Commit a0f49651 authored by Rafael J. Wysocki's avatar Rafael J. Wysocki Committed by Linus Torvalds
Browse files

[PATCH] swsusp: reduce the use of global variables 



Signed-off-by: default avatarRafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 25761b6e

kernel/power/power.h

+1 −1
Original line number Diff line number Diff line
@@ -69,4 +69,4 @@ extern int restore_highmem(void); 
extern void free_pagedir(struct pbe *pblist);

extern struct pbe * alloc_pagedir(unsigned nr_pages);

extern void create_pbe_list(struct pbe *pblist, unsigned nr_pages);

extern int enough_swap(void);
 
extern int enough_swap(unsigned nr_pages);

kernel/power/snapshot.c

+39 −39
Original line number Diff line number Diff line
@@ -187,37 +187,38 @@ static int saveable(struct zone * zone, unsigned long * zone_pfn) 
	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)) {
@@ -370,46 +371,39 @@ void swsusp_free(void) 
 *	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;



	pagedir_nosave = NULL;



	if (MAX_PBES < nr_copy_pages / PBES_PER_PAGE +

	    !!(nr_copy_pages % PBES_PER_PAGE))

		return -ENOSPC;

	struct pbe *pblist, *p;



	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;

}



static int suspend_prepare_image(void)

{

	int error;

	unsigned nr_pages;



	pr_debug("swsusp: critical section: \n");

	if (save_highmem()) {
@@ -419,33 +413,37 @@ static int suspend_prepare_image(void) 
	}



	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,
@@ -453,7 +451,9 @@ static int suspend_prepare_image(void) 
	 * 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;

}

kernel/power/swsusp.c

+3 −3
Original line number Diff line number Diff line
@@ -550,14 +550,14 @@ static int write_suspend_image(void) 
 *	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);

}