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charset="UTF-8" ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1657152873; a=rsa-sha256; cv=none; b=AshQmfDdlDvfK+jxyOFukaPOpnmrnXxY9TXJChhM9OgNYQ7Nfmy7lljS6wbyxmnpDi2uVC dtsJs0WBPfDRR22Zd+p8S7fhxiXa9NWR+PIy5zT5BfPAHYC99m0HkfTBfEOPUnHgLAdnN7 DInarggQoHCJN8Pe536jBezOZ0Sg/94= ARC-Authentication-Results: i=1; imf11.hostedemail.com; dkim=pass header.d=gmail.com header.s=20210112 header.b=lYczNUyQ; dmarc=pass (policy=none) header.from=gmail.com; spf=pass (imf11.hostedemail.com: domain of alexei.starovoitov@gmail.com designates 209.85.208.52 as permitted sender) smtp.mailfrom=alexei.starovoitov@gmail.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1657152873; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=RhqfdQ1GQrT/2BgJcOYLTDt5L8saJLJldEnPN/oVRn8=; b=x5dzhiNJz6TBEM7QFpD7zGDAx1UD441/Tqxq1lR7ijChI0clVn9h5E1DmudFxLotNGyIN8 53x7gWcvZVzYsGvRpdwFLRwjI9kekO4y3Mq+3Kqd0DGuwnPhdDBG8ckQz8Clkc4HYnIfsg cY31dwB9PKfjWmlTbaUqcisya6C8M3U= X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: 0607A4002C X-Rspam-User: Authentication-Results: imf11.hostedemail.com; dkim=pass header.d=gmail.com header.s=20210112 header.b=lYczNUyQ; dmarc=pass (policy=none) header.from=gmail.com; spf=pass (imf11.hostedemail.com: domain of alexei.starovoitov@gmail.com designates 209.85.208.52 as permitted sender) smtp.mailfrom=alexei.starovoitov@gmail.com X-Stat-Signature: b78q6gw3c351r3epez1fmjpwh53rjw3h X-HE-Tag: 1657152872-954673 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000012, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, Jul 6, 2022 at 5:07 PM Shakeel Butt wrote: > > On Wed, Jul 06, 2022 at 03:58:47PM +0000, Yafang Shao wrote: > > GFP_ATOMIC doesn't cooperate well with memcg pressure so far, especially > > if we allocate too much GFP_ATOMIC memory. For example, when we set the > > memcg limit to limit a non-preallocated bpf memory, the GFP_ATOMIC can > > easily break the memcg limit by force charge. So it is very dangerous to > > use GFP_ATOMIC in non-preallocated case. One way to make it safe is to > > remove __GFP_HIGH from GFP_ATOMIC, IOW, use (__GFP_ATOMIC | > > __GFP_KSWAPD_RECLAIM) instead, then it will be limited if we allocate > > too much memory. > > Please use GFP_NOWAIT instead of (__GFP_ATOMIC | __GFP_KSWAPD_RECLAIM). > There is already a plan to completely remove __GFP_ATOMIC and mm-tree > already have a patch for that. hmm. ok. reverted.