From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752433AbaEBNmK (ORCPT ); Fri, 2 May 2014 09:42:10 -0400 Received: from fw-tnat.cambridge.arm.com ([217.140.96.21]:52224 "EHLO cam-smtp0.cambridge.arm.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752261AbaEBNlv (ORCPT ); Fri, 2 May 2014 09:41:51 -0400 From: Catalin Marinas To: linux-kernel@vger.kernel.org, linux-mm@kvack.org Cc: Andrew Morton , Johannes Weiner Subject: [PATCH 2/6] mm: Introduce kmemleak_update_trace() Date: Fri, 2 May 2014 14:41:06 +0100 Message-Id: <1399038070-1540-3-git-send-email-catalin.marinas@arm.com> X-Mailer: git-send-email 1.7.12.3 In-Reply-To: <1399038070-1540-1-git-send-email-catalin.marinas@arm.com> References: <1399038070-1540-1-git-send-email-catalin.marinas@arm.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The memory allocation stack trace is not always useful for debugging a memory leak (e.g. radix_tree_preload). This function, when called, updates the stack trace for an already allocated object. Signed-off-by: Catalin Marinas Cc: Andrew Morton Cc: Johannes Weiner --- Documentation/kmemleak.txt | 1 + include/linux/kmemleak.h | 4 ++++ mm/kmemleak.c | 34 ++++++++++++++++++++++++++++++++++ 3 files changed, 39 insertions(+) diff --git a/Documentation/kmemleak.txt b/Documentation/kmemleak.txt index a7563ec4ea7b..b772418bf064 100644 --- a/Documentation/kmemleak.txt +++ b/Documentation/kmemleak.txt @@ -142,6 +142,7 @@ kmemleak_alloc_percpu - notify of a percpu memory block allocation kmemleak_free - notify of a memory block freeing kmemleak_free_part - notify of a partial memory block freeing kmemleak_free_percpu - notify of a percpu memory block freeing +kmemleak_update_trace - update object allocation stack trace kmemleak_not_leak - mark an object as not a leak kmemleak_ignore - do not scan or report an object as leak kmemleak_scan_area - add scan areas inside a memory block diff --git a/include/linux/kmemleak.h b/include/linux/kmemleak.h index 5bb424659c04..057e95971014 100644 --- a/include/linux/kmemleak.h +++ b/include/linux/kmemleak.h @@ -30,6 +30,7 @@ extern void kmemleak_alloc_percpu(const void __percpu *ptr, size_t size) __ref; extern void kmemleak_free(const void *ptr) __ref; extern void kmemleak_free_part(const void *ptr, size_t size) __ref; extern void kmemleak_free_percpu(const void __percpu *ptr) __ref; +extern void kmemleak_update_trace(const void *ptr) __ref; extern void kmemleak_not_leak(const void *ptr) __ref; extern void kmemleak_ignore(const void *ptr) __ref; extern void kmemleak_scan_area(const void *ptr, size_t size, gfp_t gfp) __ref; @@ -83,6 +84,9 @@ static inline void kmemleak_free_recursive(const void *ptr, unsigned long flags) static inline void kmemleak_free_percpu(const void __percpu *ptr) { } +static inline void kmemleak_update_trace(const void *ptr) +{ +} static inline void kmemleak_not_leak(const void *ptr) { } diff --git a/mm/kmemleak.c b/mm/kmemleak.c index 3a36e2b16cba..61a64ed2fbef 100644 --- a/mm/kmemleak.c +++ b/mm/kmemleak.c @@ -990,6 +990,40 @@ void __ref kmemleak_free_percpu(const void __percpu *ptr) EXPORT_SYMBOL_GPL(kmemleak_free_percpu); /** + * kmemleak_update_trace - update object allocation stack trace + * @ptr: pointer to beginning of the object + * + * Override the object allocation stack trace for cases where the actual + * allocation place is not always useful. + */ +void __ref kmemleak_update_trace(const void *ptr) +{ + struct kmemleak_object *object; + unsigned long flags; + + pr_debug("%s(0x%p)\n", __func__, ptr); + + if (!kmemleak_enabled || IS_ERR_OR_NULL(ptr)) + return; + + object = find_and_get_object((unsigned long)ptr, 1); + if (!object) { +#ifdef DEBUG + kmemleak_warn("Updating stack trace for unknown object at %p\n", + ptr); +#endif + return; + } + + spin_lock_irqsave(&object->lock, flags); + object->trace_len = __save_stack_trace(object->trace); + spin_unlock_irqrestore(&object->lock, flags); + + put_object(object); +} +EXPORT_SYMBOL(kmemleak_update_trace); + +/** * kmemleak_not_leak - mark an allocated object as false positive * @ptr: pointer to beginning of the object *