Skip to contentSkip to conversation

FAILED: patch "[PATCH] tracing/hwlat: Honor the tracing_cpumask" failed to apply to 4.9-stable tree

PATCH [email protected] 1 participant 1 message Aug 19, 2020

Subsystems (3)
Stable branch Tracing Tracing OS noise / latency tracers
lore
Share & tools
lore

[email protected]

author maintainer
#0 lore raw

The patch below does not apply to the 4.9-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 96b4833b6827a62c295b149213c68b559514c929 Mon Sep 17 00:00:00 2001
From: Kevin Hao <[email protected]>
Date: Thu, 30 Jul 2020 16:23:18 +0800
Subject: [PATCH] tracing/hwlat: Honor the tracing_cpumask

In calculation of the cpu mask for the hwlat kernel thread, the wrong cpu mask is used instead of the tracing_cpumask, this causes the tracing/tracing_cpumask useless for hwlat tracer. Fixes it.

Link https://lkml.kernel.org/r/[email protected] open here
Cc Ingo Molnar <[email protected]>
Cc [email protected]
Fixes 0330f7aa8ee6 ("tracing: Have hwlat trace migrate across tracing_cpumask CPUs")
Signed-off-by Kevin Hao <[email protected]>
Signed-off-by Steven Rostedt (VMware) <[email protected]>
kernel/trace/trace_hwlat.c +3 -2
index ddb528a6cd51..17873e5d0353 100644
@@ -283,6 +283,7 @@ static bool disable_migrate;
 static void move_to_next_cpu(void)
 {
 	struct cpumask *current_mask = &save_cpumask;
+	struct trace_array *tr = hwlat_trace;
 	int next_cpu;
 
 	if (disable_migrate)

@@ -296,7 +297,7 @@ static void move_to_next_cpu(void)
 		goto disable;
 
 	get_online_cpus();
-	cpumask_and(current_mask, cpu_online_mask, tracing_buffer_mask);
+	cpumask_and(current_mask, cpu_online_mask, tr->tracing_cpumask);
 	next_cpu = cpumask_next(smp_processor_id(), current_mask);
 	put_online_cpus();
 

@@ -372,7 +373,7 @@ static int start_kthread(struct trace_array *tr)
 
 	/* Just pick the first CPU on first iteration */
 	get_online_cpus();
-	cpumask_and(current_mask, cpu_online_mask, tracing_buffer_mask);
+	cpumask_and(current_mask, cpu_online_mask, tr->tracing_cpumask);
 	put_online_cpus();
 	next_cpu = cpumask_first(current_mask);