From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932357AbVJQWls (ORCPT ); Mon, 17 Oct 2005 18:41:48 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932354AbVJQWl1 (ORCPT ); Mon, 17 Oct 2005 18:41:27 -0400 Received: from anf141.internetdsl.tpnet.pl ([83.17.87.141]:34243 "EHLO anf141.internetdsl.tpnet.pl") by vger.kernel.org with ESMTP id S932359AbVJQWky (ORCPT ); Mon, 17 Oct 2005 18:40:54 -0400 From: "Rafael J. Wysocki" To: Pavel Machek Subject: [PATCH 4/4] swsusp: reduce the use of global variables Date: Tue, 18 Oct 2005 00:13:18 +0200 User-Agent: KMail/1.8.2 Cc: LKML , Andrew Morton References: <200510172336.53194.rjw@sisk.pl> In-Reply-To: <200510172336.53194.rjw@sisk.pl> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-2" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200510180013.18967.rjw@sisk.pl> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org The following patch reduces the use of global variables in the snapshot-handling part of swsusp, snapshot.c. Signed-off-by: Rafael J. Wysocki Index: linux-2.6.14-rc4-mm1/kernel/power/snapshot.c =================================================================== --- linux-2.6.14-rc4-mm1.orig/kernel/power/snapshot.c 2005-10-17 23:28:40.000000000 +0200 +++ linux-2.6.14-rc4-mm1/kernel/power/snapshot.c 2005-10-18 00:13:02.000000000 +0200 @@ -164,37 +164,38 @@ return 1; } -static void count_data_pages(void) +static unsigned count_data_pages(void) { struct zone *zone; unsigned long zone_pfn; + unsigned n; - nr_copy_pages = 0; - + n = 0; for_each_zone (zone) { if (is_highmem(zone)) continue; mark_free_pages(zone); for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn) - nr_copy_pages += saveable(zone, &zone_pfn); + n += saveable(zone, &zone_pfn); } + return n; } -static void copy_data_pages(void) +static void copy_data_pages(struct pbe *pblist) { struct zone *zone; unsigned long zone_pfn; - struct pbe *pbe = pagedir_nosave, *p; + struct pbe *pbe, *p; - pr_debug("copy_data_pages(): pages to copy: %d\n", nr_copy_pages); + pbe = pblist; for_each_zone (zone) { if (is_highmem(zone)) continue; mark_free_pages(zone); /* This is necessary for swsusp_free() */ - for_each_pb_page (p, pagedir_nosave) + for_each_pb_page (p, pblist) SetPageNosaveFree(virt_to_page(p)); - for_each_pbe (p, pagedir_nosave) + for_each_pbe (p, pblist) SetPageNosaveFree(virt_to_page(p->address)); for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn) { if (saveable(zone, &zone_pfn)) { @@ -347,46 +348,39 @@ * free pages. */ -static int enough_free_mem(void) +static int enough_free_mem(unsigned nr_pages) { pr_debug("swsusp: available memory: %u pages\n", nr_free_pages()); - return nr_free_pages() > (nr_copy_pages + PAGES_FOR_IO + - nr_copy_pages/PBES_PER_PAGE + !!(nr_copy_pages%PBES_PER_PAGE)); + return nr_free_pages() > (nr_pages + PAGES_FOR_IO + + (nr_pages + PBES_PER_PAGE - 1) / PBES_PER_PAGE); } -static int swsusp_alloc(void) +static struct pbe *swsusp_alloc(unsigned nr_pages) { - struct pbe *p; + struct pbe *pblist, *p; - pagedir_nosave = NULL; - - if (MAX_PBES < nr_copy_pages / PBES_PER_PAGE + - !!(nr_copy_pages % PBES_PER_PAGE)) - return -ENOSPC; - - if (!(pagedir_save = alloc_pagedir(nr_copy_pages))) { + if (!(pblist = alloc_pagedir(nr_pages))) { printk(KERN_ERR "suspend: Allocating pagedir failed.\n"); - return -ENOMEM; + return NULL; } - create_pbe_list(pagedir_save, nr_copy_pages); - pagedir_nosave = pagedir_save; + create_pbe_list(pblist, nr_pages); - for_each_pbe (p, pagedir_save) { + for_each_pbe (p, pblist) { p->address = (unsigned long)alloc_image_page(); if (!p->address) { printk(KERN_ERR "suspend: Allocating image pages failed.\n"); swsusp_free(); - return -ENOMEM; + return NULL; } } - return 0; + return pblist; } int swsusp_save(void) { - int error; + unsigned nr_pages; pr_debug("swsusp: critical section: \n"); if (save_highmem()) { @@ -396,33 +390,37 @@ } drain_local_pages(); - count_data_pages(); - printk("swsusp: Need to copy %u pages\n", nr_copy_pages); + nr_pages = count_data_pages(); + printk("swsusp: Need to copy %u pages\n", nr_pages); pr_debug("swsusp: pages needed: %u + %lu + %u, free: %u\n", - nr_copy_pages, - nr_copy_pages/PBES_PER_PAGE + !!(nr_copy_pages%PBES_PER_PAGE), + nr_pages, + (nr_pages + PBES_PER_PAGE - 1) / PBES_PER_PAGE, PAGES_FOR_IO, nr_free_pages()); - if (!enough_free_mem()) { + /* This is needed because of the fixed size of swsusp_info */ + if (MAX_PBES < (nr_pages + PBES_PER_PAGE - 1) / PBES_PER_PAGE) + return -ENOSPC; + + if (!enough_free_mem(nr_pages)) { printk(KERN_ERR "swsusp: Not enough free memory\n"); return -ENOMEM; } - if (!enough_swap()) { + if (!enough_swap(nr_pages)) { printk(KERN_ERR "swsusp: Not enough free swap\n"); return -ENOSPC; } - error = swsusp_alloc(); - if (error) - return error; + pagedir_nosave = swsusp_alloc(nr_pages); + if (!pagedir_nosave) + return -ENOMEM; /* During allocating of suspend pagedir, new cold pages may appear. * Kill them. */ drain_local_pages(); - copy_data_pages(); + copy_data_pages(pagedir_nosave); /* * End of critical section. From now on, we can write to memory, @@ -430,6 +428,8 @@ * touch swap space! Except we must write out our image of course. */ - printk("swsusp: critical section/: done (%d pages copied)\n", nr_copy_pages ); + nr_copy_pages = nr_pages; + + printk("swsusp: critical section/: done (%d pages copied)\n", nr_pages); return 0; } Index: linux-2.6.14-rc4-mm1/kernel/power/swsusp.c =================================================================== --- linux-2.6.14-rc4-mm1.orig/kernel/power/swsusp.c 2005-10-17 23:28:52.000000000 +0200 +++ linux-2.6.14-rc4-mm1/kernel/power/swsusp.c 2005-10-18 00:13:02.000000000 +0200 @@ -543,14 +543,14 @@ * We should only consider resume_device. */ -int enough_swap(void) +int enough_swap(unsigned nr_pages) { struct sysinfo i; si_swapinfo(&i); pr_debug("swsusp: available swap: %lu pages\n", i.freeswap); - return i.freeswap > (nr_copy_pages + PAGES_FOR_IO + - nr_copy_pages/PBES_PER_PAGE + !!(nr_copy_pages%PBES_PER_PAGE)); + return i.freeswap > (nr_pages + PAGES_FOR_IO + + (nr_pages + PBES_PER_PAGE - 1) / PBES_PER_PAGE); } Index: linux-2.6.14-rc4-mm1/kernel/power/power.h =================================================================== --- linux-2.6.14-rc4-mm1.orig/kernel/power/power.h 2005-10-17 23:28:29.000000000 +0200 +++ linux-2.6.14-rc4-mm1/kernel/power/power.h 2005-10-18 00:13:02.000000000 +0200 @@ -69,4 +69,4 @@ extern struct pbe * alloc_pagedir(unsigned nr_pages); extern void create_pbe_list(struct pbe *pblist, unsigned nr_pages); extern void swsusp_free(void); -extern int enough_swap(void); +extern int enough_swap(unsigned nr_pages);