From 0f68d45ef41abb618a9ca33996348ae73800a106 Mon Sep 17 00:00:00 2001
From: Imran Khan <imran.f.khan@oracle.com>
Date: Mon, 8 Nov 2021 18:33:16 -0800
Subject: [PATCH] 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: Imran Khan <imran.f.khan@oracle.com>
Suggested-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Vlastimil 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: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
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 | 25 +++++++++++++++++++++++++
mm/page_owner.c | 5 +----
7 files changed, 37 insertions(+), 31 deletions(-)
diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
index 86d13d6bc4631..2d1adab9e3600 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 93d48a6f04abe..7d1c578388d33 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, 0);
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 4b7fc4647e460..f2d9ed3751093 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 eaf7688f517d0..0d85f3c5c5266 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_snprint(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 8ab37500fcba8..c34b55a6e5540 100644
--- a/include/linux/stackdepot.h
+++ b/include/linux/stackdepot.h
@@ -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
diff --git a/lib/stackdepot.c b/lib/stackdepot.c
index 4e1f2982d0fa7..b437ae79aca14 100644
--- a/lib/stackdepot.c
+++ b/lib/stackdepot.c
@@ -213,6 +213,31 @@ 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 nr_entries ? stack_trace_snprint(buf, size, entries, nr_entries,
+ spaces) : 0;
+}
+EXPORT_SYMBOL_GPL(stack_depot_snprint);
+
/**
* stack_depot_print - print stack entries from a depot
*
diff --git a/mm/page_owner.c b/mm/page_owner.c
index eff29be1218bc..1653040d1133a 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;
--
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