From 505be48165fa2f2cb795659b4fc61f35563d105e Mon Sep 17 00:00:00 2001
From: Imran Khan <imran.f.khan@oracle.com>
Date: Mon, 8 Nov 2021 18:33:12 -0800
Subject: [PATCH] lib, stackdepot: add helper to print stack entries
To print a stack entries, users of stackdepot, first use stack_depot_fetch
to get a list of stack entries and then use stack_trace_print to print
this list. Provide a helper in stackdepot to print stack entries based on
stackdepot handle. Also change above mentioned users to use this helper.
Link: https://lkml.kernel.org/r/20210915014806.3206938-3-imran.f.khan@oracle.com
Signed-off-by: Imran Khan <imran.f.khan@oracle.com>
Suggested-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: David Airlie <airlied@linux.ie>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
include/linux/stackdepot.h | 2 ++
lib/stackdepot.c | 18 ++++++++++++++++++
mm/kasan/report.c | 15 +++------------
mm/page_owner.c | 13 ++++---------
4 files changed, 27 insertions(+), 21 deletions(-)
diff --git a/include/linux/stackdepot.h b/include/linux/stackdepot.h
index d29860966bc91..8ab37500fcba8 100644
--- a/include/linux/stackdepot.h
+++ b/include/linux/stackdepot.h
@@ -25,6 +25,8 @@ depot_stack_handle_t stack_depot_save(unsigned long *entries,
unsigned int stack_depot_fetch(depot_stack_handle_t handle,
unsigned long **entries);
+void stack_depot_print(depot_stack_handle_t stack);
+
#ifdef CONFIG_STACKDEPOT
int stack_depot_init(void);
#else
diff --git a/lib/stackdepot.c b/lib/stackdepot.c
index f034f095c627e..4e1f2982d0fa7 100644
--- a/lib/stackdepot.c
+++ b/lib/stackdepot.c
@@ -213,6 +213,24 @@ static inline struct stack_record *find_stack(struct stack_record *bucket,
return NULL;
}
+/**
+ * stack_depot_print - print stack entries from a depot
+ *
+ * @stack: Stack depot handle which was returned from
+ * stack_depot_save().
+ *
+ */
+void stack_depot_print(depot_stack_handle_t stack)
+{
+ unsigned long *entries;
+ unsigned int nr_entries;
+
+ nr_entries = stack_depot_fetch(stack, &entries);
+ if (nr_entries > 0)
+ stack_trace_print(entries, nr_entries, 0);
+}
+EXPORT_SYMBOL_GPL(stack_depot_print);
+
/**
* stack_depot_fetch - Fetch stack entries from a depot
*
diff --git a/mm/kasan/report.c b/mm/kasan/report.c
index 884a950c70265..3239fd8f87475 100644
--- a/mm/kasan/report.c
+++ b/mm/kasan/report.c
@@ -132,20 +132,11 @@ static void end_report(unsigned long *flags, unsigned long addr)
kasan_enable_current();
}
-static void print_stack(depot_stack_handle_t stack)
-{
- unsigned long *entries;
- unsigned int nr_entries;
-
- nr_entries = stack_depot_fetch(stack, &entries);
- stack_trace_print(entries, nr_entries, 0);
-}
-
static void print_track(struct kasan_track *track, const char *prefix)
{
pr_err("%s by task %u:\n", prefix, track->pid);
if (track->stack) {
- print_stack(track->stack);
+ stack_depot_print(track->stack);
} else {
pr_err("(stack is not available)\n");
}
@@ -214,12 +205,12 @@ static void describe_object_stacks(struct kmem_cache *cache, void *object,
return;
if (alloc_meta->aux_stack[0]) {
pr_err("Last potentially related work creation:\n");
- print_stack(alloc_meta->aux_stack[0]);
+ stack_depot_print(alloc_meta->aux_stack[0]);
pr_err("\n");
}
if (alloc_meta->aux_stack[1]) {
pr_err("Second to last potentially related work creation:\n");
- print_stack(alloc_meta->aux_stack[1]);
+ stack_depot_print(alloc_meta->aux_stack[1]);
pr_err("\n");
}
#endif
diff --git a/mm/page_owner.c b/mm/page_owner.c
index 62402d22539b8..eff29be1218bc 100644
--- a/mm/page_owner.c
+++ b/mm/page_owner.c
@@ -394,8 +394,6 @@ void __dump_page_owner(const struct page *page)
struct page_ext *page_ext = lookup_page_ext(page);
struct page_owner *page_owner;
depot_stack_handle_t handle;
- unsigned long *entries;
- unsigned int nr_entries;
gfp_t gfp_mask;
int mt;
@@ -423,20 +421,17 @@ void __dump_page_owner(const struct page *page)
page_owner->pid, page_owner->ts_nsec, page_owner->free_ts_nsec);
handle = READ_ONCE(page_owner->handle);
- if (!handle) {
+ if (!handle)
pr_alert("page_owner allocation stack trace missing\n");
- } else {
- nr_entries = stack_depot_fetch(handle, &entries);
- stack_trace_print(entries, nr_entries, 0);
- }
+ else
+ stack_depot_print(handle);
handle = READ_ONCE(page_owner->free_handle);
if (!handle) {
pr_alert("page_owner free stack trace missing\n");
} else {
- nr_entries = stack_depot_fetch(handle, &entries);
pr_alert("page last free stack trace:\n");
- stack_trace_print(entries, nr_entries, 0);
+ stack_depot_print(handle);
}
if (page_owner->last_migrate_reason != -1)
--
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