The patch titled Subject: lib/stackdepot: store next pool pointer in new_pool has been added to the -mm mm-unstable branch. Its filename is lib-stackdepot-store-next-pool-pointer-in-new_pool.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/lib-stackdepot-store-next-pool-pointer-in-new_pool.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Andrey Konovalov <andreyknvl@xxxxxxxxxx> Subject: lib/stackdepot: store next pool pointer in new_pool Date: Wed, 13 Sep 2023 19:14:34 +0200 Instead of using the last pointer in stack_pools for storing the pointer to a new pool (which does not yet store any stack records), use a new new_pool variable. This a purely code readability change: it seems more logical to store the pointer to a pool with a special meaning in a dedicated variable. Link: https://lkml.kernel.org/r/3a7056408e391ff0c66b5f50c460a7b9f796228f.1694625260.git.andreyknvl@xxxxxxxxxx Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx> Cc: Alexander Potapenko <glider@xxxxxxxxxx> Cc: Andrey Konovalov <andreyknvl@xxxxxxxxx> Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx> Cc: Evgenii Stepanov <eugenis@xxxxxxxxxx> Cc: Marco Elver <elver@xxxxxxxxxx> Cc: Oscar Salvador <osalvador@xxxxxxx> Cc: Vlastimil Babka <vbabka@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- lib/stackdepot.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) --- a/lib/stackdepot.c~lib-stackdepot-store-next-pool-pointer-in-new_pool +++ a/lib/stackdepot.c @@ -85,6 +85,8 @@ static unsigned int stack_hash_mask; /* Array of memory regions that store stack traces. */ static void *stack_pools[DEPOT_MAX_POOLS]; +/* Newly allocated pool that is not yet added to stack_pools. */ +static void *new_pool; /* Currently used pool in stack_pools. */ static int pool_index; /* Offset to the unused space in the currently used pool. */ @@ -233,7 +235,7 @@ static void depot_keep_new_pool(void **p * as long as we do not exceed the maximum number of pools. */ if (pool_index + 1 < DEPOT_MAX_POOLS) { - stack_pools[pool_index + 1] = *prealloc; + new_pool = *prealloc; *prealloc = NULL; } @@ -263,6 +265,8 @@ static bool depot_update_pools(size_t re * stack_depot_fetch. */ WRITE_ONCE(pool_index, pool_index + 1); + stack_pools[pool_index] = new_pool; + new_pool = NULL; pool_offset = 0; /* _ Patches currently in -mm which might be from andreyknvl@xxxxxxxxxx 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