From patchwork Thu Apr 18 08:41:22 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Gleixner X-Patchwork-Id: 10906759 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 5039A1850 for ; Thu, 18 Apr 2019 09:07:00 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3C4D928857 for ; Thu, 18 Apr 2019 09:07:00 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 30325289DA; Thu, 18 Apr 2019 09:07:00 +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=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9E0BD28857 for ; Thu, 18 Apr 2019 09:06:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388378AbfDRJGv (ORCPT ); Thu, 18 Apr 2019 05:06:51 -0400 Received: from Galois.linutronix.de ([146.0.238.70]:33655 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388343AbfDRJGu (ORCPT ); Thu, 18 Apr 2019 05:06:50 -0400 Received: from localhost ([127.0.0.1] helo=nanos.tec.linutronix.de) by Galois.linutronix.de with esmtp (Exim 4.80) (envelope-from ) id 1hH2zc-0001m4-W3; Thu, 18 Apr 2019 11:06:05 +0200 Message-Id: <20190418084253.337266121@linutronix.de> User-Agent: quilt/0.65 Date: Thu, 18 Apr 2019 10:41:22 +0200 From: Thomas Gleixner To: LKML Cc: Josh Poimboeuf , x86@kernel.org, Andy Lutomirski , Steven Rostedt , Alexander Potapenko , Alexey Dobriyan , Andrew Morton , Pekka Enberg , linux-mm@kvack.org, David Rientjes , Christoph Lameter , Catalin Marinas , Dmitry Vyukov , Andrey Ryabinin , kasan-dev@googlegroups.com, Mike Rapoport , Akinobu Mita , iommu@lists.linux-foundation.org, Robin Murphy , Christoph Hellwig , Marek Szyprowski , Johannes Thumshirn , David Sterba , Chris Mason , Josef Bacik , linux-btrfs@vger.kernel.org, dm-devel@redhat.com, Mike Snitzer , Alasdair Kergon , intel-gfx@lists.freedesktop.org, Joonas Lahtinen , Maarten Lankhorst , dri-devel@lists.freedesktop.org, David Airlie , Jani Nikula , Daniel Vetter , Rodrigo Vivi , linux-arch@vger.kernel.org Subject: [patch V2 03/29] lib/stackdepot: Provide functions which operate on plain storage arrays References: <20190418084119.056416939@linutronix.de> MIME-Version: 1.0 Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org 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 --- include/linux/stackdepot.h | 4 ++ lib/stackdepot.c | 66 ++++++++++++++++++++++++++++++++------------- 2 files changed, 51 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 +194,56 @@ 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 + * + * @entries: Pointer to store the entries address + */ +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 * - * Returns the handle of the stack struct stored in depot. + * @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 */ -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 +251,8 @@ 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 +280,10 @@ 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 +313,16 @@ 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);