This change is in response to discussion at [1].
The patch has been created on top of my earlier changes [2] and [3].
If needed I can resend all of these patches together, though my
earlier patches have been Acked.
[1] https://lore.kernel.org/lkml/[email protected]/
[2] https://lore.kernel.org/lkml/[email protected]/
[3] https://lore.kernel.org/lkml/[email protected]/
Imran Khan (1):
lib, stackdepot: Add helper to print stack entries into buffer.
drivers/gpu/drm/drm_dp_mst_topology.c | 5 +----
drivers/gpu/drm/drm_mm.c | 5 +----
drivers/gpu/drm/i915/i915_vma.c | 5 +----
drivers/gpu/drm/i915/intel_runtime_pm.c | 20 +++++---------------
include/linux/stackdepot.h | 3 +++
lib/stackdepot.c | 23 +++++++++++++++++++++++
mm/page_owner.c | 5 +----
7 files changed, 35 insertions(+), 31 deletions(-)
--
2.30.2
To print stack entries into a buffer, users of stackdepot,
first get a list of stack entries using stack_depot_fetch
and then print this list into a buffer using stack_trace_snprint.
Provide a helper in stackdepot for this purpose.
Also change above mentioned users to use this helper.
Signed-off-by: Imran Khan <[email protected]>
Suggested-by: Vlastimil Babka <[email protected]>
---
drivers/gpu/drm/drm_dp_mst_topology.c | 5 +----
drivers/gpu/drm/drm_mm.c | 5 +----
drivers/gpu/drm/i915/i915_vma.c | 5 +----
drivers/gpu/drm/i915/intel_runtime_pm.c | 20 +++++---------------
include/linux/stackdepot.h | 3 +++
lib/stackdepot.c | 23 +++++++++++++++++++++++
mm/page_owner.c | 5 +----
7 files changed, 35 insertions(+), 31 deletions(-)
diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
index 86d13d6bc463..2d1adab9e360 100644
--- a/drivers/gpu/drm/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/drm_dp_mst_topology.c
@@ -1668,13 +1668,10 @@ __dump_topology_ref_history(struct drm_dp_mst_topology_ref_history *history,
for (i = 0; i < history->len; i++) {
const struct drm_dp_mst_topology_ref_entry *entry =
&history->entries[i];
- ulong *entries;
- uint nr_entries;
u64 ts_nsec = entry->ts_nsec;
u32 rem_nsec = do_div(ts_nsec, 1000000000);
- nr_entries = stack_depot_fetch(entry->backtrace, &entries);
- stack_trace_snprint(buf, PAGE_SIZE, entries, nr_entries, 4);
+ stack_depot_snprint(entry->backtrace, buf, PAGE_SIZE, 4);
drm_printf(&p, " %d %ss (last at %5llu.%06u):\n%s",
entry->count,
diff --git a/drivers/gpu/drm/drm_mm.c b/drivers/gpu/drm/drm_mm.c
index 93d48a6f04ab..ca04d7f6f7b5 100644
--- a/drivers/gpu/drm/drm_mm.c
+++ b/drivers/gpu/drm/drm_mm.c
@@ -118,8 +118,6 @@ static noinline void save_stack(struct drm_mm_node *node)
static void show_leaks(struct drm_mm *mm)
{
struct drm_mm_node *node;
- unsigned long *entries;
- unsigned int nr_entries;
char *buf;
buf = kmalloc(BUFSZ, GFP_KERNEL);
@@ -133,8 +131,7 @@ static void show_leaks(struct drm_mm *mm)
continue;
}
- nr_entries = stack_depot_fetch(node->stack, &entries);
- stack_trace_snprint(buf, BUFSZ, entries, nr_entries, 0);
+ stack_depot_snprint(node->stack, buf, BUFSZ);
DRM_ERROR("node [%08llx + %08llx]: inserted at\n%s",
node->start, node->size, buf);
}
diff --git a/drivers/gpu/drm/i915/i915_vma.c b/drivers/gpu/drm/i915/i915_vma.c
index 4b7fc4647e46..f2d9ed375109 100644
--- a/drivers/gpu/drm/i915/i915_vma.c
+++ b/drivers/gpu/drm/i915/i915_vma.c
@@ -56,8 +56,6 @@ void i915_vma_free(struct i915_vma *vma)
static void vma_print_allocator(struct i915_vma *vma, const char *reason)
{
- unsigned long *entries;
- unsigned int nr_entries;
char buf[512];
if (!vma->node.stack) {
@@ -66,8 +64,7 @@ static void vma_print_allocator(struct i915_vma *vma, const char *reason)
return;
}
- nr_entries = stack_depot_fetch(vma->node.stack, &entries);
- stack_trace_snprint(buf, sizeof(buf), entries, nr_entries, 0);
+ stack_depot_snprint(vma->node.stack, buf, sizeof(buf), 0);
DRM_DEBUG_DRIVER("vma.node [%08llx + %08llx] %s: inserted at %s\n",
vma->node.start, vma->node.size, reason, buf);
}
diff --git a/drivers/gpu/drm/i915/intel_runtime_pm.c b/drivers/gpu/drm/i915/intel_runtime_pm.c
index eaf7688f517d..cc312f0a05eb 100644
--- a/drivers/gpu/drm/i915/intel_runtime_pm.c
+++ b/drivers/gpu/drm/i915/intel_runtime_pm.c
@@ -65,16 +65,6 @@ static noinline depot_stack_handle_t __save_depot_stack(void)
return stack_depot_save(entries, n, GFP_NOWAIT | __GFP_NOWARN);
}
-static void __print_depot_stack(depot_stack_handle_t stack,
- char *buf, int sz, int indent)
-{
- unsigned long *entries;
- unsigned int nr_entries;
-
- nr_entries = stack_depot_fetch(stack, &entries);
- stack_trace_snprint(buf, sz, entries, nr_entries, indent);
-}
-
static void init_intel_runtime_pm_wakeref(struct intel_runtime_pm *rpm)
{
spin_lock_init(&rpm->debug.lock);
@@ -146,12 +136,12 @@ static void untrack_intel_runtime_pm_wakeref(struct intel_runtime_pm *rpm,
if (!buf)
return;
- __print_depot_stack(stack, buf, PAGE_SIZE, 2);
+ stack_depot_snprint(stack, buf, PAGE_SIZE, 2);
DRM_DEBUG_DRIVER("wakeref %x from\n%s", stack, buf);
stack = READ_ONCE(rpm->debug.last_release);
if (stack) {
- __print_depot_stack(stack, buf, PAGE_SIZE, 2);
+ stack_depot_snprint(stack, buf, PAGE_SIZE, 2);
DRM_DEBUG_DRIVER("wakeref last released at\n%s", buf);
}
@@ -183,12 +173,12 @@ __print_intel_runtime_pm_wakeref(struct drm_printer *p,
return;
if (dbg->last_acquire) {
- __print_depot_stack(dbg->last_acquire, buf, PAGE_SIZE, 2);
+ stack_depot_snprint(dbg->last_acquire, buf, PAGE_SIZE, 2);
drm_printf(p, "Wakeref last acquired:\n%s", buf);
}
if (dbg->last_release) {
- __print_depot_stack(dbg->last_release, buf, PAGE_SIZE, 2);
+ stack_depot_snprint(dbg->last_release, buf, PAGE_SIZE, 2);
drm_printf(p, "Wakeref last released:\n%s", buf);
}
@@ -203,7 +193,7 @@ __print_intel_runtime_pm_wakeref(struct drm_printer *p,
rep = 1;
while (i + 1 < dbg->count && dbg->owners[i + 1] == stack)
rep++, i++;
- __print_depot_stack(stack, buf, PAGE_SIZE, 2);
+ stack_depot_print(stack, buf, PAGE_SIZE, 2);
drm_printf(p, "Wakeref x%lu taken at:\n%s", rep, buf);
}
diff --git a/include/linux/stackdepot.h b/include/linux/stackdepot.h
index d77a30543dd4..88b0b4cc9906 100644
--- a/include/linux/stackdepot.h
+++ b/include/linux/stackdepot.h
@@ -19,6 +19,9 @@ depot_stack_handle_t stack_depot_save(unsigned long *entries,
unsigned int stack_depot_fetch(depot_stack_handle_t handle,
unsigned long **entries);
+int stack_depot_snprint(depot_stack_handle_t handle, char *buf, size_t size,
+ int spaces);
+
void stack_depot_print(depot_stack_handle_t stack);
unsigned int filter_irq_stacks(unsigned long *entries, unsigned int nr_entries);
diff --git a/lib/stackdepot.c b/lib/stackdepot.c
index 873aeb152f52..e1c1d7683f6b 100644
--- a/lib/stackdepot.c
+++ b/lib/stackdepot.c
@@ -214,6 +214,29 @@ static inline struct stack_record *find_stack(struct stack_record *bucket,
return NULL;
}
+/**
+ * stack_depot_snprint - print stack entries from a depot into a buffer
+ *
+ * @handle: Stack depot handle which was returned from
+ * stack_depot_save().
+ * @buf: Pointer to the print buffer
+ *
+ * @size: Size of the print buffer
+ *
+ * @spaces: Number of leading spaces to print
+ *
+ * Return: Number of bytes printed.
+ */
+int stack_depot_snprint(depot_stack_handle_t handle, char *buf, size_t size,
+ int spaces)
+{
+ unsigned long *entries;
+ unsigned int nr_entries;
+
+ nr_entries = stack_depot_fetch(handle, &entries);
+ return stack_trace_snprint(buf, size, entries, nr_entries, 0);
+}
+
/**
* stack_depot_print - print stack entries from a depot
*
diff --git a/mm/page_owner.c b/mm/page_owner.c
index 7918770c2b2b..a83f546c06b5 100644
--- a/mm/page_owner.c
+++ b/mm/page_owner.c
@@ -329,8 +329,6 @@ print_page_owner(char __user *buf, size_t count, unsigned long pfn,
depot_stack_handle_t handle)
{
int ret, pageblock_mt, page_mt;
- unsigned long *entries;
- unsigned int nr_entries;
char *kbuf;
count = min_t(size_t, count, PAGE_SIZE);
@@ -361,8 +359,7 @@ print_page_owner(char __user *buf, size_t count, unsigned long pfn,
if (ret >= count)
goto err;
- nr_entries = stack_depot_fetch(handle, &entries);
- ret += stack_trace_snprint(kbuf + ret, count - ret, entries, nr_entries, 0);
+ ret += stack_depot_snprint(handle, kbuf + ret, count - ret, 0);
if (ret >= count)
goto err;
--
2.30.2
On 9/10/21 16:10, Imran Khan wrote:
> To print stack entries into a buffer, users of stackdepot,
> first get a list of stack entries using stack_depot_fetch
> and then print this list into a buffer using stack_trace_snprint.
> Provide a helper in stackdepot for this purpose.
> 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]>
A comment below:
> --- a/lib/stackdepot.c
> +++ b/lib/stackdepot.c
> @@ -214,6 +214,29 @@ static inline struct stack_record *find_stack(struct stack_record *bucket,
> return NULL;
> }
>
> +/**
> + * stack_depot_snprint - print stack entries from a depot into a buffer
> + *
> + * @handle: Stack depot handle which was returned from
> + * stack_depot_save().
> + * @buf: Pointer to the print buffer
> + *
> + * @size: Size of the print buffer
> + *
> + * @spaces: Number of leading spaces to print
> + *
> + * Return: Number of bytes printed.
> + */
> +int stack_depot_snprint(depot_stack_handle_t handle, char *buf, size_t size,
> + int spaces)
> +{
> + unsigned long *entries;
> + unsigned int nr_entries;
> +
> + nr_entries = stack_depot_fetch(handle, &entries);
> + return stack_trace_snprint(buf, size, entries, nr_entries, 0);
stack_trace_snprint() has a WARN_ON(!entries).
So maybe we should not call it if nr_entries is 0 (because e.g. handle was
0) as the warnings are not useful in that case.
On 13/9/21 6:51 pm, Vlastimil Babka wrote:
> On 9/10/21 16:10, Imran Khan wrote:
>> To print stack entries into a buffer, users of stackdepot,
>> first get a list of stack entries using stack_depot_fetch
>> and then print this list into a buffer using stack_trace_snprint.
>> Provide a helper in stackdepot for this purpose.
>> 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]>
>
>
Thanks for the review.
A comment below:
>
>> --- a/lib/stackdepot.c
>> +++ b/lib/stackdepot.c
>> @@ -214,6 +214,29 @@ static inline struct stack_record *find_stack(struct stack_record *bucket,
>> return NULL;
>> }
[...]
>> + */
>> +int stack_depot_snprint(depot_stack_handle_t handle, char *buf, size_t size,
>> + int spaces)
>> +{
>> + unsigned long *entries;
>> + unsigned int nr_entries;
>> +
>> + nr_entries = stack_depot_fetch(handle, &entries);
>> + return stack_trace_snprint(buf, size, entries, nr_entries, 0);
>
> stack_trace_snprint() has a WARN_ON(!entries).
> So maybe we should not call it if nr_entries is 0 (because e.g. handle was
> 0) as the warnings are not useful in that case.
>
Agree. I have addressed this feedback in v2 of patch.
Thanks
-- Imran
On 9/10/21 16:10, Imran Khan wrote:
> This change is in response to discussion at [1].
> The patch has been created on top of my earlier changes [2] and [3].
> If needed I can resend all of these patches together, though my
> earlier patches have been Acked.
I think you sent those at the beginning of merge window, so it would be best
to gather everything in a self-contained series now and resend. I suggested
another change for one of those anyway.
You can of course resend including the Acks you already got, as you did
already with "[PATCH v2 1/1] lib, stackdepot: Add helper to print stack
entries into buffer."
> [1] https://lore.kernel.org/lkml/[email protected]/
> [2] https://lore.kernel.org/lkml/[email protected]/
> [3] https://lore.kernel.org/lkml/[email protected]/
>
> Imran Khan (1):
> lib, stackdepot: Add helper to print stack entries into buffer.
>
> drivers/gpu/drm/drm_dp_mst_topology.c | 5 +----
> drivers/gpu/drm/drm_mm.c | 5 +----
> drivers/gpu/drm/i915/i915_vma.c | 5 +----
> drivers/gpu/drm/i915/intel_runtime_pm.c | 20 +++++---------------
> include/linux/stackdepot.h | 3 +++
> lib/stackdepot.c | 23 +++++++++++++++++++++++
> mm/page_owner.c | 5 +----
> 7 files changed, 35 insertions(+), 31 deletions(-)
>
Hi Vlastimil,
On 14/9/21 7:03 pm, Vlastimil Babka wrote:
> On 9/10/21 16:10, Imran Khan wrote:
>> This change is in response to discussion at [1].
>> The patch has been created on top of my earlier changes [2] and [3].
>> If needed I can resend all of these patches together, though my
>> earlier patches have been Acked.
>
> I think you sent those at the beginning of merge window, so it would be best
> to gather everything in a self-contained series now and resend. I suggested
> another change for one of those anyway.
>
> You can of course resend including the Acks you already got, as you did
> already with "[PATCH v2 1/1] lib, stackdepot: Add helper to print stack
> entries into buffer."
>
Thanks for clarifying this. I have resend consolidated patch as per your
suggestion. This self-contained change set can be seen at [1].
[1]
https://lore.kernel.org/lkml/[email protected]/
>> [1] https://urldefense.com/v3/__https://lore.kernel.org/lkml/[email protected]/__;!!ACWV5N9M2RV99hQ!aF3HSKJ9eit2OvdDk5j_DTKT8rL2SkG6cYL1lLVvegHz5_YTJhN7dSkHgBKeJjupkw$
>> [2] https://urldefense.com/v3/__https://lore.kernel.org/lkml/[email protected]/__;!!ACWV5N9M2RV99hQ!aF3HSKJ9eit2OvdDk5j_DTKT8rL2SkG6cYL1lLVvegHz5_YTJhN7dSkHgBITooNU1w$
>> [3] https://urldefense.com/v3/__https://lore.kernel.org/lkml/[email protected]/__;!!ACWV5N9M2RV99hQ!aF3HSKJ9eit2OvdDk5j_DTKT8rL2SkG6cYL1lLVvegHz5_YTJhN7dSkHgBJcGhmlHA$
>>
>> Imran Khan (1):
>> lib, stackdepot: Add helper to print stack entries into buffer.
>>
>> drivers/gpu/drm/drm_dp_mst_topology.c | 5 +----
>> drivers/gpu/drm/drm_mm.c | 5 +----
>> drivers/gpu/drm/i915/i915_vma.c | 5 +----
>> drivers/gpu/drm/i915/intel_runtime_pm.c | 20 +++++---------------
>> include/linux/stackdepot.h | 3 +++
>> lib/stackdepot.c | 23 +++++++++++++++++++++++
>> mm/page_owner.c | 5 +----
>> 7 files changed, 35 insertions(+), 31 deletions(-)
>>
>
On Sat, 11 Sep 2021, Imran Khan <[email protected]> wrote:
> To print stack entries into a buffer, users of stackdepot,
> first get a list of stack entries using stack_depot_fetch
> and then print this list into a buffer using stack_trace_snprint.
> Provide a helper in stackdepot for this purpose.
> Also change above mentioned users to use this helper.
>
> Signed-off-by: Imran Khan <[email protected]>
> Suggested-by: Vlastimil Babka <[email protected]>
> ---
> drivers/gpu/drm/drm_dp_mst_topology.c | 5 +----
> drivers/gpu/drm/drm_mm.c | 5 +----
> drivers/gpu/drm/i915/i915_vma.c | 5 +----
> drivers/gpu/drm/i915/intel_runtime_pm.c | 20 +++++---------------
For the i915 parts,
Acked-by: Jani Nikula <[email protected]>
for merging via whichever tree suits you best.
> include/linux/stackdepot.h | 3 +++
> lib/stackdepot.c | 23 +++++++++++++++++++++++
> mm/page_owner.c | 5 +----
> 7 files changed, 35 insertions(+), 31 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
> index 86d13d6bc463..2d1adab9e360 100644
> --- a/drivers/gpu/drm/drm_dp_mst_topology.c
> +++ b/drivers/gpu/drm/drm_dp_mst_topology.c
> @@ -1668,13 +1668,10 @@ __dump_topology_ref_history(struct drm_dp_mst_topology_ref_history *history,
> for (i = 0; i < history->len; i++) {
> const struct drm_dp_mst_topology_ref_entry *entry =
> &history->entries[i];
> - ulong *entries;
> - uint nr_entries;
> u64 ts_nsec = entry->ts_nsec;
> u32 rem_nsec = do_div(ts_nsec, 1000000000);
>
> - nr_entries = stack_depot_fetch(entry->backtrace, &entries);
> - stack_trace_snprint(buf, PAGE_SIZE, entries, nr_entries, 4);
> + stack_depot_snprint(entry->backtrace, buf, PAGE_SIZE, 4);
>
> drm_printf(&p, " %d %ss (last at %5llu.%06u):\n%s",
> entry->count,
> diff --git a/drivers/gpu/drm/drm_mm.c b/drivers/gpu/drm/drm_mm.c
> index 93d48a6f04ab..ca04d7f6f7b5 100644
> --- a/drivers/gpu/drm/drm_mm.c
> +++ b/drivers/gpu/drm/drm_mm.c
> @@ -118,8 +118,6 @@ static noinline void save_stack(struct drm_mm_node *node)
> static void show_leaks(struct drm_mm *mm)
> {
> struct drm_mm_node *node;
> - unsigned long *entries;
> - unsigned int nr_entries;
> char *buf;
>
> buf = kmalloc(BUFSZ, GFP_KERNEL);
> @@ -133,8 +131,7 @@ static void show_leaks(struct drm_mm *mm)
> continue;
> }
>
> - nr_entries = stack_depot_fetch(node->stack, &entries);
> - stack_trace_snprint(buf, BUFSZ, entries, nr_entries, 0);
> + stack_depot_snprint(node->stack, buf, BUFSZ);
> DRM_ERROR("node [%08llx + %08llx]: inserted at\n%s",
> node->start, node->size, buf);
> }
> diff --git a/drivers/gpu/drm/i915/i915_vma.c b/drivers/gpu/drm/i915/i915_vma.c
> index 4b7fc4647e46..f2d9ed375109 100644
> --- a/drivers/gpu/drm/i915/i915_vma.c
> +++ b/drivers/gpu/drm/i915/i915_vma.c
> @@ -56,8 +56,6 @@ void i915_vma_free(struct i915_vma *vma)
>
> static void vma_print_allocator(struct i915_vma *vma, const char *reason)
> {
> - unsigned long *entries;
> - unsigned int nr_entries;
> char buf[512];
>
> if (!vma->node.stack) {
> @@ -66,8 +64,7 @@ static void vma_print_allocator(struct i915_vma *vma, const char *reason)
> return;
> }
>
> - nr_entries = stack_depot_fetch(vma->node.stack, &entries);
> - stack_trace_snprint(buf, sizeof(buf), entries, nr_entries, 0);
> + stack_depot_snprint(vma->node.stack, buf, sizeof(buf), 0);
> DRM_DEBUG_DRIVER("vma.node [%08llx + %08llx] %s: inserted at %s\n",
> vma->node.start, vma->node.size, reason, buf);
> }
> diff --git a/drivers/gpu/drm/i915/intel_runtime_pm.c b/drivers/gpu/drm/i915/intel_runtime_pm.c
> index eaf7688f517d..cc312f0a05eb 100644
> --- a/drivers/gpu/drm/i915/intel_runtime_pm.c
> +++ b/drivers/gpu/drm/i915/intel_runtime_pm.c
> @@ -65,16 +65,6 @@ static noinline depot_stack_handle_t __save_depot_stack(void)
> return stack_depot_save(entries, n, GFP_NOWAIT | __GFP_NOWARN);
> }
>
> -static void __print_depot_stack(depot_stack_handle_t stack,
> - char *buf, int sz, int indent)
> -{
> - unsigned long *entries;
> - unsigned int nr_entries;
> -
> - nr_entries = stack_depot_fetch(stack, &entries);
> - stack_trace_snprint(buf, sz, entries, nr_entries, indent);
> -}
> -
> static void init_intel_runtime_pm_wakeref(struct intel_runtime_pm *rpm)
> {
> spin_lock_init(&rpm->debug.lock);
> @@ -146,12 +136,12 @@ static void untrack_intel_runtime_pm_wakeref(struct intel_runtime_pm *rpm,
> if (!buf)
> return;
>
> - __print_depot_stack(stack, buf, PAGE_SIZE, 2);
> + stack_depot_snprint(stack, buf, PAGE_SIZE, 2);
> DRM_DEBUG_DRIVER("wakeref %x from\n%s", stack, buf);
>
> stack = READ_ONCE(rpm->debug.last_release);
> if (stack) {
> - __print_depot_stack(stack, buf, PAGE_SIZE, 2);
> + stack_depot_snprint(stack, buf, PAGE_SIZE, 2);
> DRM_DEBUG_DRIVER("wakeref last released at\n%s", buf);
> }
>
> @@ -183,12 +173,12 @@ __print_intel_runtime_pm_wakeref(struct drm_printer *p,
> return;
>
> if (dbg->last_acquire) {
> - __print_depot_stack(dbg->last_acquire, buf, PAGE_SIZE, 2);
> + stack_depot_snprint(dbg->last_acquire, buf, PAGE_SIZE, 2);
> drm_printf(p, "Wakeref last acquired:\n%s", buf);
> }
>
> if (dbg->last_release) {
> - __print_depot_stack(dbg->last_release, buf, PAGE_SIZE, 2);
> + stack_depot_snprint(dbg->last_release, buf, PAGE_SIZE, 2);
> drm_printf(p, "Wakeref last released:\n%s", buf);
> }
>
> @@ -203,7 +193,7 @@ __print_intel_runtime_pm_wakeref(struct drm_printer *p,
> rep = 1;
> while (i + 1 < dbg->count && dbg->owners[i + 1] == stack)
> rep++, i++;
> - __print_depot_stack(stack, buf, PAGE_SIZE, 2);
> + stack_depot_print(stack, buf, PAGE_SIZE, 2);
> drm_printf(p, "Wakeref x%lu taken at:\n%s", rep, buf);
> }
>
> diff --git a/include/linux/stackdepot.h b/include/linux/stackdepot.h
> index d77a30543dd4..88b0b4cc9906 100644
> --- a/include/linux/stackdepot.h
> +++ b/include/linux/stackdepot.h
> @@ -19,6 +19,9 @@ depot_stack_handle_t stack_depot_save(unsigned long *entries,
> unsigned int stack_depot_fetch(depot_stack_handle_t handle,
> unsigned long **entries);
>
> +int stack_depot_snprint(depot_stack_handle_t handle, char *buf, size_t size,
> + int spaces);
> +
> void stack_depot_print(depot_stack_handle_t stack);
>
> unsigned int filter_irq_stacks(unsigned long *entries, unsigned int nr_entries);
> diff --git a/lib/stackdepot.c b/lib/stackdepot.c
> index 873aeb152f52..e1c1d7683f6b 100644
> --- a/lib/stackdepot.c
> +++ b/lib/stackdepot.c
> @@ -214,6 +214,29 @@ static inline struct stack_record *find_stack(struct stack_record *bucket,
> return NULL;
> }
>
> +/**
> + * stack_depot_snprint - print stack entries from a depot into a buffer
> + *
> + * @handle: Stack depot handle which was returned from
> + * stack_depot_save().
> + * @buf: Pointer to the print buffer
> + *
> + * @size: Size of the print buffer
> + *
> + * @spaces: Number of leading spaces to print
> + *
> + * Return: Number of bytes printed.
> + */
> +int stack_depot_snprint(depot_stack_handle_t handle, char *buf, size_t size,
> + int spaces)
> +{
> + unsigned long *entries;
> + unsigned int nr_entries;
> +
> + nr_entries = stack_depot_fetch(handle, &entries);
> + return stack_trace_snprint(buf, size, entries, nr_entries, 0);
> +}
> +
> /**
> * stack_depot_print - print stack entries from a depot
> *
> diff --git a/mm/page_owner.c b/mm/page_owner.c
> index 7918770c2b2b..a83f546c06b5 100644
> --- a/mm/page_owner.c
> +++ b/mm/page_owner.c
> @@ -329,8 +329,6 @@ print_page_owner(char __user *buf, size_t count, unsigned long pfn,
> depot_stack_handle_t handle)
> {
> int ret, pageblock_mt, page_mt;
> - unsigned long *entries;
> - unsigned int nr_entries;
> char *kbuf;
>
> count = min_t(size_t, count, PAGE_SIZE);
> @@ -361,8 +359,7 @@ print_page_owner(char __user *buf, size_t count, unsigned long pfn,
> if (ret >= count)
> goto err;
>
> - nr_entries = stack_depot_fetch(handle, &entries);
> - ret += stack_trace_snprint(kbuf + ret, count - ret, entries, nr_entries, 0);
> + ret += stack_depot_snprint(handle, kbuf + ret, count - ret, 0);
> if (ret >= count)
> goto err;
--
Jani Nikula, Intel Open Source Graphics Center