linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Peter Zijlstra <peterz@infradead.org>
To: Qais Yousef <qyousef@layalina.io>
Cc: Lukasz Luba <lukasz.luba@arm.com>,
	linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org,
	rafael@kernel.org, linux-pm@vger.kernel.org, rostedt@goodmis.org,
	mhiramat@kernel.org, mingo@redhat.com, juri.lelli@redhat.com,
	vincent.guittot@linaro.org, dietmar.eggemann@arm.com,
	bsegall@google.com, mgorman@suse.de, bristot@redhat.com,
	vschneid@redhat.com, delyank@fb.com, qyousef@google.com
Subject: Re: [RESEND][PATCH v2 1/3] sched/tp: Add new tracepoint to track uclamp set from user-space
Date: Thu, 6 Jul 2023 13:14:43 +0200	[thread overview]
Message-ID: <20230706111443.GH2833176@hirez.programming.kicks-ass.net> (raw)
In-Reply-To: <20230531182629.nztie5rwhjl53v3d@airbuntu>

On Wed, May 31, 2023 at 07:26:29PM +0100, Qais Yousef wrote:
> On 05/22/23 15:57, Lukasz Luba wrote:
> > The user-space can set uclamp value for a given task. It impacts task
> > placement decisions made by the scheduler. This is very useful information
> > and helps to understand the system behavior or track improvements in
> > middleware and applications which start using uclamp mechanisms and report
> > better performance in tests.
> 
> Do you mind adding a generic one instead please? And explain why we can't just
> attach to the syscall via kprobes? I think you want to bypass the permission
> checks, so maybe a generic tracepoint after that might be justifiable?
> Then anyone can use it to track how userspace has changed any attributes for
> a task, not just uclamp.

Yeah, so I'm leaning towards the same, if you want to put a tracepoint
in __sched_setscheduler(), just trace the whole attr and leave it at
that:

	trace_update_sched_attr_tp(p, attr);

or somesuch.


  parent reply	other threads:[~2023-07-06 11:15 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-05-22 14:56 [RESEND][PATCH v2 0/3] Add basic tracing for uclamp and schedutil Lukasz Luba
2023-05-22 14:57 ` [RESEND][PATCH v2 1/3] sched/tp: Add new tracepoint to track uclamp set from user-space Lukasz Luba
     [not found]   ` <20230531182629.nztie5rwhjl53v3d@airbuntu>
2023-06-21  3:25     ` Masami Hiramatsu
2023-06-30 11:49       ` Qais Yousef
2023-07-04  7:49         ` Lukasz Luba
2023-07-04 14:02           ` Qais Yousef
2023-07-06 11:14     ` Peter Zijlstra [this message]
2023-07-19 13:18       ` Lukasz Luba
2023-05-22 14:57 ` [RESEND][PATCH v2 2/3] cpufreq: schedutil: Refactor sugov_update_shared() internals Lukasz Luba
2023-06-20 17:36   ` Rafael J. Wysocki
2023-05-22 14:57 ` [RESEND][PATCH v2 3/3] schedutil: trace: Add tracing to capture filter out requests Lukasz Luba
2023-06-20 17:40   ` Rafael J. Wysocki
2023-06-20 18:08     ` Lukasz Luba
     [not found]   ` <20230531183105.r5tqpdx5axoogkzp@airbuntu>
2023-06-20 17:52     ` Lukasz Luba
2023-06-30 12:01       ` Qais Yousef
2023-06-30 13:25         ` Qais Yousef
2023-07-04  8:23           ` Lukasz Luba
2023-07-04 13:58             ` Qais Yousef

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=20230706111443.GH2833176@hirez.programming.kicks-ass.net \
    --to=peterz@infradead.org \
    --cc=bristot@redhat.com \
    --cc=bsegall@google.com \
    --cc=delyank@fb.com \
    --cc=dietmar.eggemann@arm.com \
    --cc=juri.lelli@redhat.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pm@vger.kernel.org \
    --cc=linux-trace-kernel@vger.kernel.org \
    --cc=lukasz.luba@arm.com \
    --cc=mgorman@suse.de \
    --cc=mhiramat@kernel.org \
    --cc=mingo@redhat.com \
    --cc=qyousef@google.com \
    --cc=qyousef@layalina.io \
    --cc=rafael@kernel.org \
    --cc=rostedt@goodmis.org \
    --cc=vincent.guittot@linaro.org \
    --cc=vschneid@redhat.com \
    /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).