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From: Andrew Morton <akpm@linux-foundation.org>
To: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: linux-mm@kvack.org, linux-numa@vger.kernel.org,
	Tejun Heo <tj@kernel.org>, Mel Gorman <mel@csn.ul.ie>,
	andi@firstfloor.org, Christoph Lameter <cl@linux-foundation.org>,
	Nick Piggin <npiggin@suse.de>,
	David Rientjes <rientjes@google.com>,
	eric.whitney@hp.com,
	KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>,
	linux-arch@vger.kernel.org
Subject: Re: [PATCH 1/8] numa:  add generic percpu var numa_node_id() implementation
Date: Fri, 16 Apr 2010 13:33:24 -0700	[thread overview]
Message-ID: <20100416133324.fcb1c168.akpm@linux-foundation.org> (raw)
In-Reply-To: <20100415172956.8801.18133.sendpatchset@localhost.localdomain>

On Thu, 15 Apr 2010 13:29:56 -0400
Lee Schermerhorn <lee.schermerhorn@hp.com> wrote:

> Rework the generic version of the numa_node_id() function to use the
> new generic percpu variable infrastructure.
> 
> Guard the new implementation with a new config option:
> 
>         CONFIG_USE_PERCPU_NUMA_NODE_ID.
> 
> Archs which support this new implemention will default this option
> to 'y' when NUMA is configured.  This config option could be removed
> if/when all archs switch over to the generic percpu implementation
> of numa_node_id().  Arch support involves:
> 
>   1) converting any existing per cpu variable implementations to use
>      this implementation.  x86_64 is an instance of such an arch.
>   2) archs that don't use a per cpu variable for numa_node_id() will
>      need to initialize the new per cpu variable "numa_node" as cpus
>      are brought on-line.  ia64 is an example.
>   3) Defining USE_PERCPU_NUMA_NODE_ID in arch dependent Kconfig--e.g.,
>      when NUMA is configured.  This is required because I have
>      retained the old implementation by default to allow archs to
>      be modified incrementally, as desired.
> 
> Subsequent patches will convert x86_64 and ia64 to use this
> implemenation.

So which arches _aren't_ converted?  powerpc, sparc and alpha?

Is there sufficient info here for the maintainers to be able to
perform the conversion with minimal head-scratching?

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WARNING: multiple messages have this Message-ID (diff)
From: Andrew Morton <akpm@linux-foundation.org>
To: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: linux-mm@kvack.org, linux-numa@vger.kernel.org,
	Tejun Heo <tj@kernel.org>, Mel Gorman <mel@csn.ul.ie>,
	andi@firstfloor.org, Christoph Lameter <cl@linux-foundation.org>,
	Nick Piggin <npiggin@suse.de>,
	David Rientjes <rientjes@google.com>,
	eric.whitney@hp.com,
	KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>,
	linux-arch@vger.kernel.org
Subject: Re: [PATCH 1/8] numa:  add generic percpu var numa_node_id() implementation
Date: Fri, 16 Apr 2010 13:33:24 -0700	[thread overview]
Message-ID: <20100416133324.fcb1c168.akpm@linux-foundation.org> (raw)
Message-ID: <20100416203324.2XKtVNPomPxY9tilcbkHcvM-GxRtGZ6PFuZy1W3TlRw@z> (raw)
In-Reply-To: <20100415172956.8801.18133.sendpatchset@localhost.localdomain>

On Thu, 15 Apr 2010 13:29:56 -0400
Lee Schermerhorn <lee.schermerhorn@hp.com> wrote:

> Rework the generic version of the numa_node_id() function to use the
> new generic percpu variable infrastructure.
> 
> Guard the new implementation with a new config option:
> 
>         CONFIG_USE_PERCPU_NUMA_NODE_ID.
> 
> Archs which support this new implemention will default this option
> to 'y' when NUMA is configured.  This config option could be removed
> if/when all archs switch over to the generic percpu implementation
> of numa_node_id().  Arch support involves:
> 
>   1) converting any existing per cpu variable implementations to use
>      this implementation.  x86_64 is an instance of such an arch.
>   2) archs that don't use a per cpu variable for numa_node_id() will
>      need to initialize the new per cpu variable "numa_node" as cpus
>      are brought on-line.  ia64 is an example.
>   3) Defining USE_PERCPU_NUMA_NODE_ID in arch dependent Kconfig--e.g.,
>      when NUMA is configured.  This is required because I have
>      retained the old implementation by default to allow archs to
>      be modified incrementally, as desired.
> 
> Subsequent patches will convert x86_64 and ia64 to use this
> implemenation.

So which arches _aren't_ converted?  powerpc, sparc and alpha?

Is there sufficient info here for the maintainers to be able to
perform the conversion with minimal head-scratching?

       reply	other threads:[~2010-04-16 20:33 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <20100415172950.8801.60358.sendpatchset@localhost.localdomain>
     [not found] ` <20100415172956.8801.18133.sendpatchset@localhost.localdomain>
2010-04-16 20:33   ` Andrew Morton [this message]
2010-04-16 20:33     ` [PATCH 1/8] numa: add generic percpu var numa_node_id() implementation Andrew Morton
2010-04-19 13:22     ` Lee Schermerhorn
2010-04-19 13:22       ` Lee Schermerhorn

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