All of lore.kernel.org
 help / color / mirror / Atom feed
From: Ingo Molnar <mingo@kernel.org>
To: Mel Gorman <mgorman@suse.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>,
	Andrea Arcangeli <aarcange@redhat.com>,
	Rik van Riel <riel@redhat.com>,
	Johannes Weiner <hannes@cmpxchg.org>,
	Hugh Dickins <hughd@google.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	Linux-MM <linux-mm@kvack.org>,
	LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 15/19] mm: numa: Add fault driven placement and migration
Date: Tue, 13 Nov 2012 11:45:30 +0100	[thread overview]
Message-ID: <20121113104530.GF21522@gmail.com> (raw)
In-Reply-To: <1352193295-26815-16-git-send-email-mgorman@suse.de>


* Mel Gorman <mgorman@suse.de> wrote:

> NOTE: This patch is based on "sched, numa, mm: Add fault driven
>	placement and migration policy" but as it throws away 
>	all the policy to just leave a basic foundation I had to 
>	drop the signed-offs-by.

So, much of that has been updated meanwhile - but the split 
makes fundamental sense - we considered it before.

One detail you did in this patch was the following rename:

     s/EMBEDDED_NUMA/NUMA_VARIABLE_LOCALITY

> --- a/arch/sh/mm/Kconfig
> +++ b/arch/sh/mm/Kconfig
> @@ -111,6 +111,7 @@ config VSYSCALL
>  config NUMA
>  	bool "Non Uniform Memory Access (NUMA) Support"
>  	depends on MMU && SYS_SUPPORTS_NUMA && EXPERIMENTAL
> +	select NUMA_VARIABLE_LOCALITY
>  	default n
>  	help
>  	  Some SH systems have many various memories scattered around
> diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
>
..aaba45d 100644
> --- a/init/Kconfig
> +++ b/init/Kconfig
> @@ -696,6 +696,20 @@ config LOG_BUF_SHIFT
>  config HAVE_UNSTABLE_SCHED_CLOCK
>  	bool
>  
> +#
> +# For architectures that (ab)use NUMA to represent different memory regions
> +# all cpu-local but of different latencies, such as SuperH.
> +#
> +config NUMA_VARIABLE_LOCALITY
> +	bool

The NUMA_VARIABLE_LOCALITY name slightly misses the real point 
though that NUMA_EMBEDDED tried to stress: it's important to 
realize that these are systems that (ab-)use our NUMA memory 
zoning code to implement support for variable speed RAM modules 
- so they can use the existing node binding ABIs.

The cost of that is the losing of the regular NUMA node 
structure. So by all means it's a convenient hack - but the name 
must signal that. I'm not attached to the NUMA_EMBEDDED naming 
overly strongly, but NUMA_VARIABLE_LOCALITY sounds more harmless 
than it should.

Perhaps ARCH_WANT_NUMA_VARIABLE_LOCALITY_OVERRIDE? A tad long 
but we don't want it to be overused in any case.

Thanks,

	Ingo

--
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>

WARNING: multiple messages have this Message-ID (diff)
From: Ingo Molnar <mingo@kernel.org>
To: Mel Gorman <mgorman@suse.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>,
	Andrea Arcangeli <aarcange@redhat.com>,
	Rik van Riel <riel@redhat.com>,
	Johannes Weiner <hannes@cmpxchg.org>,
	Hugh Dickins <hughd@google.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	Linux-MM <linux-mm@kvack.org>,
	LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 15/19] mm: numa: Add fault driven placement and migration
Date: Tue, 13 Nov 2012 11:45:30 +0100	[thread overview]
Message-ID: <20121113104530.GF21522@gmail.com> (raw)
In-Reply-To: <1352193295-26815-16-git-send-email-mgorman@suse.de>


* Mel Gorman <mgorman@suse.de> wrote:

> NOTE: This patch is based on "sched, numa, mm: Add fault driven
>	placement and migration policy" but as it throws away 
>	all the policy to just leave a basic foundation I had to 
>	drop the signed-offs-by.

So, much of that has been updated meanwhile - but the split 
makes fundamental sense - we considered it before.

One detail you did in this patch was the following rename:

     s/EMBEDDED_NUMA/NUMA_VARIABLE_LOCALITY

> --- a/arch/sh/mm/Kconfig
> +++ b/arch/sh/mm/Kconfig
> @@ -111,6 +111,7 @@ config VSYSCALL
>  config NUMA
>  	bool "Non Uniform Memory Access (NUMA) Support"
>  	depends on MMU && SYS_SUPPORTS_NUMA && EXPERIMENTAL
> +	select NUMA_VARIABLE_LOCALITY
>  	default n
>  	help
>  	  Some SH systems have many various memories scattered around
> diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
>
..aaba45d 100644
> --- a/init/Kconfig
> +++ b/init/Kconfig
> @@ -696,6 +696,20 @@ config LOG_BUF_SHIFT
>  config HAVE_UNSTABLE_SCHED_CLOCK
>  	bool
>  
> +#
> +# For architectures that (ab)use NUMA to represent different memory regions
> +# all cpu-local but of different latencies, such as SuperH.
> +#
> +config NUMA_VARIABLE_LOCALITY
> +	bool

The NUMA_VARIABLE_LOCALITY name slightly misses the real point 
though that NUMA_EMBEDDED tried to stress: it's important to 
realize that these are systems that (ab-)use our NUMA memory 
zoning code to implement support for variable speed RAM modules 
- so they can use the existing node binding ABIs.

The cost of that is the losing of the regular NUMA node 
structure. So by all means it's a convenient hack - but the name 
must signal that. I'm not attached to the NUMA_EMBEDDED naming 
overly strongly, but NUMA_VARIABLE_LOCALITY sounds more harmless 
than it should.

Perhaps ARCH_WANT_NUMA_VARIABLE_LOCALITY_OVERRIDE? A tad long 
but we don't want it to be overused in any case.

Thanks,

	Ingo

  parent reply	other threads:[~2012-11-13 10:45 UTC|newest]

Thread overview: 129+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-11-06  9:14 [RFC PATCH 00/19] Foundation for automatic NUMA balancing Mel Gorman
2012-11-06  9:14 ` Mel Gorman
2012-11-06  9:14 ` [PATCH 01/19] mm: compaction: Move migration fail/success stats to migrate.c Mel Gorman
2012-11-06  9:14   ` Mel Gorman
2012-11-06 17:32   ` Rik van Riel
2012-11-06 17:32     ` Rik van Riel
2012-11-06  9:14 ` [PATCH 02/19] mm: migrate: Add a tracepoint for migrate_pages Mel Gorman
2012-11-06  9:14   ` Mel Gorman
2012-11-06 17:33   ` Rik van Riel
2012-11-06 17:33     ` Rik van Riel
2012-11-06  9:14 ` [PATCH 03/19] mm: compaction: Add scanned and isolated counters for compaction Mel Gorman
2012-11-06  9:14   ` Mel Gorman
2012-11-06 17:35   ` Rik van Riel
2012-11-06 17:35     ` Rik van Riel
2012-11-06  9:14 ` [PATCH 04/19] mm: numa: define _PAGE_NUMA Mel Gorman
2012-11-06  9:14   ` Mel Gorman
2012-11-06 18:35   ` Rik van Riel
2012-11-06 18:35     ` Rik van Riel
2012-11-06  9:14 ` [PATCH 05/19] mm: numa: pte_numa() and pmd_numa() Mel Gorman
2012-11-06  9:14   ` Mel Gorman
2012-11-13  9:54   ` Ingo Molnar
2012-11-13  9:54     ` Ingo Molnar
2012-11-13 11:24     ` Mel Gorman
2012-11-13 11:24       ` Mel Gorman
2012-11-06  9:14 ` [PATCH 06/19] mm: numa: teach gup_fast about pmd_numa Mel Gorman
2012-11-06  9:14   ` Mel Gorman
2012-11-13 10:07   ` Ingo Molnar
2012-11-13 10:07     ` Ingo Molnar
2012-11-13 11:37     ` Mel Gorman
2012-11-13 11:37       ` Mel Gorman
2012-11-13 13:51       ` Ingo Molnar
2012-11-13 13:51         ` Ingo Molnar
2012-11-06  9:14 ` [PATCH 07/19] mm: numa: split_huge_page: transfer the NUMA type from the pmd to the pte Mel Gorman
2012-11-06  9:14   ` Mel Gorman
2012-11-06  9:14 ` [PATCH 08/19] mm: numa: Create basic numa page hinting infrastructure Mel Gorman
2012-11-06  9:14   ` Mel Gorman
2012-11-06 18:58   ` Rik van Riel
2012-11-06 18:58     ` Rik van Riel
2012-11-07 10:38     ` Mel Gorman
2012-11-07 10:38       ` Mel Gorman
2012-11-07 10:48       ` Rik van Riel
2012-11-07 10:48         ` Rik van Riel
2012-11-07 11:00         ` Mel Gorman
2012-11-07 11:00           ` Mel Gorman
2012-11-13 10:21   ` Ingo Molnar
2012-11-13 10:21     ` Ingo Molnar
2012-11-13 11:50     ` Mel Gorman
2012-11-13 11:50       ` Mel Gorman
2012-11-13 13:49       ` Ingo Molnar
2012-11-13 13:49         ` Ingo Molnar
2012-11-13 14:26         ` Mel Gorman
2012-11-13 14:26           ` Mel Gorman
2012-11-06  9:14 ` [PATCH 09/19] mm: mempolicy: Make MPOL_LOCAL a real policy Mel Gorman
2012-11-06  9:14   ` Mel Gorman
2012-11-06  9:14 ` [PATCH 10/19] mm: mempolicy: Add MPOL_MF_NOOP Mel Gorman
2012-11-06  9:14   ` Mel Gorman
2012-11-06  9:14 ` [PATCH 11/19] mm: mempolicy: Check for misplaced page Mel Gorman
2012-11-06  9:14   ` Mel Gorman
2012-11-06  9:14 ` [PATCH 12/19] mm: migrate: Introduce migrate_misplaced_page() Mel Gorman
2012-11-06  9:14   ` Mel Gorman
2012-11-06 19:10   ` Rik van Riel
2012-11-06 19:10     ` Rik van Riel
2012-11-13  9:36   ` Ingo Molnar
2012-11-13  9:36     ` Ingo Molnar
2012-11-13 11:43     ` Ingo Molnar
2012-11-13 11:56       ` Mel Gorman
2012-11-13 11:56         ` Mel Gorman
2012-11-13 14:49       ` Rik van Riel
2012-11-13 14:49         ` Rik van Riel
2012-11-06  9:14 ` [PATCH 13/19] mm: mempolicy: Use _PAGE_NUMA to migrate pages Mel Gorman
2012-11-06  9:14   ` Mel Gorman
2012-11-06 19:18   ` Rik van Riel
2012-11-06 19:18     ` Rik van Riel
2012-11-07 12:32     ` Mel Gorman
2012-11-07 12:32       ` Mel Gorman
2012-11-06  9:14 ` [PATCH 14/19] mm: mempolicy: Add MPOL_MF_LAZY Mel Gorman
2012-11-06  9:14   ` Mel Gorman
2012-11-06 19:19   ` Rik van Riel
2012-11-06 19:19     ` Rik van Riel
2012-11-13 10:25   ` Ingo Molnar
2012-11-13 10:25     ` Ingo Molnar
2012-11-13 12:02     ` Mel Gorman
2012-11-13 12:02       ` Mel Gorman
2012-11-06  9:14 ` [PATCH 15/19] mm: numa: Add fault driven placement and migration Mel Gorman
2012-11-06  9:14   ` Mel Gorman
2012-11-06 19:41   ` Rik van Riel
2012-11-06 19:41     ` Rik van Riel
2012-11-07 10:49     ` Mel Gorman
2012-11-07 10:49       ` Mel Gorman
2012-11-07 11:46       ` Rik van Riel
2012-11-07 11:46         ` Rik van Riel
2012-11-13 10:45   ` Ingo Molnar [this message]
2012-11-13 10:45     ` Ingo Molnar
2012-11-13 12:09     ` Mel Gorman
2012-11-13 12:09       ` Mel Gorman
2012-11-13 13:39       ` Ingo Molnar
2012-11-13 13:39         ` Ingo Molnar
2012-11-06  9:14 ` [PATCH 16/19] mm: numa: Add pte updates, hinting and migration stats Mel Gorman
2012-11-06  9:14   ` Mel Gorman
2012-11-06 19:55   ` Rik van Riel
2012-11-06 19:55     ` Rik van Riel
2012-11-07 10:57     ` Mel Gorman
2012-11-07 10:57       ` Mel Gorman
2012-11-07 11:47       ` Rik van Riel
2012-11-07 11:47         ` Rik van Riel
2012-11-06  9:14 ` [PATCH 17/19] mm: numa: Migrate on reference policy Mel Gorman
2012-11-06  9:14   ` Mel Gorman
2012-11-07 11:56   ` Rik van Riel
2012-11-07 11:56     ` Rik van Riel
2012-11-06  9:14 ` [PATCH 18/19] mm: sched: numa: Implement constant, per task Working Set Sampling (WSS) rate Mel Gorman
2012-11-06  9:14   ` Mel Gorman
2012-11-06 19:55   ` Rik van Riel
2012-11-06 19:55     ` Rik van Riel
2012-11-06  9:14 ` [PATCH 19/19] mm: sched: numa: Implement slow start for working set sampling Mel Gorman
2012-11-06  9:14   ` Mel Gorman
2012-11-06 19:56   ` Rik van Riel
2012-11-06 19:56     ` Rik van Riel
2012-11-07  9:27 ` [RFC PATCH 00/19] Foundation for automatic NUMA balancing Zhouping Liu
2012-11-07 15:25   ` Mel Gorman
2012-11-07 15:25     ` Mel Gorman
2012-11-08  6:37     ` Zhouping Liu
2012-11-08  6:37       ` Zhouping Liu
2012-11-08  6:39       ` 杨竹
2012-11-08  7:03         ` Zhouping Liu
2012-11-08  7:03           ` Zhouping Liu
2012-11-09 14:42 ` Andrea Arcangeli
2012-11-09 14:42   ` Andrea Arcangeli
2012-11-09 16:12   ` Mel Gorman
2012-11-09 16:12     ` Mel Gorman

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=20121113104530.GF21522@gmail.com \
    --to=mingo@kernel.org \
    --cc=a.p.zijlstra@chello.nl \
    --cc=aarcange@redhat.com \
    --cc=akpm@linux-foundation.org \
    --cc=hannes@cmpxchg.org \
    --cc=hughd@google.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=mgorman@suse.de \
    --cc=riel@redhat.com \
    --cc=tglx@linutronix.de \
    --cc=torvalds@linux-foundation.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 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.