diff options
| -rw-r--r-- | src/backend/storage/ipc/dsm_impl.c | 35 |
1 files changed, 22 insertions, 13 deletions
diff --git a/src/backend/storage/ipc/dsm_impl.c b/src/backend/storage/ipc/dsm_impl.c index 21e2a10669e..10c392c3f03 100644 --- a/src/backend/storage/ipc/dsm_impl.c +++ b/src/backend/storage/ipc/dsm_impl.c @@ -62,6 +62,7 @@ #endif #include "common/file_perm.h" +#include "libpq/pqsignal.h" /* for PG_SETMASK macro */ #include "miscadmin.h" #include "pgstat.h" #include "portability/mem.h" @@ -306,14 +307,6 @@ dsm_impl_posix(dsm_op op, dsm_handle handle, Size request_size, shm_unlink(name); errno = save_errno; - /* - * If we received a query cancel or termination signal, we will have - * EINTR set here. If the caller said that errors are OK here, check - * for interrupts immediately. - */ - if (errno == EINTR && elevel >= ERROR) - CHECK_FOR_INTERRUPTS(); - ereport(elevel, (errcode_for_dynamic_shared_memory(), errmsg("could not resize shared memory segment \"%s\" to %zu bytes: %m", @@ -361,9 +354,21 @@ static int dsm_impl_posix_resize(int fd, off_t size) { int rc; + int save_errno; + + /* + * Block all blockable signals, except SIGQUIT. posix_fallocate() can run + * for quite a long time, and is an all-or-nothing operation. If we + * allowed SIGUSR1 to interrupt us repeatedly (for example, due to recovery + * conflicts), the retry loop might never succeed. + */ + PG_SETMASK(&BlockSig); /* Truncate (or extend) the file to the requested size. */ - rc = ftruncate(fd, size); + do + { + rc = ftruncate(fd, size); + } while (rc < 0 && errno == EINTR); /* * On Linux, a shm_open fd is backed by a tmpfs file. After resizing with @@ -377,15 +382,15 @@ dsm_impl_posix_resize(int fd, off_t size) if (rc == 0) { /* - * We may get interrupted. If so, just retry unless there is an - * interrupt pending. This avoids the possibility of looping forever - * if another backend is repeatedly trying to interrupt us. + * We still use a traditional EINTR retry loop to handle SIGCONT. + * posix_fallocate() doesn't restart automatically, and we don't want + * this to fail if you attach a debugger. */ pgstat_report_wait_start(WAIT_EVENT_DSM_FILL_ZERO_WRITE); do { rc = posix_fallocate(fd, 0, size); - } while (rc == EINTR && !(ProcDiePending || QueryCancelPending)); + } while (rc == EINTR); pgstat_report_wait_end(); /* @@ -397,6 +402,10 @@ dsm_impl_posix_resize(int fd, off_t size) } #endif /* HAVE_POSIX_FALLOCATE && __linux__ */ + save_errno = errno; + PG_SETMASK(&UnBlockSig); + errno = save_errno; + return rc; } |