On 9/21/18 2:56 PM, Dennis Zhou wrote: > Hi Jens, > > On Tue, Sep 11, 2018 at 02:41:25PM -0400, Dennis Zhou wrote: >> Hi everyone, >> >> v3: a few minor fixes. >> 0003: Updated the comment to bio_associate_blkg to reflect closest >> association. >> Removed a return branch in __bio_lookup_create. >> 0009: Removed an unnecessary rcu_read_(un)lock pair. >> 0010: Fixed blkg null pointer... blkg->blkcg => blkcg. >> >> This is rebased onto axboe#for-4.20/block 902d53914f64. >> >> From v2 below (updated): >> ------ >> This is a followup to the patch series I sent out earlier [1] containing >> the middle two points: >> 1. always associate a bio with a blkg >> 2. remove the extra css ref held by bios and utilize the blkg ref >> >> The major difference with v2 is that error handling on blkg creation >> and association failure is handled more gracefully. Rather than having >> the complex logic to fallback to root, failures walk up the blkg tree. >> This seems more natural and less prone to error with the many possible >> failure scenarios. >> >> Additionally, there are fixes for kbuild errors and some key details >> overlooked by me in the first series that were pointed out in review. >> >> Modified from the first patchset: >> First, both blk-throttle and blk-iolatency rely on blkg association >> to enable their policies. Rather than each policy (and future policies) >> implement this logic independently, this consolidates it such that >> all bios are tagged with a blkg. >> >> Second, with the addition of always having a blkg reference, the blkcg >> can now be referenced through it rather than maintaining an additional >> pointer and reference. So let's clean this up. >> >> [1] https://lore.kernel.org/lkml/20180831015356.69796-1-dennisszhou@xxxxxxxxx/T >> >> This patchset contains the following 12 patches: >> 0001-blkcg-fix-ref-count-issue-with-bio_blkcg-using-task_.patch >> 0002-blkcg-update-blkg_lookup_create-to-do-locking.patch >> 0003-blkcg-convert-blkg_lookup_create-to-find-closest-blk.patch >> 0004-blkcg-always-associate-a-bio-with-a-blkg.patch >> 0005-blkcg-consolidate-bio_issue_init-to-be-a-part-of-cor.patch >> 0006-blkcg-associate-a-blkg-for-pages-being-evicted-by-sw.patch >> 0007-blkcg-associate-writeback-bios-with-a-blkg.patch >> 0008-blkcg-remove-bio-bi_css-and-instead-use-bio-bi_blkg.patch >> 0009-blkcg-remove-additional-reference-to-the-css.patch >> 0010-blkcg-cleanup-and-make-blk_get_rl-use-blkg_lookup_cr.patch >> 0011-blkcg-change-blkg-reference-counting-to-use-percpu_r.patch >> 0012-blkcg-rename-blkg_try_get-to-blkg_tryget.patch >> >> This patchset is on top of axboe#for-4.20/block 902d53914f64. >> >> diffstats below: >> >> Dennis Zhou (Facebook) (12): >> blkcg: fix ref count issue with bio_blkcg using task_css >> blkcg: update blkg_lookup_create to do locking >> blkcg: convert blkg_lookup_create to find closest blkg >> blkcg: always associate a bio with a blkg >> blkcg: consolidate bio_issue_init to be a part of core >> blkcg: associate a blkg for pages being evicted by swap >> blkcg: associate writeback bios with a blkg >> blkcg: remove bio->bi_css and instead use bio->bi_blkg >> blkcg: remove additional reference to the css >> blkcg: cleanup and make blk_get_rl use blkg_lookup_create >> blkcg: change blkg reference counting to use percpu_ref >> blkcg: rename blkg_try_get to blkg_tryget >> >> Documentation/admin-guide/cgroup-v2.rst | 8 +- >> block/bfq-cgroup.c | 4 +- >> block/bfq-iosched.c | 2 +- >> block/bio.c | 158 ++++++++++++++++-------- >> block/blk-cgroup.c | 123 ++++++++++++------ >> block/blk-iolatency.c | 26 +--- >> block/blk-throttle.c | 13 +- >> block/bounce.c | 4 +- >> block/cfq-iosched.c | 4 +- >> drivers/block/loop.c | 5 +- >> drivers/md/raid0.c | 2 +- >> fs/buffer.c | 10 +- >> fs/ext4/page-io.c | 2 +- >> include/linux/bio.h | 23 ++-- >> include/linux/blk-cgroup.h | 145 +++++++++++++++------- >> include/linux/blk_types.h | 1 - >> include/linux/cgroup.h | 2 + >> include/linux/writeback.h | 5 +- >> kernel/cgroup/cgroup.c | 48 +++++-- >> kernel/trace/blktrace.c | 4 +- >> mm/page_io.c | 2 +- >> 21 files changed, 381 insertions(+), 210 deletions(-) >> >> Thanks, >> Dennis > > I reran some basic test again for sanity and it seems to be fine on my > end. There are at least acks, and some reviewed-by's on the series. Is > there anything else you think needs to be done before we let this bake > in for-4.20/for-next? Looks like it's good to go, I have applied it for 4.20. Thanks Dennis. -- Jens Axboe
