| Message ID | 20220125203548.352278-1-shy828301@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v4] block: introduce block_rq_error tracepoint | expand |
On Tue, Jan 25, 2022 at 12:35:48PM -0800, Yang Shi wrote: > Currently, rasdaemon uses the existing tracepoint block_rq_complete > and filters out non-error cases in order to capture block disk errors. > > But there are a few problems with this approach: > > 1. Even kernel trace filter could do the filtering work, there is > still some overhead after we enable this tracepoint. > > 2. The filter is merely based on errno, which does not align with kernel > logic to check the errors for print_req_error(). > > 3. block_rq_complete only provides dev major and minor to identify > the block device, it is not convenient to use in user-space. > > So introduce a new tracepoint block_rq_error just for the error case > and provides the device name for convenience too. With this patch, > rasdaemon could switch to block_rq_error. > > Cc: Jens Axboe <axboe@kernel.dk> > Reviewed-by: Steven Rostedt <rostedt@goodmis.org> > Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> > Signed-off-by: Yang Shi <shy828301@gmail.com> > --- > The v3 patch was submitted in Feb 2020, and Steven reviewed the patch, but > it was not merged to upstream. See > https://lore.kernel.org/lkml/20200203053650.8923-1-xiyou.wangcong@gmail.com/. > > The problems fixed by that patch still exist and we do need it to make > disk error handling in rasdaemon easier. So this resurrected it and > continued the version number. > > v3 --> v4: > * Rebased to v5.17-rc1. > * Collected reviewed-by tag from Steven. > > block/blk-mq.c | 4 +++- > include/trace/events/block.h | 41 ++++++++++++++++++++++++++++++++++++ > 2 files changed, 44 insertions(+), 1 deletion(-) > > diff --git a/block/blk-mq.c b/block/blk-mq.c > index f3bf3358a3bb..bb0593f93675 100644 > --- a/block/blk-mq.c > +++ b/block/blk-mq.c > @@ -789,8 +789,10 @@ bool blk_update_request(struct request *req, blk_status_t error, > #endif > > if (unlikely(error && !blk_rq_is_passthrough(req) && > - !(req->rq_flags & RQF_QUIET))) > + !(req->rq_flags & RQF_QUIET))) { > + trace_block_rq_error(req, blk_status_to_errno(error), nr_bytes); Please report the atual block layer status code instead of the errno mapping here.
On Wed, Jan 26, 2022 at 12:21 AM Christoph Hellwig <hch@infradead.org> wrote: > > On Tue, Jan 25, 2022 at 12:35:48PM -0800, Yang Shi wrote: > > Currently, rasdaemon uses the existing tracepoint block_rq_complete > > and filters out non-error cases in order to capture block disk errors. > > > > But there are a few problems with this approach: > > > > 1. Even kernel trace filter could do the filtering work, there is > > still some overhead after we enable this tracepoint. > > > > 2. The filter is merely based on errno, which does not align with kernel > > logic to check the errors for print_req_error(). > > > > 3. block_rq_complete only provides dev major and minor to identify > > the block device, it is not convenient to use in user-space. > > > > So introduce a new tracepoint block_rq_error just for the error case > > and provides the device name for convenience too. With this patch, > > rasdaemon could switch to block_rq_error. > > > > Cc: Jens Axboe <axboe@kernel.dk> > > Reviewed-by: Steven Rostedt <rostedt@goodmis.org> > > Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> > > Signed-off-by: Yang Shi <shy828301@gmail.com> > > --- > > The v3 patch was submitted in Feb 2020, and Steven reviewed the patch, but > > it was not merged to upstream. See > > https://lore.kernel.org/lkml/20200203053650.8923-1-xiyou.wangcong@gmail.com/. > > > > The problems fixed by that patch still exist and we do need it to make > > disk error handling in rasdaemon easier. So this resurrected it and > > continued the version number. > > > > v3 --> v4: > > * Rebased to v5.17-rc1. > > * Collected reviewed-by tag from Steven. > > > > block/blk-mq.c | 4 +++- > > include/trace/events/block.h | 41 ++++++++++++++++++++++++++++++++++++ > > 2 files changed, 44 insertions(+), 1 deletion(-) > > > > diff --git a/block/blk-mq.c b/block/blk-mq.c > > index f3bf3358a3bb..bb0593f93675 100644 > > --- a/block/blk-mq.c > > +++ b/block/blk-mq.c > > @@ -789,8 +789,10 @@ bool blk_update_request(struct request *req, blk_status_t error, > > #endif > > > > if (unlikely(error && !blk_rq_is_passthrough(req) && > > - !(req->rq_flags & RQF_QUIET))) > > + !(req->rq_flags & RQF_QUIET))) { > > + trace_block_rq_error(req, blk_status_to_errno(error), nr_bytes); > > Please report the atual block layer status code instead of the errno > mapping here. Sure, thanks.
diff --git a/block/blk-mq.c b/block/blk-mq.c index f3bf3358a3bb..bb0593f93675 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -789,8 +789,10 @@ bool blk_update_request(struct request *req, blk_status_t error, #endif if (unlikely(error && !blk_rq_is_passthrough(req) && - !(req->rq_flags & RQF_QUIET))) + !(req->rq_flags & RQF_QUIET))) { + trace_block_rq_error(req, blk_status_to_errno(error), nr_bytes); blk_print_req_error(req, error); + } blk_account_io_completion(req, nr_bytes); diff --git a/include/trace/events/block.h b/include/trace/events/block.h index 27170e40e8c9..3ab6cfe5795a 100644 --- a/include/trace/events/block.h +++ b/include/trace/events/block.h @@ -144,6 +144,47 @@ TRACE_EVENT(block_rq_complete, __entry->nr_sector, __entry->error) ); +/** + * block_rq_error - block IO operation error reported by device driver + * @rq: block operations request + * @error: status code + * @nr_bytes: number of completed bytes + * + * The block_rq_error tracepoint event indicates that some portion + * of operation request has failed as reported by the device driver. + */ +TRACE_EVENT(block_rq_error, + + TP_PROTO(struct request *rq, int error, unsigned int nr_bytes), + + TP_ARGS(rq, error, nr_bytes), + + TP_STRUCT__entry( + __field( dev_t, dev ) + __string( name, rq->q->disk ? rq->q->disk->disk_name : "?") + __field( sector_t, sector ) + __field( unsigned int, nr_sector ) + __field( int, error ) + __array( char, rwbs, RWBS_LEN ) + ), + + TP_fast_assign( + __entry->dev = rq->q->disk ? disk_devt(rq->q->disk) : 0; + __assign_str(name, rq->q->disk ? rq->q->disk->disk_name : "?"); + __entry->sector = blk_rq_pos(rq); + __entry->nr_sector = nr_bytes >> 9; + __entry->error = error; + + blk_fill_rwbs(__entry->rwbs, rq->cmd_flags); + ), + + TP_printk("%d,%d %s %s %llu + %u [%d]", + MAJOR(__entry->dev), MINOR(__entry->dev), + __get_str(name), __entry->rwbs, + (unsigned long long)__entry->sector, + __entry->nr_sector, __entry->error) +); + DECLARE_EVENT_CLASS(block_rq, TP_PROTO(struct request *rq),