From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932816AbZKZEfo (ORCPT ); Wed, 25 Nov 2009 23:35:44 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932186AbZKZEfm (ORCPT ); Wed, 25 Nov 2009 23:35:42 -0500 Received: from mail-ew0-f219.google.com ([209.85.219.219]:61251 "EHLO mail-ew0-f219.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932685AbZKZEfk (ORCPT ); Wed, 25 Nov 2009 23:35:40 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=from:to:cc:subject:date:message-id:x-mailer:in-reply-to:references; b=LQdc6xQlhbLp4CBIbrOEnFRcAsuUT0VD7JAJtOBLCRNhaVYjtqXGDSMg4sB+wRGbRb fo8w9A2eElat1O4RjzDqVc7zSI1yJPWYAIhFVqxkSE+ZJyrAtae9Ld5FTdIV3PAOKjw7 +WaksD9m1jnwlg/LiwZtBB9hNnCBdtXPGVmLI= From: Frederic Weisbecker To: Ingo Molnar Cc: LKML , Frederic Weisbecker , Peter Zijlstra , Arnaldo Carvalho de Melo , Paul Mackerras , Prasad Subject: [PATCH 2/3] hw-breakpoints: Improve in-kernel event creation error granularity Date: Thu, 26 Nov 2009 05:35:41 +0100 Message-Id: <1259210142-5714-2-git-send-regression-fweisbec@gmail.com> X-Mailer: git-send-email 1.6.2.3 In-Reply-To: <1259210142-5714-1-git-send-regression-fweisbec@gmail.com> References: <1259210142-5714-1-git-send-regression-fweisbec@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In fail case, perf_event_create_kernel_counter() returns NULL instead of an error, which doesn't help us to inform the user about the origin of the problem from the outer most callers. Often we can just return -EINVAL, which doesn't help anyone when it's eventually about a memory allocation failure. Then, this patch makes perf_event_create_kernel_counter() always returning a detailed error code. Signed-off-by: Frederic Weisbecker Cc: Peter Zijlstra Cc: Arnaldo Carvalho de Melo Cc: Paul Mackerras Cc: Prasad --- kernel/perf_event.c | 20 +++++++++++--------- 1 files changed, 11 insertions(+), 9 deletions(-) diff --git a/kernel/perf_event.c b/kernel/perf_event.c index 35df94e..34a1b9d 100644 --- a/kernel/perf_event.c +++ b/kernel/perf_event.c @@ -4780,14 +4780,17 @@ perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu, */ ctx = find_get_context(pid, cpu); - if (IS_ERR(ctx)) - return NULL; + if (IS_ERR(ctx)) { + err = PTR_ERR(ctx); + goto err_exit; + } event = perf_event_alloc(attr, cpu, ctx, NULL, NULL, callback, GFP_KERNEL); - err = PTR_ERR(event); - if (IS_ERR(event)) + if (IS_ERR(event)) { + err = PTR_ERR(event); goto err_put_context; + } event->filp = NULL; WARN_ON_ONCE(ctx->parent_ctx); @@ -4804,11 +4807,10 @@ perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu, return event; -err_put_context: - if (err < 0) - put_ctx(ctx); - - return NULL; + err_put_context: + put_ctx(ctx); + err_exit: + return ERR_PTR(err); } EXPORT_SYMBOL_GPL(perf_event_create_kernel_counter); -- 1.6.2.3