[tip:core/stacktrace] mm/kmemleak: Simplify stacktrace handling

[tip-bot for Thomas Gleixner]

Commit-ID:  07984aad1c7ed679596f849c0e7d5e029f76e0eb
Gitweb:     https://git.kernel.org/tip/07984aad1c7ed679596f849c0e7d5e029f76e0eb
Author:     Thomas Gleixner <tglx@xxxxxxxxxxxxx>
AuthorDate: Thu, 25 Apr 2019 11:45:01 +0200
Committer:  Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitDate: Mon, 29 Apr 2019 12:37:49 +0200

mm/kmemleak: Simplify stacktrace handling

Replace the indirection through struct stack_trace by using the storage
array based interfaces.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Reviewed-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
Acked-by: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxx>
Cc: linux-mm@xxxxxxxxx
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
Cc: Alexander Potapenko <glider@xxxxxxxxxx>
Cc: Alexey Dobriyan <adobriyan@xxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Christoph Lameter <cl@xxxxxxxxx>
Cc: Pekka Enberg <penberg@xxxxxxxxxx>
Cc: David Rientjes <rientjes@xxxxxxxxxx>
Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
Cc: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx>
Cc: kasan-dev@xxxxxxxxxxxxxxxx
Cc: Mike Rapoport <rppt@xxxxxxxxxxxxxxxxxx>
Cc: Akinobu Mita <akinobu.mita@xxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: iommu@xxxxxxxxxxxxxxxxxxxxxxxxxx
Cc: Robin Murphy <robin.murphy@xxxxxxx>
Cc: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
Cc: Johannes Thumshirn <jthumshirn@xxxxxxx>
Cc: David Sterba <dsterba@xxxxxxxx>
Cc: Chris Mason <clm@xxxxxx>
Cc: Josef Bacik <josef@xxxxxxxxxxxxxx>
Cc: linux-btrfs@xxxxxxxxxxxxxxx
Cc: dm-devel@xxxxxxxxxx
Cc: Mike Snitzer <snitzer@xxxxxxxxxx>
Cc: Alasdair Kergon <agk@xxxxxxxxxx>
Cc: Daniel Vetter <daniel@xxxxxxxx>
Cc: intel-gfx@xxxxxxxxxxxxxxxxxxxxx
Cc: Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx>
Cc: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx>
Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx
Cc: David Airlie <airlied@xxxxxxxx>
Cc: Jani Nikula <jani.nikula@xxxxxxxxxxxxxxx>
Cc: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx>
Cc: Tom Zanussi <tom.zanussi@xxxxxxxxxxxxxxx>
Cc: Miroslav Benes <mbenes@xxxxxxx>
Cc: linux-arch@xxxxxxxxxxxxxxx
Link: https://lkml.kernel.org/r/20190425094801.863716911@xxxxxxxxxxxxx

---
 mm/kmemleak.c | 24 +++---------------------
 1 file changed, 3 insertions(+), 21 deletions(-)

diff --git a/mm/kmemleak.c b/mm/kmemleak.c
index 6c318f5ac234..d12b35de1e7e 100644
--- a/mm/kmemleak.c
+++ b/mm/kmemleak.c
@@ -410,11 +410,6 @@ static void print_unreferenced(struct seq_file *seq,
  */
 static void dump_object_info(struct kmemleak_object *object)
 {
-	struct stack_trace trace;
-
-	trace.nr_entries = object->trace_len;
-	trace.entries = object->trace;
-
 	pr_notice("Object 0x%08lx (size %zu):\n",
 		  object->pointer, object->size);
 	pr_notice("  comm \"%s\", pid %d, jiffies %lu\n",
@@ -424,7 +419,7 @@ static void dump_object_info(struct kmemleak_object *object)
 	pr_notice("  flags = 0x%x\n", object->flags);
 	pr_notice("  checksum = %u\n", object->checksum);
 	pr_notice("  backtrace:\n");
-	print_stack_trace(&trace, 4);
+	stack_trace_print(object->trace, object->trace_len, 4);
 }
 
 /*
@@ -553,15 +548,7 @@ static struct kmemleak_object *find_and_remove_object(unsigned long ptr, int ali
  */
 static int __save_stack_trace(unsigned long *trace)
 {
-	struct stack_trace stack_trace;
-
-	stack_trace.max_entries = MAX_TRACE;
-	stack_trace.nr_entries = 0;
-	stack_trace.entries = trace;
-	stack_trace.skip = 2;
-	save_stack_trace(&stack_trace);
-
-	return stack_trace.nr_entries;
+	return stack_trace_save(trace, MAX_TRACE, 2);
 }
 
 /*
@@ -2019,13 +2006,8 @@ early_param("kmemleak", kmemleak_boot_config);
 
 static void __init print_log_trace(struct early_log *log)
 {
-	struct stack_trace trace;
-
-	trace.nr_entries = log->trace_len;
-	trace.entries = log->trace;
-
 	pr_notice("Early log backtrace:\n");
-	print_stack_trace(&trace, 2);
+	stack_trace_print(log->trace, log->trace_len, 2);
 }
 
 /*