From: Kumar Kartikeya Dwivedi <memxor@gmail.com>
To: bpf@vger.kernel.org, linux-kernel@vger.kernel.org
Cc: Barret Rhoden <brho@google.com>,
Linus Torvalds <torvalds@linux-foundation.org>,
Peter Zijlstra <peterz@infradead.org>,
Will Deacon <will@kernel.org>, Waiman Long <llong@redhat.com>,
Alexei Starovoitov <ast@kernel.org>,
Andrii Nakryiko <andrii@kernel.org>,
Daniel Borkmann <daniel@iogearbox.net>,
Martin KaFai Lau <martin.lau@kernel.org>,
Eduard Zingerman <eddyz87@gmail.com>,
"Paul E. McKenney" <paulmck@kernel.org>,
Tejun Heo <tj@kernel.org>, Josh Don <joshdon@google.com>,
Dohyun Kim <dohyunkim@google.com>,
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 [thread overview]
Message-ID: <20250303152305.3195648-4-memxor@gmail.com> (raw)
In-Reply-To: <20250303152305.3195648-1-memxor@gmail.com>
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 <brho@google.com>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
---
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
--
2.43.5
next prev parent reply other threads:[~2025-03-03 15:23 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-03-03 15:22 [PATCH bpf-next v3 00/25] Resilient Queued Spin Lock Kumar Kartikeya Dwivedi
2025-03-03 15:22 ` [PATCH bpf-next v3 01/25] locking: Move MCS struct definition to public header Kumar Kartikeya Dwivedi
2025-03-03 15:22 ` [PATCH bpf-next v3 02/25] locking: Move common qspinlock helpers to a private header Kumar Kartikeya Dwivedi
2025-03-03 15:22 ` Kumar Kartikeya Dwivedi [this message]
2025-03-03 15:22 ` [PATCH bpf-next v3 04/25] locking: Copy out qspinlock.c to rqspinlock.c Kumar Kartikeya Dwivedi
2025-03-03 15:22 ` [PATCH bpf-next v3 05/25] rqspinlock: Add rqspinlock.h header Kumar Kartikeya Dwivedi
2025-03-03 15:22 ` [PATCH bpf-next v3 06/25] rqspinlock: Drop PV and virtualization support Kumar Kartikeya Dwivedi
2025-03-03 15:22 ` [PATCH bpf-next v3 07/25] rqspinlock: Add support for timeouts Kumar Kartikeya Dwivedi
2025-03-03 15:22 ` [PATCH bpf-next v3 08/25] rqspinlock: Hardcode cond_acquire loops for arm64 Kumar Kartikeya Dwivedi
2025-03-03 15:22 ` [PATCH bpf-next v3 09/25] rqspinlock: Protect pending bit owners from stalls Kumar Kartikeya Dwivedi
2025-03-03 15:22 ` [PATCH bpf-next v3 10/25] rqspinlock: Protect waiters in queue " Kumar Kartikeya Dwivedi
2025-03-03 15:22 ` [PATCH bpf-next v3 11/25] rqspinlock: Protect waiters in trylock fallback " Kumar Kartikeya Dwivedi
2025-03-03 15:22 ` [PATCH bpf-next v3 12/25] rqspinlock: Add deadlock detection and recovery Kumar Kartikeya Dwivedi
2025-03-03 15:22 ` [PATCH bpf-next v3 13/25] rqspinlock: Add a test-and-set fallback Kumar Kartikeya Dwivedi
2025-03-03 15:22 ` [PATCH bpf-next v3 14/25] rqspinlock: Add basic support for CONFIG_PARAVIRT Kumar Kartikeya Dwivedi
2025-03-03 15:22 ` [PATCH bpf-next v3 15/25] rqspinlock: Add helper to print a splat on timeout or deadlock Kumar Kartikeya Dwivedi
2025-03-03 15:22 ` [PATCH bpf-next v3 16/25] rqspinlock: Add macros for rqspinlock usage Kumar Kartikeya Dwivedi
2025-03-03 15:22 ` [PATCH bpf-next v3 17/25] rqspinlock: Add locktorture support Kumar Kartikeya Dwivedi
2025-03-03 15:22 ` [PATCH bpf-next v3 18/25] rqspinlock: Add entry to Makefile, MAINTAINERS Kumar Kartikeya Dwivedi
2025-03-03 15:22 ` [PATCH bpf-next v3 19/25] bpf: Convert hashtab.c to rqspinlock Kumar Kartikeya Dwivedi
2025-03-03 15:23 ` [PATCH bpf-next v3 20/25] bpf: Convert percpu_freelist.c " Kumar Kartikeya Dwivedi
2025-03-03 15:23 ` [PATCH bpf-next v3 21/25] bpf: Convert lpm_trie.c " Kumar Kartikeya Dwivedi
2025-03-03 15:23 ` [PATCH bpf-next v3 22/25] bpf: Introduce rqspinlock kfuncs Kumar Kartikeya Dwivedi
2025-03-03 15:23 ` [PATCH bpf-next v3 23/25] bpf: Implement verifier support for rqspinlock Kumar Kartikeya Dwivedi
2025-03-03 15:23 ` [PATCH bpf-next v3 24/25] bpf: Maintain FIFO property for rqspinlock unlock Kumar Kartikeya Dwivedi
2025-03-03 15:23 ` [PATCH bpf-next v3 25/25] selftests/bpf: Add tests for rqspinlock Kumar Kartikeya Dwivedi
2025-03-14 23:49 ` [PATCH bpf-next v3 00/25] Resilient Queued Spin Lock Kumar Kartikeya Dwivedi
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