From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:59996 "EHLO mx0b-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726236AbhANOqX (ORCPT ); Thu, 14 Jan 2021 09:46:23 -0500 Date: Thu, 14 Jan 2021 14:57:38 +0100 From: Claudio Imbrenda Subject: Re: [kvm-unit-tests PATCH v4 2/9] s390x: Consolidate sclp read info Message-ID: <20210114145738.4de9f001@ibm-vm> In-Reply-To: <20210112132054.49756-3-frankja@linux.ibm.com> References: <20210112132054.49756-1-frankja@linux.ibm.com> <20210112132054.49756-3-frankja@linux.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit List-ID: To: Janosch Frank Cc: kvm@vger.kernel.org, thuth@redhat.com, david@redhat.com, borntraeger@de.ibm.com, cohuck@redhat.com, linux-s390@vger.kernel.org On Tue, 12 Jan 2021 08:20:47 -0500 Janosch Frank wrote: > Let's only read the information once and pass a pointer to it instead > of calling sclp multiple times. > > Signed-off-by: Janosch Frank > Reviewed-by: Cornelia Huck > Acked-by: Thomas Huth > --- > lib/s390x/io.c | 1 + > lib/s390x/sclp.c | 31 +++++++++++++++++++++++++------ > lib/s390x/sclp.h | 3 +++ > lib/s390x/smp.c | 27 +++++++++++---------------- > 4 files changed, 40 insertions(+), 22 deletions(-) > > diff --git a/lib/s390x/io.c b/lib/s390x/io.c > index 1ff0589..6a1da63 100644 > --- a/lib/s390x/io.c > +++ b/lib/s390x/io.c > @@ -34,6 +34,7 @@ void setup(void) > { > setup_args_progname(ipl_args); > setup_facilities(); > + sclp_read_info(); > sclp_console_setup(); > sclp_memory_setup(); > smp_setup(); > diff --git a/lib/s390x/sclp.c b/lib/s390x/sclp.c > index 08a4813..12916f5 100644 > --- a/lib/s390x/sclp.c > +++ b/lib/s390x/sclp.c > @@ -23,6 +23,8 @@ extern unsigned long stacktop; > static uint64_t storage_increment_size; > static uint64_t max_ram_size; > static uint64_t ram_size; > +char _read_info[PAGE_SIZE] __attribute__((__aligned__(PAGE_SIZE))); > +static ReadInfo *read_info; > > char _sccb[PAGE_SIZE] __attribute__((__aligned__(4096))); > static volatile bool sclp_busy; > @@ -108,6 +110,24 @@ static void sclp_read_scp_info(ReadInfo *ri, int > length) report_abort("READ_SCP_INFO failed"); > } > > +void sclp_read_info(void) > +{ > + sclp_read_scp_info((void *)_read_info, SCCB_SIZE); > + read_info = (ReadInfo *)_read_info; > +} > + > +int sclp_get_cpu_num(void) > +{ > + assert(read_info); > + return read_info->entries_cpu; > +} > + > +CPUEntry *sclp_get_cpu_entries(void) > +{ > + assert(read_info); > + return (CPUEntry *)(_read_info + read_info->offset_cpu); > +} > + > /* Perform service call. Return 0 on success, non-zero otherwise. */ > int sclp_service_call(unsigned int command, void *sccb) > { > @@ -125,23 +145,22 @@ int sclp_service_call(unsigned int command, > void *sccb) > void sclp_memory_setup(void) > { > - ReadInfo *ri = (void *)_sccb; > uint64_t rnmax, rnsize; > int cc; > > - sclp_read_scp_info(ri, SCCB_SIZE); > + assert(read_info); > > /* calculate the storage increment size */ > - rnsize = ri->rnsize; > + rnsize = read_info->rnsize; > if (!rnsize) { > - rnsize = ri->rnsize2; > + rnsize = read_info->rnsize2; > } > storage_increment_size = rnsize << 20; > > /* calculate the maximum memory size */ > - rnmax = ri->rnmax; > + rnmax = read_info->rnmax; > if (!rnmax) { > - rnmax = ri->rnmax2; > + rnmax = read_info->rnmax2; > } > max_ram_size = rnmax * storage_increment_size; > > diff --git a/lib/s390x/sclp.h b/lib/s390x/sclp.h > index 9a6aad0..acd86d5 100644 > --- a/lib/s390x/sclp.h > +++ b/lib/s390x/sclp.h > @@ -268,6 +268,9 @@ void sclp_wait_busy(void); > void sclp_mark_busy(void); > void sclp_console_setup(void); > void sclp_print(const char *str); > +void sclp_read_info(void); > +int sclp_get_cpu_num(void); > +CPUEntry *sclp_get_cpu_entries(void); > int sclp_service_call(unsigned int command, void *sccb); > void sclp_memory_setup(void); > uint64_t get_ram_size(void); > diff --git a/lib/s390x/smp.c b/lib/s390x/smp.c > index c4f02dc..dfcfd28 100644 > --- a/lib/s390x/smp.c > +++ b/lib/s390x/smp.c > @@ -23,7 +23,6 @@ > #include "smp.h" > #include "sclp.h" > > -static char cpu_info_buffer[PAGE_SIZE] > __attribute__((__aligned__(4096))); static struct cpu *cpus; > static struct cpu *cpu0; > static struct spinlock lock; > @@ -32,8 +31,7 @@ extern void smp_cpu_setup_state(void); > > int smp_query_num_cpus(void) > { > - struct ReadCpuInfo *info = (void *)cpu_info_buffer; > - return info->nr_configured; > + return sclp_get_cpu_num(); > } > > struct cpu *smp_cpu_from_addr(uint16_t addr) > @@ -226,10 +224,10 @@ void smp_teardown(void) > { > int i = 0; > uint16_t this_cpu = stap(); > - struct ReadCpuInfo *info = (void *)cpu_info_buffer; > + int num = smp_query_num_cpus(); > > spin_lock(&lock); > - for (; i < info->nr_configured; i++) { > + for (; i < num; i++) { > if (cpus[i].active && > cpus[i].addr != this_cpu) { > sigp_retry(cpus[i].addr, SIGP_STOP, 0, NULL); > @@ -243,22 +241,19 @@ extern uint64_t *stackptr; > void smp_setup(void) > { > int i = 0; > + int num = smp_query_num_cpus(); > unsigned short cpu0_addr = stap(); > - struct ReadCpuInfo *info = (void *)cpu_info_buffer; > + struct CPUEntry *entry = sclp_get_cpu_entries(); > > spin_lock(&lock); > - sclp_mark_busy(); > - info->h.length = PAGE_SIZE; > - sclp_service_call(SCLP_READ_CPU_INFO, cpu_info_buffer); > + if (num > 1) > + printf("SMP: Initializing, found %d cpus\n", num); > > - if (smp_query_num_cpus() > 1) > - printf("SMP: Initializing, found %d cpus\n", > info->nr_configured); - > - cpus = calloc(info->nr_configured, sizeof(cpus)); > - for (i = 0; i < info->nr_configured; i++) { > - cpus[i].addr = info->entries[i].address; > + cpus = calloc(num, sizeof(cpus)); > + for (i = 0; i < num; i++) { > + cpus[i].addr = entry[i].address; > cpus[i].active = false; > - if (info->entries[i].address == cpu0_addr) { > + if (entry[i].address == cpu0_addr) { > cpu0 = &cpus[i]; > cpu0->stack = stackptr; > cpu0->lowcore = (void *)0; Reviewed-by: Claudio Imbrenda