From 195f1642285d59b4bd42ec2ba8bbcf46b8aedd93 Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Thu, 29 Dec 2005 18:08:05 +0000 Subject: Get rid of the SpinLockAcquire/SpinLockAcquire_NoHoldoff distinction in favor of having just one set of macros that don't do HOLD/RESUME_INTERRUPTS (hence, these correspond to the old SpinLockAcquire_NoHoldoff case). Given our coding rules for spinlock use, there is no reason to allow CHECK_FOR_INTERRUPTS to be done while holding a spinlock, and also there is no situation where ImmediateInterruptOK will be true while holding a spinlock. Therefore doing HOLD/RESUME_INTERRUPTS while taking/releasing a spinlock is just a waste of cycles. Qingqing Zhou and Tom Lane. --- src/include/storage/buf_internals.h | 20 ++++++-------------- 1 file changed, 6 insertions(+), 14 deletions(-) (limited to 'src/include/storage/buf_internals.h') diff --git a/src/include/storage/buf_internals.h b/src/include/storage/buf_internals.h index 3bab9e85b40..71fa0b08d48 100644 --- a/src/include/storage/buf_internals.h +++ b/src/include/storage/buf_internals.h @@ -8,7 +8,7 @@ * Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group * Portions Copyright (c) 1994, Regents of the University of California * - * $PostgreSQL: pgsql/src/include/storage/buf_internals.h,v 1.83 2005/11/22 18:17:31 momjian Exp $ + * $PostgreSQL: pgsql/src/include/storage/buf_internals.h,v 1.84 2005/12/29 18:08:05 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -138,24 +138,16 @@ typedef struct sbufdesc #define FREENEXT_NOT_IN_LIST (-2) /* - * Macros for acquiring/releasing a buffer header's spinlock. The - * NoHoldoff cases may be used when we know that we hold some LWLock - * and therefore interrupts are already held off. Do not apply these - * to local buffers! + * Macros for acquiring/releasing a shared buffer header's spinlock. + * Do not apply these to local buffers! * * Note: as a general coding rule, if you are using these then you probably - * want to be using a volatile-qualified pointer to the buffer header, to + * need to be using a volatile-qualified pointer to the buffer header, to * ensure that the compiler doesn't rearrange accesses to the header to * occur before or after the spinlock is acquired/released. */ -#define LockBufHdr(bufHdr) \ - SpinLockAcquire(&(bufHdr)->buf_hdr_lock) -#define UnlockBufHdr(bufHdr) \ - SpinLockRelease(&(bufHdr)->buf_hdr_lock) -#define LockBufHdr_NoHoldoff(bufHdr) \ - SpinLockAcquire_NoHoldoff(&(bufHdr)->buf_hdr_lock) -#define UnlockBufHdr_NoHoldoff(bufHdr) \ - SpinLockRelease_NoHoldoff(&(bufHdr)->buf_hdr_lock) +#define LockBufHdr(bufHdr) SpinLockAcquire(&(bufHdr)->buf_hdr_lock) +#define UnlockBufHdr(bufHdr) SpinLockRelease(&(bufHdr)->buf_hdr_lock) /* in buf_init.c */ -- cgit v1.2.3