameter (currently %d).\n" - "The PostgreSQL documentation contains more information about shared " + "The PostgreSQL documentation contains more information about shared " "memory configuration.", (unsigned long) size, NBuffers, MaxBackends) : 0, (errno == ENOSPC) ? errhint("This error does *not* mean that you have run out of disk space. " "It occurs either if all available shared memory IDs have been taken, " "in which case you need to raise the SHMMNI parameter in your kernel, " - "or because the system's overall limit for shared memory has been " - "reached. If you cannot increase the shared memory limit, " - "reduce PostgreSQL's shared memory request (currently %lu bytes), " - "by reducing its shared_buffers parameter (currently %d) and/or " + "or because the system's overall limit for shared memory has been " + "reached. If you cannot increase the shared memory limit, " + "reduce PostgreSQL's shared memory request (currently %lu bytes), " + "by reducing its shared_buffers parameter (currently %d) and/or " "its max_connections parameter (currently %d).\n" - "The PostgreSQL documentation contains more information about shared " + "The PostgreSQL documentation contains more information about shared " "memory configuration.", (unsigned long) size, NBuffers, MaxBackends) : 0)); } @@ -187,7 +186,7 @@ IpcMemoryDelete(int status, Datum shmId) * Is a previously-existing shmem segment still existing and in use? * * The point of this exercise is to detect the case where a prior postmaster - * crashed, but it left child backends that are still running. Therefore + * crashed, but it left child backends that are still running. Therefore * we only care about shmem segments that are associated with the intended * DataDir. This is an important consideration since accidental matches of * shmem segment IDs are reasonably common. @@ -197,35 +196,38 @@ PGSharedMemoryIsInUse(unsigned long id1, unsigned long id2) { IpcMemoryId shmId = (IpcMemoryId) id2; struct shmid_ds shmStat; + #ifndef WIN32 struct stat statbuf; PGShmemHeader *hdr; #endif /* - * We detect whether a shared memory segment is in use by seeing - * whether it (a) exists and (b) has any processes are attached to it. + * We detect whether a shared memory segment is in use by seeing whether + * it (a) exists and (b) has any processes are attached to it. */ if (shmctl(shmId, IPC_STAT, &shmStat) < 0) { /* * EINVAL actually has multiple possible causes documented in the - * shmctl man page, but we assume it must mean the segment no - * longer exists. + * shmctl man page, but we assume it must mean the segment no longer + * exists. */ if (errno == EINVAL) return false; + /* - * EACCES implies that the segment belongs to some other userid, - * which means it is not a Postgres shmem segment (or at least, - * not one that is relevant to our data directory). + * EACCES implies that the segment belongs to some other userid, which + * means it is not a Postgres shmem segment (or at least, not one that + * is relevant to our data directory). */ if (errno == EACCES) return false; + /* - * Otherwise, we had better assume that the segment is in use. - * The only likely case is EIDRM, which implies that the segment - * has been IPC_RMID'd but there are still processes attached to it. + * Otherwise, we had better assume that the segment is in use. The + * only likely case is EIDRM, which implies that the segment has been + * IPC_RMID'd but there are still processes attached to it. */ return true; } @@ -295,6 +297,7 @@ PGSharedMemoryCreate(Size size, bool makePrivate, int port) void *memAddress; PGShmemHeader *hdr; IpcMemoryId shmid; + #ifndef WIN32 struct stat statbuf; #endif @@ -338,11 +341,10 @@ PGSharedMemoryCreate(Size size, bool makePrivate, int port) } /* - * The segment appears to be from a dead Postgres process, or from - * a previous cycle of life in this same process. Zap it, if - * possible. This probably shouldn't fail, but if it does, assume - * the segment belongs to someone else after all, and continue - * quietly. + * The segment appears to be from a dead Postgres process, or from a + * previous cycle of life in this same process. Zap it, if possible. + * This probably shouldn't fail, but if it does, assume the segment + * belongs to someone else after all, and continue quietly. */ shmdt(memAddress); if (shmctl(shmid, IPC_RMID, NULL) < 0) @@ -356,17 +358,16 @@ PGSharedMemoryCreate(Size size, bool makePrivate, int port) break; /* successful create and attach */ /* - * Can only get here if some other process managed to create the - * same shmem key before we did. Let him have that one, loop - * around to try next key. + * Can only get here if some other process managed to create the same + * shmem key before we did. Let him have that one, loop around to try + * next key. */ } /* - * OK, we created a new segment. Mark it as created by this process. - * The order of assignments here is critical so that another Postgres - * process can't see the header as valid but belonging to an invalid - * PID! + * OK, we created a new segment. Mark it as created by this process. The + * order of assignments here is critical so that another Postgres process + * can't see the header as valid but belonging to an invalid PID! */ hdr = (PGShmemHeader *) memAddress; hdr->creatorPID = getpid(); @@ -401,7 +402,7 @@ PGSharedMemoryCreate(Size size, bool makePrivate, int port) /* * PGSharedMemoryReAttach * - * Re-attach to an already existing shared memory segment. In the non + * Re-attach to an already existing shared memory segment. In the non * EXEC_BACKEND case this is not used, because postmaster children inherit * the shared memory segment attachment via fork(). * @@ -436,8 +437,7 @@ PGSharedMemoryReAttach(void) UsedShmemSegAddr = hdr; /* probably redundant */ } - -#endif /* EXEC_BACKEND */ +#endif /* EXEC_BACKEND */ /* * PGSharedMemoryDetach |