| Message ID | 20230520084057.1467003-1-hengqi.chen@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | block: introduce block_io_start/block_io_done tracepoints | expand |
On 5/20/23 1:40 AM, Hengqi Chen wrote: > Currently, several BCC ([0]) tools (biosnoop/biostacks/biotop) use > kprobes to blk_account_io_start/blk_account_io_done to implement > their functionalities. This is fragile because the target kernel > functions may be renamed ([1]) or inlined ([2]). So introduces two > new tracepoints for such use cases. > > [0]: https://github.com/iovisor/bcc > [1]: https://github.com/iovisor/bcc/issues/3954 > [2]: https://github.com/iovisor/bcc/issues/4261 > > Tested-by: Francis Laniel <flaniel@linux.microsoft.com> > Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com> I tested with my local VM, enabled the tracepoint and did see the trace_pipe printout nicely. If the patch is accepted, we will enhance related bcc-tools/libbpf-tools with these tracepoints so they can continue to work with newer kernels. Tested-by: Yonghong Song <yhs@fb.com>
On Sat, 20 May 2023 08:40:57 +0000, Hengqi Chen wrote: > Currently, several BCC ([0]) tools (biosnoop/biostacks/biotop) use > kprobes to blk_account_io_start/blk_account_io_done to implement > their functionalities. This is fragile because the target kernel > functions may be renamed ([1]) or inlined ([2]). So introduces two > new tracepoints for such use cases. > > [0]: https://github.com/iovisor/bcc > [1]: https://github.com/iovisor/bcc/issues/3954 > [2]: https://github.com/iovisor/bcc/issues/4261 > > [...] Applied, thanks! [1/1] block: introduce block_io_start/block_io_done tracepoints commit: 03fcc599757cd74dbcf1a5977f9c6497a6798587 Best regards,
diff --git a/block/blk-mq.c b/block/blk-mq.c index f6dad0886a2f..faa1c7992876 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -957,6 +957,8 @@ EXPORT_SYMBOL_GPL(blk_update_request); static inline void blk_account_io_done(struct request *req, u64 now) { + trace_block_io_done(req); + /* * Account IO completion. flush_rq isn't accounted as a * normal IO on queueing nor completion. Accounting the @@ -976,6 +978,8 @@ static inline void blk_account_io_done(struct request *req, u64 now) static inline void blk_account_io_start(struct request *req) { + trace_block_io_start(req); + if (blk_do_io_stat(req)) { /* * All non-passthrough requests are created from a bio with one diff --git a/include/trace/events/block.h b/include/trace/events/block.h index 7f4dfbdf12a6..40e60c33cc6f 100644 --- a/include/trace/events/block.h +++ b/include/trace/events/block.h @@ -245,6 +245,32 @@ DEFINE_EVENT(block_rq, block_rq_merge, TP_ARGS(rq) ); +/** + * block_io_start - insert a request for execution + * @rq: block IO operation request + * + * Called when block operation request @rq is queued for execution + */ +DEFINE_EVENT(block_rq, block_io_start, + + TP_PROTO(struct request *rq), + + TP_ARGS(rq) +); + +/** + * block_io_done - block IO operation request completed + * @rq: block IO operation request + * + * Called when block operation request @rq is completed + */ +DEFINE_EVENT(block_rq, block_io_done, + + TP_PROTO(struct request *rq), + + TP_ARGS(rq) +); + /** * block_bio_complete - completed all work on the block operation * @q: queue holding the block operation