| Message ID | 20190206120440.26557-1-jack@suse.cz (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | blktrace: Show requests without sector | expand |
Looks good,
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
On 2/6/19 5:04 AM, Jan Kara wrote: > Currently, blktrace will not show requests that don't have any data as > rq->__sector is initialized to -1 which is out of device range and thus > discarded by act_log_check(). This is most notably the case for cache > flush requests sent to the device. Fix the problem by making > blk_rq_trace_sector() return 0 for requests without initialized sector. Concept is fine, but man, that's not very readable. How about: if (blk_rq_passthrough(rq) || blk_rq_pos(rq) == (sector_t) -1) return 0; return blk_rq_pos(rq); instead? Preferably with a comment on why blk_rq_pos() will be -1.
On Wed 06-02-19 12:49:46, Jens Axboe wrote: > On 2/6/19 5:04 AM, Jan Kara wrote: > > Currently, blktrace will not show requests that don't have any data as > > rq->__sector is initialized to -1 which is out of device range and thus > > discarded by act_log_check(). This is most notably the case for cache > > flush requests sent to the device. Fix the problem by making > > blk_rq_trace_sector() return 0 for requests without initialized sector. > > Concept is fine, but man, that's not very readable. How about: > > if (blk_rq_passthrough(rq) || blk_rq_pos(rq) == (sector_t) -1) > return 0; > > return blk_rq_pos(rq); > > instead? Preferably with a comment on why blk_rq_pos() will be -1. Good points. Will send v2 shortly. Thanks! Honza
diff --git a/include/linux/blktrace_api.h b/include/linux/blktrace_api.h index 8804753805ac..353fd8c70760 100644 --- a/include/linux/blktrace_api.h +++ b/include/linux/blktrace_api.h @@ -116,7 +116,8 @@ extern void blk_fill_rwbs(char *rwbs, unsigned int op, int bytes); static inline sector_t blk_rq_trace_sector(struct request *rq) { - return blk_rq_is_passthrough(rq) ? 0 : blk_rq_pos(rq); + return (blk_rq_is_passthrough(rq) || blk_rq_pos(rq) == (sector_t)-1) ? + 0 : blk_rq_pos(rq); } static inline unsigned int blk_rq_trace_nr_sectors(struct request *rq)
Currently, blktrace will not show requests that don't have any data as rq->__sector is initialized to -1 which is out of device range and thus discarded by act_log_check(). This is most notably the case for cache flush requests sent to the device. Fix the problem by making blk_rq_trace_sector() return 0 for requests without initialized sector. Signed-off-by: Jan Kara <jack@suse.cz> --- include/linux/blktrace_api.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)