From patchwork Thu Apr 25 09:44:56 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Gleixner X-Patchwork-Id: 10918507 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 08BE092A for ; Fri, 26 Apr 2019 07:10:50 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E949C28D9C for ; Fri, 26 Apr 2019 07:10:49 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id DC93628D9F; Fri, 26 Apr 2019 07:10:49 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=unavailable version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 82FB828D9C for ; Fri, 26 Apr 2019 07:10:49 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id EF57389622; Fri, 26 Apr 2019 07:10:29 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from Galois.linutronix.de (Galois.linutronix.de [IPv6:2a01:7a0:2:106d:700::1]) by gabe.freedesktop.org (Postfix) with ESMTPS id 76E5F8925B; Thu, 25 Apr 2019 10:00:55 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=nanos.tec.linutronix.de) by Galois.linutronix.de with esmtp (Exim 4.80) (envelope-from ) id 1hJb9m-0001qd-PK; Thu, 25 Apr 2019 11:59:06 +0200 Message-Id: <20190425094801.414574828@linutronix.de> User-Agent: quilt/0.65 Date: Thu, 25 Apr 2019 11:44:56 +0200 From: Thomas Gleixner To: LKML Subject: [patch V3 03/29] lib/stackdepot: Provide functions which operate on plain storage arrays References: <20190425094453.875139013@linutronix.de> MIME-Version: 1.0 X-Mailman-Approved-At: Fri, 26 Apr 2019 07:08:59 +0000 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mike Snitzer , David Airlie , Catalin Marinas , dri-devel@lists.freedesktop.org, linux-mm@kvack.org, dm-devel@redhat.com, Alexander Potapenko , Christoph Lameter , Miroslav Benes , Christoph Hellwig , Alasdair Kergon , Marek Szyprowski , linux-arch@vger.kernel.org, x86@kernel.org, kasan-dev@googlegroups.com, Johannes Thumshirn , Andrey Ryabinin , Alexey Dobriyan , intel-gfx@lists.freedesktop.org, David Rientjes , Akinobu Mita , Steven Rostedt , Josef Bacik , Rodrigo Vivi , Mike Rapoport , Andy Lutomirski , Josh Poimboeuf , David Sterba , Dmitry Vyukov , Tom Zanussi , Chris Mason , Pekka Enberg , iommu@lists.linux-foundation.org, Andrew Morton , Robin Murphy , linux-btrfs@vger.kernel.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP The struct stack_trace indirection in the stack depot functions is a truly pointless excercise which requires horrible code at the callsites. Provide interfaces based on plain storage arrays. Signed-off-by: Thomas Gleixner Acked-by: Alexander Potapenko --- V3: Fix kernel-doc --- include/linux/stackdepot.h | 4 ++ lib/stackdepot.c | 70 ++++++++++++++++++++++++++++++++------------- 2 files changed, 55 insertions(+), 19 deletions(-) --- a/include/linux/stackdepot.h +++ b/include/linux/stackdepot.h @@ -26,7 +26,11 @@ typedef u32 depot_stack_handle_t; struct stack_trace; depot_stack_handle_t depot_save_stack(struct stack_trace *trace, gfp_t flags); +depot_stack_handle_t stack_depot_save(unsigned long *entries, + unsigned int nr_entries, gfp_t gfp_flags); void depot_fetch_stack(depot_stack_handle_t handle, struct stack_trace *trace); +unsigned int stack_depot_fetch(depot_stack_handle_t handle, + unsigned long **entries); #endif --- a/lib/stackdepot.c +++ b/lib/stackdepot.c @@ -194,40 +194,60 @@ static inline struct stack_record *find_ return NULL; } -void depot_fetch_stack(depot_stack_handle_t handle, struct stack_trace *trace) +/** + * stack_depot_fetch - Fetch stack entries from a depot + * + * @handle: Stack depot handle which was returned from + * stack_depot_save(). + * @entries: Pointer to store the entries address + * + * Return: The number of trace entries for this depot. + */ +unsigned int stack_depot_fetch(depot_stack_handle_t handle, + unsigned long **entries) { union handle_parts parts = { .handle = handle }; void *slab = stack_slabs[parts.slabindex]; size_t offset = parts.offset << STACK_ALLOC_ALIGN; struct stack_record *stack = slab + offset; - trace->nr_entries = trace->max_entries = stack->size; - trace->entries = stack->entries; - trace->skip = 0; + *entries = stack->entries; + return stack->size; +} +EXPORT_SYMBOL_GPL(stack_depot_fetch); + +void depot_fetch_stack(depot_stack_handle_t handle, struct stack_trace *trace) +{ + unsigned int nent = stack_depot_fetch(handle, &trace->entries); + + trace->max_entries = trace->nr_entries = nent; } EXPORT_SYMBOL_GPL(depot_fetch_stack); /** - * depot_save_stack - save stack in a stack depot. - * @trace - the stacktrace to save. - * @alloc_flags - flags for allocating additional memory if required. + * stack_depot_save - Save a stack trace from an array + * + * @entries: Pointer to storage array + * @nr_entries: Size of the storage array + * @alloc_flags: Allocation gfp flags * - * Returns the handle of the stack struct stored in depot. + * Return: The handle of the stack struct stored in depot */ -depot_stack_handle_t depot_save_stack(struct stack_trace *trace, - gfp_t alloc_flags) +depot_stack_handle_t stack_depot_save(unsigned long *entries, + unsigned int nr_entries, + gfp_t alloc_flags) { - u32 hash; - depot_stack_handle_t retval = 0; struct stack_record *found = NULL, **bucket; - unsigned long flags; + depot_stack_handle_t retval = 0; struct page *page = NULL; void *prealloc = NULL; + unsigned long flags; + u32 hash; - if (unlikely(trace->nr_entries == 0)) + if (unlikely(nr_entries == 0)) goto fast_exit; - hash = hash_stack(trace->entries, trace->nr_entries); + hash = hash_stack(entries, nr_entries); bucket = &stack_table[hash & STACK_HASH_MASK]; /* @@ -235,8 +255,8 @@ depot_stack_handle_t depot_save_stack(st * The smp_load_acquire() here pairs with smp_store_release() to * |bucket| below. */ - found = find_stack(smp_load_acquire(bucket), trace->entries, - trace->nr_entries, hash); + found = find_stack(smp_load_acquire(bucket), entries, + nr_entries, hash); if (found) goto exit; @@ -264,10 +284,10 @@ depot_stack_handle_t depot_save_stack(st spin_lock_irqsave(&depot_lock, flags); - found = find_stack(*bucket, trace->entries, trace->nr_entries, hash); + found = find_stack(*bucket, entries, nr_entries, hash); if (!found) { struct stack_record *new = - depot_alloc_stack(trace->entries, trace->nr_entries, + depot_alloc_stack(entries, nr_entries, hash, &prealloc, alloc_flags); if (new) { new->next = *bucket; @@ -297,4 +317,16 @@ depot_stack_handle_t depot_save_stack(st fast_exit: return retval; } +EXPORT_SYMBOL_GPL(stack_depot_save); + +/** + * depot_save_stack - save stack in a stack depot. + * @trace - the stacktrace to save. + * @alloc_flags - flags for allocating additional memory if required. + */ +depot_stack_handle_t depot_save_stack(struct stack_trace *trace, + gfp_t alloc_flags) +{ + return stack_depot_save(trace->entries, trace->nr_entries, alloc_flags); +} EXPORT_SYMBOL_GPL(depot_save_stack);