[PATCH] balance_dirty_pages_ratelimited: take nr_pages arg
Modify balance_dirty_pages_ratelimited() so that it can take a
number-of-pages-which-I-just-dirtied argument. For msync().
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index c1052ee..c67ddc4 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -256,8 +256,9 @@
}
/**
- * balance_dirty_pages_ratelimited - balance dirty memory state
+ * balance_dirty_pages_ratelimited_nr - balance dirty memory state
* @mapping: address_space which was dirtied
+ * @nr_pages: number of pages which the caller has just dirtied
*
* Processes which are dirtying memory should call in here once for each page
* which was newly dirtied. The function will periodically check the system's
@@ -268,10 +269,12 @@
* limit we decrease the ratelimiting by a lot, to prevent individual processes
* from overshooting the limit by (ratelimit_pages) each.
*/
-void balance_dirty_pages_ratelimited(struct address_space *mapping)
+void balance_dirty_pages_ratelimited_nr(struct address_space *mapping,
+ unsigned long nr_pages_dirtied)
{
- static DEFINE_PER_CPU(int, ratelimits) = 0;
- long ratelimit;
+ static DEFINE_PER_CPU(unsigned long, ratelimits) = 0;
+ unsigned long ratelimit;
+ unsigned long *p;
ratelimit = ratelimit_pages;
if (dirty_exceeded)
@@ -281,15 +284,18 @@
* Check the rate limiting. Also, we do not want to throttle real-time
* tasks in balance_dirty_pages(). Period.
*/
- if (get_cpu_var(ratelimits)++ >= ratelimit) {
- __get_cpu_var(ratelimits) = 0;
- put_cpu_var(ratelimits);
+ preempt_disable();
+ p = &__get_cpu_var(ratelimits);
+ *p += nr_pages_dirtied;
+ if (unlikely(*p >= ratelimit)) {
+ *p = 0;
+ preempt_enable();
balance_dirty_pages(mapping);
return;
}
- put_cpu_var(ratelimits);
+ preempt_enable();
}
-EXPORT_SYMBOL(balance_dirty_pages_ratelimited);
+EXPORT_SYMBOL(balance_dirty_pages_ratelimited_nr);
void throttle_vm_writeout(void)
{