From: Daniel Bristot de Oliveira bristot@kernel.org
mainline inclusion from mainline-v5.16-rc1 commit 66df27f19f7dacae471f7214df5bab93d6f88b5f category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I4G64B CVE: NA
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In preparation to support multiple instances, decouple the osnoise/timelat workload from instance-specific tracing_cpumask.
Different instances can have conflicting cpumasks, making osnoise workload management needlessly complex. Osnoise already has its global cpumask.
I also thought about using the first instance mask, but the "first" instance could be removed before the others.
This also fixes the problem that changing the tracing_mask was not re-starting the trace.
Link: https://lkml.kernel.org/r/169a71bcc919ce3ab53ae6f9ca5cde57fffaf9c6.163570289...
Cc: Ingo Molnar mingo@redhat.com Cc: Tom Zanussi zanussi@kernel.org Cc: Masami Hiramatsu mhiramat@kernel.org Cc: Juri Lelli juri.lelli@redhat.com Cc: Clark Williams williams@redhat.com Cc: John Kacur jkacur@redhat.com Cc: Peter Zijlstra peterz@infradead.org Cc: Thomas Gleixner tglx@linutronix.de Cc: Sebastian Andrzej Siewior bigeasy@linutronix.de Cc: Daniel Bristot de Oliveira bristot@kernel.org Cc: linux-rt-users@vger.kernel.org Cc: linux-trace-devel@vger.kernel.org Signed-off-by: Daniel Bristot de Oliveira bristot@kernel.org Signed-off-by: Steven Rostedt (VMware) rostedt@goodmis.org Signed-off-by: Wang ShaoBo bobo.shaobowang@huawei.com Acked-by: Xie XiuQi xiexiuqi@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com --- kernel/trace/trace_osnoise.c | 24 ++++++------------------ 1 file changed, 6 insertions(+), 18 deletions(-)
diff --git a/kernel/trace/trace_osnoise.c b/kernel/trace/trace_osnoise.c index 66b2ed45be3c..b3f1c09870ca 100644 --- a/kernel/trace/trace_osnoise.c +++ b/kernel/trace/trace_osnoise.c @@ -1531,13 +1531,9 @@ static int start_per_cpu_kthreads(struct trace_array *tr)
get_online_cpus(); /* - * Run only on CPUs in which trace and osnoise are allowed to run. + * Run only on online CPUs in which osnoise is allowed to run. */ - cpumask_and(current_mask, tr->tracing_cpumask, &osnoise_cpumask); - /* - * And the CPU is online. - */ - cpumask_and(current_mask, cpu_online_mask, current_mask); + cpumask_and(current_mask, cpu_online_mask, &osnoise_cpumask);
for_each_possible_cpu(cpu) per_cpu(per_cpu_osnoise_var, cpu).kthread = NULL; @@ -1558,10 +1554,8 @@ static int start_per_cpu_kthreads(struct trace_array *tr) #ifdef CONFIG_HOTPLUG_CPU static void osnoise_hotplug_workfn(struct work_struct *dummy) { - struct trace_array *tr = osnoise_trace; unsigned int cpu = smp_processor_id();
- mutex_lock(&trace_types_lock);
if (!osnoise_busy) @@ -1573,9 +1567,6 @@ static void osnoise_hotplug_workfn(struct work_struct *dummy) if (!cpumask_test_cpu(cpu, &osnoise_cpumask)) goto out_unlock;
- if (!cpumask_test_cpu(cpu, tr->tracing_cpumask)) - goto out_unlock; - start_kthread(cpu);
out_unlock: @@ -1678,13 +1669,10 @@ static void osnoise_tracer_stop(struct trace_array *tr); * interface to the osnoise trace. By default, it lists all CPUs, * in this way, allowing osnoise threads to run on any online CPU * of the system. It serves to restrict the execution of osnoise to the - * set of CPUs writing via this interface. Note that osnoise also - * respects the "tracing_cpumask." Hence, osnoise threads will run only - * on the set of CPUs allowed here AND on "tracing_cpumask." Why not - * have just "tracing_cpumask?" Because the user might be interested - * in tracing what is running on other CPUs. For instance, one might - * run osnoise in one HT CPU while observing what is running on the - * sibling HT CPU. + * set of CPUs writing via this interface. Why not use "tracing_cpumask"? + * Because the user might be interested in tracing what is running on + * other CPUs. For instance, one might run osnoise in one HT CPU + * while observing what is running on the sibling HT CPU. */ static ssize_t osnoise_cpus_write(struct file *filp, const char __user *ubuf, size_t count,