The patch titled
alpha-implement-hw-performance-events-on-the-ev67-and-later-cpus-v2
has been added to the -mm tree. Its filename is
alpha-implement-hw-performance-events-on-the-ev67-and-later-cpus-v2.patch
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out what to do about this
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------------------------------------------------------
Subject: alpha-implement-hw-performance-events-on-the-ev67-and-later-cpus-v2
From: Michael Cree <mcree@xxxxxxxxxxxx>
Signed-off-by: Michael Cree <mcree@xxxxxxxxxxxx>
Cc: Richard Henderson <rth@xxxxxxxxxxx>
Cc: Ivan Kokshaysky <ink@xxxxxxxxxxxxxxxxxxxx>
Cc: Matt Turner <mattst88@xxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxx>
Cc: Jay Estabrook <jay.estabrook@xxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
arch/alpha/kernel/perf_event.c | 32 ++++++++++++++++++-------------
arch/alpha/kernel/time.c | 26 +++++++++++++++++++++++++
2 files changed, 45 insertions(+), 13 deletions(-)
diff -puN arch/alpha/kernel/perf_event.c~alpha-implement-hw-performance-events-on-the-ev67-and-later-cpus-v2 arch/alpha/kernel/perf_event.c
--- a/arch/alpha/kernel/perf_event.c~alpha-implement-hw-performance-events-on-the-ev67-and-later-cpus-v2
+++ a/arch/alpha/kernel/perf_event.c
@@ -517,8 +517,10 @@ static void alpha_pmu_read(struct perf_e
static void alpha_pmu_unthrottle(struct perf_event *event)
{
struct hw_perf_event *hwc = &event->hw;
+ struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
- wrperfmon(PERFMON_CMD_ENABLE, (1<<hwc->idx));
+ cpuc->idx_mask |= 1UL<<hwc->idx;
+ wrperfmon(PERFMON_CMD_ENABLE, (1UL<<hwc->idx));
}
@@ -756,12 +758,19 @@ static void alpha_perf_event_irq_handler
__get_cpu_var(irq_pmi_count)++;
cpuc = &__get_cpu_var(cpu_hw_events);
- /* la_ptr is the counter that overflowed. */
+ /* Completely counting through the PMC's period to trigger a new PMC
+ * overflow interrupt while in this interrupt routine is utterly
+ * disastrous! The EV6 and EV67 counters are sufficiently large to
+ * prevent this but to be really sure disable the PMCs.
+ */
+ wrperfmon(PERFMON_CMD_DISABLE, cpuc->idx_mask);
- if (la_ptr >= perf_max_events) {
+ /* la_ptr is the counter that overflowed. */
+ if (unlikely(la_ptr >= perf_max_events)) {
/* This should never occur! */
irq_err_count++;
pr_warning("PMI: silly index %ld\n", la_ptr);
+ wrperfmon(PERFMON_CMD_ENABLE, cpuc->idx_mask);
return;
}
@@ -773,17 +782,19 @@ static void alpha_perf_event_irq_handler
break;
}
- if (j == cpuc->n_events) {
+ if (unlikely(j == cpuc->n_events)) {
/* This can occur if the event is disabled right on a PMC overflow. */
+ wrperfmon(PERFMON_CMD_ENABLE, cpuc->idx_mask);
return;
}
event = cpuc->event[j];
- if (!event) {
+ if (unlikely(!event)) {
/* This should never occur! */
irq_err_count++;
pr_warning("PMI: No event at index %d!\n", idx);
+ wrperfmon(PERFMON_CMD_ENABLE, cpuc->idx_mask);
return;
}
@@ -792,24 +803,19 @@ static void alpha_perf_event_irq_handler
data.period = event->hw.last_period;
if (alpha_perf_event_set_period(event, hwc, idx)) {
- if (perf_event_overflow(event, 0, &data, regs)) {
+ if (perf_event_overflow(event, 1, &data, regs)) {
/* Interrupts coming too quickly; "throttle" the
* counter, i.e., disable it for a little while.
*/
- wrperfmon(PERFMON_CMD_DISABLE, 1<<idx);
+ cpuc->idx_mask &= ~(1UL<<idx);
}
}
+ wrperfmon(PERFMON_CMD_ENABLE, cpuc->idx_mask);
return;
}
-/* I wonder what this is for ??? */
-void set_perf_event_pending(void)
-{
-}
-
-
/*
* Init call to initialise performance events at kernel startup.
diff -puN arch/alpha/kernel/time.c~alpha-implement-hw-performance-events-on-the-ev67-and-later-cpus-v2 arch/alpha/kernel/time.c
--- a/arch/alpha/kernel/time.c~alpha-implement-hw-performance-events-on-the-ev67-and-later-cpus-v2
+++ a/arch/alpha/kernel/time.c
@@ -41,6 +41,7 @@
#include <linux/init.h>
#include <linux/bcd.h>
#include <linux/profile.h>
+#include <linux/perf_event.h>
#include <asm/uaccess.h>
#include <asm/io.h>
@@ -82,6 +83,26 @@ static struct {
unsigned long est_cycle_freq;
+#ifdef CONFIG_PERF_EVENTS
+
+DEFINE_PER_CPU(u8, perf_event_pending);
+
+#define set_perf_event_pending_flag() __get_cpu_var(perf_event_pending) = 1
+#define test_perf_event_pending() __get_cpu_var(perf_event_pending)
+#define clear_perf_event_pending() __get_cpu_var(perf_event_pending) = 0
+
+void set_perf_event_pending(void)
+{
+ set_perf_event_pending_flag();
+}
+
+#else /* CONFIG_PERF_EVENTS */
+
+#define test_perf_event_pending() 0
+#define clear_perf_event_pending()
+
+#endif /* CONFIG_PERF_EVENTS */
+
static inline __u32 rpcc(void)
{
@@ -175,6 +196,11 @@ irqreturn_t timer_interrupt(int irq, voi
update_process_times(user_mode(get_irq_regs()));
#endif
+ if (test_perf_event_pending()) {
+ clear_perf_event_pending();
+ perf_event_do_pending();
+ }
+
return IRQ_HANDLED;
}
_
Patches currently in -mm which might be from mcree@xxxxxxxxxxxx are
alpha-add-performance-monitor-interrupt-counter.patch
alpha-add-wrperfmonh-header-file-to-aid-use-of-wrperfmon-palcall.patch
alpha-implement-hw-performance-events-on-the-ev67-and-later-cpus.patch
alpha-implement-hw-performance-events-on-the-ev67-and-later-cpus-v2.patch
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