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[2003:dc:6f1d:f00:230:64ff:fe74:809]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-b01902d0e99sm541005766b.12.2025.09.01.02.19.31 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 01 Sep 2025 02:19:32 -0700 (PDT) From: Max Kellermann To: akpm@linux-foundation.org, david@redhat.com, axelrasmussen@google.com, yuanchu@google.com, willy@infradead.org, hughd@google.com, mhocko@suse.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, lorenzo.stoakes@oracle.com, Liam.Howlett@oracle.com, vbabka@suse.cz, rppt@kernel.org, surenb@google.com, vishal.moola@gmail.com, linux@armlinux.org.uk, James.Bottomley@HansenPartnership.com, deller@gmx.de, agordeev@linux.ibm.com, gerald.schaefer@linux.ibm.com, hca@linux.ibm.com, gor@linux.ibm.com, borntraeger@linux.ibm.com, svens@linux.ibm.com, davem@davemloft.net, andreas@gaisler.com, dave.hansen@linux.intel.com, luto@kernel.org, peterz@infradead.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, x86@kernel.org, hpa@zytor.com, chris@zankel.net, jcmvbkbc@gmail.com, viro@zeniv.linux.org.uk, brauner@kernel.org, jack@suse.cz, weixugc@google.com, baolin.wang@linux.alibaba.com, rientjes@google.com, shakeel.butt@linux.dev, max.kellermann@ionos.com, thuth@redhat.com, broonie@kernel.org, osalvador@suse.de, jfalempe@redhat.com, mpe@ellerman.id.au, nysal@linux.ibm.com, linux-arm-kernel@lists.infradead.org, linux-parisc@vger.kernel.org, linux-s390@vger.kernel.org, sparclinux@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: [PATCH v4 05/12] mm/oom_kill: add const to pointer parameter for improved const-correctness Date: Mon, 1 Sep 2025 11:19:08 +0200 Message-ID: <20250901091916.3002082-6-max.kellermann@ionos.com> X-Mailer: git-send-email 2.47.2 In-Reply-To: <20250901091916.3002082-1-max.kellermann@ionos.com> References: <20250901091916.3002082-1-max.kellermann@ionos.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" The memory management (mm) subsystem is a fundamental low-level component of the Linux kernel. Establishing const-correctness at this foundational level enables higher-level subsystems, such as filesystems and drivers, to also adopt const-correctness in their interfaces. This patch lays the groundwork for broader const-correctness throughout the kernel by starting with the core mm subsystem. This patch adds const qualifiers to task_struct and mm_struct pointer parameters in the OOM killer code that do not modify the referenced memory, improving type safety and enabling compiler optimizations. Functions improved: - process_shares_mm() Signed-off-by: Max Kellermann --- include/linux/mm.h | 2 +- mm/oom_kill.c | 3 ++- 2 files changed, 3 insertions(+), 2 deletions(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index 18deb14cb1f5..f70c6b4d5f80 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -3840,7 +3840,7 @@ static inline int in_gate_area(struct mm_struct *mm, = unsigned long addr) } #endif /* __HAVE_ARCH_GATE_AREA */ =20 -extern bool process_shares_mm(struct task_struct *p, struct mm_struct *mm); +bool process_shares_mm(const struct task_struct *p, const struct mm_struct= *mm); =20 void drop_slab(void); =20 diff --git a/mm/oom_kill.c b/mm/oom_kill.c index 17650f0b516e..2620b32a8eba 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -490,7 +490,8 @@ static bool oom_killer_disabled __read_mostly; * task's threads: if one of those is using this mm then this task was also * using it. */ -bool process_shares_mm(struct task_struct *p, struct mm_struct *mm) +bool process_shares_mm(const struct task_struct *const p, + const struct mm_struct *const mm) { struct task_struct *t; =20 --=20 2.47.2