Commit 0f68d45e authored by Imran Khan's avatar Imran Khan Committed by Linus Torvalds
Browse files

lib, stackdepot: add helper to print stack entries into buffer 

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.

[imran.f.khan@oracle.com: fix build error]
  Link: https://lkml.kernel.org/r/20210915175321.3472770-4-imran.f.khan@oracle.com
[imran.f.khan@oracle.com: export stack_depot_snprint() to modules]
  Link: https://lkml.kernel.org/r/20210916133535.3592491-4-imran.f.khan@oracle.com

Link: https://lkml.kernel.org/r/20210915014806.3206938-4-imran.f.khan@oracle.com


Signed-off-by: default avatarImran Khan <imran.f.khan@oracle.com>
Suggested-by: default avatarVlastimil Babka <vbabka@suse.cz>
Acked-by: default avatarVlastimil Babka <vbabka@suse.cz>
Acked-by: Jani Nikula <jani.nikula@intel.com>	[i915]
Cc: 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: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 505be481

drivers/gpu/drm/drm_dp_mst_topology.c

+1 −4
Original line number Diff line number Diff line
@@ -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,

drivers/gpu/drm/drm_mm.c

+1 −4
Original line number Diff line number Diff line
@@ -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, 0);

		DRM_ERROR("node [%08llx + %08llx]: inserted at\n%s",

			  node->start, node->size, buf);

	}

drivers/gpu/drm/i915/i915_vma.c

+1 −4
Original line number Diff line number Diff line
@@ -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);

}

drivers/gpu/drm/i915/intel_runtime_pm.c

+5 −15
Original line number Diff line number Diff line
@@ -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_snprint(stack, buf, PAGE_SIZE, 2);

		drm_printf(p, "Wakeref x%lu taken at:\n%s", rep, buf);

	}

include/linux/stackdepot.h

+3 −0
Original line number Diff line number Diff line
@@ -25,6 +25,9 @@ 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);



#ifdef CONFIG_STACKDEPOT