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>

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index b62ea569aa43b8544c3d485fb5a7f3e03ef65af6..78689cba178f00377c4beec29ceeeddcdd13e0b2 100644 (file)
--- 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);
 }
 
 /*