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| author | Takahiro Yasui <tyasui@redhat.com> | 2009-01-06 03:04:59 +0000 |
|---|---|---|
| committer | Alasdair G Kergon <agk@redhat.com> | 2009-01-06 03:04:59 +0000 |
| commit | 6f3af01cb0eda0ec50fe1e4cbdf028269dc396fe (patch) | |
| tree | 29988ebe5a40ee1092bdbeac45eb0bdc312ff670 /drivers/md/dm-log.c | |
| parent | 10d3bd09a3c25df114f74f7f86e1b58d070bef32 (diff) | |
| download | lwn-6f3af01cb0eda0ec50fe1e4cbdf028269dc396fe.tar.gz lwn-6f3af01cb0eda0ec50fe1e4cbdf028269dc396fe.zip | |
dm log: avoid reinitialising io_req on every operation
rw_header function updates three members of io_req data every time
when I/O is processed. bi_rw and notify.fn are never modified once
they get initialized, and so they can be set in advance.
header_to_disk() can also be pulled out of write_header() since only one
caller needs it and write_header() can be replaced by rw_header()
directly.
Signed-off-by: Takahiro Yasui <tyasui@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Diffstat (limited to 'drivers/md/dm-log.c')
| -rw-r--r-- | drivers/md/dm-log.c | 17 |
1 files changed, 7 insertions, 10 deletions
diff --git a/drivers/md/dm-log.c b/drivers/md/dm-log.c index 13e2a1a1a941..691cb9c22b56 100644 --- a/drivers/md/dm-log.c +++ b/drivers/md/dm-log.c @@ -326,8 +326,6 @@ static void header_from_disk(struct log_header *core, struct log_header *disk) static int rw_header(struct log_c *lc, int rw) { lc->io_req.bi_rw = rw; - lc->io_req.mem.ptr.vma = lc->disk_header; - lc->io_req.notify.fn = NULL; return dm_io(&lc->io_req, 1, &lc->header_location, NULL); } @@ -362,12 +360,6 @@ static int read_header(struct log_c *log) return 0; } -static inline int write_header(struct log_c *log) -{ - header_to_disk(&log->header, log->disk_header); - return rw_header(log, WRITE); -} - /*---------------------------------------------------------------- * core log constructor/destructor * @@ -454,7 +446,9 @@ static int create_log_context(struct dm_dirty_log *log, struct dm_target *ti, buf_size = dm_round_up((LOG_OFFSET << SECTOR_SHIFT) + bitset_size, ti->limits.hardsect_size); lc->header_location.count = buf_size >> SECTOR_SHIFT; + lc->io_req.mem.type = DM_IO_VMA; + lc->io_req.notify.fn = NULL; lc->io_req.client = dm_io_client_create(dm_div_up(buf_size, PAGE_SIZE)); if (IS_ERR(lc->io_req.client)) { @@ -472,6 +466,7 @@ static int create_log_context(struct dm_dirty_log *log, struct dm_target *ti, return -ENOMEM; } + lc->io_req.mem.ptr.vma = lc->disk_header; lc->clean_bits = (void *)lc->disk_header + (LOG_OFFSET << SECTOR_SHIFT); } @@ -636,8 +631,10 @@ static int disk_resume(struct dm_dirty_log *log) /* set the correct number of regions in the header */ lc->header.nr_regions = lc->region_count; + header_to_disk(&lc->header, lc->disk_header); + /* write the new header */ - r = write_header(lc); + r = rw_header(lc, WRITE); if (r) { DMWARN("%s: Failed to write header on dirty region log device", lc->log_dev->name); @@ -687,7 +684,7 @@ static int disk_flush(struct dm_dirty_log *log) if (!lc->touched) return 0; - r = write_header(lc); + r = rw_header(lc, WRITE); if (r) fail_log_device(lc); else |