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Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.8.1 MIME-Version: 1.0 In-Reply-To: <20220510030014.3842475-2-surenb@google.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Stat-Signature: 54uuqtp4c6dwr8xquse6ak53ucnf1moo X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: 630DF14009B X-Rspam-User: Authentication-Results: imf23.hostedemail.com; dkim=pass header.d=linuxfoundation.org header.s=google header.b=ca3YiJYk; dmarc=pass (policy=none) header.from=linuxfoundation.org; spf=pass (imf23.hostedemail.com: domain of skhan@linuxfoundation.org designates 209.85.166.50 as permitted sender) smtp.mailfrom=skhan@linuxfoundation.org X-HE-Tag: 1652197554-649787 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 5/9/22 9:00 PM, Suren Baghdasaryan wrote: > With the oom-killer being able to operate on locked pages, exit_mmap > does not need to ensure that oom_reap_task_mm is done before it can > proceed. Instead it can rely on mmap_lock write lock to prevent > oom-killer from operating on the vma tree while it's freeing page > tables. exit_mmap can hold mmap_lock read lock when unmapping vmas > and then take mmap_lock write lock before freeing page tables. > > Signed-off-by: Suren Baghdasaryan > --- > include/linux/oom.h | 2 -- > mm/mmap.c | 25 ++++++------------------- > mm/oom_kill.c | 2 +- > 3 files changed, 7 insertions(+), 22 deletions(-) > How does this improve the test? Include the information on why this change is needed as opposed describing what this does? thanks, -- Shuah