Blackfin: initial perf_event support
authorMike Frysinger <vapier@gentoo.org>
Fri, 6 May 2011 15:47:52 +0000 (11:47 -0400)
committerMike Frysinger <vapier@gentoo.org>
Wed, 25 May 2011 12:24:09 +0000 (08:24 -0400)
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
arch/blackfin/Kconfig
arch/blackfin/include/asm/bfin_pfmon.h [new file with mode: 0644]
arch/blackfin/include/asm/perf_event.h [new file with mode: 0644]
arch/blackfin/kernel/Makefile
arch/blackfin/kernel/perf_event.c [new file with mode: 0644]

index 8addb12..a18180f 100644 (file)
@@ -24,11 +24,13 @@ config BLACKFIN
        select HAVE_FUNCTION_TRACER
        select HAVE_FUNCTION_TRACE_MCOUNT_TEST
        select HAVE_IDE
+       select HAVE_IRQ_WORK
        select HAVE_KERNEL_GZIP if RAMKERNEL
        select HAVE_KERNEL_BZIP2 if RAMKERNEL
        select HAVE_KERNEL_LZMA if RAMKERNEL
        select HAVE_KERNEL_LZO if RAMKERNEL
        select HAVE_OPROFILE
+       select HAVE_PERF_EVENTS
        select ARCH_WANT_OPTIONAL_GPIOLIB
        select HAVE_GENERIC_HARDIRQS
        select GENERIC_ATOMIC64
diff --git a/arch/blackfin/include/asm/bfin_pfmon.h b/arch/blackfin/include/asm/bfin_pfmon.h
new file mode 100644 (file)
index 0000000..accd47e
--- /dev/null
@@ -0,0 +1,44 @@
+/*
+ * Blackfin Performance Monitor definitions
+ *
+ * Copyright 2005-2011 Analog Devices Inc.
+ *
+ * Licensed under the ADI BSD license or GPL-2 (or later).
+ */
+
+#ifndef __ASM_BFIN_PFMON_H__
+#define __ASM_BFIN_PFMON_H__
+
+/* PFCTL Masks */
+#define PFMON_MASK     0xff
+#define PFCEN_MASK     0x3
+#define PFCEN_DISABLE  0x0
+#define PFCEN_ENABLE_USER      0x1
+#define PFCEN_ENABLE_SUPV      0x2
+#define PFCEN_ENABLE_ALL       (PFCEN_ENABLE_USER | PFCEN_ENABLE_SUPV)
+
+#define PFPWR_P        0
+#define PEMUSW0_P      2
+#define PFCEN0_P       3
+#define PFMON0_P       5
+#define PEMUSW1_P      13
+#define PFCEN1_P       14
+#define PFMON1_P       16
+#define PFCNT0_P       24
+#define PFCNT1_P       25
+
+#define PFPWR  (1 << PFPWR_P)
+#define PEMUSW(n, x)   ((x) << ((n) ? PEMUSW1_P : PEMUSW0_P))
+#define PEMUSW0        PEMUSW(0, 1)
+#define PEMUSW1        PEMUSW(1, 1)
+#define PFCEN(n, x)    ((x) << ((n) ? PFCEN1_P : PFCEN0_P))
+#define PFCEN0 PFCEN(0, PFCEN_MASK)
+#define PFCEN1 PFCEN(1, PFCEN_MASK)
+#define PFCNT(n, x)    ((x) << ((n) ? PFCNT1_P : PFCNT0_P))
+#define PFCNT0 PFCNT(0, 1)
+#define PFCNT1 PFCNT(1, 1)
+#define PFMON(n, x)    ((x) << ((n) ? PFMON1_P : PFMON0_P))
+#define PFMON0 PFMON(0, PFMON_MASK)
+#define PFMON1 PFMON(1, PFMON_MASK)
+
+#endif
diff --git a/arch/blackfin/include/asm/perf_event.h b/arch/blackfin/include/asm/perf_event.h
new file mode 100644 (file)
index 0000000..3d2b171
--- /dev/null
@@ -0,0 +1 @@
+#define MAX_HWEVENTS 2
index 18ba6ab..d550b24 100644 (file)
@@ -33,6 +33,7 @@ obj-$(CONFIG_EARLY_PRINTK)           += shadow_console.o
 obj-$(CONFIG_STACKTRACE)             += stacktrace.o
 obj-$(CONFIG_DEBUG_VERBOSE)          += trace.o
 obj-$(CONFIG_BFIN_PSEUDODBG_INSNS)   += pseudodbg.o
+obj-$(CONFIG_PERF_EVENTS)            += perf_event.o
 
 # the kgdb test puts code into L2 and without linker
 # relaxation, we need to force long calls to/from it
diff --git a/arch/blackfin/kernel/perf_event.c b/arch/blackfin/kernel/perf_event.c
new file mode 100644 (file)
index 0000000..04300f2
--- /dev/null
@@ -0,0 +1,498 @@
+/*
+ * Blackfin performance counters
+ *
+ * Copyright 2011 Analog Devices Inc.
+ *
+ * Ripped from SuperH version:
+ *
+ *  Copyright (C) 2009  Paul Mundt
+ *
+ * Heavily based on the x86 and PowerPC implementations.
+ *
+ * x86:
+ *  Copyright (C) 2008 Thomas Gleixner <tglx@linutronix.de>
+ *  Copyright (C) 2008-2009 Red Hat, Inc., Ingo Molnar
+ *  Copyright (C) 2009 Jaswinder Singh Rajput
+ *  Copyright (C) 2009 Advanced Micro Devices, Inc., Robert Richter
+ *  Copyright (C) 2008-2009 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com>
+ *  Copyright (C) 2009 Intel Corporation, <markus.t.metzger@intel.com>
+ *
+ * ppc:
+ *  Copyright 2008-2009 Paul Mackerras, IBM Corporation.
+ *
+ * Licensed under the GPL-2 or later.
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/perf_event.h>
+#include <asm/bfin_pfmon.h>
+
+/*
+ * We have two counters, and each counter can support an event type.
+ * The 'o' is PFCNTx=1 and 's' is PFCNTx=0
+ *
+ * 0x04 o pc invariant branches
+ * 0x06 o mispredicted branches
+ * 0x09 o predicted branches taken
+ * 0x0B o EXCPT insn
+ * 0x0C o CSYNC/SSYNC insn
+ * 0x0D o Insns committed
+ * 0x0E o Interrupts taken
+ * 0x0F o Misaligned address exceptions
+ * 0x80 o Code memory fetches stalled due to DMA
+ * 0x83 o 64bit insn fetches delivered
+ * 0x9A o data cache fills (bank a)
+ * 0x9B o data cache fills (bank b)
+ * 0x9C o data cache lines evicted (bank a)
+ * 0x9D o data cache lines evicted (bank b)
+ * 0x9E o data cache high priority fills
+ * 0x9F o data cache low priority fills
+ * 0x00 s loop 0 iterations
+ * 0x01 s loop 1 iterations
+ * 0x0A s CSYNC/SSYNC stalls
+ * 0x10 s DAG read/after write hazards
+ * 0x13 s RAW data hazards
+ * 0x81 s code TAG stalls
+ * 0x82 s code fill stalls
+ * 0x90 s processor to memory stalls
+ * 0x91 s data memory stalls not hidden by 0x90
+ * 0x92 s data store buffer full stalls
+ * 0x93 s data memory write buffer full stalls due to high->low priority
+ * 0x95 s data memory fill buffer stalls
+ * 0x96 s data TAG collision stalls
+ * 0x97 s data collision stalls
+ * 0x98 s data stalls
+ * 0x99 s data stalls sent to processor
+ */
+
+static const int event_map[] = {
+       /* use CYCLES cpu register */
+       [PERF_COUNT_HW_CPU_CYCLES]          = -1,
+       [PERF_COUNT_HW_INSTRUCTIONS]        = 0x0D,
+       [PERF_COUNT_HW_CACHE_REFERENCES]    = -1,
+       [PERF_COUNT_HW_CACHE_MISSES]        = 0x83,
+       [PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = 0x09,
+       [PERF_COUNT_HW_BRANCH_MISSES]       = 0x06,
+       [PERF_COUNT_HW_BUS_CYCLES]          = -1,
+};
+
+#define C(x)   PERF_COUNT_HW_CACHE_##x
+
+static const int cache_events[PERF_COUNT_HW_CACHE_MAX]
+                             [PERF_COUNT_HW_CACHE_OP_MAX]
+                             [PERF_COUNT_HW_CACHE_RESULT_MAX] =
+{
+       [C(L1D)] = {    /* Data bank A */
+               [C(OP_READ)] = {
+                       [C(RESULT_ACCESS)] = 0,
+                       [C(RESULT_MISS)  ] = 0x9A,
+               },
+               [C(OP_WRITE)] = {
+                       [C(RESULT_ACCESS)] = 0,
+                       [C(RESULT_MISS)  ] = 0,
+               },
+               [C(OP_PREFETCH)] = {
+                       [C(RESULT_ACCESS)] = 0,
+                       [C(RESULT_MISS)  ] = 0,
+               },
+       },
+
+       [C(L1I)] = {
+               [C(OP_READ)] = {
+                       [C(RESULT_ACCESS)] = 0,
+                       [C(RESULT_MISS)  ] = 0x83,
+               },
+               [C(OP_WRITE)] = {
+                       [C(RESULT_ACCESS)] = -1,
+                       [C(RESULT_MISS)  ] = -1,
+               },
+               [C(OP_PREFETCH)] = {
+                       [C(RESULT_ACCESS)] = 0,
+                       [C(RESULT_MISS)  ] = 0,
+               },
+       },
+
+       [C(LL)] = {
+               [C(OP_READ)] = {
+                       [C(RESULT_ACCESS)] = -1,
+                       [C(RESULT_MISS)  ] = -1,
+               },
+               [C(OP_WRITE)] = {
+                       [C(RESULT_ACCESS)] = -1,
+                       [C(RESULT_MISS)  ] = -1,
+               },
+               [C(OP_PREFETCH)] = {
+                       [C(RESULT_ACCESS)] = -1,
+                       [C(RESULT_MISS)  ] = -1,
+               },
+       },
+
+       [C(DTLB)] = {
+               [C(OP_READ)] = {
+                       [C(RESULT_ACCESS)] = -1,
+                       [C(RESULT_MISS)  ] = -1,
+               },
+               [C(OP_WRITE)] = {
+                       [C(RESULT_ACCESS)] = -1,
+                       [C(RESULT_MISS)  ] = -1,
+               },
+               [C(OP_PREFETCH)] = {
+                       [C(RESULT_ACCESS)] = -1,
+                       [C(RESULT_MISS)  ] = -1,
+               },
+       },
+
+       [C(ITLB)] = {
+               [C(OP_READ)] = {
+                       [C(RESULT_ACCESS)] = -1,
+                       [C(RESULT_MISS)  ] = -1,
+               },
+               [C(OP_WRITE)] = {
+                       [C(RESULT_ACCESS)] = -1,
+                       [C(RESULT_MISS)  ] = -1,
+               },
+               [C(OP_PREFETCH)] = {
+                       [C(RESULT_ACCESS)] = -1,
+                       [C(RESULT_MISS)  ] = -1,
+               },
+       },
+
+       [C(BPU)] = {
+               [C(OP_READ)] = {
+                       [C(RESULT_ACCESS)] = -1,
+                       [C(RESULT_MISS)  ] = -1,
+               },
+               [C(OP_WRITE)] = {
+                       [C(RESULT_ACCESS)] = -1,
+                       [C(RESULT_MISS)  ] = -1,
+               },
+               [C(OP_PREFETCH)] = {
+                       [C(RESULT_ACCESS)] = -1,
+                       [C(RESULT_MISS)  ] = -1,
+               },
+       },
+};
+
+const char *perf_pmu_name(void)
+{
+       return "bfin";
+}
+EXPORT_SYMBOL(perf_pmu_name);
+
+int perf_num_counters(void)
+{
+       return ARRAY_SIZE(event_map);
+}
+EXPORT_SYMBOL(perf_num_counters);
+
+static u64 bfin_pfmon_read(int idx)
+{
+       return bfin_read32(PFCNTR0 + (idx * 4));
+}
+
+static void bfin_pfmon_disable(struct hw_perf_event *hwc, int idx)
+{
+       bfin_write_PFCTL(bfin_read_PFCTL() & ~PFCEN(idx, PFCEN_MASK));
+}
+
+static void bfin_pfmon_enable(struct hw_perf_event *hwc, int idx)
+{
+       u32 val, mask;
+
+       val = PFPWR;
+       if (idx) {
+               mask = ~(PFCNT1 | PFMON1 | PFCEN1 | PEMUSW1);
+               /* The packed config is for event0, so shift it to event1 slots */
+               val |= (hwc->config << (PFMON1_P - PFMON0_P));
+               val |= (hwc->config & PFCNT0) << (PFCNT1_P - PFCNT0_P);
+               bfin_write_PFCNTR1(0);
+       } else {
+               mask = ~(PFCNT0 | PFMON0 | PFCEN0 | PEMUSW0);
+               val |= hwc->config;
+               bfin_write_PFCNTR0(0);
+       }
+
+       bfin_write_PFCTL((bfin_read_PFCTL() & mask) | val);
+}
+
+static void bfin_pfmon_disable_all(void)
+{
+       bfin_write_PFCTL(bfin_read_PFCTL() & ~PFPWR);
+}
+
+static void bfin_pfmon_enable_all(void)
+{
+       bfin_write_PFCTL(bfin_read_PFCTL() | PFPWR);
+}
+
+struct cpu_hw_events {
+       struct perf_event *events[MAX_HWEVENTS];
+       unsigned long used_mask[BITS_TO_LONGS(MAX_HWEVENTS)];
+};
+DEFINE_PER_CPU(struct cpu_hw_events, cpu_hw_events);
+
+static int hw_perf_cache_event(int config, int *evp)
+{
+       unsigned long type, op, result;
+       int ev;
+
+       /* unpack config */
+       type = config & 0xff;
+       op = (config >> 8) & 0xff;
+       result = (config >> 16) & 0xff;
+
+       if (type >= PERF_COUNT_HW_CACHE_MAX ||
+           op >= PERF_COUNT_HW_CACHE_OP_MAX ||
+           result >= PERF_COUNT_HW_CACHE_RESULT_MAX)
+               return -EINVAL;
+
+       ev = cache_events[type][op][result];
+       if (ev == 0)
+               return -EOPNOTSUPP;
+       if (ev == -1)
+               return -EINVAL;
+       *evp = ev;
+       return 0;
+}
+
+static void bfin_perf_event_update(struct perf_event *event,
+                                  struct hw_perf_event *hwc, int idx)
+{
+       u64 prev_raw_count, new_raw_count;
+       s64 delta;
+       int shift = 0;
+
+       /*
+        * Depending on the counter configuration, they may or may not
+        * be chained, in which case the previous counter value can be
+        * updated underneath us if the lower-half overflows.
+        *
+        * Our tactic to handle this is to first atomically read and
+        * exchange a new raw count - then add that new-prev delta
+        * count to the generic counter atomically.
+        *
+        * As there is no interrupt associated with the overflow events,
+        * this is the simplest approach for maintaining consistency.
+        */
+again:
+       prev_raw_count = local64_read(&hwc->prev_count);
+       new_raw_count = bfin_pfmon_read(idx);
+
+       if (local64_cmpxchg(&hwc->prev_count, prev_raw_count,
+                            new_raw_count) != prev_raw_count)
+               goto again;
+
+       /*
+        * Now we have the new raw value and have updated the prev
+        * timestamp already. We can now calculate the elapsed delta
+        * (counter-)time and add that to the generic counter.
+        *
+        * Careful, not all hw sign-extends above the physical width
+        * of the count.
+        */
+       delta = (new_raw_count << shift) - (prev_raw_count << shift);
+       delta >>= shift;
+
+       local64_add(delta, &event->count);
+}
+
+static void bfin_pmu_stop(struct perf_event *event, int flags)
+{
+       struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
+       struct hw_perf_event *hwc = &event->hw;
+       int idx = hwc->idx;
+
+       if (!(event->hw.state & PERF_HES_STOPPED)) {
+               bfin_pfmon_disable(hwc, idx);
+               cpuc->events[idx] = NULL;
+               event->hw.state |= PERF_HES_STOPPED;
+       }
+
+       if ((flags & PERF_EF_UPDATE) && !(event->hw.state & PERF_HES_UPTODATE)) {
+               bfin_perf_event_update(event, &event->hw, idx);
+               event->hw.state |= PERF_HES_UPTODATE;
+       }
+}
+
+static void bfin_pmu_start(struct perf_event *event, int flags)
+{
+       struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
+       struct hw_perf_event *hwc = &event->hw;
+       int idx = hwc->idx;
+
+       if (WARN_ON_ONCE(idx == -1))
+               return;
+
+       if (flags & PERF_EF_RELOAD)
+               WARN_ON_ONCE(!(event->hw.state & PERF_HES_UPTODATE));
+
+       cpuc->events[idx] = event;
+       event->hw.state = 0;
+       bfin_pfmon_enable(hwc, idx);
+}
+
+static void bfin_pmu_del(struct perf_event *event, int flags)
+{
+       struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
+
+       bfin_pmu_stop(event, PERF_EF_UPDATE);
+       __clear_bit(event->hw.idx, cpuc->used_mask);
+
+       perf_event_update_userpage(event);
+}
+
+static int bfin_pmu_add(struct perf_event *event, int flags)
+{
+       struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
+       struct hw_perf_event *hwc = &event->hw;
+       int idx = hwc->idx;
+       int ret = -EAGAIN;
+
+       perf_pmu_disable(event->pmu);
+
+       if (__test_and_set_bit(idx, cpuc->used_mask)) {
+               idx = find_first_zero_bit(cpuc->used_mask, MAX_HWEVENTS);
+               if (idx == MAX_HWEVENTS)
+                       goto out;
+
+               __set_bit(idx, cpuc->used_mask);
+               hwc->idx = idx;
+       }
+
+       bfin_pfmon_disable(hwc, idx);
+
+       event->hw.state = PERF_HES_UPTODATE | PERF_HES_STOPPED;
+       if (flags & PERF_EF_START)
+               bfin_pmu_start(event, PERF_EF_RELOAD);
+
+       perf_event_update_userpage(event);
+       ret = 0;
+out:
+       perf_pmu_enable(event->pmu);
+       return ret;
+}
+
+static void bfin_pmu_read(struct perf_event *event)
+{
+       bfin_perf_event_update(event, &event->hw, event->hw.idx);
+}
+
+static int bfin_pmu_event_init(struct perf_event *event)
+{
+       struct perf_event_attr *attr = &event->attr;
+       struct hw_perf_event *hwc = &event->hw;
+       int config = -1;
+       int ret;
+
+       if (attr->exclude_hv || attr->exclude_idle)
+               return -EPERM;
+
+       /*
+        * All of the on-chip counters are "limited", in that they have
+        * no interrupts, and are therefore unable to do sampling without
+        * further work and timer assistance.
+        */
+       if (hwc->sample_period)
+               return -EINVAL;
+
+       ret = 0;
+       switch (attr->type) {
+       case PERF_TYPE_RAW:
+               config = PFMON(0, attr->config & PFMON_MASK) |
+                       PFCNT(0, !(attr->config & 0x100));
+               break;
+       case PERF_TYPE_HW_CACHE:
+               ret = hw_perf_cache_event(attr->config, &config);
+               break;
+       case PERF_TYPE_HARDWARE:
+               if (attr->config >= ARRAY_SIZE(event_map))
+                       return -EINVAL;
+
+               config = event_map[attr->config];
+               break;
+       }
+
+       if (config == -1)
+               return -EINVAL;
+
+       if (!attr->exclude_kernel)
+               config |= PFCEN(0, PFCEN_ENABLE_SUPV);
+       if (!attr->exclude_user)
+               config |= PFCEN(0, PFCEN_ENABLE_USER);
+
+       hwc->config |= config;
+
+       return ret;
+}
+
+static void bfin_pmu_enable(struct pmu *pmu)
+{
+       struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
+       struct perf_event *event;
+       struct hw_perf_event *hwc;
+       int i;
+
+       for (i = 0; i < MAX_HWEVENTS; ++i) {
+               event = cpuc->events[i];
+               if (!event)
+                       continue;
+               hwc = &event->hw;
+               bfin_pfmon_enable(hwc, hwc->idx);
+       }
+
+       bfin_pfmon_enable_all();
+}
+
+static void bfin_pmu_disable(struct pmu *pmu)
+{
+       bfin_pfmon_disable_all();
+}
+
+static struct pmu pmu = {
+       .pmu_enable  = bfin_pmu_enable,
+       .pmu_disable = bfin_pmu_disable,
+       .event_init  = bfin_pmu_event_init,
+       .add         = bfin_pmu_add,
+       .del         = bfin_pmu_del,
+       .start       = bfin_pmu_start,
+       .stop        = bfin_pmu_stop,
+       .read        = bfin_pmu_read,
+};
+
+static void bfin_pmu_setup(int cpu)
+{
+       struct cpu_hw_events *cpuhw = &per_cpu(cpu_hw_events, cpu);
+
+       memset(cpuhw, 0, sizeof(struct cpu_hw_events));
+}
+
+static int __cpuinit
+bfin_pmu_notifier(struct notifier_block *self, unsigned long action, void *hcpu)
+{
+       unsigned int cpu = (long)hcpu;
+
+       switch (action & ~CPU_TASKS_FROZEN) {
+       case CPU_UP_PREPARE:
+               bfin_write_PFCTL(0);
+               bfin_pmu_setup(cpu);
+               break;
+
+       default:
+               break;
+       }
+
+       return NOTIFY_OK;
+}
+
+static int __init bfin_pmu_init(void)
+{
+       int ret;
+
+       ret = perf_pmu_register(&pmu, "cpu", PERF_TYPE_RAW);
+       if (!ret)
+               perf_cpu_notifier(bfin_pmu_notifier);
+
+       return ret;
+}
+early_initcall(bfin_pmu_init);