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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 v3 03/25] locking: Allow obtaining result of arch_mcs_spin_lock_contended Date: Mon, 3 Mar 2025 07:22:43 -0800 Message-ID: <20250303152305.3195648-4-memxor@gmail.com> X-Mailer: git-send-email 2.43.5 In-Reply-To: <20250303152305.3195648-1-memxor@gmail.com> References: <20250303152305.3195648-1-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/ZANAwAIAUzgyIZIvxHKAcsmYgBnxcWVvzlsIk8Mh+hFnelZKKgCgtqU9iOBLKbPXk+b Hr7ixKqJAjMEAAEIAB0WIQRLvip+Buz51YI8YRFM4MiGSL8RygUCZ8XFlQAKCRBM4MiGSL8Ryow+EA C1eFvCJZOUlVvCcUeprQTPLwv72Q6ykc0vZYM6C30cB2mh8RDYCi22FekqJDDuIBP3ggLIEkBn++iL HayE8E7tcJD+XUme2bPMlycWLuboqWEkhYbEUmsxEiHDMF0tIGq3CXtTX/EFmdPiqhrfYjK2/U0WMS NOVAt9VBBJ2Gkr/Ahg/bKs76BmL83Wf4QvULiFNYpGucOQLCWNYYcOf3+zvSDaQnE1PLiL4lwcEWgJ BWhLal7zLGBO37rSCp8pXZxAjZbOmlIMd7El/c3QBiJ/AUbfRk2SI2aoPiCG7z+vImKhFG9QUUxpHv FXE64wiHpCMTGwLOtsovyQ7+cDSbyd9myY4DYnoOFearxpOGJS6oDKVpKL+YUs0/lrw0EOGtKl8onS nwiFb0cJg40JCw+qXxsA3WdiI5uIK9cMKMra5mIr7h6U3ffX7Tt02zhl0EZujgfUYOKA9Jtck4Hd1x mkS1YmJ/dZEejK5aHgZ5LEBPw9S9BHwJj17/s5GOZti6Ra8ymdC+LLaxSZUDhaBNfI2G2cQJ70ISBx MVd2vcRakzCnM/Eax/CdmqnGby9zEaPOamB6GxfsXaYvqAw9KSqQjVShNIdzUnP/UWD4l5rcaZ50ZC /DEcBbUVqWlsEJY2xKVzRGMI5YAnPpqIb2pZParSp7t5oTMcgQWd2IuyPnAA== 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