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AJvYcCVweRXm90UYO2bC60RQqjdEK322grxVqbDBlMHcAnZFruEn6djXh98qucLOoPF2cvyyNF1Y815X2pTwblHu6/Jt@lists.infradead.org X-Gm-Message-State: AOJu0YwtC+L5oXnysERR0JsH11LZz23+4Xvsr6lhJ2qJAPWeoknayRn4 FIMX/wgIzUppmXxf0uXI05kPz0DfLCEviMHTs+gwgGALRhO97ajzW8Aysa3zdN7OCJY+h21RKxh 5ew== X-Google-Smtp-Source: AGHT+IHU4ej+9xtm5sDkWeeRPmRGXEXSjICfBn2mdGglMLGC+glAIOtURcbT/pNs0Pm5Q7kEH8DQAnKQF70= X-Received: from pjbqb11.prod.google.com ([2002:a17:90b:280b:b0:2fe:d556:ec6e]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a17:90b:1344:b0:2ff:6788:cc67 with SMTP id 98e67ed59e1d1-3056096950cmr5544504a91.34.1743540421162; Tue, 01 Apr 2025 13:47:01 -0700 (PDT) Date: Tue, 1 Apr 2025 13:44:20 -0700 In-Reply-To: <20250401204425.904001-1-seanjc@google.com> Mime-Version: 1.0 References: <20250401204425.904001-1-seanjc@google.com> X-Mailer: git-send-email 2.49.0.504.g3bcea36a83-goog Message-ID: <20250401204425.904001-9-seanjc@google.com> Subject: [PATCH 08/12] sched/wait: Drop WQ_FLAG_EXCLUSIVE from add_wait_queue_priority() From: Sean Christopherson To: Paolo Bonzini , Ingo Molnar , Peter Zijlstra , Juri Lelli , Vincent Guittot , Marc Zyngier , Oliver Upton , Sean Christopherson , Paul Walmsley , Palmer Dabbelt , Albert Ou Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-riscv@lists.infradead.org, David Matlack , Juergen Gross , Stefano Stabellini , Oleksandr Tyshchenko X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250401_134702_096318_B3F93EFE X-CRM114-Status: GOOD ( 14.80 ) 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: , Reply-To: Sean Christopherson Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Drop the setting of WQ_FLAG_EXCLUSIVE from add_wait_queue_priority() to differentiate it from add_wait_queue_priority_exclusive(). The one and only user add_wait_queue_priority(), Xen privcmd's irqfd_wakeup(), unconditionally returns '0', i.e. doesn't actually operate in exclusive mode. Cc: Juergen Gross Cc: Stefano Stabellini Cc: Oleksandr Tyshchenko Signed-off-by: Sean Christopherson --- kernel/sched/wait.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/sched/wait.c b/kernel/sched/wait.c index 80d90d1dc24d..2af0fc92e5d3 100644 --- a/kernel/sched/wait.c +++ b/kernel/sched/wait.c @@ -40,7 +40,7 @@ void add_wait_queue_priority(struct wait_queue_head *wq_head, struct wait_queue_ { unsigned long flags; - wq_entry->flags |= WQ_FLAG_EXCLUSIVE | WQ_FLAG_PRIORITY; + wq_entry->flags |= WQ_FLAG_PRIORITY; spin_lock_irqsave(&wq_head->lock, flags); __add_wait_queue(wq_head, wq_entry); spin_unlock_irqrestore(&wq_head->lock, flags); @@ -84,7 +84,7 @@ EXPORT_SYMBOL(remove_wait_queue); * the non-exclusive tasks. Normally, exclusive tasks will be at the end of * the list and any non-exclusive tasks will be woken first. A priority task * may be at the head of the list, and can consume the event without any other - * tasks being woken. + * tasks being woken if it's also an exclusive task. * * There are circumstances in which we can try to wake a task which has already * started to run but is not in state TASK_RUNNING. try_to_wake_up() returns