| Message ID | 158290150891.4423.13566449569964563258.stgit@buzz (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | block: keep bdi->io_pages in sync with max_sectors_kb for stacked devices | expand |
Dear Konstantin, Thank you for the patch. On 2020-02-28 15:51, Konstantin Khlebnikov wrote: > Field bdi->io_pages added in commit 9491ae4aade6 ("mm: don't cap request > size based on read-ahead setting") removes unneeded split of read requests. > > Stacked drivers do not call blk_queue_max_hw_sectors(). Instead they setup The verb is spelled with a space *set up*. > limits of their devices by blk_set_stacking_limits() + disk_stack_limits(). > Field bio->io_pages stays zero until user set max_sectors_kb via sysfs. > > This patch updates io_pages after merging limits in disk_stack_limits(). > > Commit c6d6e9b0f6b4 ("dm: do not allow readahead to limit IO size") fixed > the same problem for device-mapper devices, this one fixes MD RAIDs. Add a Fixes: tag? Fixes: 9491ae4aade6 ("mm: don't cap request size based on read-ahead setting") > Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> > --- > block/blk-settings.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/block/blk-settings.c b/block/blk-settings.c > index c8eda2e7b91e..66c45fd79545 100644 > --- a/block/blk-settings.c > +++ b/block/blk-settings.c > @@ -664,6 +664,8 @@ void disk_stack_limits(struct gendisk *disk, struct block_device *bdev, > printk(KERN_NOTICE "%s: Warning: Device %s is misaligned\n", > top, bottom); > } > + > + t->backing_dev_info->io_pages = t->limits.max_sectors >> (PAGE_SHIFT-9); > } > EXPORT_SYMBOL(disk_stack_limits); Reviewed-by: Paul Menzel <pmenzel@molgen.mpg.de> Kind regards, Paul
On 02/03/2020 13.41, Paul Menzel wrote: > Dear Konstantin, > > > Thank you for the patch. > > > On 2020-02-28 15:51, Konstantin Khlebnikov wrote: >> Field bdi->io_pages added in commit 9491ae4aade6 ("mm: don't cap request >> size based on read-ahead setting") removes unneeded split of read requests. >> >> Stacked drivers do not call blk_queue_max_hw_sectors(). Instead they setup > > The verb is spelled with a space *set up*. > >> limits of their devices by blk_set_stacking_limits() + disk_stack_limits(). >> Field bio->io_pages stays zero until user set max_sectors_kb via sysfs. >> >> This patch updates io_pages after merging limits in disk_stack_limits(). >> >> Commit c6d6e9b0f6b4 ("dm: do not allow readahead to limit IO size") fixed >> the same problem for device-mapper devices, this one fixes MD RAIDs. > > Add a Fixes: tag? > > Fixes: 9491ae4aade6 ("mm: don't cap request size based on read-ahead setting") Maybe, but this isn't fatal bug. Just incomplete fix. Same problem exists for non-disk BDIs. I.e. network filesystem must set io_pages manually if doesn't want split read requests. > >> Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> >> --- >> block/blk-settings.c | 2 ++ >> 1 file changed, 2 insertions(+) >> >> diff --git a/block/blk-settings.c b/block/blk-settings.c >> index c8eda2e7b91e..66c45fd79545 100644 >> --- a/block/blk-settings.c >> +++ b/block/blk-settings.c >> @@ -664,6 +664,8 @@ void disk_stack_limits(struct gendisk *disk, struct block_device *bdev, >> printk(KERN_NOTICE "%s: Warning: Device %s is misaligned\n", >> top, bottom); >> } >> + >> + t->backing_dev_info->io_pages = t->limits.max_sectors >> (PAGE_SHIFT-9); >> } >> EXPORT_SYMBOL(disk_stack_limits); > > Reviewed-by: Paul Menzel <pmenzel@molgen.mpg.de> > > > Kind regards, > > Paul >
On 2/28/20 10:51 PM, Konstantin Khlebnikov wrote: > Field bdi->io_pages added in commit 9491ae4aade6 ("mm: don't cap request > size based on read-ahead setting") removes unneeded split of read requests. > > Stacked drivers do not call blk_queue_max_hw_sectors(). Instead they setup > limits of their devices by blk_set_stacking_limits() + disk_stack_limits(). > Field bio->io_pages stays zero until user set max_sectors_kb via sysfs. > > This patch updates io_pages after merging limits in disk_stack_limits(). > > Commit c6d6e9b0f6b4 ("dm: do not allow readahead to limit IO size") fixed > the same problem for device-mapper devices, this one fixes MD RAIDs. > > Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> > --- > block/blk-settings.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/block/blk-settings.c b/block/blk-settings.c > index c8eda2e7b91e..66c45fd79545 100644 > --- a/block/blk-settings.c > +++ b/block/blk-settings.c > @@ -664,6 +664,8 @@ void disk_stack_limits(struct gendisk *disk, struct block_device *bdev, > printk(KERN_NOTICE "%s: Warning: Device %s is misaligned\n", > top, bottom); > } > + > + t->backing_dev_info->io_pages = t->limits.max_sectors >> (PAGE_SHIFT-9); > } > EXPORT_SYMBOL(disk_stack_limits); > > Nitpick.. (PAGE_SHIFT - 9) Reviewed-by: Bob Liu <bob.liu@oracle.com>
On Mon, Mar 2, 2020 at 4:16 AM Bob Liu <bob.liu@oracle.com> wrote: > > On 2/28/20 10:51 PM, Konstantin Khlebnikov wrote: > > Field bdi->io_pages added in commit 9491ae4aade6 ("mm: don't cap request > > size based on read-ahead setting") removes unneeded split of read requests. > > > > Stacked drivers do not call blk_queue_max_hw_sectors(). Instead they setup > > limits of their devices by blk_set_stacking_limits() + disk_stack_limits(). > > Field bio->io_pages stays zero until user set max_sectors_kb via sysfs. > > > > This patch updates io_pages after merging limits in disk_stack_limits(). > > > > Commit c6d6e9b0f6b4 ("dm: do not allow readahead to limit IO size") fixed > > the same problem for device-mapper devices, this one fixes MD RAIDs. > > > > Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> > > --- > > block/blk-settings.c | 2 ++ > > 1 file changed, 2 insertions(+) > > > > diff --git a/block/blk-settings.c b/block/blk-settings.c > > index c8eda2e7b91e..66c45fd79545 100644 > > --- a/block/blk-settings.c > > +++ b/block/blk-settings.c > > @@ -664,6 +664,8 @@ void disk_stack_limits(struct gendisk *disk, struct block_device *bdev, > > printk(KERN_NOTICE "%s: Warning: Device %s is misaligned\n", > > top, bottom); > > } > > + > > + t->backing_dev_info->io_pages = t->limits.max_sectors >> (PAGE_SHIFT-9); > > } > > EXPORT_SYMBOL(disk_stack_limits); > > > > > > Nitpick.. (PAGE_SHIFT - 9) > Reviewed-by: Bob Liu <bob.liu@oracle.com> Thanks for the fix. I fixed it based on the comments and applied it to md-next. Jens, I picked the patch to md-next because md is the only user of disk_stack_limits(). Please let me know if you prefer routing it via the block tree. Thanks, Song
On 3/10/20 3:40 PM, Song Liu wrote: > On Mon, Mar 2, 2020 at 4:16 AM Bob Liu <bob.liu@oracle.com> wrote: >> >> On 2/28/20 10:51 PM, Konstantin Khlebnikov wrote: >>> Field bdi->io_pages added in commit 9491ae4aade6 ("mm: don't cap request >>> size based on read-ahead setting") removes unneeded split of read requests. >>> >>> Stacked drivers do not call blk_queue_max_hw_sectors(). Instead they setup >>> limits of their devices by blk_set_stacking_limits() + disk_stack_limits(). >>> Field bio->io_pages stays zero until user set max_sectors_kb via sysfs. >>> >>> This patch updates io_pages after merging limits in disk_stack_limits(). >>> >>> Commit c6d6e9b0f6b4 ("dm: do not allow readahead to limit IO size") fixed >>> the same problem for device-mapper devices, this one fixes MD RAIDs. >>> >>> Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> >>> --- >>> block/blk-settings.c | 2 ++ >>> 1 file changed, 2 insertions(+) >>> >>> diff --git a/block/blk-settings.c b/block/blk-settings.c >>> index c8eda2e7b91e..66c45fd79545 100644 >>> --- a/block/blk-settings.c >>> +++ b/block/blk-settings.c >>> @@ -664,6 +664,8 @@ void disk_stack_limits(struct gendisk *disk, struct block_device *bdev, >>> printk(KERN_NOTICE "%s: Warning: Device %s is misaligned\n", >>> top, bottom); >>> } >>> + >>> + t->backing_dev_info->io_pages = t->limits.max_sectors >> (PAGE_SHIFT-9); >>> } >>> EXPORT_SYMBOL(disk_stack_limits); >>> >>> >> >> Nitpick.. (PAGE_SHIFT - 9) >> Reviewed-by: Bob Liu <bob.liu@oracle.com> > > Thanks for the fix. I fixed it based on the comments and applied it to md-next. > > Jens, I picked the patch to md-next because md is the only user of > disk_stack_limits(). > > Please let me know if you prefer routing it via the block tree. That's fine, thanks.
diff --git a/block/blk-settings.c b/block/blk-settings.c index c8eda2e7b91e..66c45fd79545 100644 --- a/block/blk-settings.c +++ b/block/blk-settings.c @@ -664,6 +664,8 @@ void disk_stack_limits(struct gendisk *disk, struct block_device *bdev, printk(KERN_NOTICE "%s: Warning: Device %s is misaligned\n", top, bottom); } + + t->backing_dev_info->io_pages = t->limits.max_sectors >> (PAGE_SHIFT-9); } EXPORT_SYMBOL(disk_stack_limits);
Field bdi->io_pages added in commit 9491ae4aade6 ("mm: don't cap request size based on read-ahead setting") removes unneeded split of read requests. Stacked drivers do not call blk_queue_max_hw_sectors(). Instead they setup limits of their devices by blk_set_stacking_limits() + disk_stack_limits(). Field bio->io_pages stays zero until user set max_sectors_kb via sysfs. This patch updates io_pages after merging limits in disk_stack_limits(). Commit c6d6e9b0f6b4 ("dm: do not allow readahead to limit IO size") fixed the same problem for device-mapper devices, this one fixes MD RAIDs. Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> --- block/blk-settings.c | 2 ++ 1 file changed, 2 insertions(+)