[RFC][PATCH 1/6] swsusp: rework swsusp_suspend

From: Rafael J. Wysocki
Date: Sat Oct 29 2005 - 15:54:36 EST


This is a preliminary step. It makes only the functions in swsusp.c call
functions in snapshot.c and not both ways. Basically, it moves the code
without changing its functionality.

Signed-off-by: Rafael J. Wysocki <rjw@xxxxxxx>

kernel/power/power.h | 2 -
kernel/power/snapshot.c | 14 +---------
kernel/power/swsusp.c | 62 +++++++++++++++++++++++++++---------------------
3 files changed, 39 insertions(+), 39 deletions(-)

Index: linux-2.6.14-rc5-mm1/kernel/power/snapshot.c
===================================================================
--- linux-2.6.14-rc5-mm1.orig/kernel/power/snapshot.c 2005-10-28 23:46:36.000000000 +0200
+++ linux-2.6.14-rc5-mm1/kernel/power/snapshot.c 2005-10-28 23:49:15.000000000 +0200
@@ -89,7 +89,7 @@
}


-static int save_highmem(void)
+int save_highmem(void)
{
struct zone *zone;
int res = 0;
@@ -121,7 +121,7 @@
return 0;
}
#else
-static int save_highmem(void) { return 0; }
+int save_highmem(void) { return 0; }
int restore_highmem(void) { return 0; }
#endif /* CONFIG_HIGHMEM */

@@ -383,11 +383,6 @@
unsigned nr_pages;

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

drain_local_pages();
nr_pages = count_data_pages();
@@ -407,11 +402,6 @@
return -ENOMEM;
}

- if (!enough_swap(nr_pages)) {
- printk(KERN_ERR "swsusp: Not enough free swap\n");
- return -ENOSPC;
- }
-
pagedir_nosave = swsusp_alloc(nr_pages);
if (!pagedir_nosave)
return -ENOMEM;
Index: linux-2.6.14-rc5-mm1/kernel/power/swsusp.c
===================================================================
--- linux-2.6.14-rc5-mm1.orig/kernel/power/swsusp.c 2005-10-28 23:46:36.000000000 +0200
+++ linux-2.6.14-rc5-mm1/kernel/power/swsusp.c 2005-10-28 23:49:15.000000000 +0200
@@ -507,6 +507,26 @@
}

/**
+ * enough_swap - Make sure we have enough swap to save the image.
+ *
+ * Returns TRUE or FALSE after checking the total amount of swap
+ * space avaiable.
+ *
+ * FIXME: si_swapinfo(&i) returns all swap devices information.
+ * We should only consider resume_device.
+ */
+
+static int enough_swap(unsigned long nr_pages)
+{
+ struct sysinfo i;
+
+ si_swapinfo(&i);
+ pr_debug("swsusp: available swap: %lu pages\n", i.freeswap);
+ return i.freeswap > (nr_pages + PAGES_FOR_IO +
+ (nr_pages + PBES_PER_PAGE - 1) / PBES_PER_PAGE);
+}
+
+/**
* write_suspend_image - Write entire image and metadata.
*
*/
@@ -514,6 +534,11 @@
{
int error;

+ if (!enough_swap(nr_copy_pages)) {
+ printk(KERN_ERR "swsusp: Not enough free swap\n");
+ return -ENOSPC;
+ }
+
init_header();
if ((error = data_write()))
goto FreeData;
@@ -533,27 +558,6 @@
goto Done;
}

-/**
- * enough_swap - Make sure we have enough swap to save the image.
- *
- * Returns TRUE or FALSE after checking the total amount of swap
- * space avaiable.
- *
- * FIXME: si_swapinfo(&i) returns all swap devices information.
- * We should only consider resume_device.
- */
-
-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_pages + PAGES_FOR_IO +
- (nr_pages + PBES_PER_PAGE - 1) / PBES_PER_PAGE);
-}
-
-
/* It is important _NOT_ to umount filesystems at this point. We want
* them synced (in case something goes wrong) but we DO not want to mark
* filesystem clean: it is not. (And it does not matter, if we resume
@@ -576,6 +580,7 @@
int swsusp_suspend(void)
{
int error;
+
if ((error = arch_prepare_suspend()))
return error;
local_irq_disable();
@@ -587,15 +592,17 @@
*/
if ((error = device_power_down(PMSG_FREEZE))) {
printk(KERN_ERR "Some devices failed to power down, aborting suspend\n");
- local_irq_enable();
- return error;
+ goto Enable_irqs;
}

if ((error = swsusp_swap_check())) {
printk(KERN_ERR "swsusp: cannot find swap device, try swapon -a.\n");
- device_power_up();
- local_irq_enable();
- return error;
+ goto Power_up;
+ }
+
+ if ((error = save_highmem())) {
+ printk(KERN_ERR "swsusp: Not enough free pages for highmem\n");
+ goto Restore_highmem;
}

save_processor_state();
@@ -603,8 +610,11 @@
printk(KERN_ERR "Error %d suspending\n", error);
/* Restore control flow magically appears here */
restore_processor_state();
+Restore_highmem:
restore_highmem();
+Power_up:
device_power_up();
+Enable_irqs:
local_irq_enable();
return error;
}
Index: linux-2.6.14-rc5-mm1/kernel/power/power.h
===================================================================
--- linux-2.6.14-rc5-mm1.orig/kernel/power/power.h 2005-10-28 23:46:36.000000000 +0200
+++ linux-2.6.14-rc5-mm1/kernel/power/power.h 2005-10-28 23:49:15.000000000 +0200
@@ -65,8 +65,8 @@
extern asmlinkage int swsusp_arch_suspend(void);
extern asmlinkage int swsusp_arch_resume(void);

+extern int save_highmem(void);
extern int restore_highmem(void);
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(unsigned nr_pages);

-
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