Merge branch 'akpm' (patches from Andrew)

Merge third patch-bomb from Andrew Morton:

 - more ocfs2 changes

 - a few hotfixes

 - Andy's compat cleanups

 - misc fixes to fatfs, ptrace, coredump, cpumask, creds, eventfd,
   panic, ipmi, kgdb, profile, kfifo, ubsan, etc.

 - many rapidio updates: fixes, new drivers.

 - kcov: kernel code coverage feature.  Like gcov, but not
   "prohibitively expensive".

 - extable code consolidation for various archs

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (81 commits)
  ia64/extable: use generic search and sort routines
  x86/extable: use generic search and sort routines
  s390/extable: use generic search and sort routines
  alpha/extable: use generic search and sort routines
  kernel/...: convert pr_warning to pr_warn
  drivers: dma-coherent: use memset_io for DMA_MEMORY_IO mappings
  drivers: dma-coherent: use MEMREMAP_WC for DMA_MEMORY_MAP
  memremap: add MEMREMAP_WC flag
  memremap: don't modify flags
  kernel/signal.c: add compile-time check for __ARCH_SI_PREAMBLE_SIZE
  mm/mprotect.c: don't imply PROT_EXEC on non-exec fs
  ipc/sem: make semctl setting sempid consistent
  ubsan: fix tree-wide -Wmaybe-uninitialized false positives
  kfifo: fix sparse complaints
  scripts/gdb: account for changes in module data structure
  scripts/gdb: add cmdline reader command
  scripts/gdb: add version command
  kernel: add kcov code coverage
  profile: hide unused functions when !CONFIG_PROC_FS
  hpwdt: use nmi_panic() when kernel panics in NMI handler
  ...

1 files changed, 13 insertions, 8 deletions

diff --git a/kernel/hung_task.c b/kernel/hung_task.c
index e0f90c2b57aa..d234022805dc 100644
--- a/kernel/hung_task.c
+++ b/kernel/hung_task.c
@@ -185,10 +185,12 @@ static void check_hung_uninterruptible_tasks(unsigned long timeout)
 	rcu_read_unlock();
 }
 
-static unsigned long timeout_jiffies(unsigned long timeout)
+static long hung_timeout_jiffies(unsigned long last_checked,
+				 unsigned long timeout)
 {
 	/* timeout of 0 will disable the watchdog */
-	return timeout ? timeout * HZ : MAX_SCHEDULE_TIMEOUT;
+	return timeout ? last_checked - jiffies + timeout * HZ :
+		MAX_SCHEDULE_TIMEOUT;
 }
 
 /*
@@ -224,18 +226,21 @@ EXPORT_SYMBOL_GPL(reset_hung_task_detector);
  */
 static int watchdog(void *dummy)
 {
+	unsigned long hung_last_checked = jiffies;
+
 	set_user_nice(current, 0);
 
 	for ( ; ; ) {
 		unsigned long timeout = sysctl_hung_task_timeout_secs;
+		long t = hung_timeout_jiffies(hung_last_checked, timeout);
 
-		while (schedule_timeout_interruptible(timeout_jiffies(timeout)))
-			timeout = sysctl_hung_task_timeout_secs;
-
-		if (atomic_xchg(&reset_hung_task, 0))
+		if (t <= 0) {
+			if (!atomic_xchg(&reset_hung_task, 0))
+				check_hung_uninterruptible_tasks(timeout);
+			hung_last_checked = jiffies;
 			continue;
-
-		check_hung_uninterruptible_tasks(timeout);
+		}
+		schedule_timeout_interruptible(t);
 	}
 
 	return 0;