From patchwork Wed Dec 25 22:25:41 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steven Rostedt X-Patchwork-Id: 13920878 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 0F8C61509A0; Wed, 25 Dec 2024 22:28:34 +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=1735165715; cv=none; b=owO3jAP8/VCtgq/g908PndUKyxY6YpEb9mQSk032vSxsov9wCv+beTVbvood6+KH/3Z4CiqKk6xIqmg8Fg6sUEB0xOfZ8CBkNRKLCwDAYrwchh7bN0/63vHrXfFwwHJGmKslaXF57asiBertmdkCddg82JOSZqgy67/YDlAfEN4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1735165715; c=relaxed/simple; bh=Vp0vw3+uS0pmRp3t6ZMRayMXF07XyawfMXjfAmU+fcM=; h=Message-ID:Date:From:To:Cc:Subject:References:MIME-Version: Content-Type; b=kAQbKAU1D8yL4Ge2XP01HZ1RqmfFTKJaroSmieqJuii/hDylSI03eb87hudOSbQP40XH7iefDf2vzkpPnONEXVlhrZeJaLde1QD7bgAUyOMq0YCZhPVzan05XCO+Fq4XlC6rwuK8z6ejbi5Vozvi2+tKusQdXEU0ugL6cx/PDLA= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 91D49C4CED6; Wed, 25 Dec 2024 22:28:34 +0000 (UTC) Received: from rostedt by gandalf with local (Exim 4.98) (envelope-from ) id 1tQZsh-0000000FS2b-2n0n; Wed, 25 Dec 2024 17:29:31 -0500 Message-ID: <20241225222931.517329690@goodmis.org> User-Agent: quilt/0.68 Date: Wed, 25 Dec 2024 17:25:41 -0500 From: Steven Rostedt To: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org Cc: Masami Hiramatsu , Mark Rutland , Mathieu Desnoyers , Andrew Morton , Peter Zijlstra Subject: [PATCH v2 1/2] [PATCH] tracing: Switch trace_osnoise.c code over to use guard() and __free() References: <20241225222540.685602520@goodmis.org> Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 The osnoise_hotplug_workfn() grabs two mutexes and cpu_read_lock(). It has various gotos to handle unlocking them. Switch them over to guard() and let the compiler worry about it. The osnoise_cpus_read() has a temporary mask_str allocated and there's some gotos to make sure it gets freed on error paths. Switch that over to __free() to let the compiler worry about it. Signed-off-by: Steven Rostedt (Google) --- Changes since v1: https://lore.kernel.org/20241219201346.533876847@goodmis.org - Fix the goto out error that was fixed in a later patch kernel/trace/trace_osnoise.c | 40 ++++++++++++------------------------ 1 file changed, 13 insertions(+), 27 deletions(-) diff --git a/kernel/trace/trace_osnoise.c b/kernel/trace/trace_osnoise.c index b9f96c77527d..b25c30b05dd0 100644 --- a/kernel/trace/trace_osnoise.c +++ b/kernel/trace/trace_osnoise.c @@ -2083,26 +2083,21 @@ static void osnoise_hotplug_workfn(struct work_struct *dummy) { unsigned int cpu = smp_processor_id(); - mutex_lock(&trace_types_lock); + guard(mutex)(&trace_types_lock); if (!osnoise_has_registered_instances()) - goto out_unlock_trace; + return; - mutex_lock(&interface_lock); - cpus_read_lock(); + guard(mutex)(&interface_lock); + guard(cpus_read_lock)(); if (!cpu_online(cpu)) - goto out_unlock; + return; + if (!cpumask_test_cpu(cpu, &osnoise_cpumask)) - goto out_unlock; + return; start_kthread(cpu); - -out_unlock: - cpus_read_unlock(); - mutex_unlock(&interface_lock); -out_unlock_trace: - mutex_unlock(&trace_types_lock); } static DECLARE_WORK(osnoise_hotplug_work, osnoise_hotplug_workfn); @@ -2300,31 +2295,22 @@ static ssize_t osnoise_cpus_read(struct file *filp, char __user *ubuf, size_t count, loff_t *ppos) { - char *mask_str; + char *mask_str __free(kfree) = NULL; int len; - mutex_lock(&interface_lock); + guard(mutex)(&interface_lock); len = snprintf(NULL, 0, "%*pbl\n", cpumask_pr_args(&osnoise_cpumask)) + 1; mask_str = kmalloc(len, GFP_KERNEL); - if (!mask_str) { - count = -ENOMEM; - goto out_unlock; - } + if (!mask_str) + return -ENOMEM; len = snprintf(mask_str, len, "%*pbl\n", cpumask_pr_args(&osnoise_cpumask)); - if (len >= count) { - count = -EINVAL; - goto out_free; - } + if (len >= count) + return -EINVAL; count = simple_read_from_buffer(ubuf, count, ppos, mask_str, len); -out_free: - kfree(mask_str); -out_unlock: - mutex_unlock(&interface_lock); - return count; } From patchwork Wed Dec 25 22:25:42 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steven Rostedt X-Patchwork-Id: 13920877 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 0F87014EC73; Wed, 25 Dec 2024 22:28:34 +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=1735165715; cv=none; b=RGLtUlEPDZLZVYY/QxF99KesIE9n8tesYh0kXCHZHo35NlY4tNtd5ZpAL26Rms36ZYs/pykyE2c+LyhInPkDpcpmJO1FgHAO0X65Qj8UsOGISL4GPwIGRLKeDEqvKhmA1KlCGXL050Vup4L1N2Z0ZE6deWKsS9kgCUah/mlppM8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1735165715; c=relaxed/simple; bh=1oP38WsUfGdzdO3EGNMFrvWyXUISJYNjtJIXYLpH7Yw=; h=Message-ID:Date:From:To:Cc:Subject:References:MIME-Version: Content-Type; b=e52tfwYIFA4Ysngr4DAKxfxKXEx604ZhEbOWJcMph0REYoUJgfEUyajWwCDn+nXFiYoK+quqlW5NeVlGxU6WMwUeiy37bCJU6QnZpkIBD06us5XTrRjXZzBnvzmRP6DHNakYAEyq4gNtp6xEYeVhRGILhZFUmYtEH4liCygkBpY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id AF6C2C4CED7; Wed, 25 Dec 2024 22:28:34 +0000 (UTC) Received: from rostedt by gandalf with local (Exim 4.98) (envelope-from ) id 1tQZsh-0000000FS3G-3UKm; Wed, 25 Dec 2024 17:29:31 -0500 Message-ID: <20241225222931.684913592@goodmis.org> User-Agent: quilt/0.68 Date: Wed, 25 Dec 2024 17:25:42 -0500 From: Steven Rostedt To: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org Cc: Masami Hiramatsu , Mark Rutland , Mathieu Desnoyers , Andrew Morton , Peter Zijlstra Subject: [PATCH v2 2/2] [PATCH] tracing: Switch trace_stack.c code over to use guard() References: <20241225222540.685602520@goodmis.org> Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 The function stack_trace_sysctl() uses a goto on the error path to jump to the mutex_unlock() code. Replace the logic to use guard() and let the compiler worry about it. Signed-off-by: Steven Rostedt (Google) --- Changes since v1: https://lore.kernel.org/20241219201346.698598387@goodmis.org - Removed fix to osnoise tracer that did not belong in this patch kernel/trace/trace_stack.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/kernel/trace/trace_stack.c b/kernel/trace/trace_stack.c index 7f9572a37333..14c6f272c4d8 100644 --- a/kernel/trace/trace_stack.c +++ b/kernel/trace/trace_stack.c @@ -520,20 +520,18 @@ stack_trace_sysctl(const struct ctl_table *table, int write, void *buffer, int was_enabled; int ret; - mutex_lock(&stack_sysctl_mutex); + guard(mutex)(&stack_sysctl_mutex); was_enabled = !!stack_tracer_enabled; ret = proc_dointvec(table, write, buffer, lenp, ppos); if (ret || !write || (was_enabled == !!stack_tracer_enabled)) - goto out; + return ret; if (stack_tracer_enabled) register_ftrace_function(&trace_ops); else unregister_ftrace_function(&trace_ops); - out: - mutex_unlock(&stack_sysctl_mutex); return ret; }