diff options
author | Jun'ichi Nomura <j-nomura@ce.jp.nec.com> | 2009-12-11 00:52:25 +0100 |
---|---|---|
committer | Alasdair G Kergon <agk@redhat.com> | 2009-12-11 00:52:25 +0100 |
commit | 6db4ccd6357f28c9ef7058b3bc48904c4b2ac419 (patch) | |
tree | affd099b88123c0717ec4bbfbb2503c3d7cc91f8 /firmware/cis/tamarack.cis.ihex | |
parent | dm snapshot: allow live exception store handover between tables (diff) | |
download | linux-6db4ccd6357f28c9ef7058b3bc48904c4b2ac419.tar.xz linux-6db4ccd6357f28c9ef7058b3bc48904c4b2ac419.zip |
dm: trace request based remapping
This patch adds a remapping trace to request-based dm.
BIO-based dm already has the equivalent tracepoint.
For example, under this dm stack (linear LV on multipath):
# dmsetup ls --tree -o ascii
vg-lv0 (253:1)
`-mpath0 (253:0)
|- (8:160)
|- (66:80)
|- (65:176)
`- (65:160)
Trace of 'dd of=/dev/vg/lv0 bs=128k count=1 oflag=direct' looks like this:
without the patch:
dd-6674 [000] 539.727384: block_bio_queue: 253,1 WS 0 + 256 [dd]
dd-6674 [000] 539.727392: block_remap: 253,0 WS 384 + 256 <- (253,1) 0
dd-6674 [000] 539.727394: block_bio_queue: 253,0 WS 384 + 256 [dd]
dd-6674 [000] 539.727405: block_getrq: 253,0 WS 384 + 256 [dd]
dd-6674 [000] 539.727409: block_plug: [dd]
dd-6674 [000] 539.727410: block_rq_insert: 253,0 W 0 () 384 + 256 [dd]
dd-6674 [000] 539.727416: block_rq_issue: 253,0 W 0 () 384 + 256 [dd]
dd-6674 [000] 539.727426: block_rq_insert: 65,176 W 0 () 384 + 256 [dd]
dd-6674 [000] 539.727427: block_rq_issue: 65,176 W 0 () 384 + 256 [dd]
...
and with the patch: (the line with '**' is the trace added by this patch)
dd-6617 [002] 162.914301: block_bio_queue: 253,1 WS 0 + 256 [dd]
dd-6617 [002] 162.914314: block_remap: 253,0 WS 384 + 256 <- (253,1) 0
dd-6617 [002] 162.914316: block_bio_queue: 253,0 WS 384 + 256 [dd]
dd-6617 [002] 162.914331: block_getrq: 253,0 WS 384 + 256 [dd]
dd-6617 [002] 162.914335: block_plug: [dd]
dd-6617 [002] 162.914337: block_rq_insert: 253,0 W 0 () 384 + 256 [dd]
dd-6617 [002] 162.914347: block_rq_issue: 253,0 W 0 () 384 + 256 [dd]
**dd-6617 [002] 162.914356: block_rq_remap: 65,176 W 384 + 256 <- (253,0) 384
dd-6617 [002] 162.914358: block_rq_insert: 65,176 W 0 () 384 + 256 [dd]
dd-6617 [002] 162.914359: block_rq_issue: 65,176 W 0 () 384 + 256 [dd]
...
Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Diffstat (limited to 'firmware/cis/tamarack.cis.ihex')
0 files changed, 0 insertions, 0 deletions