On Fri, Jan 13, 2012 at 09:04:31PM +0100, Michal Nazarewicz wrote:

quoted

On Thu, Dec 29, 2011 at 01:39:05PM +0100, Marek Szyprowski wrote:

quoted

From: Michal Nazarewicz <redacted>
+	/* Make sure all pages are isolated. */
+	if (!ret) {
+		lru_add_drain_all();
+		drain_all_pages();
+		if (WARN_ON(test_pages_isolated(start, end)))
+			ret = -EBUSY;
+	}

On Tue, 10 Jan 2012 15:16:13 +0100, Mel Gorman [off-list ref] wrote:

quoted

Another global IPI seems overkill. Drain pages only from the local CPU
(drain_pages(get_cpu()); put_cpu()) and test if the pages are isolated.

Is get_cpu() + put_cpu() required? Won't drain_local_pages() work?

drain_local_pages() calls smp_processor_id() without preemption
disabled. 

-- 
Mel Gorman
SUSE Labs