[ 22/23] [Suspend2] Modify swsusp to thaw kernel threads while eating memory.

From: Nigel Cunningham
Date: Wed Jan 25 2006 - 22:50:01 EST



Modify swsusp so that while trying to eat memory, it allows kernel threads
to run. This avoids a deadlock that could otherwise occur if access to a
filesystem is needed while freeing the memory.

Signed-off-by: Nigel Cunningham <nigel@xxxxxxxxxxxx>

kernel/power/main.c | 4 ++++
kernel/power/swsusp.c | 3 +++
2 files changed, 7 insertions(+), 0 deletions(-)

diff --git a/kernel/power/main.c b/kernel/power/main.c
index 6f854e4..2fed3dc 100644
--- a/kernel/power/main.c
+++ b/kernel/power/main.c
@@ -72,6 +72,8 @@ static int suspend_prepare(suspend_state
goto Thaw;
}

+ thaw_processes(FREEZER_KERNEL_THREADS);
+
if ((free_pages = nr_free_pages()) < FREE_PAGE_NUMBER) {
pr_debug("PM: free some memory\n");
shrink_all_memory(FREE_PAGE_NUMBER - free_pages);
@@ -82,6 +84,8 @@ static int suspend_prepare(suspend_state
}
}

+ freeze_processes();
+
if (pm_ops->prepare) {
if ((error = pm_ops->prepare(state)))
goto Thaw;
diff --git a/kernel/power/swsusp.c b/kernel/power/swsusp.c
index 55a18d2..3bc835a 100644
--- a/kernel/power/swsusp.c
+++ b/kernel/power/swsusp.c
@@ -575,6 +575,8 @@ int swsusp_shrink_memory(void)
unsigned int i = 0;
char *p = "-\\|/";

+ thaw_processes(FREEZER_KERNEL_THREADS);
+
printk("Shrinking memory... ");
do {
size = 2 * count_highmem_pages();
@@ -598,6 +600,7 @@ int swsusp_shrink_memory(void)
} while (tmp > 0);
printk("\bdone (%lu pages freed)\n", pages);

+ freeze_processes();
return 0;
}


--
Nigel Cunningham nigel at suspend2 dot net
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