+ mm-page_owner-fetch-backtrace-only-for-tracked-pages.patch added to -mm tree

+ mm-page_owner-fetch-backtrace-only-for-tracked-pages.patch added to -mm tree

[akpm]

The patch titled
     Subject: mm: page_owner: fetch backtrace only for tracked pages
has been added to the -mm tree.  Its filename is
     mm-page_owner-fetch-backtrace-only-for-tracked-pages.patch

This patch should soon appear at
    https://ozlabs.org/~akpm/mmots/broken-out/mm-page_owner-fetch-backtrace-only-for-tracked-pages.patch
and later at
    https://ozlabs.org/~akpm/mmotm/broken-out/mm-page_owner-fetch-backtrace-only-for-tracked-pages.patch

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------------------------------------------------------
From: Sergei Trofimovich <slyfox@gentoo.org>
Subject: mm: page_owner: fetch backtrace only for tracked pages

Very minor optimization.

Link: https://lkml.kernel.org/r/20210401212445.3534721-1-slyfox@gentoo.org
Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/page_owner.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

--- a/mm/page_owner.c~mm-page_owner-fetch-backtrace-only-for-tracked-pages
+++ a/mm/page_owner.c
@@ -147,15 +147,15 @@ void __reset_page_owner(struct page *pag
 {
 	int i;
 	struct page_ext *page_ext;
-	depot_stack_handle_t handle = 0;
+	depot_stack_handle_t handle;
 	struct page_owner *page_owner;
 	u64 free_ts_nsec = local_clock();
 
-	handle = save_stack(GFP_NOWAIT | __GFP_NOWARN);
-
 	page_ext = lookup_page_ext(page);
 	if (unlikely(!page_ext))
 		return;
+
+	handle = save_stack(GFP_NOWAIT | __GFP_NOWARN);
 	for (i = 0; i < (1 << order); i++) {
 		__clear_bit(PAGE_EXT_OWNER_ALLOCATED, &page_ext->flags);
 		page_owner = get_page_owner(page_ext);
_

Patches currently in -mm which might be from slyfox@gentoo.org are

ia64-fix-user_stack_pointer-for-ptrace.patch
ia64-drop-unused-ia64_fw_emu-ifdef.patch
ia64-simplify-code-flow-around-swiotlb-init.patch
ia64-fix-efi_debug-build.patch
ia64-mca-always-make-ia64_mca_debug-an-expression.patch
mm-page_owner-fetch-backtrace-only-for-tracked-pages.patch
mm-page_alloc-ignore-init_on_free=1-for-debug_pagealloc=1.patch