Ritesh Harjani (IBM) <ritesh.list@xxxxxxxxx> writes: > John Garry <john.g.garry@xxxxxxxxxx> writes: > >> On 03/04/2025 06:28, Ritesh Harjani (IBM) wrote: >>> Filesystems like XFS can implement atomic write I/O using either REQ_ATOMIC >>> flag set in the bio or via CoW operation. It will be useful if we have a >>> flag in trace events to distinguish between the two. >> >> I suppose that this could be useful. So far I test with block driver >> traces, i.e. NVMe or SCSI internal traces, just to ensure that we see >> the requests sent as expected >> > > Right. > >> This patch adds >>> char 'a' to rwbs field of the trace events if REQ_ATOMIC flag is set in >>> the bio. >> >> All others use uppercase characters, so I suggest that you continue to >> use that. > > It will be good to know on whether only uppercase characters are allowed > or we are good with smallcase characters too? > >> Since 'A' is already used, how about 'U' for untorn? Or 'T' >> for aTOMic :) >> > > If 'a' is not allowed, then we can change it to 'T' maybe. > Gentle ping on this.. Any comments/feedback? It will be good to have these trace events with an identifier to differentiate between reqs/bios submitted with REQ_ATOMIC flag. -ritesh > -ritesh > > >>> >>> <W/ REQ_ATOMIC> >>> ================= >>> xfs_io-1107 [002] ..... 406.206441: block_rq_issue: 8,48 WSa 16384 () 768 + 32 none,0,0 [xfs_io] >>> <idle>-0 [002] ..s1. 406.209918: block_rq_complete: 8,48 WSa () 768 + 32 none,0,0 [0] >>> >>> <W/O REQ_ATOMIC> >>> =============== >>> xfs_io-1108 [002] ..... 411.212317: block_rq_issue: 8,48 WS 16384 () 1024 + 32 none,0,0 [xfs_io] >>> <idle>-0 [002] ..s1. 411.215842: block_rq_complete: 8,48 WS () 1024 + 32 none,0,0 [0] >>>
