2017-08-25 05:48:28

by Ziqian SUN (Zamir)

Subject: [PATCH] trace-cmd report: Fix hash.key in option -w

From: "Ziqian SUN (Zamir)" <[email protected]>

In add_wakeup function the hash list is created with hash.key = value.
This makes add_sched function will never find a match with the key which
results in trace-cmd report will never show the average latency with the
following command:
trace-cmd report -w -F 'sched_switch,sched_wakeup'
With this patch, the command will show average latency as it used to be
in v2.4.2 like

Average wakeup latency: 28.460 usecs
Maximum Latency: 669.268 usecs at timestamp: 16337.629767
Minimum Latency: 2.153 usecs at timestamp: 16337.533735

RT task timings:

Average wakeup latency: 23.106 usecs
Maximum Latency: 57.482 usecs at timestamp: 16337.187531
Minimum Latency: 4.127 usecs at timestamp: 16336.945209

Reported-by: Joe Mario <[email protected]>
Signed-off-by: Ziqian SUN (Zamir) <[email protected]>
---
trace-read.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/trace-read.c b/trace-read.c
index ebb2368..350a843 100644
--- a/trace-read.c
+++ b/trace-read.c
@@ -610,7 +610,7 @@ static void add_wakeup(unsigned int val, unsigned long long start)
info = malloc(sizeof(*info));
if (!info)
die("Failed to allocate wakeup info");
- info->hash.key = val;
+ info->hash.key = key;
info->start = start;
trace_hash_add(&wakeup_hash, &info->hash);
}
--
1.8.3.1

2017-08-25 14:22:33

by Steven Rostedt

Subject: Re: [PATCH] trace-cmd report: Fix hash.key in option -w

On Fri, 25 Aug 2017 13:47:49 +0800
"Ziqian SUN (Zamir)" <[email protected]> wrote:

> From: "Ziqian SUN (Zamir)" <[email protected]>
>
> In add_wakeup function the hash list is created with hash.key = value.
> This makes add_sched function will never find a match with the key which
> results in trace-cmd report will never show the average latency with the
> following command:
> trace-cmd report -w -F 'sched_switch,sched_wakeup'
> With this patch, the command will show average latency as it used to be
> in v2.4.2 like
>
> Average wakeup latency: 28.460 usecs
> Maximum Latency: 669.268 usecs at timestamp: 16337.629767
> Minimum Latency: 2.153 usecs at timestamp: 16337.533735
>
> RT task timings:
>
> Average wakeup latency: 23.106 usecs
> Maximum Latency: 57.482 usecs at timestamp: 16337.187531
> Minimum Latency: 4.127 usecs at timestamp: 16336.945209
>
> Reported-by: Joe Mario <[email protected]>
> Signed-off-by: Ziqian SUN (Zamir) <[email protected]>

Thanks a lot Ziqian! Added. Will push out soon.

I need to update the stables too.

-- Steve