diff options
| author |   Jens Axboe <jens.axboe@oracle.com> | 2009-04-06 14:48:07 +0200 |
|---|---|---|
| committer |   Linus Torvalds <torvalds@linux-foundation.org> | 2009-04-06 08:04:54 -0700 |
| commit | aeb6fafb8fa53266d70ca7474fcda2bdaf96524a (patch) | |
| tree | ebe8e0c616a9dbfdfe5184b64d0150ea02d3d1b2 /include/linux/fs.h | |
| parent | block: enabling plugging on SSD devices that don't do queuing (diff) | |
| download | linux-dev-aeb6fafb8fa53266d70ca7474fcda2bdaf96524a.tar.xz linux-dev-aeb6fafb8fa53266d70ca7474fcda2bdaf96524a.zip | |
block: Add flag for telling the IO schedulers NOT to anticipate more IO
By default, CFQ will anticipate more IO from a given io context if the
previously completed IO was sync. This used to be fine, since the only
sync IO was reads and O_DIRECT writes. But with more "normal" sync writes
being used now, we don't want to anticipate for those.
Add a bio/request flag that informs the IO scheduler that this is a sync
request that we should not idle for. Introduce WRITE_ODIRECT specifically
for O_DIRECT writes, and make sure that the other sync writes set this
flag.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to '')
| -rw-r--r-- | include/linux/fs.h | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/include/linux/fs.h b/include/linux/fs.h index ea0510978f76..cae5720f431c 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -95,11 +95,12 @@ struct inodes_stat_t { #define SWRITE 3 /* for ll_rw_block() - wait for buffer lock */ #define READ_SYNC (READ | (1 << BIO_RW_SYNCIO) | (1 << BIO_RW_UNPLUG)) #define READ_META (READ | (1 << BIO_RW_META)) -#define WRITE_SYNC (WRITE | (1 << BIO_RW_SYNCIO) | (1 << BIO_RW_UNPLUG)) -#define WRITE_SYNC_PLUG (WRITE | (1 << BIO_RW_SYNCIO)) -#define SWRITE_SYNC (SWRITE | (1 << BIO_RW_SYNCIO) | (1 << BIO_RW_UNPLUG)) +#define WRITE_SYNC_PLUG (WRITE | (1 << BIO_RW_SYNCIO) | (1 << BIO_RW_NOIDLE)) +#define WRITE_SYNC (WRITE_SYNC_PLUG | (1 << BIO_RW_UNPLUG)) +#define WRITE_ODIRECT (WRITE | (1 << BIO_RW_SYNCIO) | (1 << BIO_RW_UNPLUG)) #define SWRITE_SYNC_PLUG \ - (SWRITE | (1 << BIO_RW_SYNCIO)) + (SWRITE | (1 << BIO_RW_SYNCIO) | (1 << BIO_RW_NOIDLE)) +#define SWRITE_SYNC (SWRITE_SYNC_PLUG | (1 << BIO_RW_UNPLUG)) #define WRITE_BARRIER (WRITE | (1 << BIO_RW_BARRIER)) #define DISCARD_NOBARRIER (1 << BIO_RW_DISCARD) #define DISCARD_BARRIER ((1 << BIO_RW_DISCARD) | (1 << BIO_RW_BARRIER)) |