[24/25] Merge pmdisk and swsusp
From: Patrick Mochel
Date: Sat Jul 17 2004 - 18:27:14 EST
ChangeSet 1.1866, 2004/07/17 14:09:36-07:00, mochel@xxxxxxxxxxxxxxxxxx
[Power Mgmt] Merge swsusp entry points with the PM core.
- Add {enable,disable}_nonboot_cpus() to prepare() and finish() in
kernel/power/disk.c
- Move swsusp __setup options there. Remove resume_status variable in favor
of simpler 'noresume' variable, and check it in pm_resume().
- Remove software_resume() from swsusp; rename pm_resume() to software_resume().
The latter is considerably cleaner, and leverages the core code.
- Move software_suspend() to kernel/power/main.c and shrink it down a
wrapper that takes pm_sem and calls pm_suspend_disk(), which does the
same as the old software_suspend() did.
This keeps the same entry points (via ACPI sleep and the reboot() syscall),
but actually allows those to use the low-level power states of the system
rather than always shutting off the system.
- Remove now-unused functions from swsusp.
include/linux/suspend.h | 1
kernel/power/disk.c | 49 ++++++++---
kernel/power/main.c | 15 +++
kernel/power/swsusp.c | 200 ------------------------------------------------
4 files changed, 52 insertions(+), 213 deletions(-)
diff -Nru a/include/linux/suspend.h b/include/linux/suspend.h
--- a/include/linux/suspend.h 2004-07-17 14:50:25 -07:00
+++ b/include/linux/suspend.h 2004-07-17 14:50:25 -07:00
@@ -41,7 +41,6 @@
printk("Warning: fake suspend called\n");
return -EPERM;
}
-#define software_resume() do { } while(0)
#endif /* CONFIG_SOFTWARE_SUSPEND */
diff -Nru a/kernel/power/disk.c b/kernel/power/disk.c
--- a/kernel/power/disk.c 2004-07-17 14:50:25 -07:00
+++ b/kernel/power/disk.c 2004-07-17 14:50:25 -07:00
@@ -30,6 +30,9 @@
extern int swsusp_free(void);
+static int noresume = 0;
+char resume_file[256] = CONFIG_PM_STD_PARTITION;
+
/**
* power_down - Shut machine down for hibernate.
* @mode: Suspend-to-disk mode
@@ -99,6 +102,7 @@
{
device_resume();
platform_finish();
+ enable_nonboot_cpus();
thaw_processes();
pm_restore_console();
}
@@ -126,6 +130,7 @@
/* Free memory before shutting down devices. */
free_some_memory();
+ disable_nonboot_cpus();
if ((error = device_suspend(PM_SUSPEND_DISK)))
goto Finish;
@@ -133,6 +138,7 @@
Finish:
platform_finish();
Thaw:
+ enable_nonboot_cpus();
thaw_processes();
pm_restore_console();
return error;
@@ -188,7 +194,7 @@
/**
- * pm_resume - Resume from a saved image.
+ * software_resume - Resume from a saved image.
*
* Called as a late_initcall (so all devices are discovered and
* initialized), we call pmdisk to see if we have a saved image or not.
@@ -199,10 +205,18 @@
*
*/
-static int pm_resume(void)
+static int software_resume(void)
{
int error;
+ if (noresume) {
+ /**
+ * FIXME: If noresume is specified, we need to find the partition
+ * and reset it back to normal swap space.
+ */
+ return 0;
+ }
+
pr_debug("PM: Reading pmdisk image.\n");
if ((error = swsusp_read()))
@@ -216,16 +230,6 @@
barrier();
mb();
- /* FIXME: The following (comment and mdelay()) are from swsusp.
- * Are they really necessary?
- *
- * We do not want some readahead with DMA to corrupt our memory, right?
- * Do it with disabled interrupts for best effect. That way, if some
- * driver scheduled DMA, we have good chance for DMA to finish ;-).
- */
- pr_debug("PM: Waiting for DMAs to settle down.\n");
- mdelay(1000);
-
pr_debug("PM: Restoring saved image.\n");
swsusp_resume();
pr_debug("PM: Restore failed, recovering.n");
@@ -237,7 +241,7 @@
return 0;
}
-late_initcall(pm_resume);
+late_initcall(software_resume);
static char * pm_disk_modes[] = {
@@ -336,3 +340,22 @@
}
core_initcall(pm_disk_init);
+
+
+static int __init resume_setup(char *str)
+{
+ if (noresume)
+ return 1;
+
+ strncpy( resume_file, str, 255 );
+ return 1;
+}
+
+static int __init noresume_setup(char *str)
+{
+ noresume = 1;
+ return 1;
+}
+
+__setup("noresume", noresume_setup);
+__setup("resume=", resume_setup);
diff -Nru a/kernel/power/main.c b/kernel/power/main.c
--- a/kernel/power/main.c 2004-07-17 14:50:25 -07:00
+++ b/kernel/power/main.c 2004-07-17 14:50:25 -07:00
@@ -169,6 +169,21 @@
return error;
}
+/*
+ * This is main interface to the outside world. It needs to be
+ * called from process context.
+ */
+int software_suspend(void)
+{
+ int error;
+
+ if (down_trylock(&pm_sem))
+ return -EBUSY;
+ error = pm_suspend_disk();
+ up(&pm_sem);
+ return error;
+}
+
/**
* pm_suspend - Externally visible function for suspending system.
diff -Nru a/kernel/power/swsusp.c b/kernel/power/swsusp.c
--- a/kernel/power/swsusp.c 2004-07-17 14:50:25 -07:00
+++ b/kernel/power/swsusp.c 2004-07-17 14:50:25 -07:00
@@ -71,11 +71,6 @@
#include "power.h"
-unsigned char software_suspend_enabled = 0;
-
-#define NORESUME 1
-#define RESUME_SPECIFIED 2
-
/* References to section boundaries */
extern char __nosave_begin, __nosave_end;
@@ -85,8 +80,7 @@
int pagedir_order_check;
int nr_copy_pages_check;
-static int resume_status;
-static char resume_file[256] = CONFIG_PM_STD_PARTITION;
+extern char resume_file[];
static dev_t resume_device;
/* Local variables that should not be affected by save */
unsigned int nr_copy_pages __nosavedata = 0;
@@ -664,30 +658,6 @@
free_pages(p, pagedir_order);
}
-static int prepare_suspend_processes(void)
-{
- sys_sync(); /* Syncing needs pdflushd, so do it before stopping processes */
- if (freeze_processes()) {
- printk( KERN_ERR "Suspend failed: Not all processes stopped!\n" );
- thaw_processes();
- return 1;
- }
- return 0;
-}
-
-/*
- * Try to free as much memory as possible, but do not OOM-kill anyone
- *
- * Notice: all userland should be stopped at this point, or livelock is possible.
- */
-static void free_some_memory(void)
-{
- printk("Freeing memory: ");
- while (shrink_all_memory(10000))
- printk(".");
- printk("|\n");
-}
-
static void calc_order(void)
{
@@ -878,48 +848,6 @@
}
-static void suspend_power_down(void)
-{
- extern int C_A_D;
- C_A_D = 0;
- printk(KERN_EMERG "%s%s Trying to power down.\n", name_suspend, TEST_SWSUSP ? "Disable TEST_SWSUSP. NOT ": "");
-#ifdef CONFIG_VT
- PRINTK(KERN_EMERG "shift_state: %04x\n", shift_state);
- mdelay(1000);
- if (TEST_SWSUSP ^ (!!(shift_state & (1 << KG_CTRL))))
- machine_restart(NULL);
- else
-#endif
- {
- device_suspend(3);
- device_shutdown();
- machine_power_off();
- }
-
- printk(KERN_EMERG "%sProbably not capable for powerdown. System halted.\n", name_suspend);
- machine_halt();
- while (1);
- /* NOTREACHED */
-}
-
-
-static void suspend_finish(void)
-{
- free_pages((unsigned long) pagedir_nosave, pagedir_order);
-
-#ifdef CONFIG_HIGHMEM
- printk( "Restoring highmem\n" );
- restore_highmem();
-#endif
- device_resume();
-
-#ifdef SUSPEND_CONSOLE
- acquire_console_sem();
- update_screen(fg_console);
- release_console_sem();
-#endif
-}
-
extern asmlinkage int swsusp_arch_suspend(void);
extern asmlinkage int swsusp_arch_resume(void);
@@ -971,59 +899,6 @@
-static int in_suspend __nosavedata = 0;
-
-/*
- * This is main interface to the outside world. It needs to be
- * called from process context.
- */
-int software_suspend(void)
-{
- int res;
- if (!software_suspend_enabled)
- return -EAGAIN;
-
- software_suspend_enabled = 0;
- might_sleep();
-
- if (arch_prepare_suspend()) {
- printk("%sArchitecture failed to prepare\n", name_suspend);
- return -EPERM;
- }
- if (pm_prepare_console())
- printk( "%sCan't allocate a console... proceeding\n", name_suspend);
- if (!prepare_suspend_processes()) {
-
- /* At this point, all user processes and "dangerous"
- kernel threads are stopped. Free some memory, as we
- need half of memory free. */
-
- free_some_memory();
- disable_nonboot_cpus();
- /* Save state of all device drivers, and stop them. */
- printk("Suspending devices... ");
- if ((res = device_suspend(3))==0) {
- in_suspend = 1;
-
- res = swsusp_save();
-
- if (!res && in_suspend) {
- swsusp_write();
- suspend_power_down();
- }
- in_suspend = 0;
- suspend_finish();
- }
- thaw_processes();
- enable_nonboot_cpus();
- } else
- res = -EBUSY;
- software_suspend_enabled = 1;
- MDELAY(1000);
- pm_restore_console();
- return res;
-}
-
/* More restore stuff */
#define does_collide(addr) does_collide_order(pagedir_nosave, addr, 0)
@@ -1370,76 +1245,3 @@
pr_debug("pmdisk: Error %d resuming\n", error);
return error;
}
-
-/**
- * software_resume - Resume from a saved image.
- *
- * Called as a late_initcall (so all devices are discovered and
- * initialized), we call swsusp to see if we have a saved image or not.
- * If so, we quiesce devices, then restore the saved image. We will
- * return above (in pm_suspend_disk() ) if everything goes well.
- * Otherwise, we fail gracefully and return to the normally
- * scheduled program.
- *
- */
-static int __init software_resume(void)
-{
- if (num_online_cpus() > 1) {
- printk(KERN_WARNING "Software Suspend has malfunctioning SMP support. Disabled :(\n");
- return -EINVAL;
- }
- /* We enable the possibility of machine suspend */
- software_suspend_enabled = 1;
- if (!resume_status)
- return 0;
-
- printk( "%s", name_resume );
- if (resume_status == NORESUME) {
- /*
- * FIXME: If noresume is specified, we need to handle by finding
- * the right partition and resettting the signature.
- */
- return 0;
- }
- MDELAY(1000);
-
- if (pm_prepare_console())
- printk("swsusp: Can't allocate a console... proceeding\n");
-
- if (swsusp_read())
- goto read_failure;
- /* FIXME: Should we stop processes here, just to be safer? */
- disable_nonboot_cpus();
- device_suspend(3);
- swsusp_resume();
- panic("This never returns");
-
-read_failure:
- pm_restore_console();
- return 0;
-}
-
-late_initcall(software_resume);
-
-static int __init resume_setup(char *str)
-{
- if (resume_status == NORESUME)
- return 1;
-
- strncpy( resume_file, str, 255 );
- resume_status = RESUME_SPECIFIED;
-
- return 1;
-}
-
-static int __init noresume_setup(char *str)
-{
- resume_status = NORESUME;
- return 1;
-}
-
-__setup("noresume", noresume_setup);
-__setup("resume=", resume_setup);
-
-EXPORT_SYMBOL(software_suspend);
-EXPORT_SYMBOL(software_suspend_enabled);
-
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