[PATCH 02/15] mm: page_alloc: update migrate type of pages on pcp when isolating

Marek Szyprowski
2012-01-26T09:01:04Z

From: Michal Nazarewicz <mina86@mina86.com>

This commit changes set_migratetype_isolate() so that it updates
migrate type of pages on pcp list which is saved in their
page_private.

Signed-off-by: Michal Nazarewicz <mina86@mina86.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
---
include/linux/page-isolation.h | 6 ++++++
mm/page_alloc.c | 1 +
mm/page_isolation.c | 24 ++++++++++++++++++++++++
3 files changed, 31 insertions(+), 0 deletions(-)

diff --git a/include/linux/page-isolation.h b/include/linux/page-isolation.h
index 051c1b1..8c02c2b 100644
--- a/include/linux/page-isolation.h
+++ b/include/linux/page-isolation.h
@@ -27,6 +27,12 @@ extern int
test_pages_isolated(unsigned long start_pfn, unsigned long end_pfn);

/*
+ * Check all pages in pageblock, find the ones on pcp list, and set
+ * their page_private to MIGRATE_ISOLATE.
+ */
+extern void update_pcp_isolate_block(unsigned long pfn);
+
+/*
* Internal funcs.Changes pageblock's migrate type.
* Please use make_pagetype_isolated()/make_pagetype_movable().
*/
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index e1c5656..70709e7 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -5465,6 +5465,7 @@ out:
if (!ret) {
set_pageblock_migratetype(page, MIGRATE_ISOLATE);
move_freepages_block(zone, page, MIGRATE_ISOLATE);
+ update_pcp_isolate_block(pfn);
}

spin_unlock_irqrestore(&zone->lock, flags);
diff --git a/mm/page_isolation.c b/mm/page_isolation.c
index 4ae42bb..9ea2f6e 100644
--- a/mm/page_isolation.c
+++ b/mm/page_isolation.c
@@ -139,3 +139,27 @@ int test_pages_isolated(unsigned long start_pfn, unsigned long end_pfn)
spin_unlock_irqrestore(&zone->lock, flags);
return ret ? 0 : -EBUSY;
}
+
+/* must hold zone->lock */
+void update_pcp_isolate_block(unsigned long pfn)
+{
+ unsigned long end_pfn = pfn + pageblock_nr_pages;
+ struct page *page;
+
+ while (pfn < end_pfn) {
+ if (!pfn_valid_within(pfn)) {
+ ++pfn;
+ continue;
+ }
+
+ page = pfn_to_page(pfn);
+ if (PageBuddy(page)) {
+ pfn += 1 << page_order(page);
+ } else if (page_count(page) == 0) {
+ set_page_private(page, MIGRATE_ISOLATE);
+ ++pfn;
+ } else {
+ ++pfn;
+ }
+ }
+}
--
1.7.1.569.g6f426