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.
Signed-off-by: Imran Khan <[email protected]>
Suggested-by: Vlastimil Babka <[email protected]>
---
include/linux/stackdepot.h | 2 ++
lib/stackdepot.c | 17 +++++++++++++++++
mm/kasan/report.c | 15 +++------------
mm/page_owner.c | 13 ++++---------
4 files changed, 26 insertions(+), 21 deletions(-)
diff --git a/include/linux/stackdepot.h b/include/linux/stackdepot.h
index 6bb4bc1a5f54..d77a30543dd4 100644
--- a/include/linux/stackdepot.h
+++ b/include/linux/stackdepot.h
@@ -19,6 +19,8 @@ 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);
+
unsigned int filter_irq_stacks(unsigned long *entries, unsigned int nr_entries);
#ifdef CONFIG_STACKDEPOT
diff --git a/lib/stackdepot.c b/lib/stackdepot.c
index 67439c082490..873aeb152f52 100644
--- a/lib/stackdepot.c
+++ b/lib/stackdepot.c
@@ -214,6 +214,23 @@ static inline struct stack_record *find_stack(struct stack_record *bucket,
return NULL;
}
+/**
+ * stack_depot_print - print stack entries from a depot
+ *
+ * @handle: 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);
+ 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 884a950c7026..3239fd8f8747 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 d24ed221357c..7918770c2b2b 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)
--
2.30.2
On 9/2/21 02:01, Imran Khan wrote:
> 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.
>
> Signed-off-by: Imran Khan <[email protected]>
> Suggested-by: Vlastimil Babka <[email protected]>
Acked-by: Vlastimil Babka <[email protected]>
On Thu, Sep 2, 2021 at 9:55 AM Vlastimil Babka <[email protected]> wrote:
>
> On 9/2/21 02:01, Imran Khan wrote:
> > 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.
> >
> > Signed-off-by: Imran Khan <[email protected]>
> > Suggested-by: Vlastimil Babka <[email protected]>
>
> Acked-by: Vlastimil Babka <[email protected]>
Reviewed-by: Alexander Potapenko <[email protected]>
--
Alexander Potapenko
Software Engineer
Google Germany GmbH
Erika-Mann-Straße, 33
80636 München
Geschäftsführer: Paul Manicle, Halimah DeLaine Prado
Registergericht und -nummer: Hamburg, HRB 86891
Sitz der Gesellschaft: Hamburg
On 9/2/21 02:01, Imran Khan wrote:
> 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.
>
> Signed-off-by: Imran Khan <[email protected]>
> Suggested-by: Vlastimil Babka <[email protected]>
> ---
> include/linux/stackdepot.h | 2 ++
> lib/stackdepot.c | 17 +++++++++++++++++
> mm/kasan/report.c | 15 +++------------
> mm/page_owner.c | 13 ++++---------
> 4 files changed, 26 insertions(+), 21 deletions(-)
>
> diff --git a/include/linux/stackdepot.h b/include/linux/stackdepot.h
> index 6bb4bc1a5f54..d77a30543dd4 100644
> --- a/include/linux/stackdepot.h
> +++ b/include/linux/stackdepot.h
> @@ -19,6 +19,8 @@ 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);
> +
> unsigned int filter_irq_stacks(unsigned long *entries, unsigned int nr_entries);
>
> #ifdef CONFIG_STACKDEPOT
> diff --git a/lib/stackdepot.c b/lib/stackdepot.c
> index 67439c082490..873aeb152f52 100644
> --- a/lib/stackdepot.c
> +++ b/lib/stackdepot.c
> @@ -214,6 +214,23 @@ static inline struct stack_record *find_stack(struct stack_record *bucket,
> return NULL;
> }
>
> +/**
> + * stack_depot_print - print stack entries from a depot
> + *
> + * @handle: 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);
Maybe this should also skip stack_trace_print when nr_entries is 0, to avoid
the warning. While the callers added by this patch check handle != 0, future
ones might not.
On 14/9/21 7:01 pm, Vlastimil Babka wrote:
> On 9/2/21 02:01, Imran Khan wrote:
>> 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.
>>
[...]
>>
>> +/**
>> + * stack_depot_print - print stack entries from a depot
>> + *
>> + * @handle: 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);
>
> Maybe this should also skip stack_trace_print when nr_entries is 0, to avoid
> the warning. While the callers added by this patch check handle != 0, future
> ones might not.
>
Agree. I have incorporated this suggestion in latest version [1]
[1]
https://lore.kernel.org/lkml/[email protected]/
Thanks
-- Imran