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-rw-r--r--arch/s390/kernel/perf_cpum_sf.c22
-rw-r--r--arch/s390/kernel/smp.c80
-rw-r--r--arch/s390/purgatory/Makefile6
-rw-r--r--arch/s390/purgatory/string.c3
4 files changed, 77 insertions, 34 deletions
diff --git a/arch/s390/kernel/perf_cpum_sf.c b/arch/s390/kernel/perf_cpum_sf.c
index de38fa5bbedf..20e07fdb3710 100644
--- a/arch/s390/kernel/perf_cpum_sf.c
+++ b/arch/s390/kernel/perf_cpum_sf.c
@@ -1261,18 +1261,28 @@ static void hw_perf_event_update(struct perf_event *event, int flush_all)
*/
if (flush_all && done)
break;
-
- /* If an event overflow happened, discard samples by
- * processing any remaining sample-data-blocks.
- */
- if (event_overflow)
- flush_all = 1;
}
/* Account sample overflows in the event hardware structure */
if (sampl_overflow)
OVERFLOW_REG(hwc) = DIV_ROUND_UP(OVERFLOW_REG(hwc) +
sampl_overflow, 1 + num_sdb);
+
+ /* Perf_event_overflow() and perf_event_account_interrupt() limit
+ * the interrupt rate to an upper limit. Roughly 1000 samples per
+ * task tick.
+ * Hitting this limit results in a large number
+ * of throttled REF_REPORT_THROTTLE entries and the samples
+ * are dropped.
+ * Slightly increase the interval to avoid hitting this limit.
+ */
+ if (event_overflow) {
+ SAMPL_RATE(hwc) += DIV_ROUND_UP(SAMPL_RATE(hwc), 10);
+ debug_sprintf_event(sfdbg, 1, "%s: rate adjustment %ld\n",
+ __func__,
+ DIV_ROUND_UP(SAMPL_RATE(hwc), 10));
+ }
+
if (sampl_overflow || event_overflow)
debug_sprintf_event(sfdbg, 4, "hw_perf_event_update: "
"overflow stats: sample=%llu event=%llu\n",
diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c
index fd742511985a..89fdf9b9e96f 100644
--- a/arch/s390/kernel/smp.c
+++ b/arch/s390/kernel/smp.c
@@ -731,39 +731,67 @@ static void __ref smp_get_core_info(struct sclp_core_info *info, int early)
static int smp_add_present_cpu(int cpu);
-static int __smp_rescan_cpus(struct sclp_core_info *info, int sysfs_add)
+static int smp_add_core(struct sclp_core_entry *core, cpumask_t *avail,
+ bool configured, bool early)
{
struct pcpu *pcpu;
- cpumask_t avail;
- int cpu, nr, i, j;
+ int cpu, nr, i;
u16 address;
nr = 0;
- cpumask_xor(&avail, cpu_possible_mask, cpu_present_mask);
- cpu = cpumask_first(&avail);
- for (i = 0; (i < info->combined) && (cpu < nr_cpu_ids); i++) {
- if (sclp.has_core_type && info->core[i].type != boot_core_type)
+ if (sclp.has_core_type && core->type != boot_core_type)
+ return nr;
+ cpu = cpumask_first(avail);
+ address = core->core_id << smp_cpu_mt_shift;
+ for (i = 0; (i <= smp_cpu_mtid) && (cpu < nr_cpu_ids); i++) {
+ if (pcpu_find_address(cpu_present_mask, address + i))
continue;
- address = info->core[i].core_id << smp_cpu_mt_shift;
- for (j = 0; j <= smp_cpu_mtid; j++) {
- if (pcpu_find_address(cpu_present_mask, address + j))
- continue;
- pcpu = pcpu_devices + cpu;
- pcpu->address = address + j;
- pcpu->state =
- (cpu >= info->configured*(smp_cpu_mtid + 1)) ?
- CPU_STATE_STANDBY : CPU_STATE_CONFIGURED;
- smp_cpu_set_polarization(cpu, POLARIZATION_UNKNOWN);
- set_cpu_present(cpu, true);
- if (sysfs_add && smp_add_present_cpu(cpu) != 0)
- set_cpu_present(cpu, false);
- else
- nr++;
- cpu = cpumask_next(cpu, &avail);
- if (cpu >= nr_cpu_ids)
+ pcpu = pcpu_devices + cpu;
+ pcpu->address = address + i;
+ if (configured)
+ pcpu->state = CPU_STATE_CONFIGURED;
+ else
+ pcpu->state = CPU_STATE_STANDBY;
+ smp_cpu_set_polarization(cpu, POLARIZATION_UNKNOWN);
+ set_cpu_present(cpu, true);
+ if (!early && smp_add_present_cpu(cpu) != 0)
+ set_cpu_present(cpu, false);
+ else
+ nr++;
+ cpumask_clear_cpu(cpu, avail);
+ cpu = cpumask_next(cpu, avail);
+ }
+ return nr;
+}
+
+static int __smp_rescan_cpus(struct sclp_core_info *info, bool early)
+{
+ struct sclp_core_entry *core;
+ cpumask_t avail;
+ bool configured;
+ u16 core_id;
+ int nr, i;
+
+ nr = 0;
+ cpumask_xor(&avail, cpu_possible_mask, cpu_present_mask);
+ /*
+ * Add IPL core first (which got logical CPU number 0) to make sure
+ * that all SMT threads get subsequent logical CPU numbers.
+ */
+ if (early) {
+ core_id = pcpu_devices[0].address >> smp_cpu_mt_shift;
+ for (i = 0; i < info->configured; i++) {
+ core = &info->core[i];
+ if (core->core_id == core_id) {
+ nr += smp_add_core(core, &avail, true, early);
break;
+ }
}
}
+ for (i = 0; i < info->combined; i++) {
+ configured = i < info->configured;
+ nr += smp_add_core(&info->core[i], &avail, configured, early);
+ }
return nr;
}
@@ -812,7 +840,7 @@ void __init smp_detect_cpus(void)
/* Add CPUs present at boot */
get_online_cpus();
- __smp_rescan_cpus(info, 0);
+ __smp_rescan_cpus(info, true);
put_online_cpus();
memblock_free_early((unsigned long)info, sizeof(*info));
}
@@ -1169,7 +1197,7 @@ int __ref smp_rescan_cpus(void)
smp_get_core_info(info, 0);
get_online_cpus();
mutex_lock(&smp_cpu_state_mutex);
- nr = __smp_rescan_cpus(info, 1);
+ nr = __smp_rescan_cpus(info, false);
mutex_unlock(&smp_cpu_state_mutex);
put_online_cpus();
kfree(info);
diff --git a/arch/s390/purgatory/Makefile b/arch/s390/purgatory/Makefile
index dc1ae4ff79d7..ff318acb3d77 100644
--- a/arch/s390/purgatory/Makefile
+++ b/arch/s390/purgatory/Makefile
@@ -13,8 +13,10 @@ $(obj)/sha256.o: $(srctree)/lib/sha256.c FORCE
$(obj)/mem.o: $(srctree)/arch/s390/lib/mem.S FORCE
$(call if_changed_rule,as_o_S)
-$(obj)/string.o: $(srctree)/arch/s390/lib/string.c FORCE
- $(call if_changed_rule,cc_o_c)
+KCOV_INSTRUMENT := n
+GCOV_PROFILE := n
+UBSAN_SANITIZE := n
+KASAN_SANITIZE := n
KBUILD_CFLAGS := -fno-strict-aliasing -Wall -Wstrict-prototypes
KBUILD_CFLAGS += -Wno-pointer-sign -Wno-sign-compare
diff --git a/arch/s390/purgatory/string.c b/arch/s390/purgatory/string.c
new file mode 100644
index 000000000000..c98c22a72db7
--- /dev/null
+++ b/arch/s390/purgatory/string.c
@@ -0,0 +1,3 @@
+// SPDX-License-Identifier: GPL-2.0
+#define __HAVE_ARCH_MEMCMP /* arch function */
+#include "../lib/string.c"