linux-arm-kernel.lists.infradead.org archive mirror
 help / color / mirror / Atom feed
From: Marc Zyngier <maz@kernel.org>
To: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Mark Rutland <mark.rutland@arm.com>,
	Mathieu Poirier <mathieu.poirier@linaro.org>,
	Peter Zijlstra <peterz@infradead.org>,
	John Garry <john.garry@huawei.com>,
	linux-kernel@vger.kernel.org,
	Arnaldo Carvalho de Melo <acme@kernel.org>,
	Suleiman Souhlal <suleiman@google.com>,
	Leo Yan <leo.yan@linaro.org>, Namhyung Kim <namhyung@kernel.org>,
	Will Deacon <will@kernel.org>,
	linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCHv3] perf kvm: add kvm-stat for arm64
Date: Fri, 18 Sep 2020 09:20:37 +0100	[thread overview]
Message-ID: <f60758eeacb4e94db698d98d6d447939@kernel.org> (raw)
In-Reply-To: <20200918003219.GC3049@jagdpanzerIV.localdomain>

On 2020-09-18 01:32, Sergey Senozhatsky wrote:
> On (20/09/17 12:53), Marc Zyngier wrote:
>> Feel free to add a *new* tracepoint instead.
> 
> Wouldn't we want a whole bunch of new tracepoints in this case?

Yes. I don't have a better solution as long as tracepoints are ABI.
Get someone to sign-off on it, and I'll happily change them.

> (almost all of the existing ones with the extra vcpu_id field).
> Right now we have 3 types of events:
> - events with no vcpu at all        // nil
> - events with vcpu_pc               // "0x%016lx", __entry->vcpu_pc
> - events with (void *)vcpu          // "vcpu: %p", __entry->vcpu
> 
> It might be helpful if we could filter out events by vcpu_id.
> But this, basically, doubles the number of events in the ringbuffer.

Only if you enable them both, right? You define new tracepoints that
do whatever you need them to do (hopefully in a cross-architecture
compliant way), and have perf to only use the new ones on arm64.
How would that double the number of events in the buffer?

         M.
-- 
Jazz is not dead. It just smells funny...

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

  reply	other threads:[~2020-09-18  8:22 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-09-17  0:36 [PATCHv3] perf kvm: add kvm-stat for arm64 Sergey Senozhatsky
2020-09-17  8:47 ` Leo Yan
2020-09-17  9:54   ` Sergey Senozhatsky
2020-09-17 10:09 ` Leo Yan
2020-09-17 10:12   ` Leo Yan
2020-09-17 10:21     ` Marc Zyngier
2020-09-17 11:00       ` Sergey Senozhatsky
2020-09-17 13:08         ` Leo Yan
2020-09-17 11:42       ` Leo Yan
2020-09-17 11:53         ` Marc Zyngier
2020-09-17 12:52           ` Leo Yan
2020-09-18  0:32           ` Sergey Senozhatsky
2020-09-18  8:20             ` Marc Zyngier [this message]
2020-09-18 10:35               ` Sergey Senozhatsky
2020-09-18 10:55                 ` Marc Zyngier

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=f60758eeacb4e94db698d98d6d447939@kernel.org \
    --to=maz@kernel.org \
    --cc=acme@kernel.org \
    --cc=john.garry@huawei.com \
    --cc=leo.yan@linaro.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mark.rutland@arm.com \
    --cc=mathieu.poirier@linaro.org \
    --cc=namhyung@kernel.org \
    --cc=peterz@infradead.org \
    --cc=sergey.senozhatsky@gmail.com \
    --cc=suleiman@google.com \
    --cc=will@kernel.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).