From: Muchun Song <songmuchun@bytedance.com>
To: mingo@redhat.com, peterz@infradead.org, juri.lelli@redhat.com,
vincent.guittot@linaro.org, dietmar.eggemann@arm.com,
rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de,
mingo@kernel.org
Cc: linux-kernel@vger.kernel.org, Muchun Song <songmuchun@bytedance.com>
Subject: [PATCH] sched/cpuacct: Fix charge cpuacct.usage_sys incorrently.
Date: Thu, 16 Apr 2020 22:18:33 +0800 [thread overview]
Message-ID: <20200416141833.50663-1-songmuchun@bytedance.com> (raw)
The user_mode(task_pt_regs(tsk)) always return true for
user thread, and false for kernel thread. So it means that
the cpuacct.usage_sys is the time that kernel thread uses
not the time that thread uses in the kernel mode. We can
use get_irq_regs() instead of task_pt_regs() to fix it.
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
---
kernel/sched/cpuacct.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/kernel/sched/cpuacct.c b/kernel/sched/cpuacct.c
index 6448b0438ffb2..edfc62554648e 100644
--- a/kernel/sched/cpuacct.c
+++ b/kernel/sched/cpuacct.c
@@ -5,6 +5,7 @@
* Based on the work by Paul Menage (menage@google.com) and Balbir Singh
* (balbir@in.ibm.com).
*/
+#include <asm/irq_regs.h>
#include "sched.h"
/* Time spent by the tasks of the CPU accounting group executing in ... */
@@ -339,7 +340,7 @@ void cpuacct_charge(struct task_struct *tsk, u64 cputime)
{
struct cpuacct *ca;
int index = CPUACCT_STAT_SYSTEM;
- struct pt_regs *regs = task_pt_regs(tsk);
+ struct pt_regs *regs = get_irq_regs();
if (regs && user_mode(regs))
index = CPUACCT_STAT_USER;
--
2.11.0
next reply other threads:[~2020-04-16 14:33 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-04-16 14:18 Muchun Song [this message]
2020-04-16 15:35 ` [PATCH] sched/cpuacct: Fix charge cpuacct.usage_sys incorrently Steven Rostedt
2020-04-16 16:01 ` Steven Rostedt
2020-04-17 3:11 ` [External] " Muchun Song
2020-04-17 3:07 ` Muchun Song
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20200416141833.50663-1-songmuchun@bytedance.com \
--to=songmuchun@bytedance.com \
--cc=bsegall@google.com \
--cc=dietmar.eggemann@arm.com \
--cc=juri.lelli@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mgorman@suse.de \
--cc=mingo@kernel.org \
--cc=mingo@redhat.com \
--cc=peterz@infradead.org \
--cc=rostedt@goodmis.org \
--cc=vincent.guittot@linaro.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).