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=-6.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 DE9D0C83004 for ; Wed, 29 Apr 2020 11:31:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B1EE42074A for ; Wed, 29 Apr 2020 11:31:42 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=ellerman.id.au header.i=@ellerman.id.au header.b="ZTuGFBTe" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726785AbgD2Lbm (ORCPT ); Wed, 29 Apr 2020 07:31:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33354 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1726556AbgD2Lbl (ORCPT ); Wed, 29 Apr 2020 07:31:41 -0400 Received: from ozlabs.org (ozlabs.org [IPv6:2401:3900:2:1::2]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 929EEC03C1AD; Wed, 29 Apr 2020 04:31:41 -0700 (PDT) Received: from authenticated.ozlabs.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mail.ozlabs.org (Postfix) with ESMTPSA id 49BxDV0QRfz9sRY; Wed, 29 Apr 2020 21:31:38 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ellerman.id.au; s=201909; t=1588159898; bh=JUxQ1DDlvwJDXTYSg0PlVcfy+qm/d19EKj5KPqykW4A=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=ZTuGFBTe5ZDCRYmRf8ONj9kw4OOzYV0cVIHj998pCw1d1JqRzoZJWA0/c/y5gCTPk r+rzuwz8o6St+ED8g3XKqbQA4xaZRRDi4QqNt4PRDUJKACWR6chSzombKXzCoXMXG9 cNNlLtk3BoJYaKhgz5D8NG6Iwn2PgptzNZgNPNvIezf8TIbTfRsa2v7K8D/hRLMv1b jRlhdEsR529HAa8t01dU2Tj8b0ZVgvH9VEzW831JCo8HMi0I7p72w767xTZ15+735C Q/pND6PdteTKnPxv4mNt2lnQ7bSE71jwBvZ9ZQbD4lEZdtH+zFnUoVGLWSBCdP0cl5 H+Fr6RImwBrrw== From: Michael Ellerman To: Kajol Jain , acme@kernel.org, linuxppc-dev@lists.ozlabs.org, sukadev@linux.vnet.ibm.com Cc: linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, anju@linux.vnet.ibm.com, maddy@linux.vnet.ibm.com, ravi.bangoria@linux.ibm.com, peterz@infradead.org, yao.jin@linux.intel.com, ak@linux.intel.com, jolsa@kernel.org, kan.liang@linux.intel.com, jmario@redhat.com, alexander.shishkin@linux.intel.com, mingo@kernel.org, paulus@ozlabs.org, namhyung@kernel.org, mpetlan@redhat.com, gregkh@linuxfoundation.org, benh@kernel.crashing.org, mamatha4@linux.vnet.ibm.com, mark.rutland@arm.com, tglx@linutronix.de, kjain@linux.ibm.com Subject: Re: [PATCH v7 2/5] powerpc/hv-24x7: Add rtas call in hv-24x7 driver to get processor details In-Reply-To: <20200327063642.26175-3-kjain@linux.ibm.com> References: <20200327063642.26175-1-kjain@linux.ibm.com> <20200327063642.26175-3-kjain@linux.ibm.com> Date: Wed, 29 Apr 2020 21:31:54 +1000 Message-ID: <87ftcmfryt.fsf@mpe.ellerman.id.au> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Kajol, Some comments inline ... Kajol Jain writes: > For hv_24x7 socket/chip level events, specific chip-id to which > the data requested should be added as part of pmu events. > But number of chips/socket in the system details are not exposed. > > Patch implements read_sys_info_pseries() to get system > parameter values like number of sockets and chips per socket. > Rtas_call with token "PROCESSOR_MODULE_INFO" > is used to get these values. > > Sub-sequent patch exports these values via sysfs. > > Patch also make these parameters default to 1. > > Signed-off-by: Kajol Jain > --- > arch/powerpc/perf/hv-24x7.c | 72 ++++++++++++++++++++++++ > arch/powerpc/platforms/pseries/pseries.h | 3 + > 2 files changed, 75 insertions(+) > > diff --git a/arch/powerpc/perf/hv-24x7.c b/arch/powerpc/perf/hv-24x7.c > index 48e8f4b17b91..9ae00f29bd21 100644 > --- a/arch/powerpc/perf/hv-24x7.c > +++ b/arch/powerpc/perf/hv-24x7.c > @@ -20,6 +20,11 @@ > #include > #include > > +#ifdef CONFIG_PPC_RTAS This driver can only be build on pseries, and pseries always selects RTAS. So the ifdef is unncessary. > +#include > +#include <../../platforms/pseries/pseries.h> > +#endif That's not really what the platform header is intended for. You should put the extern in arch/powerpc/include/asm somewhere. Maybe rtas.h > @@ -57,6 +62,69 @@ static bool is_physical_domain(unsigned domain) > } > } > > +#ifdef CONFIG_PPC_RTAS Not needed. > +#define PROCESSOR_MODULE_INFO 43 Please document where these come from, presumably LoPAPR somewhere? > +#define PROCESSOR_MAX_LENGTH (8 * 1024) > + > +static int strbe16toh(const char *buf, int offset) > +{ > + return (buf[offset] << 8) + buf[offset + 1]; > +} I'm confused by this. "str" implies string, a string is an array of bytes and has no endian. But then be16 implies it's an array of __be16, in which case buf should be a __be16 *. > + > +static u32 physsockets; /* Physical sockets */ > +static u32 physchips; /* Physical chips */ No tabs there please. > + > +/* > + * Function read_sys_info_pseries() make a rtas_call which require > + * data buffer of size 8K. As standard 'rtas_data_buf' is of size > + * 4K, we are adding new local buffer 'rtas_local_data_buf'. > + */ > +char rtas_local_data_buf[PROCESSOR_MAX_LENGTH] __cacheline_aligned; static? > +/* > + * read_sys_info_pseries() > + * Retrieve the number of sockets and chips per socket details > + * through the get-system-parameter rtas call. > + */ > +void read_sys_info_pseries(void) > +{ > + int call_status, len, ntypes; > + > + /* > + * Making system parameter: chips and sockets default to 1. > + */ > + physsockets = 1; > + physchips = 1; > + memset(rtas_local_data_buf, 0, PROCESSOR_MAX_LENGTH); > + spin_lock(&rtas_data_buf_lock); You're not using the rtas_data_buf, so why are you taking the rtas_data_buf_lock? > + call_status = rtas_call(rtas_token("ibm,get-system-parameter"), 3, 1, > + NULL, > + PROCESSOR_MODULE_INFO, > + __pa(rtas_local_data_buf), > + PROCESSOR_MAX_LENGTH); > + > + spin_unlock(&rtas_data_buf_lock); > + > + if (call_status != 0) { > + pr_info("%s %s Error calling get-system-parameter (0x%x)\n", > + __FILE__, __func__, call_status); pr_err(), don't use __FILE__, this file already uses pr_fmt(). Not sure __func__ is really necessary either. return; Then you can deindent the next block. > + } else { > + rtas_local_data_buf[PROCESSOR_MAX_LENGTH - 1] = '\0'; > + len = strbe16toh(rtas_local_data_buf, 0); Why isn't the buffer a __be16 array, and then you just use be16_to_cpu() ? > + if (len < 6) > + return; > + > + ntypes = strbe16toh(rtas_local_data_buf, 2); > + > + if (!ntypes) > + return; What is ntypes? > + physsockets = strbe16toh(rtas_local_data_buf, 4); > + physchips = strbe16toh(rtas_local_data_buf, 6); > + } > +} > +#endif /* CONFIG_PPC_RTAS */ > + > /* Domains for which more than one result element are returned for each event. */ > static bool domain_needs_aggregation(unsigned int domain) > { > @@ -1605,6 +1673,10 @@ static int hv_24x7_init(void) > if (r) > return r; > > +#ifdef CONFIG_PPC_RTAS > + read_sys_info_pseries(); > +#endif > + > return 0; > } > > diff --git a/arch/powerpc/platforms/pseries/pseries.h b/arch/powerpc/platforms/pseries/pseries.h > index 13fa370a87e4..1727559ce304 100644 > --- a/arch/powerpc/platforms/pseries/pseries.h > +++ b/arch/powerpc/platforms/pseries/pseries.h > @@ -19,6 +19,9 @@ extern void request_event_sources_irqs(struct device_node *np, > struct pt_regs; > > extern int pSeries_system_reset_exception(struct pt_regs *regs); > +#ifdef CONFIG_PPC_RTAS > +extern void read_sys_info_pseries(void); > +#endif > extern int pSeries_machine_check_exception(struct pt_regs *regs); > extern long pseries_machine_check_realmode(struct pt_regs *regs); cheers