From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751947AbcJIRPX (ORCPT ); Sun, 9 Oct 2016 13:15:23 -0400 Received: from mail-lf0-f42.google.com ([209.85.215.42]:35140 "EHLO mail-lf0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751547AbcJIRPW (ORCPT ); Sun, 9 Oct 2016 13:15:22 -0400 MIME-Version: 1.0 In-Reply-To: <1475904515-24970-6-git-send-email-joelaf@google.com> References: <1475904515-24970-1-git-send-email-joelaf@google.com> <1475904515-24970-6-git-send-email-joelaf@google.com> From: Joel Fernandes Date: Sun, 9 Oct 2016 10:15:19 -0700 Message-ID: Subject: Re: [PATCH 5/7] ramoops: Split ftrace buffer space into per-CPU zones To: linux-kernel@vger.kernel.org Cc: Steven Rostedt , Joel Fernandes , Anton Vorontsov , Colin Cross , Kees Cook , Tony Luck Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Oct 7, 2016 at 10:28 PM, Joel Fernandes wrote: > If FTRACE_PER_CPU flag is passed to ramoops pdata, split the space into > multiple zones depending on the number of CPUs. > > This speeds up the performance of function tracing by about 280% in my tests as > we avoid the locking. The trade off being lesser space available per CPU. Let > the ramoops user decide which option they want based on pdata flag. > > Signed-off-by: Joel Fernandes > --- > fs/pstore/ram.c | 70 +++++++++++++++++++++++++++++++++++----------- > include/linux/pstore_ram.h | 3 ++ > 2 files changed, 56 insertions(+), 17 deletions(-) > > diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c [..] > @@ -391,14 +418,21 @@ static void ramoops_free_przs(struct ramoops_context *cxt) > { > int i; > > - if (!cxt->przs) > - return; > + /* Free dump PRZs */ > + if (cxt->przs) { > + for (i = 0; i < cxt->max_dump_cnt; i++) > + persistent_ram_free(cxt->przs[i]); > > - for (i = 0; i < cxt->max_dump_cnt; i++) > - persistent_ram_free(cxt->przs[i]); > + kfree(cxt->przs); > + cxt->max_dump_cnt = 0; > + } > > - kfree(cxt->przs); > - cxt->max_dump_cnt = 0; > + /* Free ftrace PRZs */ > + if (cxt->fprzs) { > + for (i = 0; i < nr_cpu_ids; i++) > + persistent_ram_free(cxt->przs[i]); I am supposed to free fprzs[i] here, instead of przs[i]. Also need to check flag and free correct number of zones. Will fix for v2, sorry about that. Thanks, Joel