forge/linux-pinenote
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Allow elevators to sort/merge discard requests

Browse source 
But blkdev_issue_discard() still emits requests which are interpreted as
soft barriers, because naïve callers might otherwise issue subsequent
writes to those same sectors, which might cross on the queue (if they're
reallocated quickly enough).

Callers still _can_ issue non-barrier discard requests, but they have to
take care of queue ordering for themselves.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
This commit is contained in:
David Woodhouse 2008-08-09 16:42:20 +01:00 • committed by Jens Axboe
commit e17fc0a1cc
8 changed files with 42 additions and 23 deletions
Download patch file Download diff file Expand all files Collapse all files

3
include/linux/fs.h
View file

@ -87,7 +87,8 @@ extern int dir_notify_enable;
#define WRITE_SYNC (WRITE | (1 << BIO_RW_SYNC))
#define SWRITE_SYNC (SWRITE | (1 << BIO_RW_SYNC))
#define WRITE_BARRIER (WRITE | (1 << BIO_RW_BARRIER))
#define WRITE_DISCARD (WRITE | (1 << BIO_RW_DISCARD))
#define DISCARD_NOBARRIER (1 << BIO_RW_DISCARD)
#define DISCARD_BARRIER ((1 << BIO_RW_DISCARD) | (1 << BIO_RW_BARRIER))
#define SEL_IN 1
#define SEL_OUT 2