linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: Mel Gorman <mgorman@suse.de>
To: Joonsoo Kim <js1304@gmail.com>
Cc: Pekka Enberg <penberg@kernel.org>,
	linux-kernel@vger.kernel.org, linux-mm@kvack.org,
	Christoph Lameter <cl@linux-foundation.org>
Subject: Re: [PATCH 1/2] slab:  do ClearSlabPfmemalloc() for all pages of slab
Date: Mon, 3 Sep 2012 11:08:55 +0100	[thread overview]
Message-ID: <20120903100855.GA11266@suse.de> (raw)
In-Reply-To: <1345903871-1921-1-git-send-email-js1304@gmail.com>

It took me a while to getting around to reviewing this due to attending
kernel summit. Sorry about that.

On Sat, Aug 25, 2012 at 11:11:10PM +0900, Joonsoo Kim wrote:
> Now, we just do ClearSlabPfmemalloc() for first page of slab
> when we clear SlabPfmemalloc flag. It is a problem because we sometimes
> test flag of page which is not first page of slab in __ac_put_obj().
> 

Well spotted.

The impact is marginal as far as pfmemalloc protection is concerned. I do not
believe that any of the slabs that use high-order allocations are used in for
the swap-over-network paths. It would be unfortunate if that ever changed.

> So add code to do ClearSlabPfmemalloc for all pages of slab.
> 

I would prefer if the pfmemalloc information was kept on the head page.
Would the following patch also address your concerns?

diff --git a/mm/slab.c b/mm/slab.c
index 811af03..d34a903 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -1000,7 +1000,7 @@ static void *__ac_get_obj(struct kmem_cache *cachep, struct array_cache *ac,
 		l3 = cachep->nodelists[numa_mem_id()];
 		if (!list_empty(&l3->slabs_free) && force_refill) {
 			struct slab *slabp = virt_to_slab(objp);
-			ClearPageSlabPfmemalloc(virt_to_page(slabp->s_mem));
+			ClearPageSlabPfmemalloc(virt_to_head_page(slabp->s_mem));
 			clear_obj_pfmemalloc(&objp);
 			recheck_pfmemalloc_active(cachep, ac);
 			return objp;
@@ -1032,7 +1032,7 @@ static void *__ac_put_obj(struct kmem_cache *cachep, struct array_cache *ac,
 {
 	if (unlikely(pfmemalloc_active)) {
 		/* Some pfmemalloc slabs exist, check if this is one */
-		struct page *page = virt_to_page(objp);
+		struct page *page = virt_to_head_page(objp);
 		if (PageSlabPfmemalloc(page))
 			set_obj_pfmemalloc(&objp);
 	}

-- 
Mel Gorman
SUSE Labs

--
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>

  parent reply	other threads:[~2012-09-03 10:09 UTC|newest]

Thread overview: 95+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <Yes>
2012-07-16 16:14 ` [PATCH 1/3] mm: correct return value of migrate_pages() Joonsoo Kim
2012-07-16 16:14   ` [PATCH 2/3] mm: fix possible incorrect return value of migrate_pages() syscall Joonsoo Kim
2012-07-16 17:26     ` Christoph Lameter
2012-07-16 17:40     ` Michal Nazarewicz
2012-07-16 17:59       ` JoonSoo Kim
2012-07-17 13:02         ` Michal Nazarewicz
2012-07-16 16:14   ` [PATCH 3/3] mm: fix return value in __alloc_contig_migrate_range() Joonsoo Kim
2012-07-16 17:29     ` Christoph Lameter
2012-07-16 17:40     ` Michal Nazarewicz
2012-07-16 18:40       ` JoonSoo Kim
2012-07-17 13:16         ` Michal Nazarewicz
2012-07-16 17:14   ` [PATCH 4] mm: fix possible incorrect return value of move_pages() syscall Joonsoo Kim
2012-07-16 17:30     ` Christoph Lameter
2012-07-16 17:23   ` [PATCH 1/3] mm: correct return value of migrate_pages() Christoph Lameter
2012-07-16 17:32     ` JoonSoo Kim
2012-07-16 17:37       ` Christoph Lameter
2012-07-16 17:40   ` Michal Nazarewicz
2012-07-16 17:57     ` JoonSoo Kim
2012-07-16 18:05       ` Christoph Lameter
2012-07-17 12:33 ` [PATCH 1/4 v2] mm: correct return value of migrate_pages() and migrate_huge_pages() Joonsoo Kim
2012-07-17 12:33   ` [PATCH 2/4 v2] mm: fix possible incorrect return value of migrate_pages() syscall Joonsoo Kim
2012-07-17 14:28     ` Christoph Lameter
2012-07-17 15:41       ` JoonSoo Kim
2012-07-17 12:33   ` [PATCH 3/4 v2] mm: fix return value in __alloc_contig_migrate_range() Joonsoo Kim
2012-07-17 13:25     ` Michal Nazarewicz
2012-07-17 15:45       ` JoonSoo Kim
2012-07-17 15:49         ` [PATCH 3/4 v3] " Joonsoo Kim
2012-07-17 12:33   ` [PATCH 4/4 v2] mm: fix possible incorrect return value of move_pages() syscall Joonsoo Kim
2012-07-27 17:55 ` [RESEND PATCH 1/4 v3] mm: correct return value of migrate_pages() and migrate_huge_pages() Joonsoo Kim
2012-07-27 17:55   ` [RESEND PATCH 2/4 v3] mm: fix possible incorrect return value of migrate_pages() syscall Joonsoo Kim
2012-07-27 20:57     ` Christoph Lameter
2012-07-28  6:16       ` JoonSoo Kim
2012-07-30 19:30         ` Christoph Lameter
2012-07-27 17:55   ` [RESEND PATCH 3/4 v3] mm: fix return value in __alloc_contig_migrate_range() Joonsoo Kim
2012-07-27 17:55   ` [RESEND PATCH 4/4 v3] mm: fix possible incorrect return value of move_pages() syscall Joonsoo Kim
2012-07-27 20:54     ` Christoph Lameter
2012-07-28  6:09       ` JoonSoo Kim
2012-07-30 19:29         ` Christoph Lameter
2012-07-31  3:34           ` JoonSoo Kim
2012-07-31 14:04             ` Christoph Lameter
2012-08-01  5:15           ` Michael Kerrisk
2012-08-01 18:00             ` Christoph Lameter
2012-08-02  5:52               ` Michael Kerrisk
2012-08-24 16:05 ` [PATCH 1/2] slub: rename cpu_partial to max_cpu_object Joonsoo Kim
2012-08-24 16:05   ` [PATCH 2/2] slub: correct the calculation of the number of cpu objects in get_partial_node Joonsoo Kim
2012-08-24 16:15     ` Christoph Lameter
2012-08-24 16:28       ` JoonSoo Kim
2012-08-24 16:31         ` Christoph Lameter
2012-08-24 16:40           ` JoonSoo Kim
2012-08-24 16:12   ` [PATCH 1/2] slub: rename cpu_partial to max_cpu_object Christoph Lameter
2012-08-25 14:11 ` [PATCH 1/2] slab: do ClearSlabPfmemalloc() for all pages of slab Joonsoo Kim
2012-08-25 14:11   ` [PATCH 2/2] slab: fix starting index for finding another object Joonsoo Kim
2012-09-03 10:08   ` Mel Gorman [this message]
2012-10-20 15:48 ` [PATCH for-v3.7 1/2] slub: optimize poorly inlined kmalloc* functions Joonsoo Kim
2012-10-20 15:48   ` [PATCH for-v3.7 2/2] slub: optimize kmalloc* inlining for GFP_DMA Joonsoo Kim
2012-10-22 14:31     ` Christoph Lameter
2012-10-23  2:29       ` JoonSoo Kim
2012-10-23  6:16         ` Eric Dumazet
2012-10-23 16:12           ` JoonSoo Kim
2012-10-24  8:05   ` [PATCH for-v3.7 1/2] slub: optimize poorly inlined kmalloc* functions Pekka Enberg
2012-10-24 13:36     ` Christoph Lameter
2012-10-28 19:12 ` [PATCH 0/5] minor clean-up and optimize highmem related code Joonsoo Kim
2012-10-28 19:12   ` [PATCH 1/5] mm, highmem: use PKMAP_NR() to calculate an index of pkmap Joonsoo Kim
2012-10-29  1:48     ` Minchan Kim
2012-10-28 19:12   ` [PATCH 2/5] mm, highmem: remove useless pool_lock Joonsoo Kim
2012-10-29  1:52     ` Minchan Kim
2012-10-30 21:31     ` Andrew Morton
2012-10-31  5:14       ` Minchan Kim
2012-10-31 15:01       ` JoonSoo Kim
2012-10-28 19:12   ` [PATCH 3/5] mm, highmem: remove page_address_pool list Joonsoo Kim
2012-10-29  1:57     ` Minchan Kim
2012-10-28 19:12   ` [PATCH 4/5] mm, highmem: makes flush_all_zero_pkmaps() return index of last flushed entry Joonsoo Kim
2012-10-29  2:06     ` Minchan Kim
2012-10-29 13:12       ` JoonSoo Kim
2012-10-28 19:12   ` [PATCH 5/5] mm, highmem: get virtual address of the page using PKMAP_ADDR() Joonsoo Kim
2012-10-29  2:09     ` Minchan Kim
2012-10-29  2:12   ` [PATCH 0/5] minor clean-up and optimize highmem related code Minchan Kim
2012-10-29 13:15     ` JoonSoo Kim
2012-10-31 17:11       ` JoonSoo Kim
2012-10-31 16:56 ` [PATCH v2 " Joonsoo Kim
2012-10-31 16:56   ` [PATCH v2 1/5] mm, highmem: use PKMAP_NR() to calculate an index of pkmap Joonsoo Kim
2012-10-31 16:56   ` [PATCH v2 2/5] mm, highmem: remove useless pool_lock Joonsoo Kim
2012-10-31 16:56   ` [PATCH v2 3/5] mm, highmem: remove page_address_pool list Joonsoo Kim
2012-10-31 16:56   ` [PATCH v2 4/5] mm, highmem: makes flush_all_zero_pkmaps() return index of first flushed entry Joonsoo Kim
2012-11-01  5:03     ` Minchan Kim
2012-11-02 19:07       ` JoonSoo Kim
2012-11-02 22:42         ` Minchan Kim
2012-11-13  0:30           ` JoonSoo Kim
2012-11-13 12:49             ` Minchan Kim
2012-11-13 14:12               ` JoonSoo Kim
2012-11-13 15:01                 ` Minchan Kim
2012-11-14 17:09                   ` JoonSoo Kim
2012-11-19 23:46                     ` Minchan Kim
2012-11-27 15:01                       ` JoonSoo Kim
2012-10-31 16:56   ` [PATCH v2 5/5] mm, highmem: get virtual address of the page using PKMAP_ADDR() Joonsoo Kim

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=20120903100855.GA11266@suse.de \
    --to=mgorman@suse.de \
    --cc=cl@linux-foundation.org \
    --cc=js1304@gmail.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=penberg@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;
as well as URLs for NNTP newsgroup(s).