Date: Thu, 15 Oct 2009 01:44:10 +0100 (BST)
From: Hugh Dickins <hugh.dickins@tiscali.co.uk>
To: Andrew Morton <akpm@linux-foundation.org>
cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>,
       linux-kernel@vger.kernel.org, linux-mm@kvack.org
Subject: [PATCH 0/9] swap_info and swap_map patches
Message-ID: <Pine.LNX.4.64.0910150130001.2250@sister.anvils>
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 1368
Lines: 32

Here's a series of nine patches around the swap_info_struct: against
2.6.32-rc4, but intended for mmotm, which is currently similar here.

They start out with some old and not very important cleanups, but get
around to solving the swap count overflow problem: our handling above
32765 has depended on hoping that it won't coincide with other races.

That problem exists in theory today (when pid_max is raised from its
default), though never reported in practice; but the motivation for
solving it now comes from the impending KSM swapping patches - it
becomes very easy for anyone to overflow the maximum that way.

But most people will never have a swap count overflow in their life:
the benefit for them is that the vmalloc'ed swap_map halves in size.

This is all internal housekeeping: no change to actual swapping and
page reclaim.

 include/linux/swap.h |   66 ++-
 mm/memory.c          |   19 
 mm/page_io.c         |   19 
 mm/rmap.c            |    6 
 mm/shmem.c           |   11 
 mm/swapfile.c        |  834 +++++++++++++++++++++++++----------------
 6 files changed, 599 insertions(+), 356 deletions(-)

Hugh
--
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/