Jan Kara f3bdc62fd8 blktrace: Provide event for request merging ... Currently blk-mq does not report any event when two requests get merged in the elevator. This then results in difficult to understand sequence of events like: ... 8,0 34 1579 0.608765271 2718 I WS 215023504 + 40 [dbench] 8,0 34 1584 0.609184613 2719 A WS 215023544 + 56 <- (8,4) 2160568 8,0 34 1585 0.609184850 2719 Q WS 215023544 + 56 [dbench] 8,0 34 1586 0.609188524 2719 G WS 215023544 + 56 [dbench] 8,0 3 602 0.609684162 773 D WS 215023504 + 96 [kworker/3:1H] 8,0 34 1591 0.609843593 0 C WS 215023504 + 96 [0] and you can only guess (after quite some headscratching since the above excerpt is intermixed with a lot of other IO) that request 215023544+56 got merged to request 215023504+40. Provide proper event for request merging like we used to do in the legacy block layer. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Jens Axboe <axboe@kernel.dk>		2020-06-25 21:06:11 -06:00
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events	blktrace: Provide event for request merging	2020-06-25 21:06:11 -06:00
bpf_probe.h	bpf: Reliably preserve btf_trace_xxx types	2020-03-02 16:49:55 -08:00
define_trace.h	tracing: introduce TRACE_EVENT_NOP()	2019-04-08 09:22:51 -04:00
perf.h	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net	2017-11-04 09:26:51 +09:00
syscall.h	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
trace_events.h	Tracing updates:	2020-02-06 07:12:11 +00:00