]> git.baikalelectronics.ru Git - kernel.git/commit
block: fix trace completion for chained bio
authorEdward Hsieh <edwardh@synology.com>
Thu, 24 Jun 2021 12:30:30 +0000 (20:30 +0800)
committerJens Axboe <axboe@kernel.dk>
Thu, 24 Jun 2021 15:53:50 +0000 (09:53 -0600)
commit60b6a7e6a0f4382cd689f9afdac816964fec2921
tree7b5fd7251cbc4c3430b61ff3b641b651bc1f6da4
parentddcc5c544eb0991501761622b651cf43ce660a22
block: fix trace completion for chained bio

For chained bio, trace_block_bio_complete in bio_endio is currently called
only by the parent bio once upon all chained bio completed.
However, the sector and size for the parent bio are modified in bio_split.
Therefore, the size and sector of the complete events might not match the
queue events in blktrace.

The original fix of bio completion trace <fbbaf700e7b1> ("block: trace
completion of all bios.") wants multiple complete events to correspond
to one queue event but missed this.

The issue can be reproduced by md/raid5 read with bio cross chunks.

To fix, move trace completion into the loop for every chained bio to call.

Fixes: fbbaf700e7b1 ("block: trace completion of all bios.")
Reviewed-by: Wade Liang <wadel@synology.com>
Reviewed-by: BingJing Chang <bingjingc@synology.com>
Signed-off-by: Edward Hsieh <edwardh@synology.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20210624123030.27014-1-edwardh@synology.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
block/bio.c