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[209.85.208.51]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-a868f47c68bsm22626466b.155.2024.08.21.15.59.24 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 21 Aug 2024 15:59:24 -0700 (PDT) Received: by mail-ed1-f51.google.com with SMTP id 4fb4d7f45d1cf-5bed68129a7so319306a12.2 for ; Wed, 21 Aug 2024 15:59:24 -0700 (PDT) X-Forwarded-Encrypted: i=1; AJvYcCXeF73WcD3J5PhfJsDR66p+c8KNAqKKk1BJ3McwE/GkXNXZ+8mP9E7u3Zhwp/sFEc+zRW0QRCgNEQ==@kvack.org X-Received: by 2002:a05:6402:1ec9:b0:5bf:2569:f8eb with SMTP id 4fb4d7f45d1cf-5bf2569fb8fmr1340682a12.36.1724281164316; Wed, 21 Aug 2024 15:59:24 -0700 (PDT) MIME-Version: 1.0 References: <20240817062449.21164-1-21cnbao@gmail.com> <7050deab-e99c-4c83-b7b9-b5dad42f4e95@redhat.com> In-Reply-To: From: Linus Torvalds Date: Thu, 22 Aug 2024 06:59:08 +0800 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v3 0/4] mm: clarify nofail memory allocation To: Yafang Shao Cc: David Hildenbrand , Barry Song <21cnbao@gmail.com>, akpm@linux-foundation.org, linux-mm@kvack.org, 42.hyeyoo@gmail.com, cl@linux.com, hailong.liu@oppo.com, hch@infradead.org, iamjoonsoo.kim@lge.com, mhocko@suse.com, penberg@kernel.org, rientjes@google.com, roman.gushchin@linux.dev, urezki@gmail.com, v-songbaohua@oppo.com, vbabka@suse.cz, virtualization@lists.linux.dev Content-Type: text/plain; charset="UTF-8" X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: D256AA001A X-Stat-Signature: deycyehfiey4m91c87mfmh4qu1c69hza X-Rspam-User: X-HE-Tag: 1724281166-562090 X-HE-Meta: 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 TFJ8l8vd 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.079507, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, 21 Aug 2024 at 20:41, Yafang Shao wrote: > > One potential approach could be to rename GFP_NOFAIL to > GFP_NOFAIL_FOR_SMALL_ALLOC, specifically for smaller allocations, and > to clear this flag for larger allocations. Yes, that sounds like a good way to make sure people don't blame the MM layer when they themselves were the cause of problems. > However, the challenge lies > in determining what constitutes a 'small' allocation. I think we could easily just stick to the historical "order < PAGE_ALLOC_COSTLY_ORDER": * PAGE_ALLOC_COSTLY_ORDER is the order at which allocations are deemed * costly to service. (And the value for that is 3 - orders 0-2 are considered "cheap") Linus