From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4F0E6C6778C for ; Tue, 3 Jul 2018 13:40:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 05D3822464 for ; Tue, 3 Jul 2018 13:40:36 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 05D3822464 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753488AbeGCNkc (ORCPT ); Tue, 3 Jul 2018 09:40:32 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:35600 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752508AbeGCNka (ORCPT ); Tue, 3 Jul 2018 09:40:30 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 5016240122BF; Tue, 3 Jul 2018 13:40:30 +0000 (UTC) Received: from krava (unknown [10.43.17.196]) by smtp.corp.redhat.com (Postfix) with SMTP id 945F52026D76; Tue, 3 Jul 2018 13:40:27 +0000 (UTC) Date: Tue, 3 Jul 2018 15:40:26 +0200 From: Jiri Olsa To: Mathieu Poirier Cc: peterz@infradead.org, acme@kernel.org, mingo@redhat.com, tglx@linutronix.de, alexander.shishkin@linux.intel.com, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, will.deacon@arm.com, mark.rutland@arm.com, namhyung@kernel.org, adrian.hunter@intel.com, ast@kernel.org, gregkh@linuxfoundation.org, hpa@zytor.com, linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH 5/6] perf/core: Use ioctl to communicate driver configuration to kernel Message-ID: <20180703134026.GA3728@krava> References: <1530570810-28929-1-git-send-email-mathieu.poirier@linaro.org> <1530570810-28929-6-git-send-email-mathieu.poirier@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1530570810-28929-6-git-send-email-mathieu.poirier@linaro.org> User-Agent: Mutt/1.10.0 (2018-05-17) X-Scanned-By: MIMEDefang 2.78 on 10.11.54.4 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.5]); Tue, 03 Jul 2018 13:40:30 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.5]); Tue, 03 Jul 2018 13:40:30 +0000 (UTC) for IP:'10.11.54.4' DOMAIN:'int-mx04.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'jolsa@redhat.com' RCPT:'' Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jul 02, 2018 at 04:33:29PM -0600, Mathieu Poirier wrote: SNIP > +static int > +perf_event_process_drv_config(struct perf_event *event, char *config_str) > +{ > + int ret = -EINVAL; > + void *drv_data; > + > + /* Make sure ctx.mutex it held */ > + lockdep_assert_held(&event->ctx->mutex); > + > + /* Children take their configuration from their parent */ > + if (WARN_ON_ONCE(event->parent)) > + goto out; > + > + drv_data = event->pmu->drv_config_validate(event, config_str); > + if (!drv_data) > + goto out; what's this check for? doc does not mention that, also the coresight callback does not return NULL jirka