mm: avoid uninitialized variable in tracepoint

A newly added tracepoint in the hugepage code uses a variable in the
error handling that is not initialized at that point:

include/trace/events/huge_memory.h:81:230: error: 'isolated' may be used uninitialized in this function [-Werror=maybe-uninitialized]

The result is relatively harmless, as the trace data will in rare
cases contain incorrect data.

This works around the problem by adding an explicit initialization.

Signed-off-by: Arnd Bergmann <[email protected]>
Fixes: 7d2eba0557 ("mm: add tracepoint for scanning pages")
Reviewed-by: Ebru Akagunduz <[email protected]>
Acked-by: David Rientjes <[email protected]>
Cc: Kirill A. Shutemov <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
This commit is contained in:
Arnd Bergmann 2016-01-18 21:50:26 +01:00 • committed by Linus Torvalds
commit 629d9d1caf

View file

@ -2320,7 +2320,7 @@ static void collapse_huge_page(struct mm_struct *mm,
pgtable_t pgtable;
struct page *new_page;
spinlock_t *pmd_ptl, *pte_ptl;
int isolated, result = 0;
int isolated = 0, result = 0;
unsigned long hstart, hend;
struct mem_cgroup *memcg;
unsigned long mmun_start; /* For mmu_notifiers */