Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932454Ab3CLPgm (ORCPT ); Tue, 12 Mar 2013 11:36:42 -0400 Received: from mx1.redhat.com ([209.132.183.28]:1447 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932111Ab3CLPgl (ORCPT ); Tue, 12 Mar 2013 11:36:41 -0400 Date: Tue, 12 Mar 2013 16:36:09 +0100 From: Jiri Olsa To: Peter Zijlstra Cc: linux-kernel@vger.kernel.org, Corey Ashford , Frederic Weisbecker , Ingo Molnar , Namhyung Kim , Paul Mackerras , Arnaldo Carvalho de Melo Subject: Re: [PATCHv3] perf: Fix vmalloc ring buffer free function Message-ID: <20130312153609.GC32001@krava.brq.redhat.com> References: <1362994843.10972.40.camel@laptop> <20130311112105.GA9737@krava.brq.redhat.com> <1363019193.14933.14.camel@laptop> <20130311164309.GG13679@krava.brq.redhat.com> <1363023885.14933.16.camel@laptop> <20130311180229.GI13679@krava.brq.redhat.com> <20130312100502.GC1348@krava.brq.redhat.com> <1363084030.14933.23.camel@laptop> <20130312135219.GA32001@krava.brq.redhat.com> <1363101972.24558.3.camel@laptop> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1363101972.24558.3.camel@laptop> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1085 Lines: 31 On Tue, Mar 12, 2013 at 04:26:12PM +0100, Peter Zijlstra wrote: > On Tue, 2013-03-12 at 14:52 +0100, Jiri Olsa wrote: > > > @@ -373,7 +373,7 @@ struct ring_buffer *rb_alloc(int nr_pages, long watermark, int cpu, int flags) > > > rb->user_page = all_buf; > > > rb->data_pages[0] = all_buf + PAGE_SIZE; > > > rb->page_order = ilog2(nr_pages); > > > - rb->nr_pages = 1; > > > + rb->nr_pages = nr_pages; > > > > > > > hum, and this ^^^ breaks perf_data_size(rb) ;) > > > > static inline unsigned long perf_data_size(struct ring_buffer *rb) > > { > > return rb->nr_pages << (PAGE_SHIFT + page_order(rb)); > > } > > How so? 0 << n keeps being 0, right? > you do 'rb->nr_pages = nr_pages' which was 1 before.. that will bump up the return value should do '1 << x' but doing 'nr_pages << x' instead jirka -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/