Re: [aa:autonuma27 52/56] mm/mempolicy.c:1183:4: error: implicit declaration of function 'trace_numa

[Andrew Jones <drjones@redhat.com>]

On Fri, Oct 05, 2012 at 09:20:03AM +0800, Fengguang Wu wrote:
> Hi Andrew,
> 
> FYI, kernel build failed on
> 
> tree:   git://git.kernel.org/pub/scm/linux/kernel/git/andrea/aa.git autonuma27
> head:   f3c62c0eadc7fe51f755543fe0b0830b937f8406
> commit: 318fc9096f65d1187e19cba0881e2b796380fec7 [52/56] autonuma: trace: numa: add numa_migratepages trace events
> config: ia64-allnoconfig
> 
> All error/warnings:
> 
> mm/mempolicy.c: In function 'do_mbind':
> mm/mempolicy.c:1183:4: error: implicit declaration of function 'trace_numa_migratepages_nodemask_begin' [-Werror=implicit-function-declaration]
> mm/mempolicy.c:1190:4: error: implicit declaration of function 'trace_numa_migratepages_nodemask_end' [-Werror=implicit-function-declaration]
> cc1: some warnings being treated as errors

Thanks for the bug report. With your allnoconfig test build I
see that I didn't pay enough attention to the scope of
CONFIG_MIGRATION, and that do_mbind is outside it. I guess
do_mbind prefers to fail more elaborately when there isn't
migration support than do_migrate_pages does. Rather than just
returning ENOSYS it actually attempts to migrate pages with
a NULL returning get_new_page function, which eventually
forces do_mbind to return ENOMEM.

I'll send Andrea a fix for his tree.

Drew

> 
> vim +1183 mm/mempolicy.c
> 
> 6ce3c4c0 (Christoph Lameter 2006-01-08  1177) 	if (!IS_ERR(vma)) {
> 6ce3c4c0 (Christoph Lameter 2006-01-08  1178) 		int nr_failed = 0;
> 6ce3c4c0 (Christoph Lameter 2006-01-08  1179) 
> 9d8cebd4 (KOSAKI Motohiro   2010-03-05  1180) 		err = mbind_range(mm, start, end, new);
> 7e2ab150 (Christoph Lameter 2006-02-01  1181) 
> cf608ac1 (Minchan Kim       2010-10-26  1182) 		if (!list_empty(&pagelist)) {
> 318fc909 (Andrew Jones      2012-10-02 @1183) 			trace_numa_migratepages_nodemask_begin(mm, &pagelist,
> 318fc909 (Andrew Jones      2012-10-02  1184) 							       NULL, nmask);
> 95a402c3 (Christoph Lameter 2006-06-23  1185) 			nr_failed = migrate_pages(&pagelist, new_vma_page,
> 7f0f2496 (Mel Gorman        2011-01-13  1186) 						(unsigned long)vma,
> 
> ---
> 0-DAY kernel build testing backend         Open Source Technology Center
> Fengguang Wu, Yuanhan Liu                              Intel Corporation