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McKenney" , Tejun Heo , Josh Don , Dohyun Kim , linux-arm-kernel@lists.infradead.org, kernel-team@meta.com Subject: [PATCH bpf-next v2 03/26] locking: Allow obtaining result of arch_mcs_spin_lock_contended Date: Thu, 6 Feb 2025 02:54:11 -0800 Message-ID: <20250206105435.2159977-4-memxor@gmail.com> X-Mailer: git-send-email 2.43.5 In-Reply-To: <20250206105435.2159977-1-memxor@gmail.com> References: <20250206105435.2159977-1-memxor@gmail.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=1052; h=from:subject; bh=WHhXMqIdalfkSexlY5e1BRqspbIYdrDmDQT3rX3AKP8=; b=owEBbQKS/ZANAwAIAUzgyIZIvxHKAcsmYgBnpJRkvzlsIk8Mh+hFnelZKKgCgtqU9iOBLKbPXk+b Hr7ixKqJAjMEAAEIAB0WIQRLvip+Buz51YI8YRFM4MiGSL8RygUCZ6SUZAAKCRBM4MiGSL8RypWCD/ 9a6wXeJpwHCx6Ry/+60+90gq49Vx2iM0Ni2K5/JZ/w1SQ1K45M6aFIB7872eGf0XNmEL8eeYRcg6ky oIbxfK6Dz0h4c4cjezC6IO7ADwiRf1nt9gfi3HEwqdWIzBMac9NGH1ITZzTSB9FZuAkqXAfpZZq0iW l9L7JT2bKDalL+4TjYIHnpQaWg+MzdyiUwK9daJqckornGM5bI4UFqkTtWU74gzcj9I8Ww9UAJmZll /0oSi0NI558EvQj/JozkqtizlLGWLPs8WdwyXca/O84yRKYAhzPQZ+Ebe9SP1IcoorQstTzGtBQLkN zeZqTP0CpGFfPZy9B3ND9iBY7eJQQxB2h2yT74z85HkKKEjc2v0asUqBT4vT+B5nCPzdr638w7FtGe emuAf5iymDVjVyVtnlOV9UV5465nfpUZv9DqAwksMUOVSc3qvTgbKcDN4XsiSIJPYVu+XDqiFZqx3Y WlVVJyTFe+L+QnTVi8xn2N/fICy+rFILllPSBpOso5O/9KXfpcu9vnaCtViVPakzRGJqLFeOjxAQNd hQxMdvz26zEoWX77OknnGmg7FcT6xSJ9eFK4uTMlDQbiikiPsGIMVPxVutFarPkQs5maZ7giuy1hnE iy/9siJLZmE3DRYLv0bOoj+wxlb6+yk1cnr9VBCzo9XnhvUEn57+U1QY9opw== X-Developer-Key: i=memxor@gmail.com; a=openpgp; fpr=4BBE2A7E06ECF9D5823C61114CE0C88648BF11CA X-Patchwork-Delegate: bpf@iogearbox.net 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