From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Morton Subject: + mm-charge-active-memcg-when-no-mm-is-set.patch added to -mm tree Date: Mon, 24 Feb 2020 14:55:43 -0800 Message-ID: <20200224225543.ijEqT1MI6%akpm@linux-foundation.org> References: <20200203173311.6269a8be06a05e5a4aa08a93@linux-foundation.org> Reply-To: linux-kernel@vger.kernel.org Return-path: Received: from mail.kernel.org ([198.145.29.99]:46080 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726651AbgBXWzp (ORCPT ); Mon, 24 Feb 2020 17:55:45 -0500 In-Reply-To: <20200203173311.6269a8be06a05e5a4aa08a93@linux-foundation.org> Sender: mm-commits-owner@vger.kernel.org List-Id: mm-commits@vger.kernel.org To: axboe@kernel.dk, chris@chrisdown.name, guro@fb.com, hannes@cmpxchg.org, hughd@google.com, lizefan@huawei.com, mhocko@kernel.org, mm-commits@vger.kernel.org, schatzberg.dan@gmail.com, shakeelb@google.com, tglx@linutronix.de, tj@kernel.org, vdavydov.dev@gmail.com, yang.shi@linux.alibaba.com The patch titled Subject: mm: charge active memcg when no mm is set has been added to the -mm tree. Its filename is mm-charge-active-memcg-when-no-mm-is-set.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/mm-charge-active-memcg-when-no-mm-is-set.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/mm-charge-active-memcg-when-no-mm-is-set.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Dan Schatzberg Subject: mm: charge active memcg when no mm is set memalloc_use_memcg() worked for kernel allocations but was silently ignored for user pages. 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. Previously, if a NULL mm was passed to mem_cgroup_try_charge (case 3) it 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). Link: http://lkml.kernel.org/r/4456276af198412b2d41cd09d246cd20e0c6d22a.1582581887.git.schatzberg.dan@gmail.com Signed-off-by: Dan Schatzberg Acked-by: Johannes Weiner Acked-by: Tejun Heo Acked-by: Chris Down Reviewed-by: Shakeel Butt Acked-by: Hugh Dickins Cc: Jens Axboe Cc: Li Zefan Cc: Michal Hocko Cc: Roman Gushchin Cc: Thomas Gleixner Cc: Vladimir Davydov Cc: Yang Shi Signed-off-by: Andrew Morton --- mm/memcontrol.c | 11 ++++++++--- mm/shmem.c | 4 ++-- 2 files changed, 10 insertions(+), 5 deletions(-) --- a/mm/memcontrol.c~mm-charge-active-memcg-when-no-mm-is-set +++ a/mm/memcontrol.c @@ -6320,7 +6320,8 @@ exit: * @compound: charge the page as compound or small page * * 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, with *@memcgp pointing to the charged memcg. * Otherwise, an error code is returned. @@ -6364,8 +6365,12 @@ int mem_cgroup_try_charge(struct page *p } } - if (!memcg) - memcg = get_mem_cgroup_from_mm(mm); + if (!memcg) { + if (!mm) + memcg = get_mem_cgroup_from_current(); + else + memcg = get_mem_cgroup_from_mm(mm); + } ret = try_charge(memcg, gfp_mask, nr_pages); --- a/mm/shmem.c~mm-charge-active-memcg-when-no-mm-is-set +++ a/mm/shmem.c @@ -1631,7 +1631,7 @@ static int shmem_swapin_page(struct inod { 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 mem_cgroup *memcg; struct page *page; swp_entry_t swap; @@ -1766,7 +1766,7 @@ repeat: } sbinfo = SHMEM_SB(inode->i_sb); - charge_mm = vma ? vma->vm_mm : current->mm; + charge_mm = vma ? vma->vm_mm : NULL; page = find_lock_entry(mapping, index); if (xa_is_value(page)) { _ Patches currently in -mm which might be from schatzberg.dan@gmail.com are loop-use-worker-per-cgroup-instead-of-kworker.patch mm-charge-active-memcg-when-no-mm-is-set.patch loop-charge-i-o-to-mem-and-blk-cg.patch