mm: per-thread vma caching

[linux-2.6-block.git] / include / linux / sched.h

diff --git a/include/linux/sched.h b/include/linux/sched.h
index 7cb07fd266808835ca8d4309891f19567cbe7503..642477dd814acf6640ab8631bc56ab38808a7f36 100644 (file)
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -132,6 +132,10 @@ struct perf_event_context;
 struct blk_plug;
 struct filename;
 
+#define VMACACHE_BITS 2
+#define VMACACHE_SIZE (1U << VMACACHE_BITS)
+#define VMACACHE_MASK (VMACACHE_SIZE - 1)
+
 /*
  * List of flags we want to share for kernel threads,
  * if only because they are not used by them anyway.
@@ -1235,6 +1239,9 @@ struct task_struct {
 #ifdef CONFIG_COMPAT_BRK
        unsigned brk_randomized:1;
 #endif
+       /* per-thread vma caching */
+       u32 vmacache_seqnum;
+       struct vm_area_struct *vmacache[VMACACHE_SIZE];
 #if defined(SPLIT_RSS_COUNTING)
        struct task_rss_stat    rss_stat;
 #endif