mm: vmalloc use mutex for purge

The vmalloc purge lock can be a mutex so we can sleep while a purge is
going on (purge involves a global kernel TLB invalidate, so it can take
quite a while).

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 5 insertions, 4 deletions

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index b62ea569aa43..78689cba178f 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -14,6 +14,7 @@
 #include <linux/highmem.h>
 #include <linux/slab.h>
 #include <linux/spinlock.h>
+#include <linux/mutex.h>
 #include <linux/interrupt.h>
 #include <linux/proc_fs.h>
 #include <linux/seq_file.h>
@@ -473,7 +474,7 @@ static atomic_t vmap_lazy_nr = ATOMIC_INIT(0);
 static void __purge_vmap_area_lazy(unsigned long *start, unsigned long *end,
                                         int sync, int force_flush)
 {
-        static DEFINE_SPINLOCK(purge_lock);
+        static DEFINE_MUTEX(purge_lock);
         LIST_HEAD(valist);
         struct vmap_area *va;
         int nr = 0;
@@ -484,10 +485,10 @@ static void __purge_vmap_area_lazy(unsigned long *start, unsigned long *end,
          * the case that isn't actually used at the moment anyway.
          */
         if (!sync && !force_flush) {
-                if (!spin_trylock(&purge_lock))
+                if (!mutex_trylock(&purge_lock))
                         return;
         } else
-                spin_lock(&purge_lock);
+                mutex_lock(&purge_lock);
 
         rcu_read_lock();
         list_for_each_entry_rcu(va, &vmap_area_list, list) {
@@ -519,7 +520,7 @@ static void __purge_vmap_area_lazy(unsigned long *start, unsigned long *end,
                         __free_vmap_area(va);
                 spin_unlock(&vmap_area_lock);
         }
-        spin_unlock(&purge_lock);
+        mutex_unlock(&purge_lock);
 }
 
 /*