[PATCH] proc: Avoid unused variable warning in pagemap_pmd_range()

From: Nathan Chancellor
Date: Mon Feb 07 2022 - 12:22:57 EST


When building with CONFIG_TRANSPARENT_HUGEPAGE=n, there is a warning
about migration being unused:

fs/proc/task_mmu.c:1444:7: warning: unused variable 'migration' [-Wunused-variable]
bool migration = false;
^
1 warning generated.

Move the ifdef preprocessor directive up to include migration so it is
only included in the file when it is used.

Signed-off-by: Nathan Chancellor <nathan@xxxxxxxxxx>
---

This is a fix for fs-proc-task_mmuc-dont-read-mapcount-for-migration-entry-v4.patch.

fs/proc/task_mmu.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index bc2f46033231..6e97ed775074 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -1441,9 +1441,9 @@ static int pagemap_pmd_range(pmd_t *pmdp, unsigned long addr, unsigned long end,
spinlock_t *ptl;
pte_t *pte, *orig_pte;
int err = 0;
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
bool migration = false;

-#ifdef CONFIG_TRANSPARENT_HUGEPAGE
ptl = pmd_trans_huge_lock(pmdp, vma);
if (ptl) {
u64 flags = 0, frame = 0;

base-commit: b3c0a155ef77550d48f6eb7c6fdd6075764a5622
--
2.35.1