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Wong" Subject: Re: [PATCH 2/3] mm: introduce PF_MEMALLOC_NORECLAIM, PF_MEMALLOC_NOWARN Message-ID: References: <20240206215016.961253-1-kent.overstreet@linux.dev> <20240206215016.961253-3-kent.overstreet@linux.dev> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Queue-Id: 2E8404000E X-Rspam-User: X-Rspamd-Server: rspam04 X-Stat-Signature: haqig5tzjnfdmyaw7metay7bdnz54nmj X-HE-Tag: 1707291849-378496 X-HE-Meta: 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 yt886DdP TfYE5fr1IRgJB/CNrLjnm/x/ut4DPnwU0P7NKBHQOhJoyCaLUsT3QB0lZKtHxTulnL04pqekhyt9qEAV6q828zAYP/DSqPrOHmYvR2ZSJRLHcqzdoMVdUPrL9YQ4acL1SXs6oMMW1oBE3aUhnp+c9x6x9f3i7Wev4H+WCtOnd9fRERGI7PI34k1filUjYiOTSPZTMSIop1d3n4fSVsY/1b1skFhMxVs8YE5Ytsa673acMwDe5Obi6FRCU/v+15rLbkdzPGz2br7EoC4ZI5d9Cp+DgwpHWUXqrzcnW1xgKKVoWJhQ41vCSNkdxM/m5oOLsrFtZ+R8bQzgUiPFCg3/UT+IPBNa6H+e/87ABn5qYr6rH973k1cK5N5lhVw== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000065, 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 07-02-24 08:24:33, Vlastimil Babka wrote: > On 2/6/24 22:50, Kent Overstreet wrote: > > Introduce PF_MEMALLOC_* equivalents of some GFP_ flags: > > > > PF_MEMALLOC_NORECLAIM -> GFP_NOWAIT > > In an ideal world, this would be nice, but we are in a world with implicit > "too small to fail" guarantees that has so far been impossible to get away > from [1] for small order GFP_KERNEL allocations, and this scoping would be > only safe if no allocations underneath relied on this behavior. But how to > ensure that's the case? Right http://lkml.kernel.org/r/Zbu_yyChbCO6b2Lj@tiehlicka > [1] https://lwn.net/Articles/723317/ -- Michal Hocko SUSE Labs