| Message ID | 20181012023012.29923-10-damien.lemoal@wdc.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Zoned block device support improvements | expand |
On 10/12/18 4:30 AM, Damien Le Moal wrote: > Expose through sysfs the nr_zones field of struct request_queue. > Exposing this value helps in debugging disk issues as well as > facilitating scripts based use of the disk (e.g. blktests). > > For zoned block devices, the nr_zones field indicates the total number > of zones of the device calculated using the known disk capacity and > zone size. This number of zones is always 0 for regular block devices. > > Since nr_zones is defined conditionally with CONFIG_BLK_DEV_ZONED, > introduce the blk_queue_nr_zones() function to return the correct value > for any device, regardless if CONFIG_BLK_DEV_ZONED is set. > > Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> > --- > block/blk-sysfs.c | 11 +++++++++++ > include/linux/blkdev.h | 10 ++++++++++ > 2 files changed, 21 insertions(+) > > diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c > index 3772671cf2bc..92be8092ca4f 100644 > --- a/block/blk-sysfs.c > +++ b/block/blk-sysfs.c > @@ -300,6 +300,11 @@ static ssize_t queue_zoned_show(struct request_queue *q, char *page) > } > } > > +static ssize_t queue_nr_zones_show(struct request_queue *q, char *page) > +{ > + return queue_var_show(blk_queue_nr_zones(q), page); > +} > + > static ssize_t queue_nomerges_show(struct request_queue *q, char *page) > { > return queue_var_show((blk_queue_nomerges(q) << 1) | > @@ -637,6 +642,11 @@ static struct queue_sysfs_entry queue_zoned_entry = { > .show = queue_zoned_show, > }; > > +static struct queue_sysfs_entry queue_nr_zones_entry = { > + .attr = {.name = "nr_zones", .mode = 0444 }, > + .show = queue_nr_zones_show, > +}; > + > static struct queue_sysfs_entry queue_nomerges_entry = { > .attr = {.name = "nomerges", .mode = 0644 }, > .show = queue_nomerges_show, > @@ -727,6 +737,7 @@ static struct attribute *default_attrs[] = { > &queue_write_zeroes_max_entry.attr, > &queue_nonrot_entry.attr, > &queue_zoned_entry.attr, > + &queue_nr_zones_entry.attr, > &queue_nomerges_entry.attr, > &queue_rq_affinity_entry.attr, > &queue_iostats_entry.attr, > diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h > index c24969b1741b..879753b10263 100644 > --- a/include/linux/blkdev.h > +++ b/include/linux/blkdev.h > @@ -804,6 +804,11 @@ static inline unsigned int blk_queue_zone_sectors(struct request_queue *q) > } > > #ifdef CONFIG_BLK_DEV_ZONED > +static inline unsigned int blk_queue_nr_zones(struct request_queue *q) > +{ > + return blk_queue_is_zoned(q) ? q->nr_zones : 0; > +} > + > static inline unsigned int blk_queue_zone_no(struct request_queue *q, > sector_t sector) > { > @@ -819,6 +824,11 @@ static inline bool blk_queue_zone_is_seq(struct request_queue *q, > return false; > return test_bit(blk_queue_zone_no(q, sector), q->seq_zones_bitmap); > } > +#else /* CONFIG_BLK_DEV_ZONED */ > +static inline unsigned int blk_queue_nr_zones(struct request_queue *q) > +{ > + return 0; > +} > #endif /* CONFIG_BLK_DEV_ZONED */ > > static inline bool rq_is_sync(struct request *rq) > Actually, we should be checking whether we can't blank out this attribute via the is_visible mechanism; after all, not every block device is zoned, and those which are not have no need of the attribute... Cheers, Hannes
On 2018/10/12 16:41, Hannes Reinecke wrote: > On 10/12/18 4:30 AM, Damien Le Moal wrote: >> Expose through sysfs the nr_zones field of struct request_queue. >> Exposing this value helps in debugging disk issues as well as >> facilitating scripts based use of the disk (e.g. blktests). >> >> For zoned block devices, the nr_zones field indicates the total number >> of zones of the device calculated using the known disk capacity and >> zone size. This number of zones is always 0 for regular block devices. >> >> Since nr_zones is defined conditionally with CONFIG_BLK_DEV_ZONED, >> introduce the blk_queue_nr_zones() function to return the correct value >> for any device, regardless if CONFIG_BLK_DEV_ZONED is set. >> >> Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> >> --- >> block/blk-sysfs.c | 11 +++++++++++ >> include/linux/blkdev.h | 10 ++++++++++ >> 2 files changed, 21 insertions(+) >> >> diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c >> index 3772671cf2bc..92be8092ca4f 100644 >> --- a/block/blk-sysfs.c >> +++ b/block/blk-sysfs.c >> @@ -300,6 +300,11 @@ static ssize_t queue_zoned_show(struct request_queue *q, char *page) >> } >> } >> >> +static ssize_t queue_nr_zones_show(struct request_queue *q, char *page) >> +{ >> + return queue_var_show(blk_queue_nr_zones(q), page); >> +} >> + >> static ssize_t queue_nomerges_show(struct request_queue *q, char *page) >> { >> return queue_var_show((blk_queue_nomerges(q) << 1) | >> @@ -637,6 +642,11 @@ static struct queue_sysfs_entry queue_zoned_entry = { >> .show = queue_zoned_show, >> }; >> >> +static struct queue_sysfs_entry queue_nr_zones_entry = { >> + .attr = {.name = "nr_zones", .mode = 0444 }, >> + .show = queue_nr_zones_show, >> +}; >> + >> static struct queue_sysfs_entry queue_nomerges_entry = { >> .attr = {.name = "nomerges", .mode = 0644 }, >> .show = queue_nomerges_show, >> @@ -727,6 +737,7 @@ static struct attribute *default_attrs[] = { >> &queue_write_zeroes_max_entry.attr, >> &queue_nonrot_entry.attr, >> &queue_zoned_entry.attr, >> + &queue_nr_zones_entry.attr, >> &queue_nomerges_entry.attr, >> &queue_rq_affinity_entry.attr, >> &queue_iostats_entry.attr, >> diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h >> index c24969b1741b..879753b10263 100644 >> --- a/include/linux/blkdev.h >> +++ b/include/linux/blkdev.h >> @@ -804,6 +804,11 @@ static inline unsigned int blk_queue_zone_sectors(struct request_queue *q) >> } >> >> #ifdef CONFIG_BLK_DEV_ZONED >> +static inline unsigned int blk_queue_nr_zones(struct request_queue *q) >> +{ >> + return blk_queue_is_zoned(q) ? q->nr_zones : 0; >> +} >> + >> static inline unsigned int blk_queue_zone_no(struct request_queue *q, >> sector_t sector) >> { >> @@ -819,6 +824,11 @@ static inline bool blk_queue_zone_is_seq(struct request_queue *q, >> return false; >> return test_bit(blk_queue_zone_no(q, sector), q->seq_zones_bitmap); >> } >> +#else /* CONFIG_BLK_DEV_ZONED */ >> +static inline unsigned int blk_queue_nr_zones(struct request_queue *q) >> +{ >> + return 0; >> +} >> #endif /* CONFIG_BLK_DEV_ZONED */ >> >> static inline bool rq_is_sync(struct request *rq) >> > Actually, we should be checking whether we can't blank out this > attribute via the is_visible mechanism; after all, not every block > device is zoned, and those which are not have no need of the attribute... Yes we could. But it is somewhat the same as drives that do not support trim: they get max_discard_sectors to 0. The attribute says "not supported because the value is 0". I followed the same principle for nr_zones: value of 0 says "no zones", hopefully in sync with "zoned" saying "none". And if these 2 are not in sync as such, then we have a defective drive or a bug. So actually always having nr_zones is useful I think. But I can make it invisible for regular disks if you insist :)
On Fri, Oct 12, 2018 at 09:41:28AM +0200, Hannes Reinecke wrote: >> +{ >> + return 0; >> +} >> #endif /* CONFIG_BLK_DEV_ZONED */ >> static inline bool rq_is_sync(struct request *rq) >> > Actually, we should be checking whether we can't blank out this attribute > via the is_visible mechanism; after all, not every block device is zoned, > and those which are not have no need of the attribute... The answer would be 0 in this case. I'm not sure blanking out is worth it as it will create a lot more code for very little gain..
On Fri, Oct 12, 2018 at 11:30:10AM +0900, Damien Le Moal wrote: > Expose through sysfs the nr_zones field of struct request_queue. > Exposing this value helps in debugging disk issues as well as > facilitating scripts based use of the disk (e.g. blktests). > > For zoned block devices, the nr_zones field indicates the total number > of zones of the device calculated using the known disk capacity and > zone size. This number of zones is always 0 for regular block devices. > > Since nr_zones is defined conditionally with CONFIG_BLK_DEV_ZONED, > introduce the blk_queue_nr_zones() function to return the correct value > for any device, regardless if CONFIG_BLK_DEV_ZONED is set. > > Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Looks good, Reviewed-by: Christoph Hellwig <hch@lst.de>
On 10/12/18 9:55 AM, Damien Le Moal wrote: > On 2018/10/12 16:41, Hannes Reinecke wrote: >> On 10/12/18 4:30 AM, Damien Le Moal wrote: >>> Expose through sysfs the nr_zones field of struct request_queue. >>> Exposing this value helps in debugging disk issues as well as >>> facilitating scripts based use of the disk (e.g. blktests). >>> >>> For zoned block devices, the nr_zones field indicates the total number >>> of zones of the device calculated using the known disk capacity and >>> zone size. This number of zones is always 0 for regular block devices. >>> >>> Since nr_zones is defined conditionally with CONFIG_BLK_DEV_ZONED, >>> introduce the blk_queue_nr_zones() function to return the correct value >>> for any device, regardless if CONFIG_BLK_DEV_ZONED is set. >>> >>> Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> >>> --- >>> block/blk-sysfs.c | 11 +++++++++++ >>> include/linux/blkdev.h | 10 ++++++++++ >>> 2 files changed, 21 insertions(+) >>> >>> diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c >>> index 3772671cf2bc..92be8092ca4f 100644 >>> --- a/block/blk-sysfs.c >>> +++ b/block/blk-sysfs.c >>> @@ -300,6 +300,11 @@ static ssize_t queue_zoned_show(struct request_queue *q, char *page) >>> } >>> } >>> >>> +static ssize_t queue_nr_zones_show(struct request_queue *q, char *page) >>> +{ >>> + return queue_var_show(blk_queue_nr_zones(q), page); >>> +} >>> + >>> static ssize_t queue_nomerges_show(struct request_queue *q, char *page) >>> { >>> return queue_var_show((blk_queue_nomerges(q) << 1) | >>> @@ -637,6 +642,11 @@ static struct queue_sysfs_entry queue_zoned_entry = { >>> .show = queue_zoned_show, >>> }; >>> >>> +static struct queue_sysfs_entry queue_nr_zones_entry = { >>> + .attr = {.name = "nr_zones", .mode = 0444 }, >>> + .show = queue_nr_zones_show, >>> +}; >>> + >>> static struct queue_sysfs_entry queue_nomerges_entry = { >>> .attr = {.name = "nomerges", .mode = 0644 }, >>> .show = queue_nomerges_show, >>> @@ -727,6 +737,7 @@ static struct attribute *default_attrs[] = { >>> &queue_write_zeroes_max_entry.attr, >>> &queue_nonrot_entry.attr, >>> &queue_zoned_entry.attr, >>> + &queue_nr_zones_entry.attr, >>> &queue_nomerges_entry.attr, >>> &queue_rq_affinity_entry.attr, >>> &queue_iostats_entry.attr, >>> diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h >>> index c24969b1741b..879753b10263 100644 >>> --- a/include/linux/blkdev.h >>> +++ b/include/linux/blkdev.h >>> @@ -804,6 +804,11 @@ static inline unsigned int blk_queue_zone_sectors(struct request_queue *q) >>> } >>> >>> #ifdef CONFIG_BLK_DEV_ZONED >>> +static inline unsigned int blk_queue_nr_zones(struct request_queue *q) >>> +{ >>> + return blk_queue_is_zoned(q) ? q->nr_zones : 0; >>> +} >>> + >>> static inline unsigned int blk_queue_zone_no(struct request_queue *q, >>> sector_t sector) >>> { >>> @@ -819,6 +824,11 @@ static inline bool blk_queue_zone_is_seq(struct request_queue *q, >>> return false; >>> return test_bit(blk_queue_zone_no(q, sector), q->seq_zones_bitmap); >>> } >>> +#else /* CONFIG_BLK_DEV_ZONED */ >>> +static inline unsigned int blk_queue_nr_zones(struct request_queue *q) >>> +{ >>> + return 0; >>> +} >>> #endif /* CONFIG_BLK_DEV_ZONED */ >>> >>> static inline bool rq_is_sync(struct request *rq) >>> >> Actually, we should be checking whether we can't blank out this >> attribute via the is_visible mechanism; after all, not every block >> device is zoned, and those which are not have no need of the attribute... > > Yes we could. But it is somewhat the same as drives that do not support trim: > they get max_discard_sectors to 0. The attribute says "not supported because the > value is 0". I followed the same principle for nr_zones: value of 0 says "no > zones", hopefully in sync with "zoned" saying "none". And if these 2 are not in > sync as such, then we have a defective drive or a bug. So actually always having > nr_zones is useful I think. > > But I can make it invisible for regular disks if you insist :) > I don't mind; but then I might be zbc-biased already. Leave up to the maintainers to decide. Hence: Reviewed-by: Hannes Reinecke <hare@suse.com> Cheers, Hannes
diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index 3772671cf2bc..92be8092ca4f 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -300,6 +300,11 @@ static ssize_t queue_zoned_show(struct request_queue *q, char *page) } } +static ssize_t queue_nr_zones_show(struct request_queue *q, char *page) +{ + return queue_var_show(blk_queue_nr_zones(q), page); +} + static ssize_t queue_nomerges_show(struct request_queue *q, char *page) { return queue_var_show((blk_queue_nomerges(q) << 1) | @@ -637,6 +642,11 @@ static struct queue_sysfs_entry queue_zoned_entry = { .show = queue_zoned_show, }; +static struct queue_sysfs_entry queue_nr_zones_entry = { + .attr = {.name = "nr_zones", .mode = 0444 }, + .show = queue_nr_zones_show, +}; + static struct queue_sysfs_entry queue_nomerges_entry = { .attr = {.name = "nomerges", .mode = 0644 }, .show = queue_nomerges_show, @@ -727,6 +737,7 @@ static struct attribute *default_attrs[] = { &queue_write_zeroes_max_entry.attr, &queue_nonrot_entry.attr, &queue_zoned_entry.attr, + &queue_nr_zones_entry.attr, &queue_nomerges_entry.attr, &queue_rq_affinity_entry.attr, &queue_iostats_entry.attr, diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index c24969b1741b..879753b10263 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -804,6 +804,11 @@ static inline unsigned int blk_queue_zone_sectors(struct request_queue *q) } #ifdef CONFIG_BLK_DEV_ZONED +static inline unsigned int blk_queue_nr_zones(struct request_queue *q) +{ + return blk_queue_is_zoned(q) ? q->nr_zones : 0; +} + static inline unsigned int blk_queue_zone_no(struct request_queue *q, sector_t sector) { @@ -819,6 +824,11 @@ static inline bool blk_queue_zone_is_seq(struct request_queue *q, return false; return test_bit(blk_queue_zone_no(q, sector), q->seq_zones_bitmap); } +#else /* CONFIG_BLK_DEV_ZONED */ +static inline unsigned int blk_queue_nr_zones(struct request_queue *q) +{ + return 0; +} #endif /* CONFIG_BLK_DEV_ZONED */ static inline bool rq_is_sync(struct request *rq)
Expose through sysfs the nr_zones field of struct request_queue. Exposing this value helps in debugging disk issues as well as facilitating scripts based use of the disk (e.g. blktests). For zoned block devices, the nr_zones field indicates the total number of zones of the device calculated using the known disk capacity and zone size. This number of zones is always 0 for regular block devices. Since nr_zones is defined conditionally with CONFIG_BLK_DEV_ZONED, introduce the blk_queue_nr_zones() function to return the correct value for any device, regardless if CONFIG_BLK_DEV_ZONED is set. Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> --- block/blk-sysfs.c | 11 +++++++++++ include/linux/blkdev.h | 10 ++++++++++ 2 files changed, 21 insertions(+)