Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1161065AbVLJXCE (ORCPT ); Sat, 10 Dec 2005 18:02:04 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1161067AbVLJXCE (ORCPT ); Sat, 10 Dec 2005 18:02:04 -0500 Received: from gprs189-60.eurotel.cz ([160.218.189.60]:56456 "EHLO amd.ucw.cz") by vger.kernel.org with ESMTP id S1161065AbVLJXCB (ORCPT ); Sat, 10 Dec 2005 18:02:01 -0500 Date: Sun, 11 Dec 2005 00:01:34 +0100 From: Pavel Machek To: "Rafael J. Wysocki" Cc: Stefan Seyfried , LKML , Andy Isaacson Subject: Re: [RFC/RFT] swsusp: image size tunable (was: Re: [PATCH][mm] swsusp: limit image size) Message-ID: <20051210230134.GC5187@elf.ucw.cz> References: <200512072246.06222.rjw@sisk.pl> <20051210160641.GB5047@elf.ucw.cz> <200512102106.41952.rjw@sisk.pl> <200512102356.27271.rjw@sisk.pl> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200512102356.27271.rjw@sisk.pl> X-Warning: Reading this can be dangerous to your mental health. User-Agent: Mutt/1.5.9i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5713 Lines: 151 Hi! > > > > > The tunable may be useful to people who'd like to achieve the > > > > > maximum efficiency of suspend/resume and it would be a nice > > > > > feature to have, I think, but let's say we'll try to implement it > > > > > in the future, if still needed/wanted. > > > > > > > > Actually the tunable turned out to be quite easy to implement and I think > > > > I'll need it for userspace swsusp (the suspend-handling userspace > > > > process will need to tell the kernel how much space there is for the > > > > image). > > > > > > Looks mostly okay to me, small comments below. > > A cleaner version with comments etc. follows. Looks good to me. ACK. Pavel > Signed-off-by: Rafael J. Wysocki > > Documentation/power/interface.txt | 11 +++++++++++ > Documentation/power/swsusp.txt | 7 ++++++- > kernel/power/disk.c | 20 ++++++++++++++++++++ > kernel/power/power.h | 7 ++----- > kernel/power/swsusp.c | 10 +++++++++- > 5 files changed, 48 insertions(+), 7 deletions(-) > > Index: linux-2.6.15-rc5-mm1/kernel/power/disk.c > =================================================================== > --- linux-2.6.15-rc5-mm1.orig/kernel/power/disk.c 2005-12-07 23:19:03.000000000 +0100 > +++ linux-2.6.15-rc5-mm1/kernel/power/disk.c 2005-12-10 21:10:53.000000000 +0100 > @@ -367,9 +367,29 @@ > > power_attr(resume); > > +static ssize_t image_size_show(struct subsystem * subsys, char *buf) > +{ > + return sprintf(buf, "%u\n", image_size); > +} > + > +static ssize_t image_size_store(struct subsystem * subsys, const char * buf, size_t n) > +{ > + unsigned int size; > + > + if (sscanf(buf, "%u", &size) == 1) { > + image_size = size; > + return n; > + } > + > + return -EINVAL; > +} > + > +power_attr(image_size); > + > static struct attribute * g[] = { > &disk_attr.attr, > &resume_attr.attr, > + &image_size_attr.attr, > NULL, > }; > > Index: linux-2.6.15-rc5-mm1/kernel/power/power.h > =================================================================== > --- linux-2.6.15-rc5-mm1.orig/kernel/power/power.h 2005-12-10 20:59:52.000000000 +0100 > +++ linux-2.6.15-rc5-mm1/kernel/power/power.h 2005-12-10 21:13:04.000000000 +0100 > @@ -52,11 +52,8 @@ > extern unsigned int nr_copy_pages; > extern struct pbe *pagedir_nosave; > > -/* > - * Preferred image size in MB (set it to zero to get the smallest > - * image possible) > - */ > -#define IMAGE_SIZE 500 > +/* Preferred image size in MB (default 500) */ > +extern unsigned int image_size; > > extern asmlinkage int swsusp_arch_suspend(void); > extern asmlinkage int swsusp_arch_resume(void); > Index: linux-2.6.15-rc5-mm1/kernel/power/swsusp.c > =================================================================== > --- linux-2.6.15-rc5-mm1.orig/kernel/power/swsusp.c 2005-12-10 20:59:52.000000000 +0100 > +++ linux-2.6.15-rc5-mm1/kernel/power/swsusp.c 2005-12-10 22:21:25.000000000 +0100 > @@ -69,6 +69,14 @@ > > #include "power.h" > > +/* > + * Preferred image size in MB (tunable via /sys/power/image_size). > + * When it is set to N, swsusp will do its best to ensure the image > + * size will not exceed N MB, but if that is impossible, it will > + * try to create the smallest image possible. > + */ > +unsigned int image_size = 500; > + > #ifdef CONFIG_HIGHMEM > unsigned int count_highmem_pages(void); > int save_highmem(void); > @@ -647,7 +655,7 @@ > if (!tmp) > return -ENOMEM; > pages += tmp; > - } else if (size > (IMAGE_SIZE * 1024 * 1024) / PAGE_SIZE) { > + } else if (size > (image_size * 1024 * 1024) / PAGE_SIZE) { > tmp = shrink_all_memory(SHRINK_BITE); > pages += tmp; > } > Index: linux-2.6.15-rc5-mm1/Documentation/power/swsusp.txt > =================================================================== > --- linux-2.6.15-rc5-mm1.orig/Documentation/power/swsusp.txt 2005-10-28 02:02:08.000000000 +0200 > +++ linux-2.6.15-rc5-mm1/Documentation/power/swsusp.txt 2005-12-10 23:49:08.000000000 +0100 > @@ -27,6 +27,11 @@ > > echo platform > /sys/power/disk; echo disk > /sys/power/state > > +If you want to limit the suspend image size to N megabytes, do > + > +echo N > /sys/power/image_size > + > +before suspend (it is limited to 500 MB by default). > > Encrypted suspend image: > ------------------------ > Index: linux-2.6.15-rc5-mm1/Documentation/power/interface.txt > =================================================================== > --- linux-2.6.15-rc5-mm1.orig/Documentation/power/interface.txt 2005-10-28 02:02:08.000000000 +0200 > +++ linux-2.6.15-rc5-mm1/Documentation/power/interface.txt 2005-12-10 23:42:39.000000000 +0100 > @@ -41,3 +41,14 @@ > It will only change to 'firmware' or 'platform' if the system supports > it. > > +/sys/power/image_size controls the size of the image created by > +the suspend-to-disk mechanism. It can be written a string > +representing a non-negative integer that will be used as an upper > +limit of the image size, in megabytes. The suspend-to-disk mechanism will > +do its best to ensure the image size will not exceed that number. However, > +if this turns out to be impossible, it will try to suspend anyway using the > +smallest image possible. In particular, if "0" is written to this file, the > +suspend image will be as small as possible. > + > +Reading from this file will display the current image size limit, which > +is set to 500 MB by default. -- Thanks, Sharp! - 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/