From mboxrd@z Thu Jan 1 00:00:00 1970 From: Madhavan Srinivasan Subject: Re: [PATCH v7 2/5] powerpc/hv-24x7: Add rtas call in hv-24x7 driver to get processor details Date: Wed, 29 Apr 2020 13:32:04 +0530 Message-ID: References: <20200327063642.26175-1-kjain@linux.ibm.com> <20200327063642.26175-3-kjain@linux.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20200327063642.26175-3-kjain@linux.ibm.com> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Kajol Jain , acme@kernel.org, linuxppc-dev@lists.ozlabs.org, mpe@ellerman.id.au, 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 List-Id: linux-perf-users.vger.kernel.org On 3/27/20 12:06 PM, Kajol Jain wrote: > 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. Patch looks good to me. Reviewed-by: Madhavan Srinivasan > 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 > +#include > +#include <../../platforms/pseries/pseries.h> > +#endif > + > #include "hv-24x7.h" > #include "hv-24x7-catalog.h" > #include "hv-common.h" > @@ -57,6 +62,69 @@ static bool is_physical_domain(unsigned domain) > } > } > > +#ifdef CONFIG_PPC_RTAS > +#define PROCESSOR_MODULE_INFO 43 > +#define PROCESSOR_MAX_LENGTH (8 * 1024) > + > +static int strbe16toh(const char *buf, int offset) > +{ > + return (buf[offset] << 8) + buf[offset + 1]; > +} > + > +static u32 physsockets; /* Physical sockets */ > +static u32 physchips; /* Physical chips */ > + > +/* > + * 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; > + > +/* > + * 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); > + > + 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); > + } else { > + rtas_local_data_buf[PROCESSOR_MAX_LENGTH - 1] = '\0'; > + len = strbe16toh(rtas_local_data_buf, 0); > + if (len < 6) > + return; > + > + ntypes = strbe16toh(rtas_local_data_buf, 2); > + > + if (!ntypes) > + return; > + 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); >