Commit 930d2b32 authored by Steven Rostedt's avatar Steven Rostedt Committed by Steven Rostedt (Google)
Browse files

tracing: Switch trace_osnoise.c code over to use guard() and __free() 

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.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/20241225222931.517329690@goodmis.org


Signed-off-by: default avatarSteven Rostedt (Google) <rostedt@goodmis.org>
parent a2e27e1b

kernel/trace/trace_osnoise.c

+13 −27
Original line number Diff line number Diff line
@@ -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;

}