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Biederman" , Jann Horn , Kees Cook , Linus Torvalds , Oleg Nesterov References: <72fdcd154bec7e0dfad090f1af65ddac1e767451.1613392826.git.gladkov.alexey@gmail.com> <72214339-57fc-e47f-bb57-d1b39c69e38e@kernel.dk> <20210222101141.uve6hnftsakf4u7n@example.org> From: Jens Axboe Message-ID: <73b37a89-79d2-9c04-0626-2b164e91c3a8@kernel.dk> Date: Mon, 22 Feb 2021 07:09:41 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20210222101141.uve6hnftsakf4u7n@example.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Stat-Signature: rhxnfecc146ohpxf6xmyd1663qib3s3x X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 1A7B8C00043E Received-SPF: none (kernel.dk>: No applicable sender policy available) receiver=imf14; identity=mailfrom; envelope-from=""; helo=mail-il1-f175.google.com; client-ip=209.85.166.175 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1614002977-44656 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 2/22/21 3:11 AM, Alexey Gladkov wrote: > On Sun, Feb 21, 2021 at 04:38:10PM -0700, Jens Axboe wrote: >> On 2/15/21 5:41 AM, Alexey Gladkov wrote: >>> diff --git a/fs/io-wq.c b/fs/io-wq.c >>> index a564f36e260c..5b6940c90c61 100644 >>> --- a/fs/io-wq.c >>> +++ b/fs/io-wq.c >>> @@ -1090,10 +1091,7 @@ struct io_wq *io_wq_create(unsigned bounded, struct io_wq_data *data) >>> wqe->node = alloc_node; >>> wqe->acct[IO_WQ_ACCT_BOUND].max_workers = bounded; >>> atomic_set(&wqe->acct[IO_WQ_ACCT_BOUND].nr_running, 0); >>> - if (wq->user) { >>> - wqe->acct[IO_WQ_ACCT_UNBOUND].max_workers = >>> - task_rlimit(current, RLIMIT_NPROC); >>> - } >>> + wqe->acct[IO_WQ_ACCT_UNBOUND].max_workers = task_rlimit(current, RLIMIT_NPROC); >> >> This doesn't look like an equivalent transformation. But that may be >> moot if we merge the io_uring-worker.v3 series, as then you would not >> have to touch io-wq at all. > > In the current code the wq->user is always set to current_user(): > > io_uring_create [1] > `- io_sq_offload_create > `- io_init_wq_offload [2] > `-io_wq_create [3] current vs other wasn't my concern, but we're always setting ->user so the test was pointless. So looks fine to me. -- Jens Axboe