mm: use early_pfn_to_nid in page_ext_init

page_ext_init() checks suitable pages with pfn_to_nid(), but
pfn_to_nid() depends on memmap which will not be setup fully until
page_alloc_init_late() is done.  Use early_pfn_to_nid() instead of
pfn_to_nid() so that page extension could be still used early even
though CONFIG_ DEFERRED_STRUCT_PAGE_INIT is enabled and catch early page
allocation call sites.

Suggested by Joonsoo Kim [1], this fix basically undoes the change
introduced by commit b8f1a75d61 ("mm: call page_ext_init() after all
struct pages are initialized") and fixes the same problem with a better
approach.

[1] http://lkml.kernel.org/r/CAAmzW4OUmyPwQjvd7QUfc6W1Aic__TyAuH80MLRZNMxKy0-wPQ@mail.gmail.com

Link: http://lkml.kernel.org/r/1464198689-23458-1-git-send-email-yang.shi@linaro.org
Signed-off-by: Yang Shi <yang.shi@linaro.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Yang Shi 2016-05-27 14:27:30 -07:00 committed by Linus Torvalds
parent f871f19135
commit fe53ca5427
2 changed files with 4 additions and 3 deletions

View file

@ -607,6 +607,7 @@ asmlinkage __visible void __init start_kernel(void)
initrd_start = 0;
}
#endif
page_ext_init();
debug_objects_mem_init();
kmemleak_init();
setup_per_cpu_pageset();
@ -1003,8 +1004,6 @@ static noinline void __init kernel_init_freeable(void)
sched_init_smp();
page_alloc_init_late();
/* Initialize page ext after all struct pages are initializaed */
page_ext_init();
do_basic_setup();

View file

@ -390,8 +390,10 @@ void __init page_ext_init(void)
* We know some arch can have a nodes layout such as
* -------------pfn-------------->
* N0 | N1 | N2 | N0 | N1 | N2|....
*
* Take into account DEFERRED_STRUCT_PAGE_INIT.
*/
if (pfn_to_nid(pfn) != nid)
if (early_pfn_to_nid(pfn) != nid)
continue;
if (init_section_page_ext(pfn, nid))
goto oom;