From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Morton Subject: Re: [PATCH v8 0/2] Directed kmem charging Date: Wed, 15 Aug 2018 15:25:11 -0700 Message-ID: <20180815152511.3ea63aa54c5fac0bfe9370da@linux-foundation.org> References: <20180627191250.209150-1-shakeelb@google.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20180627191250.209150-1-shakeelb@google.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: Content-Type: text/plain; charset="us-ascii" To: Shakeel Butt Cc: Michal Hocko , Johannes Weiner , Vladimir Davydov , Jan Kara , Greg Thelen , Amir Goldstein , Roman Gushchin , Alexander Viro , linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org On Wed, 27 Jun 2018 12:12:48 -0700 Shakeel Butt wrote: > The Linux kernel's memory cgroup allows limiting the memory usage of > the jobs running on the system to provide isolation between the jobs. > All the kernel memory allocated in the context of the job and marked > with __GFP_ACCOUNT will also be included in the memory usage and be > limited by the job's limit. > > The kernel memory can only be charged to the memcg of the process in > whose context kernel memory was allocated. However there are cases where > the allocated kernel memory should be charged to the memcg different > from the current processes's memcg. This patch series contains two such > concrete use-cases i.e. fsnotify and buffer_head. > > The fsnotify event objects can consume a lot of system memory for large > or unlimited queues if there is either no or slow listener. The events > are allocated in the context of the event producer. However they should > be charged to the event consumer. Similarly the buffer_head objects can > be allocated in a memcg different from the memcg of the page for which > buffer_head objects are being allocated. > > To solve this issue, this patch series introduces mechanism to charge > kernel memory to a given memcg. In case of fsnotify events, the memcg of > the consumer can be used for charging and for buffer_head, the memcg of > the page can be charged. For directed charging, the caller can use the > scope API memalloc_[un]use_memcg() to specify the memcg to charge for > all the __GFP_ACCOUNT allocations within the scope. This patchset is not showing signs of having been well reviewed at this time. Could people please take another look?