Commit ca06d7e1 authored by Tomas Glozar's avatar Tomas Glozar Committed by Wentao Guan
Browse files

rtla/timerlat_top: Set OSNOISE_WORKLOAD for kernel threads 

stable inclusion
from stable-v6.6.81
commit 39854d3821259da7421b19802644053e36f75e90
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/IBX1M5

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=39854d3821259da7421b19802644053e36f75e90

--------------------------------

commit 217f0b1e990e30a1f06f6d531fdb4530f4788d48 upstream.

When using rtla timerlat with userspace threads (-u or -U), rtla
disables the OSNOISE_WORKLOAD option in
/sys/kernel/tracing/osnoise/options. This option is not re-enabled in a
subsequent run with kernel-space threads, leading to rtla collecting no
results if the previous run exited abnormally:

$ rtla timerlat top -u
^\Quit (core dumped)
$ rtla timerlat top -k -d 1s
                                     Timer Latency
  0 00:00:01   |          IRQ Timer Latency (us)        |         Thread Timer Latency (us)
CPU COUNT      |      cur       min       avg       max |      cur       min       avg       max

The issue persists until OSNOISE_WORKLOAD is set manually by running:
$ echo OSNOISE_WORKLOAD > /sys/kernel/tracing/osnoise/options

Set OSNOISE_WORKLOAD when running rtla with kernel-space threads if
available to fix the issue.

Cc: stable@vger.kernel.org
Cc: John Kacur <jkacur@redhat.com>
Cc: Luis Goncalves <lgoncalv@redhat.com>
Link: https://lore.kernel.org/20250107144823.239782-4-tglozar@redhat.com


Fixes: cdca4f4e ("rtla/timerlat_top: Add timerlat user-space support")
Signed-off-by: default avatarTomas Glozar <tglozar@redhat.com>
Signed-off-by: default avatarSteven Rostedt (Google) <rostedt@goodmis.org>
[ params->kernel_workload does not exist in 6.6, use
!params->user_top ]
Signed-off-by: default avatarTomas Glozar <tglozar@redhat.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit 39854d3821259da7421b19802644053e36f75e90)
Signed-off-by: default avatarWentao Guan <guanwentao@uniontech.com>
parent f1b11f1f

tools/tracing/rtla/src/timerlat_top.c

+9 −6
Original line number Diff line number Diff line
@@ -679,13 +679,16 @@ timerlat_top_apply_config(struct osnoise_tool *top, struct timerlat_top_params * 
		auto_house_keeping(&params->monitored_cpus);

	}



	if (params->user_top) {

		retval = osnoise_set_workload(top->context, 0);

		if (retval) {

	/*

	* Set workload according to type of thread if the kernel supports it.

	* On kernels without support, user threads will have already failed

	* on missing timerlat_fd, and kernel threads do not need it.

	*/

	retval = osnoise_set_workload(top->context, !params->user_top);

	if (retval < -1) {

		err_msg("Failed to set OSNOISE_WORKLOAD option\n");

		goto out_err;

	}

	}



	return 0;