From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754481Ab1FGXlp (ORCPT ); Tue, 7 Jun 2011 19:41:45 -0400 Received: from smtp-out.google.com ([216.239.44.51]:58666 "EHLO smtp-out.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753700Ab1FGXlo (ORCPT ); Tue, 7 Jun 2011 19:41:44 -0400 DomainKey-Signature: a=rsa-sha1; s=beta; d=google.com; c=nofws; q=dns; h=from:to:cc:subject:date:message-id:x-mailer:in-reply-to:references; b=jZcTF2nDjefkPOco9vepOnsFFm+mqaeflAYN7B18aH7u0cVHyMrpfCwZJCITCo1g3 fTgD6yx5nLTiUAb5HBBkg== From: Vaibhav Nagarnaik To: Steven Rostedt , Ingo Molnar , Frederic Weisbecker Cc: Michael Rubin , David Sharp , linux-kernel@vger.kernel.org, Vaibhav Nagarnaik Subject: [PATCH] trace: Set __GFP_NORETRY flag for ring buffer allocating process Date: Tue, 7 Jun 2011 16:41:28 -0700 Message-Id: <1307490088-8612-1-git-send-email-vnagarnaik@google.com> X-Mailer: git-send-email 1.7.3.1 In-Reply-To: <1306519125-19301-1-git-send-email-vnagarnaik@google.com> References: <1306519125-19301-1-git-send-email-vnagarnaik@google.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The tracing ring buffer is allocated from kernel memory. While allocating a large chunk of memory, OOM might happen which destabilizes the system. Thus random processes might get killed during the allocation. This patch adds __GFP_NORETRY flag to the ring buffer allocation calls to make it fail more gracefully if the system will not be able to complete the allocation request. Signed-off-by: Vaibhav Nagarnaik --- kernel/trace/ring_buffer.c | 15 ++++++++++----- 1 files changed, 10 insertions(+), 5 deletions(-) diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index 2780e60..ec817d5 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -1005,7 +1005,8 @@ static int rb_allocate_pages(struct ring_buffer_per_cpu *cpu_buffer, for (i = 0; i < nr_pages; i++) { struct page *page; bpage = kzalloc_node(ALIGN(sizeof(*bpage), cache_line_size()), - GFP_KERNEL, cpu_to_node(cpu_buffer->cpu)); + GFP_KERNEL | __GFP_NORETRY, + cpu_to_node(cpu_buffer->cpu)); if (!bpage) goto free_pages; @@ -1014,7 +1015,7 @@ static int rb_allocate_pages(struct ring_buffer_per_cpu *cpu_buffer, list_add(&bpage->list, &pages); page = alloc_pages_node(cpu_to_node(cpu_buffer->cpu), - GFP_KERNEL, 0); + GFP_KERNEL | __GFP_NORETRY, 0); if (!page) goto free_pages; bpage->page = page_address(page); @@ -1378,11 +1379,13 @@ int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size) struct page *page; bpage = kzalloc_node(ALIGN(sizeof(*bpage), cache_line_size()), - GFP_KERNEL, cpu_to_node(cpu)); + GFP_KERNEL | __GFP_NORETRY, + cpu_to_node(cpu)); if (!bpage) goto free_pages; list_add(&bpage->list, &pages); - page = alloc_pages_node(cpu_to_node(cpu), GFP_KERNEL, + page = alloc_pages_node(cpu_to_node(cpu), + GFP_KERNEL | __GFP_NORETRY, 0); if (!page) goto free_pages; @@ -3737,7 +3740,9 @@ void *ring_buffer_alloc_read_page(struct ring_buffer *buffer, int cpu) struct buffer_data_page *bpage; struct page *page; - page = alloc_pages_node(cpu_to_node(cpu), GFP_KERNEL, 0); + page = alloc_pages_node(cpu_to_node(cpu), + GFP_KERNEL | __GFP_NORETRY, + 0); if (!page) return NULL; -- 1.7.3.1