From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id AA606EE0207 for ; Wed, 13 Sep 2023 19:28:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232416AbjIMT2n (ORCPT ); Wed, 13 Sep 2023 15:28:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41532 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232403AbjIMT2m (ORCPT ); Wed, 13 Sep 2023 15:28:42 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DF4A819AD for ; Wed, 13 Sep 2023 12:28:37 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7653DC433CA; Wed, 13 Sep 2023 19:28:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1694633317; bh=mnvvFRt5YblOs6Ii7/27kWBnsI/Nv9cf6g9YQJqQQ48=; h=Date:To:From:Subject:From; b=s1np3RNu9nsgjI2zawrS1us/DDQ/zDYH8AceaxdjwPDKkMxQm2X8Q78UBXZWkCLXz L57t90so58I3y2UFQ2WwZhTEtXWLjaEMmn2snaW0j4zwc/cbcq62nY6SQakRQjPtmv VUahpUB1Z3i/AX885h6+ogqks82xgoX5raKl4quE= Date: Wed, 13 Sep 2023 12:28:36 -0700 To: mm-commits@vger.kernel.org, vbabka@suse.cz, osalvador@suse.de, glider@google.com, eugenis@google.com, elver@google.com, dvyukov@google.com, andreyknvl@gmail.com, andreyknvl@google.com, akpm@linux-foundation.org From: Andrew Morton Subject: + lib-stackdepot-add-depot_fetch_stack-helper.patch added to mm-unstable branch Message-Id: <20230913192837.7653DC433CA@smtp.kernel.org> Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org The patch titled Subject: lib/stackdepot: add depot_fetch_stack helper has been added to the -mm mm-unstable branch. Its filename is lib-stackdepot-add-depot_fetch_stack-helper.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/lib-stackdepot-add-depot_fetch_stack-helper.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 Subject: lib/stackdepot: add depot_fetch_stack helper Date: Wed, 13 Sep 2023 19:14:29 +0200 Add a helper depot_fetch_stack function that fetches the pointer to a stack record. With this change, all static depot_* functions now operate on stack pools and the exported stack_depot_* functions operate on the hash table. Link: https://lkml.kernel.org/r/74e0a28a38b05f27f3a4b54d5fa93213672fcd30.1694625260.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov Reviewed-by: Alexander Potapenko Cc: Andrey Konovalov Cc: Dmitry Vyukov Cc: Evgenii Stepanov Cc: Marco Elver Cc: Oscar Salvador Cc: Vlastimil Babka Signed-off-by: Andrew Morton --- lib/stackdepot.c | 45 ++++++++++++++++++++++++++++----------------- 1 file changed, 28 insertions(+), 17 deletions(-) --- a/lib/stackdepot.c~lib-stackdepot-add-depot_fetch_stack-helper +++ a/lib/stackdepot.c @@ -304,6 +304,7 @@ depot_alloc_stack(unsigned long *entries stack->handle.extra = 0; memcpy(stack->entries, entries, flex_array_size(stack, entries, size)); pool_offset += required_size; + /* * Let KMSAN know the stored stack record is initialized. This shall * prevent false positive reports if instrumented code accesses it. @@ -313,6 +314,32 @@ depot_alloc_stack(unsigned long *entries return stack; } +static struct stack_record *depot_fetch_stack(depot_stack_handle_t handle) +{ + union handle_parts parts = { .handle = handle }; + /* + * READ_ONCE pairs with potential concurrent write in + * depot_alloc_stack(). + */ + int pool_index_cached = READ_ONCE(pool_index); + void *pool; + size_t offset = parts.offset << DEPOT_STACK_ALIGN; + struct stack_record *stack; + + if (parts.pool_index > pool_index_cached) { + WARN(1, "pool index %d out of bounds (%d) for stack id %08x\n", + parts.pool_index, pool_index_cached, handle); + return NULL; + } + + pool = stack_pools[parts.pool_index]; + if (!pool) + return NULL; + + stack = pool + offset; + return stack; +} + /* Calculates the hash for a stack. */ static inline u32 hash_stack(unsigned long *entries, unsigned int size) { @@ -456,14 +483,6 @@ EXPORT_SYMBOL_GPL(stack_depot_save); unsigned int stack_depot_fetch(depot_stack_handle_t handle, unsigned long **entries) { - union handle_parts parts = { .handle = handle }; - /* - * READ_ONCE pairs with potential concurrent write in - * depot_alloc_stack. - */ - int pool_index_cached = READ_ONCE(pool_index); - void *pool; - size_t offset = parts.offset << DEPOT_STACK_ALIGN; struct stack_record *stack; *entries = NULL; @@ -476,15 +495,7 @@ unsigned int stack_depot_fetch(depot_sta if (!handle || stack_depot_disabled) return 0; - if (parts.pool_index > pool_index_cached) { - WARN(1, "pool index %d out of bounds (%d) for stack id %08x\n", - parts.pool_index, pool_index_cached, handle); - return 0; - } - pool = stack_pools[parts.pool_index]; - if (!pool) - return 0; - stack = pool + offset; + stack = depot_fetch_stack(handle); *entries = stack->entries; return stack->size; _ 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