From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id EDAFD16EB59 for ; Fri, 21 Jun 2024 09:16:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718961374; cv=none; b=m9Pa4C1QN4KRVrbyUFdcITR+xpQTLKO8bKerWSWrj/VIMQev/+R7fNXie3Ywuovj8NbyGVqJuiry0vV0fdD94yp32LIiyr37SSZJxJ7VGyNVEwlNlEyX3zNvoRlQtn7w/sncOEiTews4Z1oK6+tSIwo+9pQV7coSj/Cxygd+eRk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718961374; c=relaxed/simple; bh=yxEHyP8F59DlEgnpBUShwu2ascF0KGLnYNcwxKRX5ns=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=RI1BZ75FxcUfHGNzPLHJNbanlr4gXzj7vsH+Z5jsytEuE4fOqHJyhXB+iWaQajkwD/vzhddTMbyIu0Ahz62A7xA4ln3/RCBI59EwY9JZk/rGhvW57sDyyqbfURDMOtx5gYFZukG2I0MqkRD72UDbh2VkbD+SEhcSh6k7AX8Oo8o= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=PENtdBkZ; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="PENtdBkZ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 277F5C4AF0F; Fri, 21 Jun 2024 09:16:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1718961373; bh=yxEHyP8F59DlEgnpBUShwu2ascF0KGLnYNcwxKRX5ns=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=PENtdBkZXrxpozLB69Dm8bpmeyW0THBFbKA1GfpgYQxjyTf6QCWSySA3zZ93EQQwS cFiyrHFfk+ufP4kOcHDcpjNhB7+ERI9l9YQkDK1Gtr5FWXELeDgXI7RqvMD6iFV/U5 RYgzTbbWBW16DIOpMlnp7MtckBaxNNyTcrB1VsWIGQF5/PBqSY5cBz/g3EXO6KIpy7 0w2ftYSvlP7QYtPktXDWkHakCIdiKqF90uUTN2hAPdsFbdGpi7q76er1AqRf5rvS2k /0PldJoxDmxV91Peezzvq8ezR+01Rss5eRh4NDus01wG4tIGJ5J+2TtlA9G62yG6/S fQ9Ey0e8QSS7Q== From: Frederic Weisbecker To: LKML Cc: Frederic Weisbecker , Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Namhyung Kim , Mark Rutland , Alexander Shishkin , Jiri Olsa , Ian Rogers , Adrian Hunter , Sebastian Andrzej Siewior Subject: [PATCH 2/4] task_work: Introduce task_work_cancel() again Date: Fri, 21 Jun 2024 11:15:59 +0200 Message-ID: <20240621091601.18227-3-frederic@kernel.org> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240621091601.18227-1-frederic@kernel.org> References: <20240621091601.18227-1-frederic@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Re-introduce task_work_cancel(), this time to cancel an actual callback and not *any* callback pointing to a given function. This is going to be needed for perf events event freeing. Signed-off-by: Frederic Weisbecker --- include/linux/task_work.h | 1 + kernel/task_work.c | 24 ++++++++++++++++++++++++ 2 files changed, 25 insertions(+) diff --git a/include/linux/task_work.h b/include/linux/task_work.h index 23ab01ae185e..26b8a47f41fc 100644 --- a/include/linux/task_work.h +++ b/include/linux/task_work.h @@ -31,6 +31,7 @@ int task_work_add(struct task_struct *task, struct callback_head *twork, struct callback_head *task_work_cancel_match(struct task_struct *task, bool (*match)(struct callback_head *, void *data), void *data); struct callback_head *task_work_cancel_func(struct task_struct *, task_work_func_t); +bool task_work_cancel(struct task_struct *task, struct callback_head *cb); void task_work_run(void); static inline void exit_task_work(struct task_struct *task) diff --git a/kernel/task_work.c b/kernel/task_work.c index 54ac24059daa..2134ac8057a9 100644 --- a/kernel/task_work.c +++ b/kernel/task_work.c @@ -136,6 +136,30 @@ task_work_cancel_func(struct task_struct *task, task_work_func_t func) return task_work_cancel_match(task, task_work_func_match, func); } +static bool task_work_match(struct callback_head *cb, void *data) +{ + return cb == data; +} + +/** + * task_work_cancel - cancel a pending work added by task_work_add() + * @task: the task which should execute the work + * @cb: the callback to remove if queued + * + * Remove a callback from a task's queue if queued. + * + * RETURNS: + * True if the callback was queued and got cancelled, false otherwise. + */ +bool task_work_cancel(struct task_struct *task, struct callback_head *cb) +{ + struct callback_head *ret; + + ret = task_work_cancel_match(task, task_work_match, cb); + + return ret == cb; +} + /** * task_work_run - execute the works added by task_work_add() * -- 2.45.2