From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail138.messagelabs.com (mail138.messagelabs.com [216.82.249.35]) by kanga.kvack.org (Postfix) with ESMTP id 889AA6B016D for ; Tue, 9 Aug 2011 08:23:39 -0400 (EDT) Message-Id: <4E414320020000780005057E@nat28.tlf.novell.com> Date: Tue, 09 Aug 2011 13:24:32 +0100 From: "Jan Beulich" Subject: Re: Subject: [PATCH V6 1/4] mm: frontswap: swap data structure changes References: <20110808204555.GA15850@ca-server1.us.oracle.com> In-Reply-To: <20110808204555.GA15850@ca-server1.us.oracle.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable Content-Disposition: inline Sender: owner-linux-mm@kvack.org List-ID: To: Dan Magenheimer Cc: hannes@cmpxchg.org, jackdachef@gmail.com, hughd@google.com, jeremy@goop.org, npiggin@kernel.dk, linux-mm@kvack.org, akpm@linux-foundation.org, sjenning@linux.vnet.ibm.com, chris.mason@oracle.com, konrad.wilk@oracle.com, kurt.hackel@oracle.com, riel@redhat.com, ngupta@vflare.org, linux-kernel@vger.kernel.org, matthew@wil.cx >>> On 08.08.11 at 22:45, Dan Magenheimer = wrote: > From: Dan Magenheimer > Subject: [PATCH V6 1/4] mm: frontswap: swap data structure changes >=20 > This first patch of four in the frontswap series makes available core > swap data structures (swap_lock, swap_list and swap_info) that are > needed by frontswap.c but we don't need to expose them to the dozens > of files that include swap.h so we create a new swapfile.h just to > extern-ify these. >=20 > Also add frontswap-related elements to swap_info_struct. Frontswap_map > points to vzalloc'ed one-bit-per-swap-page metadata that indicates > whether the swap page is in frontswap or in the device and frontswap_page= s > counts how many pages are in frontswap. We don't tie these to > CONFIG_FRONTSWAP to avoid unnecessary clutter around various frontswap > hooks. >=20 > [v6: rebase to 3.0-rc1] > [v5: no change from v4] > [v4: rebase to 2.6.39] > Signed-off-by: Dan Magenheimer > Reviewed-by: Konrad Wilk > Acked-by: Seth Jennings > Cc: Jeremy Fitzhardinge > Cc: Hugh Dickins > Cc: Johannes Weiner > Cc: Nitin Gupta > Cc: Matthew Wilcox > Cc: Chris Mason > Cc: Jan Beulich > Cc: Rik Riel > Cc: Andrew Morton >=20 > --- linux/include/linux/swapfile.h 1969-12-31 17:00:00.000000000 = -0700 > +++ frontswap/include/linux/swapfile.h 2011-08-08 08:59:03.9516945= 06 -0600 > @@ -0,0 +1,13 @@ > +#ifndef _LINUX_SWAPFILE_H > +#define _LINUX_SWAPFILE_H > + > +/* > + * these were static in swapfile.c but frontswap.c needs them and we = don't > + * want to expose them to the dozens of source files that include = swap.h > + */ > +extern spinlock_t swap_lock; > +extern struct swap_list_t swap_list; > +extern struct swap_info_struct *swap_info[]; > +extern int try_to_unuse(unsigned int, bool, unsigned long); > + > +#endif /* _LINUX_SWAPFILE_H */ > --- linux/include/linux/swap.h 2011-08-08 08:19:25.880690134 = -0600 > +++ frontswap/include/linux/swap.h 2011-08-08 08:59:03.952691415 = -0600 > @@ -194,6 +194,8 @@ struct swap_info_struct { > struct block_device *bdev; /* swap device or bdev of swap = file */ > struct file *swap_file; /* seldom referenced */ > unsigned int old_block_size; /* seldom referenced */ #ifdef CONFIG_FRONTSWAP > + unsigned long *frontswap_map; /* frontswap in-use, one bit per = page */ > + unsigned int frontswap_pages; /* frontswap pages in-use counter = */ #endif (to eliminate any overhead with that config option unset) Jan > }; > =20 > struct swap_list_t { -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org