This is a note to let you know that I've just added the patch titled
lib/stackdepot: move stack_record struct definition into the header
to the 6.8-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
lib-stackdepot-move-stack_record-struct-definition-i.patch
and it can be found in the queue-6.8 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 4c6bcd6022e1b5208d4561274e7077ab8bec16ce
Author: Oscar Salvador <osalvador@xxxxxxx>
Date: Thu Feb 15 22:59:02 2024 +0100
lib/stackdepot: move stack_record struct definition into the header
[ Upstream commit 8151c7a35d8bd8a12e93538ef7963ea209b6ab41 ]
In order to move the heavy lifting into page_owner code, this one needs to
have access to the stack_record structure, which right now sits in
lib/stackdepot.c. Move it to the stackdepot.h header so page_owner can
access stack_record's struct fields.
Link: https://lkml.kernel.org/r/20240215215907.20121-3-osalvador@xxxxxxx
Signed-off-by: Oscar Salvador <osalvador@xxxxxxx>
Reviewed-by: Marco Elver <elver@xxxxxxxxxx>
Reviewed-by: Vlastimil Babka <vbabka@xxxxxxx>
Acked-by: Andrey Konovalov <andreyknvl@xxxxxxxxx>
Cc: Alexander Potapenko <glider@xxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Stable-dep-of: a6c1d9cb9a68 ("stackdepot: rename pool_index to pool_index_plus_1")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/include/linux/stackdepot.h b/include/linux/stackdepot.h
index adcbb8f236000..c4b5ad57c0660 100644
--- a/include/linux/stackdepot.h
+++ b/include/linux/stackdepot.h
@@ -30,6 +30,53 @@ typedef u32 depot_stack_handle_t;
*/
#define STACK_DEPOT_EXTRA_BITS 5
+#define DEPOT_HANDLE_BITS (sizeof(depot_stack_handle_t) * 8)
+
+#define DEPOT_POOL_ORDER 2 /* Pool size order, 4 pages */
+#define DEPOT_POOL_SIZE (1LL << (PAGE_SHIFT + DEPOT_POOL_ORDER))
+#define DEPOT_STACK_ALIGN 4
+#define DEPOT_OFFSET_BITS (DEPOT_POOL_ORDER + PAGE_SHIFT - DEPOT_STACK_ALIGN)
+#define DEPOT_POOL_INDEX_BITS (DEPOT_HANDLE_BITS - DEPOT_OFFSET_BITS - \
+ STACK_DEPOT_EXTRA_BITS)
+
+#ifdef CONFIG_STACKDEPOT
+/* Compact structure that stores a reference to a stack. */
+union handle_parts {
+ depot_stack_handle_t handle;
+ struct {
+ /* pool_index is offset by 1 */
+ u32 pool_index : DEPOT_POOL_INDEX_BITS;
+ u32 offset : DEPOT_OFFSET_BITS;
+ u32 extra : STACK_DEPOT_EXTRA_BITS;
+ };
+};
+
+struct stack_record {
+ struct list_head hash_list; /* Links in the hash table */
+ u32 hash; /* Hash in hash table */
+ u32 size; /* Number of stored frames */
+ union handle_parts handle; /* Constant after initialization */
+ refcount_t count;
+ union {
+ unsigned long entries[CONFIG_STACKDEPOT_MAX_FRAMES]; /* Frames */
+ struct {
+ /*
+ * An important invariant of the implementation is to
+ * only place a stack record onto the freelist iff its
+ * refcount is zero. Because stack records with a zero
+ * refcount are never considered as valid, it is safe to
+ * union @entries and freelist management state below.
+ * Conversely, as soon as an entry is off the freelist
+ * and its refcount becomes non-zero, the below must not
+ * be accessed until being placed back on the freelist.
+ */
+ struct list_head free_list; /* Links in the freelist */
+ unsigned long rcu_state; /* RCU cookie */
+ };
+ };
+};
+#endif
+
typedef u32 depot_flags_t;
/*
diff --git a/lib/stackdepot.c b/lib/stackdepot.c
index c1ec2b4b6dabf..ee4bbe6513aa4 100644
--- a/lib/stackdepot.c
+++ b/lib/stackdepot.c
@@ -36,55 +36,12 @@
#include <linux/memblock.h>
#include <linux/kasan-enabled.h>
-#define DEPOT_HANDLE_BITS (sizeof(depot_stack_handle_t) * 8)
-
-#define DEPOT_POOL_ORDER 2 /* Pool size order, 4 pages */
-#define DEPOT_POOL_SIZE (1LL << (PAGE_SHIFT + DEPOT_POOL_ORDER))
-#define DEPOT_STACK_ALIGN 4
-#define DEPOT_OFFSET_BITS (DEPOT_POOL_ORDER + PAGE_SHIFT - DEPOT_STACK_ALIGN)
-#define DEPOT_POOL_INDEX_BITS (DEPOT_HANDLE_BITS - DEPOT_OFFSET_BITS - \
- STACK_DEPOT_EXTRA_BITS)
#define DEPOT_POOLS_CAP 8192
/* The pool_index is offset by 1 so the first record does not have a 0 handle. */
#define DEPOT_MAX_POOLS \
(((1LL << (DEPOT_POOL_INDEX_BITS)) - 1 < DEPOT_POOLS_CAP) ? \
(1LL << (DEPOT_POOL_INDEX_BITS)) - 1 : DEPOT_POOLS_CAP)
-/* Compact structure that stores a reference to a stack. */
-union handle_parts {
- depot_stack_handle_t handle;
- struct {
- u32 pool_index : DEPOT_POOL_INDEX_BITS; /* pool_index is offset by 1 */
- u32 offset : DEPOT_OFFSET_BITS;
- u32 extra : STACK_DEPOT_EXTRA_BITS;
- };
-};
-
-struct stack_record {
- struct list_head hash_list; /* Links in the hash table */
- u32 hash; /* Hash in hash table */
- u32 size; /* Number of stored frames */
- union handle_parts handle; /* Constant after initialization */
- refcount_t count;
- union {
- unsigned long entries[CONFIG_STACKDEPOT_MAX_FRAMES]; /* Frames */
- struct {
- /*
- * An important invariant of the implementation is to
- * only place a stack record onto the freelist iff its
- * refcount is zero. Because stack records with a zero
- * refcount are never considered as valid, it is safe to
- * union @entries and freelist management state below.
- * Conversely, as soon as an entry is off the freelist
- * and its refcount becomes non-zero, the below must not
- * be accessed until being placed back on the freelist.
- */
- struct list_head free_list; /* Links in the freelist */
- unsigned long rcu_state; /* RCU cookie */
- };
- };
-};
-
static bool stack_depot_disabled;
static bool __stack_depot_early_init_requested __initdata = IS_ENABLED(CONFIG_STACKDEPOT_ALWAYS_INIT);
static bool __stack_depot_early_init_passed __initdata;
