Re: [Intel-wired-lan] [Patch V3 5/9] i40e: Use numa_mem_id() to better support memoryless node

From	Andrew Morton <akpm@linux-foundation.org>
Newsgroups	linux.kernel
Subject	Re: [Intel-wired-lan] [Patch V3 5/9] i40e: Use numa_mem_id() to better support memoryless node
Date	2015-10-08 22:30 +0200
Message-ID	<qhpZ7-5Jz-5@gated-at.bofh.it> (permalink)
References	<pYj7P-3i1-3@gated-at.bofh.it> <pYj7Q-3i1-21@gated-at.bofh.it> <pZkbv-2Gm-5@gated-at.bofh.it> <pZlKi-503-11@gated-at.bofh.it>
Organization	linux.* mail to news gateway

Show all headers | View raw

On Wed, 19 Aug 2015 17:18:15 -0700 (PDT) David Rientjes <rientjes@google.com> wrote:

> On Wed, 19 Aug 2015, Patil, Kiran wrote:
> 
> > Acked-by: Kiran Patil <kiran.patil@intel.com>
> 
> Where's the call to preempt_disable() to prevent kernels with preemption 
> from making numa_node_id() invalid during this iteration?

David asked this question twice, received no answer and now the patch
is in the maintainer tree, destined for mainline.

If I was asked this question I would respond

  The use of numa_mem_id() is racy and best-effort.  If the unlikely
  race occurs, the memory allocation will occur on the wrong node, the
  overall result being very slightly suboptimal performance.  The
  existing use of numa_node_id() suffers from the same issue.

But I'm not the person proposing the patch.  Please don't just ignore
reviewer comments!

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Back to linux.kernel | Previous | Next — Next in thread | Find similar | Unroll thread

Thread

Re: [Intel-wired-lan] [Patch V3 5/9] i40e: Use numa_mem_id() to  better support memoryless node Andrew Morton <akpm@linux-foundation.org> - 2015-10-08 22:30 +0200
  Re: [Intel-wired-lan] [Patch V3 5/9] i40e: Use numa_mem_id() to  better support memoryless node Jiang Liu <jiang.liu@linux.intel.com> - 2015-10-09 08:00 +0200
    Re: [Intel-wired-lan] [Patch V3 5/9] i40e: Use numa_mem_id() to  better support memoryless node Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> - 2015-10-09 11:10 +0200
      Re: [Intel-wired-lan] [Patch V3 5/9] i40e: Use numa_mem_id() to  better support memoryless node Jiang Liu <jiang.liu@linux.intel.com> - 2015-10-09 11:30 +0200

csiph-web