On 4/29/20 5:01 PM, Michael Ellerman wrote: > Hi Kajol, > > Some comments inline ... > > Kajol Jain <kj...@linux.ibm.com> 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 <kj...@linux.ibm.com> >> --- >> 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 <asm/io.h> >> #include <linux/byteorder/generic.h> >> >> +#ifdef CONFIG_PPC_RTAS > > This driver can only be build on pseries, and pseries always selects > RTAS. So the ifdef is unncessary. Hi Michael, Thanks for review, I will remove this check. > >> +#include <asm/rtas.h> >> +#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? > Sure, will add the details. >> +#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 *. > Yes right, actually I was following implementation in util-linux. But what you suggested make more sense, will update accordingly. >> + >> +static u32 physsockets; /* Physical sockets */ >> +static u32 physchips; /* Physical chips */ > > No tabs there please. Sure will update. > >> + >> +/* >> + * 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? Sure, I will add new lock specific for rtas_local_data_buf > >> + 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 ntype ntype specify processor module type > >> + 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 > Will remove this config checks. Thanks, Kajol Jain >> + >> 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 >