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-rw-r--r--kernel/perf_counter.c595
1 files changed, 398 insertions, 197 deletions
diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c
index 868102172aa4..d7cbc579fc80 100644
--- a/kernel/perf_counter.c
+++ b/kernel/perf_counter.c
@@ -50,7 +50,7 @@ static atomic_t nr_task_counters __read_mostly;
50 * 1 - disallow cpu counters to unpriv 50 * 1 - disallow cpu counters to unpriv
51 * 2 - disallow kernel profiling to unpriv 51 * 2 - disallow kernel profiling to unpriv
52 */ 52 */
53int sysctl_perf_counter_paranoid __read_mostly; 53int sysctl_perf_counter_paranoid __read_mostly = 1;
54 54
55static inline bool perf_paranoid_cpu(void) 55static inline bool perf_paranoid_cpu(void)
56{ 56{
@@ -88,6 +88,7 @@ void __weak hw_perf_disable(void) { barrier(); }
88void __weak hw_perf_enable(void) { barrier(); } 88void __weak hw_perf_enable(void) { barrier(); }
89 89
90void __weak hw_perf_counter_setup(int cpu) { barrier(); } 90void __weak hw_perf_counter_setup(int cpu) { barrier(); }
91void __weak hw_perf_counter_setup_online(int cpu) { barrier(); }
91 92
92int __weak 93int __weak
93hw_perf_group_sched_in(struct perf_counter *group_leader, 94hw_perf_group_sched_in(struct perf_counter *group_leader,
@@ -306,6 +307,10 @@ counter_sched_out(struct perf_counter *counter,
306 return; 307 return;
307 308
308 counter->state = PERF_COUNTER_STATE_INACTIVE; 309 counter->state = PERF_COUNTER_STATE_INACTIVE;
310 if (counter->pending_disable) {
311 counter->pending_disable = 0;
312 counter->state = PERF_COUNTER_STATE_OFF;
313 }
309 counter->tstamp_stopped = ctx->time; 314 counter->tstamp_stopped = ctx->time;
310 counter->pmu->disable(counter); 315 counter->pmu->disable(counter);
311 counter->oncpu = -1; 316 counter->oncpu = -1;
@@ -1498,10 +1503,21 @@ static void perf_counter_enable_on_exec(struct task_struct *task)
1498 */ 1503 */
1499static void __perf_counter_read(void *info) 1504static void __perf_counter_read(void *info)
1500{ 1505{
1506 struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
1501 struct perf_counter *counter = info; 1507 struct perf_counter *counter = info;
1502 struct perf_counter_context *ctx = counter->ctx; 1508 struct perf_counter_context *ctx = counter->ctx;
1503 unsigned long flags; 1509 unsigned long flags;
1504 1510
1511 /*
1512 * If this is a task context, we need to check whether it is
1513 * the current task context of this cpu. If not it has been
1514 * scheduled out before the smp call arrived. In that case
1515 * counter->count would have been updated to a recent sample
1516 * when the counter was scheduled out.
1517 */
1518 if (ctx->task && cpuctx->task_ctx != ctx)
1519 return;
1520
1505 local_irq_save(flags); 1521 local_irq_save(flags);
1506 if (ctx->is_active) 1522 if (ctx->is_active)
1507 update_context_time(ctx); 1523 update_context_time(ctx);
@@ -1691,7 +1707,32 @@ static int perf_release(struct inode *inode, struct file *file)
1691 return 0; 1707 return 0;
1692} 1708}
1693 1709
1694static u64 perf_counter_read_tree(struct perf_counter *counter) 1710static int perf_counter_read_size(struct perf_counter *counter)
1711{
1712 int entry = sizeof(u64); /* value */
1713 int size = 0;
1714 int nr = 1;
1715
1716 if (counter->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
1717 size += sizeof(u64);
1718
1719 if (counter->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
1720 size += sizeof(u64);
1721
1722 if (counter->attr.read_format & PERF_FORMAT_ID)
1723 entry += sizeof(u64);
1724
1725 if (counter->attr.read_format & PERF_FORMAT_GROUP) {
1726 nr += counter->group_leader->nr_siblings;
1727 size += sizeof(u64);
1728 }
1729
1730 size += entry * nr;
1731
1732 return size;
1733}
1734
1735static u64 perf_counter_read_value(struct perf_counter *counter)
1695{ 1736{
1696 struct perf_counter *child; 1737 struct perf_counter *child;
1697 u64 total = 0; 1738 u64 total = 0;
@@ -1703,14 +1744,96 @@ static u64 perf_counter_read_tree(struct perf_counter *counter)
1703 return total; 1744 return total;
1704} 1745}
1705 1746
1747static int perf_counter_read_entry(struct perf_counter *counter,
1748 u64 read_format, char __user *buf)
1749{
1750 int n = 0, count = 0;
1751 u64 values[2];
1752
1753 values[n++] = perf_counter_read_value(counter);
1754 if (read_format & PERF_FORMAT_ID)
1755 values[n++] = primary_counter_id(counter);
1756
1757 count = n * sizeof(u64);
1758
1759 if (copy_to_user(buf, values, count))
1760 return -EFAULT;
1761
1762 return count;
1763}
1764
1765static int perf_counter_read_group(struct perf_counter *counter,
1766 u64 read_format, char __user *buf)
1767{
1768 struct perf_counter *leader = counter->group_leader, *sub;
1769 int n = 0, size = 0, err = -EFAULT;
1770 u64 values[3];
1771
1772 values[n++] = 1 + leader->nr_siblings;
1773 if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
1774 values[n++] = leader->total_time_enabled +
1775 atomic64_read(&leader->child_total_time_enabled);
1776 }
1777 if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
1778 values[n++] = leader->total_time_running +
1779 atomic64_read(&leader->child_total_time_running);
1780 }
1781
1782 size = n * sizeof(u64);
1783
1784 if (copy_to_user(buf, values, size))
1785 return -EFAULT;
1786
1787 err = perf_counter_read_entry(leader, read_format, buf + size);
1788 if (err < 0)
1789 return err;
1790
1791 size += err;
1792
1793 list_for_each_entry(sub, &leader->sibling_list, list_entry) {
1794 err = perf_counter_read_entry(sub, read_format,
1795 buf + size);
1796 if (err < 0)
1797 return err;
1798
1799 size += err;
1800 }
1801
1802 return size;
1803}
1804
1805static int perf_counter_read_one(struct perf_counter *counter,
1806 u64 read_format, char __user *buf)
1807{
1808 u64 values[4];
1809 int n = 0;
1810
1811 values[n++] = perf_counter_read_value(counter);
1812 if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
1813 values[n++] = counter->total_time_enabled +
1814 atomic64_read(&counter->child_total_time_enabled);
1815 }
1816 if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
1817 values[n++] = counter->total_time_running +
1818 atomic64_read(&counter->child_total_time_running);
1819 }
1820 if (read_format & PERF_FORMAT_ID)
1821 values[n++] = primary_counter_id(counter);
1822
1823 if (copy_to_user(buf, values, n * sizeof(u64)))
1824 return -EFAULT;
1825
1826 return n * sizeof(u64);
1827}
1828
1706/* 1829/*
1707 * Read the performance counter - simple non blocking version for now 1830 * Read the performance counter - simple non blocking version for now
1708 */ 1831 */
1709static ssize_t 1832static ssize_t
1710perf_read_hw(struct perf_counter *counter, char __user *buf, size_t count) 1833perf_read_hw(struct perf_counter *counter, char __user *buf, size_t count)
1711{ 1834{
1712 u64 values[4]; 1835 u64 read_format = counter->attr.read_format;
1713 int n; 1836 int ret;
1714 1837
1715 /* 1838 /*
1716 * Return end-of-file for a read on a counter that is in 1839 * Return end-of-file for a read on a counter that is in
@@ -1720,28 +1843,18 @@ perf_read_hw(struct perf_counter *counter, char __user *buf, size_t count)
1720 if (counter->state == PERF_COUNTER_STATE_ERROR) 1843 if (counter->state == PERF_COUNTER_STATE_ERROR)
1721 return 0; 1844 return 0;
1722 1845
1846 if (count < perf_counter_read_size(counter))
1847 return -ENOSPC;
1848
1723 WARN_ON_ONCE(counter->ctx->parent_ctx); 1849 WARN_ON_ONCE(counter->ctx->parent_ctx);
1724 mutex_lock(&counter->child_mutex); 1850 mutex_lock(&counter->child_mutex);
1725 values[0] = perf_counter_read_tree(counter); 1851 if (read_format & PERF_FORMAT_GROUP)
1726 n = 1; 1852 ret = perf_counter_read_group(counter, read_format, buf);
1727 if (counter->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) 1853 else
1728 values[n++] = counter->total_time_enabled + 1854 ret = perf_counter_read_one(counter, read_format, buf);
1729 atomic64_read(&counter->child_total_time_enabled);
1730 if (counter->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
1731 values[n++] = counter->total_time_running +
1732 atomic64_read(&counter->child_total_time_running);
1733 if (counter->attr.read_format & PERF_FORMAT_ID)
1734 values[n++] = primary_counter_id(counter);
1735 mutex_unlock(&counter->child_mutex); 1855 mutex_unlock(&counter->child_mutex);
1736 1856
1737 if (count < n * sizeof(u64)) 1857 return ret;
1738 return -EINVAL;
1739 count = n * sizeof(u64);
1740
1741 if (copy_to_user(buf, values, count))
1742 return -EFAULT;
1743
1744 return count;
1745} 1858}
1746 1859
1747static ssize_t 1860static ssize_t
@@ -1906,6 +2019,10 @@ int perf_counter_task_disable(void)
1906 return 0; 2019 return 0;
1907} 2020}
1908 2021
2022#ifndef PERF_COUNTER_INDEX_OFFSET
2023# define PERF_COUNTER_INDEX_OFFSET 0
2024#endif
2025
1909static int perf_counter_index(struct perf_counter *counter) 2026static int perf_counter_index(struct perf_counter *counter)
1910{ 2027{
1911 if (counter->state != PERF_COUNTER_STATE_ACTIVE) 2028 if (counter->state != PERF_COUNTER_STATE_ACTIVE)
@@ -2245,7 +2362,7 @@ static void perf_pending_counter(struct perf_pending_entry *entry)
2245 2362
2246 if (counter->pending_disable) { 2363 if (counter->pending_disable) {
2247 counter->pending_disable = 0; 2364 counter->pending_disable = 0;
2248 perf_counter_disable(counter); 2365 __perf_counter_disable(counter);
2249 } 2366 }
2250 2367
2251 if (counter->pending_wakeup) { 2368 if (counter->pending_wakeup) {
@@ -2630,7 +2747,80 @@ static u32 perf_counter_tid(struct perf_counter *counter, struct task_struct *p)
2630 return task_pid_nr_ns(p, counter->ns); 2747 return task_pid_nr_ns(p, counter->ns);
2631} 2748}
2632 2749
2633static void perf_counter_output(struct perf_counter *counter, int nmi, 2750static void perf_output_read_one(struct perf_output_handle *handle,
2751 struct perf_counter *counter)
2752{
2753 u64 read_format = counter->attr.read_format;
2754 u64 values[4];
2755 int n = 0;
2756
2757 values[n++] = atomic64_read(&counter->count);
2758 if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
2759 values[n++] = counter->total_time_enabled +
2760 atomic64_read(&counter->child_total_time_enabled);
2761 }
2762 if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
2763 values[n++] = counter->total_time_running +
2764 atomic64_read(&counter->child_total_time_running);
2765 }
2766 if (read_format & PERF_FORMAT_ID)
2767 values[n++] = primary_counter_id(counter);
2768
2769 perf_output_copy(handle, values, n * sizeof(u64));
2770}
2771
2772/*
2773 * XXX PERF_FORMAT_GROUP vs inherited counters seems difficult.
2774 */
2775static void perf_output_read_group(struct perf_output_handle *handle,
2776 struct perf_counter *counter)
2777{
2778 struct perf_counter *leader = counter->group_leader, *sub;
2779 u64 read_format = counter->attr.read_format;
2780 u64 values[5];
2781 int n = 0;
2782
2783 values[n++] = 1 + leader->nr_siblings;
2784
2785 if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
2786 values[n++] = leader->total_time_enabled;
2787
2788 if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
2789 values[n++] = leader->total_time_running;
2790
2791 if (leader != counter)
2792 leader->pmu->read(leader);
2793
2794 values[n++] = atomic64_read(&leader->count);
2795 if (read_format & PERF_FORMAT_ID)
2796 values[n++] = primary_counter_id(leader);
2797
2798 perf_output_copy(handle, values, n * sizeof(u64));
2799
2800 list_for_each_entry(sub, &leader->sibling_list, list_entry) {
2801 n = 0;
2802
2803 if (sub != counter)
2804 sub->pmu->read(sub);
2805
2806 values[n++] = atomic64_read(&sub->count);
2807 if (read_format & PERF_FORMAT_ID)
2808 values[n++] = primary_counter_id(sub);
2809
2810 perf_output_copy(handle, values, n * sizeof(u64));
2811 }
2812}
2813
2814static void perf_output_read(struct perf_output_handle *handle,
2815 struct perf_counter *counter)
2816{
2817 if (counter->attr.read_format & PERF_FORMAT_GROUP)
2818 perf_output_read_group(handle, counter);
2819 else
2820 perf_output_read_one(handle, counter);
2821}
2822
2823void perf_counter_output(struct perf_counter *counter, int nmi,
2634 struct perf_sample_data *data) 2824 struct perf_sample_data *data)
2635{ 2825{
2636 int ret; 2826 int ret;
@@ -2641,12 +2831,7 @@ static void perf_counter_output(struct perf_counter *counter, int nmi,
2641 struct { 2831 struct {
2642 u32 pid, tid; 2832 u32 pid, tid;
2643 } tid_entry; 2833 } tid_entry;
2644 struct {
2645 u64 id;
2646 u64 counter;
2647 } group_entry;
2648 struct perf_callchain_entry *callchain = NULL; 2834 struct perf_callchain_entry *callchain = NULL;
2649 struct perf_tracepoint_record *tp;
2650 int callchain_size = 0; 2835 int callchain_size = 0;
2651 u64 time; 2836 u64 time;
2652 struct { 2837 struct {
@@ -2700,10 +2885,8 @@ static void perf_counter_output(struct perf_counter *counter, int nmi,
2700 if (sample_type & PERF_SAMPLE_PERIOD) 2885 if (sample_type & PERF_SAMPLE_PERIOD)
2701 header.size += sizeof(u64); 2886 header.size += sizeof(u64);
2702 2887
2703 if (sample_type & PERF_SAMPLE_GROUP) { 2888 if (sample_type & PERF_SAMPLE_READ)
2704 header.size += sizeof(u64) + 2889 header.size += perf_counter_read_size(counter);
2705 counter->nr_siblings * sizeof(group_entry);
2706 }
2707 2890
2708 if (sample_type & PERF_SAMPLE_CALLCHAIN) { 2891 if (sample_type & PERF_SAMPLE_CALLCHAIN) {
2709 callchain = perf_callchain(data->regs); 2892 callchain = perf_callchain(data->regs);
@@ -2715,9 +2898,16 @@ static void perf_counter_output(struct perf_counter *counter, int nmi,
2715 header.size += sizeof(u64); 2898 header.size += sizeof(u64);
2716 } 2899 }
2717 2900
2718 if (sample_type & PERF_SAMPLE_TP_RECORD) { 2901 if (sample_type & PERF_SAMPLE_RAW) {
2719 tp = data->private; 2902 int size = sizeof(u32);
2720 header.size += tp->size; 2903
2904 if (data->raw)
2905 size += data->raw->size;
2906 else
2907 size += sizeof(u32);
2908
2909 WARN_ON_ONCE(size & (sizeof(u64)-1));
2910 header.size += size;
2721 } 2911 }
2722 2912
2723 ret = perf_output_begin(&handle, counter, header.size, nmi, 1); 2913 ret = perf_output_begin(&handle, counter, header.size, nmi, 1);
@@ -2753,26 +2943,8 @@ static void perf_counter_output(struct perf_counter *counter, int nmi,
2753 if (sample_type & PERF_SAMPLE_PERIOD) 2943 if (sample_type & PERF_SAMPLE_PERIOD)
2754 perf_output_put(&handle, data->period); 2944 perf_output_put(&handle, data->period);
2755 2945
2756 /* 2946 if (sample_type & PERF_SAMPLE_READ)
2757 * XXX PERF_SAMPLE_GROUP vs inherited counters seems difficult. 2947 perf_output_read(&handle, counter);
2758 */
2759 if (sample_type & PERF_SAMPLE_GROUP) {
2760 struct perf_counter *leader, *sub;
2761 u64 nr = counter->nr_siblings;
2762
2763 perf_output_put(&handle, nr);
2764
2765 leader = counter->group_leader;
2766 list_for_each_entry(sub, &leader->sibling_list, list_entry) {
2767 if (sub != counter)
2768 sub->pmu->read(sub);
2769
2770 group_entry.id = primary_counter_id(sub);
2771 group_entry.counter = atomic64_read(&sub->count);
2772
2773 perf_output_put(&handle, group_entry);
2774 }
2775 }
2776 2948
2777 if (sample_type & PERF_SAMPLE_CALLCHAIN) { 2949 if (sample_type & PERF_SAMPLE_CALLCHAIN) {
2778 if (callchain) 2950 if (callchain)
@@ -2783,8 +2955,21 @@ static void perf_counter_output(struct perf_counter *counter, int nmi,
2783 } 2955 }
2784 } 2956 }
2785 2957
2786 if (sample_type & PERF_SAMPLE_TP_RECORD) 2958 if (sample_type & PERF_SAMPLE_RAW) {
2787 perf_output_copy(&handle, tp->record, tp->size); 2959 if (data->raw) {
2960 perf_output_put(&handle, data->raw->size);
2961 perf_output_copy(&handle, data->raw->data, data->raw->size);
2962 } else {
2963 struct {
2964 u32 size;
2965 u32 data;
2966 } raw = {
2967 .size = sizeof(u32),
2968 .data = 0,
2969 };
2970 perf_output_put(&handle, raw);
2971 }
2972 }
2788 2973
2789 perf_output_end(&handle); 2974 perf_output_end(&handle);
2790} 2975}
@@ -2798,8 +2983,6 @@ struct perf_read_event {
2798 2983
2799 u32 pid; 2984 u32 pid;
2800 u32 tid; 2985 u32 tid;
2801 u64 value;
2802 u64 format[3];
2803}; 2986};
2804 2987
2805static void 2988static void
@@ -2811,34 +2994,20 @@ perf_counter_read_event(struct perf_counter *counter,
2811 .header = { 2994 .header = {
2812 .type = PERF_EVENT_READ, 2995 .type = PERF_EVENT_READ,
2813 .misc = 0, 2996 .misc = 0,
2814 .size = sizeof(event) - sizeof(event.format), 2997 .size = sizeof(event) + perf_counter_read_size(counter),
2815 }, 2998 },
2816 .pid = perf_counter_pid(counter, task), 2999 .pid = perf_counter_pid(counter, task),
2817 .tid = perf_counter_tid(counter, task), 3000 .tid = perf_counter_tid(counter, task),
2818 .value = atomic64_read(&counter->count),
2819 }; 3001 };
2820 int ret, i = 0; 3002 int ret;
2821
2822 if (counter->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
2823 event.header.size += sizeof(u64);
2824 event.format[i++] = counter->total_time_enabled;
2825 }
2826
2827 if (counter->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
2828 event.header.size += sizeof(u64);
2829 event.format[i++] = counter->total_time_running;
2830 }
2831
2832 if (counter->attr.read_format & PERF_FORMAT_ID) {
2833 event.header.size += sizeof(u64);
2834 event.format[i++] = primary_counter_id(counter);
2835 }
2836 3003
2837 ret = perf_output_begin(&handle, counter, event.header.size, 0, 0); 3004 ret = perf_output_begin(&handle, counter, event.header.size, 0, 0);
2838 if (ret) 3005 if (ret)
2839 return; 3006 return;
2840 3007
2841 perf_output_copy(&handle, &event, event.header.size); 3008 perf_output_put(&handle, event);
3009 perf_output_read(&handle, counter);
3010
2842 perf_output_end(&handle); 3011 perf_output_end(&handle);
2843} 3012}
2844 3013
@@ -2849,7 +3018,8 @@ perf_counter_read_event(struct perf_counter *counter,
2849 */ 3018 */
2850 3019
2851struct perf_task_event { 3020struct perf_task_event {
2852 struct task_struct *task; 3021 struct task_struct *task;
3022 struct perf_counter_context *task_ctx;
2853 3023
2854 struct { 3024 struct {
2855 struct perf_event_header header; 3025 struct perf_event_header header;
@@ -2873,10 +3043,10 @@ static void perf_counter_task_output(struct perf_counter *counter,
2873 return; 3043 return;
2874 3044
2875 task_event->event.pid = perf_counter_pid(counter, task); 3045 task_event->event.pid = perf_counter_pid(counter, task);
2876 task_event->event.ppid = perf_counter_pid(counter, task->real_parent); 3046 task_event->event.ppid = perf_counter_pid(counter, current);
2877 3047
2878 task_event->event.tid = perf_counter_tid(counter, task); 3048 task_event->event.tid = perf_counter_tid(counter, task);
2879 task_event->event.ptid = perf_counter_tid(counter, task->real_parent); 3049 task_event->event.ptid = perf_counter_tid(counter, current);
2880 3050
2881 perf_output_put(&handle, task_event->event); 3051 perf_output_put(&handle, task_event->event);
2882 perf_output_end(&handle); 3052 perf_output_end(&handle);
@@ -2909,24 +3079,23 @@ static void perf_counter_task_ctx(struct perf_counter_context *ctx,
2909static void perf_counter_task_event(struct perf_task_event *task_event) 3079static void perf_counter_task_event(struct perf_task_event *task_event)
2910{ 3080{
2911 struct perf_cpu_context *cpuctx; 3081 struct perf_cpu_context *cpuctx;
2912 struct perf_counter_context *ctx; 3082 struct perf_counter_context *ctx = task_event->task_ctx;
2913 3083
2914 cpuctx = &get_cpu_var(perf_cpu_context); 3084 cpuctx = &get_cpu_var(perf_cpu_context);
2915 perf_counter_task_ctx(&cpuctx->ctx, task_event); 3085 perf_counter_task_ctx(&cpuctx->ctx, task_event);
2916 put_cpu_var(perf_cpu_context); 3086 put_cpu_var(perf_cpu_context);
2917 3087
2918 rcu_read_lock(); 3088 rcu_read_lock();
2919 /* 3089 if (!ctx)
2920 * doesn't really matter which of the child contexts the 3090 ctx = rcu_dereference(task_event->task->perf_counter_ctxp);
2921 * events ends up in.
2922 */
2923 ctx = rcu_dereference(current->perf_counter_ctxp);
2924 if (ctx) 3091 if (ctx)
2925 perf_counter_task_ctx(ctx, task_event); 3092 perf_counter_task_ctx(ctx, task_event);
2926 rcu_read_unlock(); 3093 rcu_read_unlock();
2927} 3094}
2928 3095
2929static void perf_counter_task(struct task_struct *task, int new) 3096static void perf_counter_task(struct task_struct *task,
3097 struct perf_counter_context *task_ctx,
3098 int new)
2930{ 3099{
2931 struct perf_task_event task_event; 3100 struct perf_task_event task_event;
2932 3101
@@ -2936,8 +3105,9 @@ static void perf_counter_task(struct task_struct *task, int new)
2936 return; 3105 return;
2937 3106
2938 task_event = (struct perf_task_event){ 3107 task_event = (struct perf_task_event){
2939 .task = task, 3108 .task = task,
2940 .event = { 3109 .task_ctx = task_ctx,
3110 .event = {
2941 .header = { 3111 .header = {
2942 .type = new ? PERF_EVENT_FORK : PERF_EVENT_EXIT, 3112 .type = new ? PERF_EVENT_FORK : PERF_EVENT_EXIT,
2943 .misc = 0, 3113 .misc = 0,
@@ -2955,7 +3125,7 @@ static void perf_counter_task(struct task_struct *task, int new)
2955 3125
2956void perf_counter_fork(struct task_struct *task) 3126void perf_counter_fork(struct task_struct *task)
2957{ 3127{
2958 perf_counter_task(task, 1); 3128 perf_counter_task(task, NULL, 1);
2959} 3129}
2960 3130
2961/* 3131/*
@@ -3344,125 +3514,111 @@ int perf_counter_overflow(struct perf_counter *counter, int nmi,
3344 * Generic software counter infrastructure 3514 * Generic software counter infrastructure
3345 */ 3515 */
3346 3516
3347static void perf_swcounter_update(struct perf_counter *counter) 3517/*
3518 * We directly increment counter->count and keep a second value in
3519 * counter->hw.period_left to count intervals. This period counter
3520 * is kept in the range [-sample_period, 0] so that we can use the
3521 * sign as trigger.
3522 */
3523
3524static u64 perf_swcounter_set_period(struct perf_counter *counter)
3348{ 3525{
3349 struct hw_perf_counter *hwc = &counter->hw; 3526 struct hw_perf_counter *hwc = &counter->hw;
3350 u64 prev, now; 3527 u64 period = hwc->last_period;
3351 s64 delta; 3528 u64 nr, offset;
3529 s64 old, val;
3530
3531 hwc->last_period = hwc->sample_period;
3352 3532
3353again: 3533again:
3354 prev = atomic64_read(&hwc->prev_count); 3534 old = val = atomic64_read(&hwc->period_left);
3355 now = atomic64_read(&hwc->count); 3535 if (val < 0)
3356 if (atomic64_cmpxchg(&hwc->prev_count, prev, now) != prev) 3536 return 0;
3357 goto again;
3358 3537
3359 delta = now - prev; 3538 nr = div64_u64(period + val, period);
3539 offset = nr * period;
3540 val -= offset;
3541 if (atomic64_cmpxchg(&hwc->period_left, old, val) != old)
3542 goto again;
3360 3543
3361 atomic64_add(delta, &counter->count); 3544 return nr;
3362 atomic64_sub(delta, &hwc->period_left);
3363} 3545}
3364 3546
3365static void perf_swcounter_set_period(struct perf_counter *counter) 3547static void perf_swcounter_overflow(struct perf_counter *counter,
3548 int nmi, struct perf_sample_data *data)
3366{ 3549{
3367 struct hw_perf_counter *hwc = &counter->hw; 3550 struct hw_perf_counter *hwc = &counter->hw;
3368 s64 left = atomic64_read(&hwc->period_left); 3551 u64 overflow;
3369 s64 period = hwc->sample_period;
3370 3552
3371 if (unlikely(left <= -period)) { 3553 data->period = counter->hw.last_period;
3372 left = period; 3554 overflow = perf_swcounter_set_period(counter);
3373 atomic64_set(&hwc->period_left, left);
3374 hwc->last_period = period;
3375 }
3376 3555
3377 if (unlikely(left <= 0)) { 3556 if (hwc->interrupts == MAX_INTERRUPTS)
3378 left += period; 3557 return;
3379 atomic64_add(period, &hwc->period_left);
3380 hwc->last_period = period;
3381 }
3382 3558
3383 atomic64_set(&hwc->prev_count, -left); 3559 for (; overflow; overflow--) {
3384 atomic64_set(&hwc->count, -left); 3560 if (perf_counter_overflow(counter, nmi, data)) {
3561 /*
3562 * We inhibit the overflow from happening when
3563 * hwc->interrupts == MAX_INTERRUPTS.
3564 */
3565 break;
3566 }
3567 }
3385} 3568}
3386 3569
3387static enum hrtimer_restart perf_swcounter_hrtimer(struct hrtimer *hrtimer) 3570static void perf_swcounter_unthrottle(struct perf_counter *counter)
3388{ 3571{
3389 enum hrtimer_restart ret = HRTIMER_RESTART;
3390 struct perf_sample_data data;
3391 struct perf_counter *counter;
3392 u64 period;
3393
3394 counter = container_of(hrtimer, struct perf_counter, hw.hrtimer);
3395 counter->pmu->read(counter);
3396
3397 data.addr = 0;
3398 data.regs = get_irq_regs();
3399 /* 3572 /*
3400 * In case we exclude kernel IPs or are somehow not in interrupt 3573 * Nothing to do, we already reset hwc->interrupts.
3401 * context, provide the next best thing, the user IP.
3402 */ 3574 */
3403 if ((counter->attr.exclude_kernel || !data.regs) && 3575}
3404 !counter->attr.exclude_user)
3405 data.regs = task_pt_regs(current);
3406 3576
3407 if (data.regs) { 3577static void perf_swcounter_add(struct perf_counter *counter, u64 nr,
3408 if (perf_counter_overflow(counter, 0, &data)) 3578 int nmi, struct perf_sample_data *data)
3409 ret = HRTIMER_NORESTART; 3579{
3410 } 3580 struct hw_perf_counter *hwc = &counter->hw;
3411 3581
3412 period = max_t(u64, 10000, counter->hw.sample_period); 3582 atomic64_add(nr, &counter->count);
3413 hrtimer_forward_now(hrtimer, ns_to_ktime(period));
3414 3583
3415 return ret; 3584 if (!hwc->sample_period)
3416} 3585 return;
3417 3586
3418static void perf_swcounter_overflow(struct perf_counter *counter, 3587 if (!data->regs)
3419 int nmi, struct perf_sample_data *data) 3588 return;
3420{
3421 data->period = counter->hw.last_period;
3422 3589
3423 perf_swcounter_update(counter); 3590 if (!atomic64_add_negative(nr, &hwc->period_left))
3424 perf_swcounter_set_period(counter); 3591 perf_swcounter_overflow(counter, nmi, data);
3425 if (perf_counter_overflow(counter, nmi, data))
3426 /* soft-disable the counter */
3427 ;
3428} 3592}
3429 3593
3430static int perf_swcounter_is_counting(struct perf_counter *counter) 3594static int perf_swcounter_is_counting(struct perf_counter *counter)
3431{ 3595{
3432 struct perf_counter_context *ctx; 3596 /*
3433 unsigned long flags; 3597 * The counter is active, we're good!
3434 int count; 3598 */
3435
3436 if (counter->state == PERF_COUNTER_STATE_ACTIVE) 3599 if (counter->state == PERF_COUNTER_STATE_ACTIVE)
3437 return 1; 3600 return 1;
3438 3601
3602 /*
3603 * The counter is off/error, not counting.
3604 */
3439 if (counter->state != PERF_COUNTER_STATE_INACTIVE) 3605 if (counter->state != PERF_COUNTER_STATE_INACTIVE)
3440 return 0; 3606 return 0;
3441 3607
3442 /* 3608 /*
3443 * If the counter is inactive, it could be just because 3609 * The counter is inactive, if the context is active
3444 * its task is scheduled out, or because it's in a group 3610 * we're part of a group that didn't make it on the 'pmu',
3445 * which could not go on the PMU. We want to count in 3611 * not counting.
3446 * the first case but not the second. If the context is
3447 * currently active then an inactive software counter must
3448 * be the second case. If it's not currently active then
3449 * we need to know whether the counter was active when the
3450 * context was last active, which we can determine by
3451 * comparing counter->tstamp_stopped with ctx->time.
3452 *
3453 * We are within an RCU read-side critical section,
3454 * which protects the existence of *ctx.
3455 */ 3612 */
3456 ctx = counter->ctx; 3613 if (counter->ctx->is_active)
3457 spin_lock_irqsave(&ctx->lock, flags); 3614 return 0;
3458 count = 1; 3615
3459 /* Re-check state now we have the lock */ 3616 /*
3460 if (counter->state < PERF_COUNTER_STATE_INACTIVE || 3617 * We're inactive and the context is too, this means the
3461 counter->ctx->is_active || 3618 * task is scheduled out, we're counting events that happen
3462 counter->tstamp_stopped < ctx->time) 3619 * to us, like migration events.
3463 count = 0; 3620 */
3464 spin_unlock_irqrestore(&ctx->lock, flags); 3621 return 1;
3465 return count;
3466} 3622}
3467 3623
3468static int perf_swcounter_match(struct perf_counter *counter, 3624static int perf_swcounter_match(struct perf_counter *counter,
@@ -3488,15 +3644,6 @@ static int perf_swcounter_match(struct perf_counter *counter,
3488 return 1; 3644 return 1;
3489} 3645}
3490 3646
3491static void perf_swcounter_add(struct perf_counter *counter, u64 nr,
3492 int nmi, struct perf_sample_data *data)
3493{
3494 int neg = atomic64_add_negative(nr, &counter->hw.count);
3495
3496 if (counter->hw.sample_period && !neg && data->regs)
3497 perf_swcounter_overflow(counter, nmi, data);
3498}
3499
3500static void perf_swcounter_ctx_event(struct perf_counter_context *ctx, 3647static void perf_swcounter_ctx_event(struct perf_counter_context *ctx,
3501 enum perf_type_id type, 3648 enum perf_type_id type,
3502 u32 event, u64 nr, int nmi, 3649 u32 event, u64 nr, int nmi,
@@ -3575,27 +3722,66 @@ void __perf_swcounter_event(u32 event, u64 nr, int nmi,
3575 3722
3576static void perf_swcounter_read(struct perf_counter *counter) 3723static void perf_swcounter_read(struct perf_counter *counter)
3577{ 3724{
3578 perf_swcounter_update(counter);
3579} 3725}
3580 3726
3581static int perf_swcounter_enable(struct perf_counter *counter) 3727static int perf_swcounter_enable(struct perf_counter *counter)
3582{ 3728{
3583 perf_swcounter_set_period(counter); 3729 struct hw_perf_counter *hwc = &counter->hw;
3730
3731 if (hwc->sample_period) {
3732 hwc->last_period = hwc->sample_period;
3733 perf_swcounter_set_period(counter);
3734 }
3584 return 0; 3735 return 0;
3585} 3736}
3586 3737
3587static void perf_swcounter_disable(struct perf_counter *counter) 3738static void perf_swcounter_disable(struct perf_counter *counter)
3588{ 3739{
3589 perf_swcounter_update(counter);
3590} 3740}
3591 3741
3592static const struct pmu perf_ops_generic = { 3742static const struct pmu perf_ops_generic = {
3593 .enable = perf_swcounter_enable, 3743 .enable = perf_swcounter_enable,
3594 .disable = perf_swcounter_disable, 3744 .disable = perf_swcounter_disable,
3595 .read = perf_swcounter_read, 3745 .read = perf_swcounter_read,
3746 .unthrottle = perf_swcounter_unthrottle,
3596}; 3747};
3597 3748
3598/* 3749/*
3750 * hrtimer based swcounter callback
3751 */
3752
3753static enum hrtimer_restart perf_swcounter_hrtimer(struct hrtimer *hrtimer)
3754{
3755 enum hrtimer_restart ret = HRTIMER_RESTART;
3756 struct perf_sample_data data;
3757 struct perf_counter *counter;
3758 u64 period;
3759
3760 counter = container_of(hrtimer, struct perf_counter, hw.hrtimer);
3761 counter->pmu->read(counter);
3762
3763 data.addr = 0;
3764 data.regs = get_irq_regs();
3765 /*
3766 * In case we exclude kernel IPs or are somehow not in interrupt
3767 * context, provide the next best thing, the user IP.
3768 */
3769 if ((counter->attr.exclude_kernel || !data.regs) &&
3770 !counter->attr.exclude_user)
3771 data.regs = task_pt_regs(current);
3772
3773 if (data.regs) {
3774 if (perf_counter_overflow(counter, 0, &data))
3775 ret = HRTIMER_NORESTART;
3776 }
3777
3778 period = max_t(u64, 10000, counter->hw.sample_period);
3779 hrtimer_forward_now(hrtimer, ns_to_ktime(period));
3780
3781 return ret;
3782}
3783
3784/*
3599 * Software counter: cpu wall time clock 3785 * Software counter: cpu wall time clock
3600 */ 3786 */
3601 3787
@@ -3715,15 +3901,15 @@ static const struct pmu perf_ops_task_clock = {
3715void perf_tpcounter_event(int event_id, u64 addr, u64 count, void *record, 3901void perf_tpcounter_event(int event_id, u64 addr, u64 count, void *record,
3716 int entry_size) 3902 int entry_size)
3717{ 3903{
3718 struct perf_tracepoint_record tp = { 3904 struct perf_raw_record raw = {
3719 .size = entry_size, 3905 .size = entry_size,
3720 .record = record, 3906 .data = record,
3721 }; 3907 };
3722 3908
3723 struct perf_sample_data data = { 3909 struct perf_sample_data data = {
3724 .regs = get_irq_regs(), 3910 .regs = get_irq_regs(),
3725 .addr = addr, 3911 .addr = addr,
3726 .private = &tp, 3912 .raw = &raw,
3727 }; 3913 };
3728 3914
3729 if (!data.regs) 3915 if (!data.regs)
@@ -3743,6 +3929,14 @@ static void tp_perf_counter_destroy(struct perf_counter *counter)
3743 3929
3744static const struct pmu *tp_perf_counter_init(struct perf_counter *counter) 3930static const struct pmu *tp_perf_counter_init(struct perf_counter *counter)
3745{ 3931{
3932 /*
3933 * Raw tracepoint data is a severe data leak, only allow root to
3934 * have these.
3935 */
3936 if ((counter->attr.sample_type & PERF_SAMPLE_RAW) &&
3937 !capable(CAP_SYS_ADMIN))
3938 return ERR_PTR(-EPERM);
3939
3746 if (ftrace_profile_enable(counter->attr.config)) 3940 if (ftrace_profile_enable(counter->attr.config))
3747 return NULL; 3941 return NULL;
3748 3942
@@ -3872,13 +4066,14 @@ perf_counter_alloc(struct perf_counter_attr *attr,
3872 hwc->sample_period = attr->sample_period; 4066 hwc->sample_period = attr->sample_period;
3873 if (attr->freq && attr->sample_freq) 4067 if (attr->freq && attr->sample_freq)
3874 hwc->sample_period = 1; 4068 hwc->sample_period = 1;
4069 hwc->last_period = hwc->sample_period;
3875 4070
3876 atomic64_set(&hwc->period_left, hwc->sample_period); 4071 atomic64_set(&hwc->period_left, hwc->sample_period);
3877 4072
3878 /* 4073 /*
3879 * we currently do not support PERF_SAMPLE_GROUP on inherited counters 4074 * we currently do not support PERF_FORMAT_GROUP on inherited counters
3880 */ 4075 */
3881 if (attr->inherit && (attr->sample_type & PERF_SAMPLE_GROUP)) 4076 if (attr->inherit && (attr->read_format & PERF_FORMAT_GROUP))
3882 goto done; 4077 goto done;
3883 4078
3884 switch (attr->type) { 4079 switch (attr->type) {
@@ -4285,7 +4480,7 @@ void perf_counter_exit_task(struct task_struct *child)
4285 unsigned long flags; 4480 unsigned long flags;
4286 4481
4287 if (likely(!child->perf_counter_ctxp)) { 4482 if (likely(!child->perf_counter_ctxp)) {
4288 perf_counter_task(child, 0); 4483 perf_counter_task(child, NULL, 0);
4289 return; 4484 return;
4290 } 4485 }
4291 4486
@@ -4305,6 +4500,7 @@ void perf_counter_exit_task(struct task_struct *child)
4305 * incremented the context's refcount before we do put_ctx below. 4500 * incremented the context's refcount before we do put_ctx below.
4306 */ 4501 */
4307 spin_lock(&child_ctx->lock); 4502 spin_lock(&child_ctx->lock);
4503 child->perf_counter_ctxp = NULL;
4308 /* 4504 /*
4309 * If this context is a clone; unclone it so it can't get 4505 * If this context is a clone; unclone it so it can't get
4310 * swapped to another process while we're removing all 4506 * swapped to another process while we're removing all
@@ -4318,9 +4514,7 @@ void perf_counter_exit_task(struct task_struct *child)
4318 * won't get any samples after PERF_EVENT_EXIT. We can however still 4514 * won't get any samples after PERF_EVENT_EXIT. We can however still
4319 * get a few PERF_EVENT_READ events. 4515 * get a few PERF_EVENT_READ events.
4320 */ 4516 */
4321 perf_counter_task(child, 0); 4517 perf_counter_task(child, child_ctx, 0);
4322
4323 child->perf_counter_ctxp = NULL;
4324 4518
4325 /* 4519 /*
4326 * We can recurse on the same lock type through: 4520 * We can recurse on the same lock type through:
@@ -4541,6 +4735,11 @@ perf_cpu_notify(struct notifier_block *self, unsigned long action, void *hcpu)
4541 perf_counter_init_cpu(cpu); 4735 perf_counter_init_cpu(cpu);
4542 break; 4736 break;
4543 4737
4738 case CPU_ONLINE:
4739 case CPU_ONLINE_FROZEN:
4740 hw_perf_counter_setup_online(cpu);
4741 break;
4742
4544 case CPU_DOWN_PREPARE: 4743 case CPU_DOWN_PREPARE:
4545 case CPU_DOWN_PREPARE_FROZEN: 4744 case CPU_DOWN_PREPARE_FROZEN:
4546 perf_counter_exit_cpu(cpu); 4745 perf_counter_exit_cpu(cpu);
@@ -4565,6 +4764,8 @@ void __init perf_counter_init(void)
4565{ 4764{
4566 perf_cpu_notify(&perf_cpu_nb, (unsigned long)CPU_UP_PREPARE, 4765 perf_cpu_notify(&perf_cpu_nb, (unsigned long)CPU_UP_PREPARE,
4567 (void *)(long)smp_processor_id()); 4766 (void *)(long)smp_processor_id());
4767 perf_cpu_notify(&perf_cpu_nb, (unsigned long)CPU_ONLINE,
4768 (void *)(long)smp_processor_id());
4568 register_cpu_notifier(&perf_cpu_nb); 4769 register_cpu_notifier(&perf_cpu_nb);
4569} 4770}
4570 4771