[please test] 2.6.10-rc3 swsusp speedups

From: Pavel Machek
Date: Tue Dec 07 2004 - 06:04:38 EST

Hi!

This should fix O(n^2) behaviour in current swsusp, making "it thinks
for 2 minutes before saving image" go away. It should not break
anything. I'd like as many people as possible test it, because I'll
try to push this into 2.6.11....

Apply with -p0, sorry. [How do I generate nicer patch with CVS?]
Pavel

--- arch/i386/kernel/signal.c 22 Nov 2004 17:47:28 -0000 1.50
+++ arch/i386/kernel/signal.c 6 Dec 2004 15:19:35 -0000
@@ -602,7 +602,8 @@

if (current->flags & PF_FREEZE) {
refrigerator(0);
- goto no_signal;
+ if (!signal_pending(current))
+ goto no_signal;
}

if (!oldset)
--- arch/i386/kernel/acpi/wakeup.S 19 Oct 2004 06:03:51 -0000 1.8
+++ arch/i386/kernel/acpi/wakeup.S 20 Oct 2004 18:01:03 -0000
@@ -278,7 +278,7 @@
movl %edi, saved_context_edi
pushfl ; popl saved_context_eflags

- movl $ret_point,saved_eip
+ movl $ret_point, saved_eip
ret


@@ -295,7 +295,7 @@
call save_registers
pushl $3
call acpi_enter_sleep_state
- addl $4,%esp
+ addl $4, %esp
ret
.p2align 4,,7
ret_point:
--- include/linux/page-flags.h 24 Aug 2004 18:26:54 -0000 1.58
+++ include/linux/page-flags.h 20 Oct 2004 17:53:42 -0000
@@ -74,7 +74,7 @@
#define PG_swapcache 16 /* Swap page: swp_entry_t in private */
#define PG_mappedtodisk 17 /* Has blocks allocated on-disk */
#define PG_reclaim 18 /* To be reclaimed asap */
-
+#define PG_nosave_free 19 /* Page is free and should not be written */

/*
* Global page accounting. One instance per CPU. Only unsigned longs are
@@ -277,6 +277,10 @@
#define ClearPageNosave(page) clear_bit(PG_nosave, &(page)->flags)
#define TestClearPageNosave(page) test_and_clear_bit(PG_nosave, &(page)->flags)

+#define PageNosaveFree(page) test_bit(PG_nosave_free, &(page)->flags)
+#define SetPageNosaveFree(page) set_bit(PG_nosave_free, &(page)->flags)
+#define ClearPageNosaveFree(page) clear_bit(PG_nosave_free, &(page)->flags)
+
#define PageMappedToDisk(page) test_bit(PG_mappedtodisk, &(page)->flags)
#define SetPageMappedToDisk(page) set_bit(PG_mappedtodisk, &(page)->flags)
#define ClearPageMappedToDisk(page) clear_bit(PG_mappedtodisk, &(page)->flags)
--- include/linux/suspend.h 29 Sep 2004 20:04:50 -0000 1.26
+++ include/linux/suspend.h 20 Oct 2004 17:53:42 -0000
@@ -31,6 +31,7 @@

/* mm/page_alloc.c */
extern void drain_local_pages(void);
+extern void mark_free_pages(struct zone *zone);

/* kernel/power/swsusp.c */
extern int software_suspend(void);
@@ -54,6 +55,8 @@

#else
static inline void refrigerator(unsigned long flag) {}
+static inline int freeze_processes(void) { BUG(); }
+static inline void thaw_processes(void) {}
#endif /* CONFIG_PM */

#ifdef CONFIG_SMP
--- kernel/signal.c 29 Oct 2004 21:53:12 -0000 1.148
+++ kernel/signal.c 4 Nov 2004 00:04:04 -0000
@@ -1442,8 +1442,7 @@
unsigned long flags;
struct sighand_struct *psig;

- if (sig == -1)
- BUG();
+ BUG_ON(sig == -1);

/* do_notify_parent_cldstop should have been called instead. */
BUG_ON(tsk->state & (TASK_STOPPED|TASK_TRACED));
--- kernel/sys.c 3 Dec 2004 15:46:44 -0000 1.100
+++ kernel/sys.c 7 Dec 2004 10:41:13 -0000
@@ -401,6 +401,7 @@
case LINUX_REBOOT_CMD_HALT:
notifier_call_chain(&reboot_notifier_list, SYS_HALT, NULL);
system_state = SYSTEM_HALT;
+ device_suspend(3);
device_shutdown();
printk(KERN_EMERG "System halted.\n");
machine_halt();
@@ -411,6 +412,7 @@
case LINUX_REBOOT_CMD_POWER_OFF:
notifier_call_chain(&reboot_notifier_list, SYS_POWER_OFF, NULL);
system_state = SYSTEM_POWER_OFF;
+ device_suspend(3);
device_shutdown();
printk(KERN_EMERG "Power down.\n");
machine_power_off();
@@ -427,6 +429,7 @@

notifier_call_chain(&reboot_notifier_list, SYS_RESTART, buffer);
system_state = SYSTEM_RESTART;
+ device_suspend(3);
device_shutdown();
printk(KERN_EMERG "Restarting system with command '%s'.\n", buffer);
machine_restart(buffer);
--- kernel/power/disk.c 29 Oct 2004 20:20:47 -0000 1.10
+++ kernel/power/disk.c 16 Nov 2004 12:39:00 -0000
@@ -43,7 +43,7 @@
* there ain't no turning back.
*/

-static void power_down(u32 mode)
+static void power_down(suspend_disk_method_t mode)
{
unsigned long flags;
int error = 0;
--- kernel/power/main.c 29 Oct 2004 20:20:47 -0000 1.7
+++ kernel/power/main.c 16 Nov 2004 12:47:53 -0000
@@ -65,7 +65,11 @@
goto Thaw;
}

- if ((error = device_suspend(state)))
+ /* FIXME: this is suspend confusion biting us. If we pass
+ state, we'll pass 2 in suspend-to-RAM case; EHCI will
+ actually break suspend, because it interprets 2 as PCI_D2
+ state. Oops. */
+ if ((error = device_suspend(3)))
goto Finish;
return 0;
Finish:
@@ -78,13 +82,14 @@
}


-static int suspend_enter(u32 state)
+static int suspend_enter(suspend_state_t state)
{
int error = 0;
unsigned long flags;

local_irq_save(flags);
- if ((error = device_power_down(state)))
+ /* FIXME: see suspend_prepare */
+ if ((error = device_power_down(3)))
goto Done;
error = pm_ops->enter(state);
device_power_up();
@@ -230,8 +235,8 @@
p = memchr(buf, '\n', n);
len = p ? p - buf : n;

- for (s = &pm_states[state]; state < PM_SUSPEND_MAX; s++, state++) {
- if (*s && !strncmp(buf, *s, len))
+ for (s = &pm_states[state]; *s; s++, state++) {
+ if (!strncmp(buf, *s, len))
break;
}
if (*s)
--- kernel/power/swsusp.c 28 Oct 2004 15:21:34 -0000 1.29
+++ kernel/power/swsusp.c 4 Nov 2004 00:04:06 -0000
@@ -74,11 +74,9 @@
/* References to section boundaries */
extern char __nosave_begin, __nosave_end;

-extern int is_head_of_free_region(struct page *);
-
/* Variables to be preserved over suspend */
-int pagedir_order_check;
-int nr_copy_pages_check;
+static int pagedir_order_check;
+static int nr_copy_pages_check;

extern char resume_file[];
static dev_t resume_device;
@@ -426,12 +424,12 @@
static int save_highmem_zone(struct zone *zone)
{
unsigned long zone_pfn;
+ mark_free_pages(zone);
for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn) {
struct page *page;
struct highmem_page *save;
void *kaddr;
unsigned long pfn = zone_pfn + zone->zone_start_pfn;
- int chunk_size;

if (!(pfn%1000))
printk(".");
@@ -448,11 +446,9 @@
printk("highmem reserved page?!\n");
continue;
}
- if ((chunk_size = is_head_of_free_region(page))) {
- pfn += chunk_size - 1;
- zone_pfn += chunk_size - 1;
+ BUG_ON(PageNosave(page));
+ if (PageNosaveFree(page))
continue;
- }
save = kmalloc(sizeof(struct highmem_page), GFP_ATOMIC);
if (!save)
return -ENOMEM;
@@ -524,21 +520,16 @@
* We save a page if it's Reserved, and not in the range of pages
* statically defined as 'unsaveable', or if it isn't reserved, and
* isn't part of a free chunk of pages.
- * If it is part of a free chunk, we update @pfn to point to the last
- * page of the chunk.
*/

static int saveable(struct zone * zone, unsigned long * zone_pfn)
{
unsigned long pfn = *zone_pfn + zone->zone_start_pfn;
- unsigned long chunk_size;
struct page * page;

if (!pfn_valid(pfn))
return 0;

- if (!(pfn%1000))
- printk(".");
page = pfn_to_page(pfn);
BUG_ON(PageReserved(page) && PageNosave(page));
if (PageNosave(page))
@@ -547,10 +538,8 @@
pr_debug("[nosave pfn 0x%lx]", pfn);
return 0;
}
- if ((chunk_size = is_head_of_free_region(page))) {
- *zone_pfn += chunk_size - 1;
+ if (PageNosaveFree(page))
return 0;
- }

return 1;
}
@@ -563,10 +552,11 @@
nr_copy_pages = 0;

for_each_zone(zone) {
- if (!is_highmem(zone)) {
- for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn)
- nr_copy_pages += saveable(zone, &zone_pfn);
- }
+ 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);
}
}

@@ -576,52 +566,25 @@
struct zone *zone;
unsigned long zone_pfn;
struct pbe * pbe = pagedir_nosave;
+ int to_copy = nr_copy_pages;

for_each_zone(zone) {
- if (!is_highmem(zone))
- for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn) {
- if (saveable(zone, &zone_pfn)) {
- struct page * page;
- page = pfn_to_page(zone_pfn + zone->zone_start_pfn);
- pbe->orig_address = (long) page_address(page);
- /* copy_page is no usable for copying task structs. */
- memcpy((void *)pbe->address, (void *)pbe->orig_address, PAGE_SIZE);
- pbe++;
- }
- }
- }
-}
-
-
-static void free_suspend_pagedir_zone(struct zone *zone, unsigned long pagedir)
-{
- unsigned long zone_pfn, pagedir_end, pagedir_pfn, pagedir_end_pfn;
- pagedir_end = pagedir + (PAGE_SIZE << pagedir_order);
- pagedir_pfn = __pa(pagedir) >> PAGE_SHIFT;
- pagedir_end_pfn = __pa(pagedir_end) >> PAGE_SHIFT;
- for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn) {
- struct page *page;
- unsigned long pfn = zone_pfn + zone->zone_start_pfn;
- if (!pfn_valid(pfn))
- continue;
- page = pfn_to_page(pfn);
- if (!TestClearPageNosave(page))
- continue;
- else if (pfn >= pagedir_pfn && pfn < pagedir_end_pfn)
+ if (is_highmem(zone))
continue;
- __free_page(page);
- }
-}
-
-void swsusp_free(void)
-{
- unsigned long p = (unsigned long)pagedir_save;
- struct zone *zone;
- for_each_zone(zone) {
- if (!is_highmem(zone))
- free_suspend_pagedir_zone(zone, p);
+ mark_free_pages(zone);
+ for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn) {
+ if (saveable(zone, &zone_pfn)) {
+ struct page * page;
+ page = pfn_to_page(zone_pfn + zone->zone_start_pfn);
+ pbe->orig_address = (long) page_address(page);
+ /* copy_page is not usable for copying task structs. */
+ memcpy((void *)pbe->address, (void *)pbe->orig_address, PAGE_SIZE);
+ pbe++;
+ to_copy--;
+ }
+ }
}
- free_pages(p, pagedir_order);
+ BUG_ON(to_copy);
}


@@ -687,6 +650,24 @@
return 0;
}

+/**
+ * free_image_pages - Free pages allocated for snapshot
+ */
+
+static void free_image_pages(void)
+{
+ struct pbe * p;
+ int i;
+
+ p = pagedir_save;
+ for (i = 0, p = pagedir_save; i < nr_copy_pages; i++, p++) {
+ if (p->address) {
+ ClearPageNosave(virt_to_page(p->address));
+ free_page(p->address);
+ p->address = 0;
+ }
+ }
+}

/**
* alloc_image_pages - Allocate pages for the snapshot.
@@ -700,18 +681,19 @@

for (i = 0, p = pagedir_save; i < nr_copy_pages; i++, p++) {
p->address = get_zeroed_page(GFP_ATOMIC | __GFP_COLD);
- if(!p->address)
- goto Error;
+ if (!p->address)
+ return -ENOMEM;
SetPageNosave(virt_to_page(p->address));
}
return 0;
- Error:
- do {
- if (p->address)
- free_page(p->address);
- p->address = 0;
- } while (p-- > pagedir_save);
- return -ENOMEM;
+}
+
+void swsusp_free(void)
+{
+ BUG_ON(PageNosave(virt_to_page(pagedir_save)));
+ BUG_ON(PageNosaveFree(virt_to_page(pagedir_save)));
+ free_image_pages();
+ free_pages((unsigned long) pagedir_save, pagedir_order);
}


@@ -786,12 +768,13 @@

int suspend_prepare_image(void)
{
- unsigned int nr_needed_pages = 0;
+ unsigned int nr_needed_pages;
int error;

pr_debug("swsusp: critical section: \n");
if (save_highmem()) {
printk(KERN_CRIT "Suspend machine: Not enough free pages for highmem\n");
+ restore_highmem();
return -ENOMEM;
}

@@ -878,6 +861,7 @@

/* Even mappings of "global" things (vmalloc) need to be fixed */
__flush_tlb_global();
+ wbinvd(); /* Nigel says wbinvd here is good idea... */
return 0;
}

@@ -985,6 +969,8 @@
c = *c;
free_pages((unsigned long)f, pagedir_order);
}
+ if (ret)
+ return ret;
printk("|\n");
return check_pagedir();
}
@@ -1000,24 +986,14 @@

static atomic_t io_done = ATOMIC_INIT(0);

-static void start_io(void)
-{
- atomic_set(&io_done,1);
-}
-
static int end_io(struct bio * bio, unsigned int num, int err)
{
- atomic_set(&io_done,0);
+ if (!test_bit(BIO_UPTODATE, &bio->bi_flags))
+ panic("I/O error reading memory image");
+ atomic_set(&io_done, 0);
return 0;
}

-static void wait_io(void)
-{
- while(atomic_read(&io_done))
- io_schedule();
-}
-
-
static struct block_device * resume_bdev;

/**
@@ -1052,9 +1028,12 @@

if (rw == WRITE)
bio_set_pages_dirty(bio);
- start_io();
+
+ atomic_set(&io_done, 1);
submit_bio(rw | (1 << BIO_RW_SYNC), bio);
- wait_io();
+ while (atomic_read(&io_done))
+ yield();
+
Done:
bio_put(bio);
return error;
@@ -1110,6 +1089,7 @@
return -EPERM;
}
nr_copy_pages = swsusp_info.image_pages;
+ pagedir_order = get_bitmask_order(SUSPEND_PD_PAGES(nr_copy_pages));
return error;
}

@@ -1128,7 +1108,7 @@
*/
error = bio_write_page(0, &swsusp_header);
} else {
- pr_debug(KERN_ERR "swsusp: Invalid partition type.\n");
+ pr_debug(KERN_ERR "swsusp: Suspend partition has wrong signature?\n");
return -EINVAL;
}
if (!error)
@@ -1176,9 +1156,7 @@
int i, n = swsusp_info.pagedir_pages;
int error = 0;

- pagedir_order = get_bitmask_order(n);
-
- addr =__get_free_pages(GFP_ATOMIC, pagedir_order);
+ addr = __get_free_pages(GFP_ATOMIC, pagedir_order);
if (!addr)
return -ENOMEM;
pagedir_nosave = (struct pbe *)addr;
--- mm/page_alloc.c 16 Nov 2004 03:53:53 -0000 1.236
+++ mm/page_alloc.c 6 Dec 2004 15:23:18 -0000
@@ -437,26 +437,30 @@
#endif /* CONFIG_PM || CONFIG_HOTPLUG_CPU */

#ifdef CONFIG_PM
-int is_head_of_free_region(struct page *page)
+
+void mark_free_pages(struct zone *zone)
{
- struct zone *zone = page_zone(page);
- unsigned long flags;
+ unsigned long zone_pfn, flags;
int order;
struct list_head *curr;

- /*
- * Should not matter as we need quiescent system for
- * suspend anyway, but...
- */
+ if (!zone->spanned_pages)
+ return;
+
spin_lock_irqsave(&zone->lock, flags);
+ for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn)
+ ClearPageNosaveFree(pfn_to_page(zone_pfn + zone->zone_start_pfn));
+
for (order = MAX_ORDER - 1; order >= 0; --order)
- list_for_each(curr, &zone->free_area[order].free_list)
- if (page == list_entry(curr, struct page, lru)) {
- spin_unlock_irqrestore(&zone->lock, flags);
- return 1 << order;
- }
+ list_for_each(curr, &zone->free_area[order].free_list) {
+ unsigned long start_pfn, i;
+
+ start_pfn = page_to_pfn(list_entry(curr, struct page, lru));
+
+ for (i=0; i < (1<<order); i++)
+ SetPageNosaveFree(pfn_to_page(start_pfn+i));
+ }
spin_unlock_irqrestore(&zone->lock, flags);
- return 0;
}

/*
@@ -1581,7 +1585,7 @@
zone->zone_start_pfn = zone_start_pfn;

if ((zone_start_pfn) & (zone_required_alignment-1))
- printk("BUG: wrong zone alignment, it will crash\n");
+ printk(KERN_CRIT "BUG: wrong zone alignment, it will crash\n");

memmap_init(size, nid, j, zone_start_pfn);


--
People were complaining that M$ turns users into beta-testers...
...jr ghea gurz vagb qrirybcref, naq gurl frrz gb yvxr vg gung jnl!
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