From: Anshuman Khandual <khandual@linux.vnet.ibm.com>
To: Michael Ellerman <mpe@ellerman.id.au>, linuxppc-dev@ozlabs.org
Cc: mikey@neuling.org, sukadev@linux.vnet.ibm.com, dja@axtens.net
Subject: Re: [3/5] powerpc/perf: Replace last usage of get_cpu_var with this_cpu_ptr
Date: Tue, 28 Jul 2015 09:07:08 +0530 [thread overview]
Message-ID: <55B6F8E4.2050007@linux.vnet.ibm.com> (raw)
In-Reply-To: <20150727051530.325AE1402C6@ozlabs.org>
On 07/27/2015 10:45 AM, Michael Ellerman wrote:
> On Tue, 2015-30-06 at 08:20:29 UTC, Anshuman Khandual wrote:
>> > The commit 69111bac42f5ce ("powerpc: Replace __get_cpu_var uses")
>> > replaced all usage of get_cpu_var with this_cpu_ptr inside core
>> > perf event handling on powerpc. But it skipped one of them which
>> > is being replaced with this patch.
> No it replaced all uses of __get_cpu_var(), not get_cpu_var(). The difference
> is important.
Hmm, I see. Was not aware about it. Daniel suggested on this and I
thought it made sense. Hence proposed the change.
>
> get_cpu_var() disables preemption for you, so it's only safe to switch to
> this_cpu_ptr() if preemption is already disabled. Is it?
We dont disable preemption inside power_pmu_event_init neither inside
perf_try_init_event where it gets called from, I guess the answer is NO.
Will drop this patch next time around.
next prev parent reply other threads:[~2015-07-28 3:37 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-06-30 8:20 [PATCH 0/5] BHRB fixes, improvements and cleanups Anshuman Khandual
2015-06-30 8:20 ` [PATCH 1/5] powerpc/perf: Drop the branch sample when 'from' cannot be fetched Anshuman Khandual
2015-07-27 4:19 ` [1/5] " Michael Ellerman
2015-07-28 3:08 ` Anshuman Khandual
2015-09-30 9:03 ` Anshuman Khandual
2015-09-30 10:46 ` Michael Ellerman
2015-06-30 8:20 ` [PATCH 2/5] powerpc/perf: Change type of the bhrb_users variable Anshuman Khandual
2015-08-03 1:35 ` [2/5] " Michael Ellerman
2015-06-30 8:20 ` [PATCH 3/5] powerpc/perf: Replace last usage of get_cpu_var with this_cpu_ptr Anshuman Khandual
2015-07-27 5:15 ` [3/5] " Michael Ellerman
2015-07-28 3:37 ` Anshuman Khandual [this message]
2015-06-30 8:20 ` [PATCH 4/5] powerpc/perf: Change name & type of 'pred' in power_pmu_bhrb_read Anshuman Khandual
2015-07-29 3:25 ` [4/5] " Michael Ellerman
2015-07-29 8:13 ` Anshuman Khandual
2015-06-30 8:20 ` [PATCH 5/5] powerpc/perf: Re organize PMU branch filter processing on POWER8 Anshuman Khandual
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=55B6F8E4.2050007@linux.vnet.ibm.com \
--to=khandual@linux.vnet.ibm.com \
--cc=dja@axtens.net \
--cc=linuxppc-dev@ozlabs.org \
--cc=mikey@neuling.org \
--cc=mpe@ellerman.id.au \
--cc=sukadev@linux.vnet.ibm.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).