LKML Archive on
help / color / mirror / Atom feed
From: "stephane eranian" <>
To: "Metzger, Markus T" <>
Cc: "Roland McGrath" <>,
	"Ingo Molnar" <>,,
Subject: Re: ptrace API extensions for BTS
Date: Wed, 30 Jan 2008 14:39:29 +0100	[thread overview]
Message-ID: <> (raw)
In-Reply-To: <>


On Jan 30, 2008 1:52 PM, Metzger, Markus T <> wrote:
> >From: stephane eranian []
> >Sent: Mittwoch, 30. Januar 2008 12:01
> >You can get information about the perfmon2 project at:
> >
> I downloaded your patch for 2.6.23 and cloned your git repository.
> From a first glance, it looks like there is indeed a lot of overlap.
> >I would like to take a look at your patches. Where can I get them?
> You can find the changes in the mm branch of the x86 git. Do they keep
> the patches there, somewhere, as well?

I will take a look at what you have in -mm git.

> You should get the best overview if you look at arch/x86/kernel/ds.c,
> include/asm-x86/ds.h, include/asm-x86/ptrace-abi.h, and
> arch/x86/kernel/ptrace.c or simply grep for BTS.

> >My understanding at this point is that we would need to coordinate
> >access to the
> >DS_AREA. It would likely have to be mutually exclusive access.
> From a brief look at your patch, I would say that we should rather
> combine the configuration and collection part. They are very similar.
That's probably fine too. I'll let you know once I know more about your code.

> We might still want to provide different interfaces on top of it.
> In particular, I think the ptrace interface is most appropriate for
> debuggers.

I agree.

> >Now, there is some preliminary perf. MSR allocator in the kernel.
> >However, it does not know
> >of all available MSRs out there. It focuses on the counters mostly.
> >Perfmon, oprofile and
> >the NMI watchdog use it. I think it could be generalized to other MSR
> >(non-contiguous).
> >
> >I would be happy to work with you in refining this MSR allocator.
> Are you planning to get the perfmon patch into the kernel? Or do you
> want it to remain a separate patch?

The former, i.e., trying to merge with mainline.

> In the first case, we should try to merge the features. In the second
> case, refining the MSR allocator would probably be best.

  reply	other threads:[~2008-01-30 13:39 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-12-07  9:11 Metzger, Markus T
2007-12-07 11:18 ` Andi Kleen
2007-12-07 12:01   ` Metzger, Markus T
2007-12-07 13:04     ` Andi Kleen
2007-12-07 13:36       ` Metzger, Markus T
2008-01-30  7:25 ` Roland McGrath
2008-01-30 10:32   ` Metzger, Markus T
2008-01-30 11:01     ` stephane eranian
2008-01-30 12:52       ` Metzger, Markus T
2008-01-30 13:39         ` stephane eranian [this message]
2008-01-31 11:15         ` stephane eranian
2008-01-31 17:45           ` Metzger, Markus T

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:

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \ \ \ \ \ \ \ \
    --subject='Re: ptrace API extensions for BTS' \

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

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).