| Message ID | 20210316153655.500806-3-schatzberg.dan@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Charge loop device i/o to issuing cgroup | expand |
On Tue, Mar 16, 2021 at 8:37 AM Dan Schatzberg <schatzberg.dan@gmail.com> wrote: > > memalloc_use_memcg() worked for kernel allocations but was silently > ignored for user pages. set_active_memcg() > > This patch establishes a precedence order for who gets charged: > > 1. If there is a memcg associated with the page already, that memcg is > charged. This happens during swapin. > > 2. If an explicit mm is passed, mm->memcg is charged. This happens > during page faults, which can be triggered in remote VMs (eg gup). > > 3. Otherwise consult the current process context. If it has configured > a current->active_memcg, use that. Otherwise, current->mm->memcg. It's a bit more sophisticated than current->active_memcg. It has been extended to work in interrupt context as well. > > Previously, if a NULL mm was passed to mem_cgroup_try_charge (case 3) it mem_cgroup_charge() > would always charge the root cgroup. Now it looks up the current > active_memcg first (falling back to charging the root cgroup if not > set). > > Signed-off-by: Dan Schatzberg <schatzberg.dan@gmail.com> > Acked-by: Johannes Weiner <hannes@cmpxchg.org> > Acked-by: Tejun Heo <tj@kernel.org> > Acked-by: Chris Down <chris@chrisdown.name> > Reviewed-by: Shakeel Butt <shakeelb@google.com> > --- > mm/filemap.c | 2 +- > mm/memcontrol.c | 14 +++++++++++--- > mm/shmem.c | 4 ++-- > 3 files changed, 14 insertions(+), 6 deletions(-) > > diff --git a/mm/filemap.c b/mm/filemap.c > index 43700480d897..5135f330f05c 100644 > --- a/mm/filemap.c > +++ b/mm/filemap.c > @@ -843,7 +843,7 @@ noinline int __add_to_page_cache_locked(struct page *page, > page->index = offset; > > if (!huge) { > - error = mem_cgroup_charge(page, current->mm, gfp); > + error = mem_cgroup_charge(page, NULL, gfp); > if (error) > goto error; > charged = true; > diff --git a/mm/memcontrol.c b/mm/memcontrol.c > index e064ac0d850a..9a1b23ed3412 100644 > --- a/mm/memcontrol.c > +++ b/mm/memcontrol.c > @@ -6690,7 +6690,8 @@ void mem_cgroup_calculate_protection(struct mem_cgroup *root, > * @gfp_mask: reclaim mode > * > * Try to charge @page to the memcg that @mm belongs to, reclaiming > - * pages according to @gfp_mask if necessary. > + * pages according to @gfp_mask if necessary. if @mm is NULL, try to > + * charge to the active memcg. > * > * Returns 0 on success. Otherwise, an error code is returned. > */ > @@ -6726,8 +6727,15 @@ int mem_cgroup_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask) > rcu_read_unlock(); > } > > - if (!memcg) > - memcg = get_mem_cgroup_from_mm(mm); > + if (!memcg) { > + if (!mm) { > + memcg = get_mem_cgroup_from_current(); > + if (!memcg) > + memcg = get_mem_cgroup_from_mm(current->mm); > + } else { > + memcg = get_mem_cgroup_from_mm(mm); > + } > + } You will need to rebase to the latest mm tree. This code has changed.
On Tue, Mar 16, 2021 at 08:50:16AM -0700, Shakeel Butt wrote:
> You will need to rebase to the latest mm tree. This code has changed.
Thanks for the feedback, I will address these comments in another
rebase. I'll wait and see if there's any comments concerning the
loop-related patches but it sounds like this will need to go through
the mm-tree
diff --git a/mm/filemap.c b/mm/filemap.c index 43700480d897..5135f330f05c 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -843,7 +843,7 @@ noinline int __add_to_page_cache_locked(struct page *page, page->index = offset; if (!huge) { - error = mem_cgroup_charge(page, current->mm, gfp); + error = mem_cgroup_charge(page, NULL, gfp); if (error) goto error; charged = true; diff --git a/mm/memcontrol.c b/mm/memcontrol.c index e064ac0d850a..9a1b23ed3412 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -6690,7 +6690,8 @@ void mem_cgroup_calculate_protection(struct mem_cgroup *root, * @gfp_mask: reclaim mode * * Try to charge @page to the memcg that @mm belongs to, reclaiming - * pages according to @gfp_mask if necessary. + * pages according to @gfp_mask if necessary. if @mm is NULL, try to + * charge to the active memcg. * * Returns 0 on success. Otherwise, an error code is returned. */ @@ -6726,8 +6727,15 @@ int mem_cgroup_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask) rcu_read_unlock(); } - if (!memcg) - memcg = get_mem_cgroup_from_mm(mm); + if (!memcg) { + if (!mm) { + memcg = get_mem_cgroup_from_current(); + if (!memcg) + memcg = get_mem_cgroup_from_mm(current->mm); + } else { + memcg = get_mem_cgroup_from_mm(mm); + } + } ret = try_charge(memcg, gfp_mask, nr_pages); if (ret) diff --git a/mm/shmem.c b/mm/shmem.c index b2db4ed0fbc7..353b362c370e 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -1695,7 +1695,7 @@ static int shmem_swapin_page(struct inode *inode, pgoff_t index, { struct address_space *mapping = inode->i_mapping; struct shmem_inode_info *info = SHMEM_I(inode); - struct mm_struct *charge_mm = vma ? vma->vm_mm : current->mm; + struct mm_struct *charge_mm = vma ? vma->vm_mm : NULL; struct page *page; swp_entry_t swap; int error; @@ -1816,7 +1816,7 @@ static int shmem_getpage_gfp(struct inode *inode, pgoff_t index, } sbinfo = SHMEM_SB(inode->i_sb); - charge_mm = vma ? vma->vm_mm : current->mm; + charge_mm = vma ? vma->vm_mm : NULL; page = pagecache_get_page(mapping, index, FGP_ENTRY | FGP_HEAD | FGP_LOCK, 0);