From: Andrew Morton <akpm@linux-foundation.org>
To: Ingo Molnar <mingo@kernel.org>
Cc: Dave Hansen <dave@sr71.net>,
linux-kernel@vger.kernel.org, x86@kernel.org, linux-mm@kvack.org,
Peter Zijlstra <a.p.zijlstra@chello.nl>
Subject: Re: [RESEND][PATCH] mm: vmstats: tlb flush counters
Date: Thu, 18 Jul 2013 13:51:57 -0700 [thread overview]
Message-ID: <20130718135157.2262e28b2c6e0f43a4d0fe7a@linux-foundation.org> (raw)
In-Reply-To: <20130717072100.GA14359@gmail.com>
On Wed, 17 Jul 2013 09:21:00 +0200 Ingo Molnar <mingo@kernel.org> wrote:
>
> * Dave Hansen <dave@sr71.net> wrote:
>
> > I was investigating some TLB flush scaling issues and realized
> > that we do not have any good methods for figuring out how many
> > TLB flushes we are doing.
> >
> > It would be nice to be able to do these in generic code, but the
> > arch-independent calls don't explicitly specify whether we
> > actually need to do remote flushes or not. In the end, we really
> > need to know if we actually _did_ global vs. local invalidations,
> > so that leaves us with few options other than to muck with the
> > counters from arch-specific code.
Spose so, if you really think it's worth it. It's all downside for
uniprocessor machines. And for architectures which don't implement the
counters, of course.
> > --- linux.git/include/linux/vm_event_item.h~tlb-vmstats 2013-07-16 16:41:56.478280438 -0700
> > +++ linux.git-davehans/include/linux/vm_event_item.h 2013-07-16 16:41:56.483280658 -0700
> > @@ -70,6 +70,11 @@ enum vm_event_item { PGPGIN, PGPGOUT, PS
> > THP_ZERO_PAGE_ALLOC,
> > THP_ZERO_PAGE_ALLOC_FAILED,
> > #endif
> >
> > + NR_TLB_REMOTE_FLUSH, /* cpu tried to flush others' tlbs */
> > + NR_TLB_REMOTE_FLUSH_RECEIVED,/* cpu received ipi for flush */
> > + NR_TLB_LOCAL_FLUSH_ALL,
> > + NR_TLB_LOCAL_FLUSH_ONE,
> > + NR_TLB_LOCAL_FLUSH_ONE_KERNEL,
>
> Please fix the vertical alignment of comments.
I looked - this isn't practical.
It would be nice to actually document these things though. We don't
*have* to squeeze the comment into the RHS.
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
next prev parent reply other threads:[~2013-07-18 20:51 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-07-16 23:44 Dave Hansen
2013-07-17 7:21 ` Ingo Molnar
2013-07-18 20:51 ` Andrew Morton [this message]
2013-07-19 8:28 ` Ingo Molnar
2013-07-19 15:51 ` Dave Hansen
2013-07-19 11:38 ` Raghavendra KT
2013-07-19 15:20 ` Dave Hansen
2013-07-20 13:09 ` Raghavendra K T
2013-07-22 10:06 ` Ingo Molnar
2013-07-22 16:59 ` Dave Hansen
2013-07-23 8:17 ` Ingo Molnar
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=20130718135157.2262e28b2c6e0f43a4d0fe7a@linux-foundation.org \
--to=akpm@linux-foundation.org \
--cc=a.p.zijlstra@chello.nl \
--cc=dave@sr71.net \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mingo@kernel.org \
--cc=x86@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