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From: Muchun Song In-Reply-To: <20250227082223.1173847-1-jingxiangzeng.cas@gmail.com> Date: Thu, 27 Feb 2025 20:19:42 +0800 Cc: linux-mm@kvack.org, akpm@linux-foundation.org, hannes@cmpxchg.org, mhocko@kernel.org, roman.gushchin@linux.dev, shakeel.butt@linux.dev, chengming.zhou@linux.dev, kasong@tencent.com, lkp@intel.com Content-Transfer-Encoding: quoted-printable Message-Id: <3FFDDAF8-CB31-4089-B8E7-3CA2EDBFE999@linux.dev> References: <20250227082223.1173847-1-jingxiangzeng.cas@gmail.com> To: Jingxiang Zeng X-Migadu-Flow: FLOW_OUT X-Rspam-User: X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: DBB441A001C X-Stat-Signature: k7mprjo8nuq15qdmrc1q67wjnpjeczdo X-HE-Tag: 1740658827-961742 X-HE-Meta: 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 IoUibJo4 Xj1UBsrlOf4kVhTUypny2v+BBkxnmlNyUyDhrOb0A3rNpLEcneeyhreAUQyOXD5kweSrTglwKaBl5TMwMvIywRnL3ivw9XPoK4A+rtqTpX6bykpDFUenlHIA9FZflCwapgOokY7I99BJuMH26PUFi7id0RZ2f07g2pTelhaCH7is7ZzC2dD+u0xahOr454kfNxxFxW3bwj6RUf0b6ACW7VU0npV69ao+M0JhNtlt4dICjiI2FPxZTQYHDPJF7Gd0IbYwW5j74nI5T/JFfLDc/cQR3rALCIqCCm9hqrJD1B+RJFlH5aX0IA3CGoS2cDyc+U2sdnyGuKPXAIjdbHBrjs37j/4iaC19+sY95cccxyvIjlFtKZUomaSawUUEWmHk/6JILrkfuJC5jzE4dLqDcn51bjcY81sPnC7eF 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: List-Subscribe: List-Unsubscribe: > On Feb 27, 2025, at 16:22, Jingxiang Zeng = wrote: >=20 > From: Zeng Jingxiang >=20 > In the following memcg_list_lru_alloc() function, mlru here is almost > always NULL, so in most cases this should save a function call, mark > mlru as unlikely to optimize the code, and reusing the mlru for the > next attempt when the tree insertion fails. > do { > xas_lock_irqsave(&xas, flags); > if (!xas_load(&xas) && !css_is_dying(&pos->css)) { > xas_store(&xas, mlru); > if (!xas_error(&xas)) > mlru =3D NULL; > } > xas_unlock_irqrestore(&xas, flags); > } while (xas_nomem(&xas, GFP_KERNEL)); >> if (mlru) > kfree(mlru); >=20 > Reported-by: kernel test robot > Closes: = https://lore.kernel.org/oe-kbuild-all/202412290924.UTP7GH2Z-lkp@intel.com/= > Signed-off-by: Zeng Jingxiang > Suggested-by: Johannes Weiner Reviewed-by: Muchun Song Thanks.