+ lib-stackdepot-simplify-__stack_depot_save.patch added to mm-unstable branch

[Andrew Morton <akpm@linux-foundation.org>]

The patch titled
     Subject: lib/stackdepot: simplify __stack_depot_save
has been added to the -mm mm-unstable branch.  Its filename is
     lib-stackdepot-simplify-__stack_depot_save.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/lib-stackdepot-simplify-__stack_depot_save.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Andrey Konovalov <andreyknvl@google.com>
Subject: lib/stackdepot: simplify __stack_depot_save
Date: Wed, 13 Sep 2023 19:14:27 +0200

The retval local variable in __stack_depot_save has the union type
handle_parts, but the function never uses anything but the union's handle
field.

Define retval simply as depot_stack_handle_t to simplify the code.

Link: https://lkml.kernel.org/r/3336cf19b8e53ed5449550a085cff9bddec4c873.1694625260.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Marco Elver <elver@google.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 lib/stackdepot.c |    9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

--- a/lib/stackdepot.c~lib-stackdepot-simplify-__stack_depot_save
+++ a/lib/stackdepot.c
@@ -360,7 +360,7 @@ depot_stack_handle_t __stack_depot_save(
 					gfp_t alloc_flags, bool can_alloc)
 {
 	struct stack_record *found = NULL, **bucket;
-	union handle_parts retval = { .handle = 0 };
+	depot_stack_handle_t handle = 0;
 	struct page *page = NULL;
 	void *prealloc = NULL;
 	unsigned long flags;
@@ -377,7 +377,7 @@ depot_stack_handle_t __stack_depot_save(
 	nr_entries = filter_irq_stacks(entries, nr_entries);
 
 	if (unlikely(nr_entries == 0) || stack_depot_disabled)
-		goto fast_exit;
+		return 0;
 
 	hash = hash_stack(entries, nr_entries);
 	bucket = &stack_table[hash & stack_hash_mask];
@@ -443,9 +443,8 @@ exit:
 		free_pages((unsigned long)prealloc, DEPOT_POOL_ORDER);
 	}
 	if (found)
-		retval.handle = found->handle.handle;
-fast_exit:
-	return retval.handle;
+		handle = found->handle.handle;
+	return handle;
 }
 EXPORT_SYMBOL_GPL(__stack_depot_save);
 
_

Patches currently in -mm which might be from andreyknvl@google.com are

lib-stackdepot-check-disabled-flag-when-fetching.patch
lib-stackdepot-simplify-__stack_depot_save.patch
lib-stackdepot-drop-valid-bit-from-handles.patch
lib-stackdepot-add-depot_fetch_stack-helper.patch
lib-stackdepot-use-fixed-sized-slots-for-stack-records.patch
lib-stackdepot-fix-and-clean-up-atomic-annotations.patch
lib-stackdepot-rework-helpers-for-depot_alloc_stack.patch
lib-stackdepot-rename-next_pool_required-to-new_pool_required.patch
lib-stackdepot-store-next-pool-pointer-in-new_pool.patch
lib-stackdepot-store-free-stack-records-in-a-freelist.patch
lib-stackdepot-use-read-write-lock.patch
lib-stackdepot-use-list_head-for-stack-record-links.patch
kmsan-use-stack_depot_save-instead-of-__stack_depot_save.patch
lib-stackdepot-kasan-add-flags-to-__stack_depot_save-and-rename.patch
lib-stackdepot-add-refcount-for-records.patch
lib-stackdepot-allow-users-to-evict-stack-traces.patch
kasan-remove-atomic-accesses-to-stack-ring-entries.patch
kasan-check-object_size-in-kasan_complete_mode_report_info.patch
kasan-use-stack_depot_put-for-tag-based-modes.patch