| Message ID | 20180703151503.2549-6-josef@toxicpanda.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 07/03/2018 08:14 AM, Josef Bacik wrote: > From: Tejun Heo <tj@kernel.org> > > For backcharging we need to know who the page belongs to when swapping > it out. We don't worry about things that do ->rw_page (zram etc) at the > moment, we're only worried about pages that actually go to a block > device. > > Signed-off-by: Tejun Heo <tj@kernel.org> > Signed-off-by: Josef Bacik <jbacik@fb.com> > Acked-by: Johannes Weiner <hannes@cmpxchg.org> > cked-by: Andrew Morton <akpm@linux-foundation.org> Checked-by: ? :) copy-pasto > --- > block/bio.c | 24 ++++++++++++++++++++++++ > include/linux/bio.h | 7 +++++++ > mm/page_io.c | 1 + > 3 files changed, 32 insertions(+)
On 7/3/18 1:27 PM, Randy Dunlap wrote: > On 07/03/2018 08:14 AM, Josef Bacik wrote: >> From: Tejun Heo <tj@kernel.org> >> >> For backcharging we need to know who the page belongs to when swapping >> it out. We don't worry about things that do ->rw_page (zram etc) at the >> moment, we're only worried about pages that actually go to a block >> device. >> >> Signed-off-by: Tejun Heo <tj@kernel.org> >> Signed-off-by: Josef Bacik <jbacik@fb.com> >> Acked-by: Johannes Weiner <hannes@cmpxchg.org> >> cked-by: Andrew Morton <akpm@linux-foundation.org> > > Checked-by: ? :) > copy-pasto I fixed that one up.
diff --git a/block/bio.c b/block/bio.c index c9072a54395e..e09f3626ab5b 100644 --- a/block/bio.c +++ b/block/bio.c @@ -2015,6 +2015,30 @@ EXPORT_SYMBOL(bioset_init_from_src); #ifdef CONFIG_BLK_CGROUP +#ifdef CONFIG_MEMCG +/** + * bio_associate_blkcg_from_page - associate a bio with the page's blkcg + * @bio: target bio + * @page: the page to lookup the blkcg from + * + * Associate @bio with the blkcg from @page's owning memcg. This works like + * every other associate function wrt references. + */ +int bio_associate_blkcg_from_page(struct bio *bio, struct page *page) +{ + struct cgroup_subsys_state *blkcg_css; + + if (unlikely(bio->bi_css)) + return -EBUSY; + if (!page->mem_cgroup) + return 0; + blkcg_css = cgroup_get_e_css(page->mem_cgroup->css.cgroup, + &io_cgrp_subsys); + bio->bi_css = blkcg_css; + return 0; +} +#endif /* CONFIG_MEMCG */ + /** * bio_associate_blkcg - associate a bio with the specified blkcg * @bio: target bio diff --git a/include/linux/bio.h b/include/linux/bio.h index a279ba384da9..a00dfff51aa5 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -553,6 +553,13 @@ do { \ #define bio_dev(bio) \ disk_devt((bio)->bi_disk) +#if defined(CONFIG_MEMCG) && defined(CONFIG_BLK_CGROUP) +int bio_associate_blkcg_from_page(struct bio *bio, struct page *page); +#else +static inline int bio_associate_blkcg_from_page(struct bio *bio, + struct page *page) { return 0; } +#endif + #ifdef CONFIG_BLK_CGROUP int bio_associate_blkcg(struct bio *bio, struct cgroup_subsys_state *blkcg_css); int bio_associate_blkg(struct bio *bio, struct blkcg_gq *blkg); diff --git a/mm/page_io.c b/mm/page_io.c index a552cb37e220..aafd19ec1db4 100644 --- a/mm/page_io.c +++ b/mm/page_io.c @@ -339,6 +339,7 @@ int __swap_writepage(struct page *page, struct writeback_control *wbc, goto out; } bio->bi_opf = REQ_OP_WRITE | REQ_SWAP | wbc_to_write_flags(wbc); + bio_associate_blkcg_from_page(bio, page); count_swpout_vm_event(page); set_page_writeback(page); unlock_page(page);