mm/vmalloc: keep a separate lazy-free list
When mixing lots of vmallocs and set_memory_*() (which calls
vm_unmap_aliases()) I encountered situations where the performance
degraded severely due to the walking of the entire vmap_area list each
invocation.
One simple improvement is to add the lazily freed vmap_area to a
separate lockless free list, such that we then avoid having to walk the
full list on each purge.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Roman Pen <r.peniaev@gmail.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Roman Pen <r.peniaev@gmail.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h
index d1f1d33..957adb7 100644
--- a/include/linux/vmalloc.h
+++ b/include/linux/vmalloc.h
@@ -4,6 +4,7 @@
#include <linux/spinlock.h>
#include <linux/init.h>
#include <linux/list.h>
+#include <linux/llist.h>
#include <asm/page.h> /* pgprot_t */
#include <linux/rbtree.h>
@@ -44,7 +45,7 @@
unsigned long flags;
struct rb_node rb_node; /* address sorted rbtree */
struct list_head list; /* address sorted list */
- struct list_head purge_list; /* "lazy purge" list */
+ struct llist_node purge_list; /* "lazy purge" list */
struct vm_struct *vm;
struct rcu_head rcu_head;
};