From 232b14328050a4639130b0dec185f43968e72035 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Thu, 18 Oct 2007 03:04:44 -0700 Subject: [PATCH] freezer: do not sync filesystems from freeze_processes The syncing of filesystems from within the freezer is generally not needed. Also, if there's an ext3 filesystem loopback-mounted from a FUSE one, the syncing results in writes to it and deadlocks. Similarly, it will deadlock if FUSE implements sync. Change freeze_processes() so that it doesn't execute sys_sync() and make the suspend and hibernation code path sync filesystems independently of the freezer. Signed-off-by: Rafael J. Wysocki Acked-by: Pavel Machek Cc: Nigel Cunningham Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/power/disk.c | 4 ++++ kernel/power/main.c | 6 ++++++ kernel/power/process.c | 1 - kernel/power/user.c | 4 ++++ 4 files changed, 14 insertions(+), 1 deletion(-) diff --git a/kernel/power/disk.c b/kernel/power/disk.c index 9348d95a4fb..555c0f0b2f7 100644 --- a/kernel/power/disk.c +++ b/kernel/power/disk.c @@ -313,6 +313,10 @@ int hibernate(void) if (error) goto Exit; + printk("Syncing filesystems ... "); + sys_sync(); + printk("done.\n"); + error = prepare_processes(); if (error) goto Finish; diff --git a/kernel/power/main.c b/kernel/power/main.c index fb2412e7a0c..3cdf95b1dc9 100644 --- a/kernel/power/main.c +++ b/kernel/power/main.c @@ -20,6 +20,7 @@ #include #include #include +#include #include "power.h" @@ -230,9 +231,14 @@ static int enter_state(suspend_state_t state) if (!valid_state(state)) return -ENODEV; + if (!mutex_trylock(&pm_mutex)) return -EBUSY; + printk("Syncing filesystems ... "); + sys_sync(); + printk("done.\n"); + pr_debug("PM: Preparing system for %s sleep\n", pm_states[state]); if ((error = suspend_prepare())) goto Unlock; diff --git a/kernel/power/process.c b/kernel/power/process.c index 3434940a3df..dba2f3acb4f 100644 --- a/kernel/power/process.c +++ b/kernel/power/process.c @@ -191,7 +191,6 @@ int freeze_processes(void) if (error) return error; - sys_sync(); error = try_to_freeze_tasks(FREEZER_KERNEL_THREADS); if (error) return error; diff --git a/kernel/power/user.c b/kernel/power/user.c index bd0723a7df3..5bd321bcbb7 100644 --- a/kernel/power/user.c +++ b/kernel/power/user.c @@ -153,6 +153,10 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp, mutex_lock(&pm_mutex); error = pm_notifier_call_chain(PM_HIBERNATION_PREPARE); if (!error) { + printk("Syncing filesystems ... "); + sys_sync(); + printk("done.\n"); + error = freeze_processes(); if (error) thaw_processes(); -- 2.20.1