On 10/23/21 04:23, Steven Rostedt wrote: > On Thu, 21 Oct 2021 14:56:39 +0200 > Daniel Bristot de Oliveira <bristot@xxxxxxxxxx> wrote: > >> In preparation to support multiple instances, decople the > > "decouple" > >> osnoise/timelat workload from instance specific tracing_cpumask. >> >> Different instances can have conflicing cpumasks, making osnoise > > "conflicting" > > May I suggest a spell check for your commit logs? ;-) Ooops, I will fix them. I use Grammarly on most of my texts, but sometimes I forget to re-check. >> workload management needlessly complex. Osnoise already have its >> global cpu mask. >> >> 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. >> >> Cc: Steven Rostedt <rostedt@xxxxxxxxxxx> >> Cc: Ingo Molnar <mingo@xxxxxxxxxx> >> Cc: Tom Zanussi <zanussi@xxxxxxxxxx> >> Cc: Masami Hiramatsu <mhiramat@xxxxxxxxxx> >> Cc: Juri Lelli <juri.lelli@xxxxxxxxxx> >> Cc: Clark Williams <williams@xxxxxxxxxx> >> Cc: John Kacur <jkacur@xxxxxxxxxx> >> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> >> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> >> Cc: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> >> Cc: Daniel Bristot de Oliveira <bristot@xxxxxxxxxx> >> Cc: linux-rt-users@xxxxxxxxxxxxxxx >> Cc: linux-trace-devel@xxxxxxxxxxxxxxx >> Cc: linux-kernel@xxxxxxxxxxxxxxx >> Signed-off-by: Daniel Bristot de Oliveira <bristot@xxxxxxxxxx> >> --- >> kernel/trace/trace_osnoise.c | 25 +++++++------------------ >> 1 file changed, 7 insertions(+), 18 deletions(-) >> >> diff --git a/kernel/trace/trace_osnoise.c b/kernel/trace/trace_osnoise.c >> index ce053619f289..7b1f8187764c 100644 >> --- a/kernel/trace/trace_osnoise.c >> +++ b/kernel/trace/trace_osnoise.c >> @@ -1553,13 +1553,10 @@ static int start_per_cpu_kthreads(struct trace_array *tr) >> >> cpus_read_lock(); >> /* >> - * Run only on CPUs in which trace and osnoise are allowed to run. >> + * Run only on online CPUs in which trace and osnoise are allowed to > > which trace and osnise? I thought we were removing "trace"? You are correct, I will remove the trace from the comment. Thanks! -- Daniel > -- Steve > >> + * 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; >> @@ -1580,10 +1577,8 @@ 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) >> @@ -1595,9 +1590,6 @@ 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: >> @@ -1700,13 +1692,10 @@ 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, >