From: Andi Kleen <andi@firstfloor.org>
To: eranian@google.com
Cc: linux-kernel@vger.kernel.org, peterz@infradead.org,
mingo@elte.hu, paulus@samba.org, davem@davemloft.net,
fweisbec@gmail.com, perfmon2-devel@lists.sf.net,
eranian@gmail.com, robert.richter@amd.com,
markus.t.metzger@intel.com
Subject: Re: [PATCH] perf_events: improve DS/BTS/PEBS buffer allocation
Date: Mon, 13 Sep 2010 21:35:39 +0200 [thread overview]
Message-ID: <877hip4et0.fsf@basil.nowhere.org> (raw)
In-Reply-To: <4c8e3c0c.12d1d80a.73d9.ffffcf21@mx.google.com> (Stephane Eranian's message of "Mon, 13 Sep 2010 16:55:01 +0200")
Stephane Eranian <eranian@google.com> writes:
> The DS, BTS, and PEBS memory regions were allocated using kzalloc(), i.e.,
> requesting contiguous physical memory. There is no such restriction on
> DS, PEBS and BTS buffers. Using kzalloc() could lead to error in case
> no contiguous physical memory is available. BTS is requesting 64KB,
> thus it can cause issues. PEBS is currently only requesting one page.
> Both PEBS and BTS are static buffers allocated for each CPU at the
> first user. When the last user exists, the buffers are released.
DS supports page tables, but I have some doubts it really
supports page faults. vmalloc today does page faults.
I think the change is a good idea, but it will need vmalloc_sync_all()
everywhere.
-Andi
--
ak@linux.intel.com -- Speaking for myself only.
next prev parent reply other threads:[~2010-09-13 19:35 UTC|newest]
Thread overview: 29+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-09-13 14:55 [PATCH] perf_events: improve DS/BTS/PEBS buffer allocation Stephane Eranian
2010-09-13 15:08 ` Peter Zijlstra
2010-09-13 15:21 ` Stephane Eranian
2010-09-13 15:09 ` Frederic Weisbecker
2010-09-13 15:13 ` Stephane Eranian
2010-09-13 15:16 ` Peter Zijlstra
2010-09-13 15:20 ` Stephane Eranian
2010-09-13 15:24 ` Peter Zijlstra
2010-09-13 15:31 ` Stephane Eranian
2010-09-13 15:41 ` Peter Zijlstra
2010-09-13 15:51 ` Frederic Weisbecker
2010-09-13 15:55 ` Stephane Eranian
2010-09-13 17:35 ` Peter Zijlstra
2010-09-13 18:40 ` Stephane Eranian
2010-09-13 18:42 ` Peter Zijlstra
2010-09-13 18:49 ` Stephane Eranian
2010-09-13 18:57 ` Peter Zijlstra
2010-09-13 19:12 ` Stephane Eranian
2010-09-13 19:31 ` Mathieu Desnoyers
2010-09-13 19:34 ` Peter Zijlstra
2010-09-13 19:35 ` Peter Zijlstra
2010-09-13 19:42 ` Mathieu Desnoyers
2010-09-13 17:24 ` Stephane Eranian
2010-09-13 17:36 ` Peter Zijlstra
2010-09-13 19:35 ` Andi Kleen [this message]
2010-09-13 19:49 ` Peter Zijlstra
2010-09-13 20:51 ` Andi Kleen
2010-09-13 20:57 ` [perfmon2] " Luck, Tony
2010-09-13 20:34 ` H. Peter Anvin
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=877hip4et0.fsf@basil.nowhere.org \
--to=andi@firstfloor.org \
--cc=davem@davemloft.net \
--cc=eranian@gmail.com \
--cc=eranian@google.com \
--cc=fweisbec@gmail.com \
--cc=linux-kernel@vger.kernel.org \
--cc=markus.t.metzger@intel.com \
--cc=mingo@elte.hu \
--cc=paulus@samba.org \
--cc=perfmon2-devel@lists.sf.net \
--cc=peterz@infradead.org \
--cc=robert.richter@amd.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.