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McKenney" , Tejun Heo , Josh Don , Dohyun Kim , linux-arm-kernel@lists.infradead.org, kkd@meta.com, kernel-team@meta.com Subject: [PATCH bpf-next v4 03/25] locking: Allow obtaining result of arch_mcs_spin_lock_contended Date: Sat, 15 Mar 2025 21:05:19 -0700 Message-ID: <20250316040541.108729-4-memxor@gmail.com> X-Mailer: git-send-email 2.47.1 In-Reply-To: <20250316040541.108729-1-memxor@gmail.com> References: <20250316040541.108729-1-memxor@gmail.com> MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=1052; h=from:subject; bh=bCYnbE+K73lTBoOLttYSRrRShne2EKo6ypzNdER5dO0=; b=owEBbQKS/ZANAwAIAUzgyIZIvxHKAcsmYgBn1k3bZVJO+UtaXh2ksd2ygsxMkhcgERBwBjs9FllI XcQQD02JAjMEAAEIAB0WIQRLvip+Buz51YI8YRFM4MiGSL8RygUCZ9ZN2wAKCRBM4MiGSL8RyrE+D/ 9mak4NXwqkExtA6v4P4pv81udcNOxwDMXUb35o6/CJjxArzw0HvdY428jcentyE0WrkYShVveSLa8v gbZpOY+R4DxGLAG9A7vhsHWyBPTG4Nm/fz4K6mql1dG8Rn86G+pi7KNm9DUbA8dhS79edorwxQ74w2 ZgfwIKcHyHKk//0Zzo+3TqqGOY647CW2eelFr/fOUbVF3aHHtj3H9SF2Cn5TYkGwX37s0nQT08NeRC 6lC3cRBakQV16GrBRvnzuxwKCr0riv4WOvH+At23JAXrPoKxRRCJyHthJUB5AjLXXVpWjd3vQRZ84e m4j04JXHSKMor4vL6CJNdPbQ45sjOyPq0IX85pP4AbEnoRaoWA17Z6Sc8YfUIE7vO6miyigFrZ/abj THdDEqULYZgI9XRQlWB8yDm/grvuD87SrkKzJWdCqZOqs254FuPsbYcY7KBd395/gAGmRcGdmPdBEn vM+vkNfbds7UMoaPYMZ25ck7vCMuPGGuBlKCj7EkeTPCiIB0tGsLZGXd2YsjABChEPH7pPPLS7CnTm TU+UtlJRzlhncgkJdmlb8xaZyibSXEjKB9b3pd4fVNDotHhyB0wT74fhCqGrDkuRX7vV7yNHq1zr5J hr44cNlreYhdVZJm7c3j0JwwYDA2zXpv5B2N5U9pbKtklVtFtNJa4aT0axtw== X-Developer-Key: i=memxor@gmail.com; a=openpgp; fpr=4BBE2A7E06ECF9D5823C61114CE0C88648BF11CA X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250315_210548_880345_A62195B6 X-CRM114-Status: GOOD ( 11.04 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org To support upcoming changes that require inspecting the return value once the conditional waiting loop in arch_mcs_spin_lock_contended terminates, modify the macro to preserve the result of smp_cond_load_acquire. This enables checking the return value as needed, which will help disambiguate the MCS node’s locked state in future patches. Reviewed-by: Barret Rhoden Signed-off-by: Kumar Kartikeya Dwivedi --- kernel/locking/mcs_spinlock.h | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/kernel/locking/mcs_spinlock.h b/kernel/locking/mcs_spinlock.h index 16160ca8907f..5c92ba199b90 100644 --- a/kernel/locking/mcs_spinlock.h +++ b/kernel/locking/mcs_spinlock.h @@ -24,9 +24,7 @@ * spinning, and smp_cond_load_acquire() provides that behavior. */ #define arch_mcs_spin_lock_contended(l) \ -do { \ - smp_cond_load_acquire(l, VAL); \ -} while (0) + smp_cond_load_acquire(l, VAL) #endif #ifndef arch_mcs_spin_unlock_contended