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-rw-r--r--kernel/perf_event.c965
1 files changed, 662 insertions, 303 deletions
diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index 0f86feb6db0c..6b7ddba1dd64 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -20,6 +20,7 @@
20#include <linux/percpu.h> 20#include <linux/percpu.h>
21#include <linux/ptrace.h> 21#include <linux/ptrace.h>
22#include <linux/vmstat.h> 22#include <linux/vmstat.h>
23#include <linux/vmalloc.h>
23#include <linux/hardirq.h> 24#include <linux/hardirq.h>
24#include <linux/rculist.h> 25#include <linux/rculist.h>
25#include <linux/uaccess.h> 26#include <linux/uaccess.h>
@@ -27,6 +28,8 @@
27#include <linux/anon_inodes.h> 28#include <linux/anon_inodes.h>
28#include <linux/kernel_stat.h> 29#include <linux/kernel_stat.h>
29#include <linux/perf_event.h> 30#include <linux/perf_event.h>
31#include <linux/ftrace_event.h>
32#include <linux/hw_breakpoint.h>
30 33
31#include <asm/irq_regs.h> 34#include <asm/irq_regs.h>
32 35
@@ -243,6 +246,49 @@ static void perf_unpin_context(struct perf_event_context *ctx)
243 put_ctx(ctx); 246 put_ctx(ctx);
244} 247}
245 248
249static inline u64 perf_clock(void)
250{
251 return cpu_clock(smp_processor_id());
252}
253
254/*
255 * Update the record of the current time in a context.
256 */
257static void update_context_time(struct perf_event_context *ctx)
258{
259 u64 now = perf_clock();
260
261 ctx->time += now - ctx->timestamp;
262 ctx->timestamp = now;
263}
264
265/*
266 * Update the total_time_enabled and total_time_running fields for a event.
267 */
268static void update_event_times(struct perf_event *event)
269{
270 struct perf_event_context *ctx = event->ctx;
271 u64 run_end;
272
273 if (event->state < PERF_EVENT_STATE_INACTIVE ||
274 event->group_leader->state < PERF_EVENT_STATE_INACTIVE)
275 return;
276
277 if (ctx->is_active)
278 run_end = ctx->time;
279 else
280 run_end = event->tstamp_stopped;
281
282 event->total_time_enabled = run_end - event->tstamp_enabled;
283
284 if (event->state == PERF_EVENT_STATE_INACTIVE)
285 run_end = event->tstamp_stopped;
286 else
287 run_end = ctx->time;
288
289 event->total_time_running = run_end - event->tstamp_running;
290}
291
246/* 292/*
247 * Add a event from the lists for its context. 293 * Add a event from the lists for its context.
248 * Must be called with ctx->mutex and ctx->lock held. 294 * Must be called with ctx->mutex and ctx->lock held.
@@ -291,6 +337,18 @@ list_del_event(struct perf_event *event, struct perf_event_context *ctx)
291 if (event->group_leader != event) 337 if (event->group_leader != event)
292 event->group_leader->nr_siblings--; 338 event->group_leader->nr_siblings--;
293 339
340 update_event_times(event);
341
342 /*
343 * If event was in error state, then keep it
344 * that way, otherwise bogus counts will be
345 * returned on read(). The only way to get out
346 * of error state is by explicit re-enabling
347 * of the event
348 */
349 if (event->state > PERF_EVENT_STATE_OFF)
350 event->state = PERF_EVENT_STATE_OFF;
351
294 /* 352 /*
295 * If this was a group event with sibling events then 353 * If this was a group event with sibling events then
296 * upgrade the siblings to singleton events by adding them 354 * upgrade the siblings to singleton events by adding them
@@ -444,50 +502,11 @@ retry:
444 * can remove the event safely, if the call above did not 502 * can remove the event safely, if the call above did not
445 * succeed. 503 * succeed.
446 */ 504 */
447 if (!list_empty(&event->group_entry)) { 505 if (!list_empty(&event->group_entry))
448 list_del_event(event, ctx); 506 list_del_event(event, ctx);
449 }
450 spin_unlock_irq(&ctx->lock); 507 spin_unlock_irq(&ctx->lock);
451} 508}
452 509
453static inline u64 perf_clock(void)
454{
455 return cpu_clock(smp_processor_id());
456}
457
458/*
459 * Update the record of the current time in a context.
460 */
461static void update_context_time(struct perf_event_context *ctx)
462{
463 u64 now = perf_clock();
464
465 ctx->time += now - ctx->timestamp;
466 ctx->timestamp = now;
467}
468
469/*
470 * Update the total_time_enabled and total_time_running fields for a event.
471 */
472static void update_event_times(struct perf_event *event)
473{
474 struct perf_event_context *ctx = event->ctx;
475 u64 run_end;
476
477 if (event->state < PERF_EVENT_STATE_INACTIVE ||
478 event->group_leader->state < PERF_EVENT_STATE_INACTIVE)
479 return;
480
481 event->total_time_enabled = ctx->time - event->tstamp_enabled;
482
483 if (event->state == PERF_EVENT_STATE_INACTIVE)
484 run_end = event->tstamp_stopped;
485 else
486 run_end = ctx->time;
487
488 event->total_time_running = run_end - event->tstamp_running;
489}
490
491/* 510/*
492 * Update total_time_enabled and total_time_running for all events in a group. 511 * Update total_time_enabled and total_time_running for all events in a group.
493 */ 512 */
@@ -1031,12 +1050,8 @@ void __perf_event_sched_out(struct perf_event_context *ctx,
1031 1050
1032 perf_disable(); 1051 perf_disable();
1033 if (ctx->nr_active) { 1052 if (ctx->nr_active) {
1034 list_for_each_entry(event, &ctx->group_list, group_entry) { 1053 list_for_each_entry(event, &ctx->group_list, group_entry)
1035 if (event != event->group_leader) 1054 group_sched_out(event, cpuctx, ctx);
1036 event_sched_out(event, cpuctx, ctx);
1037 else
1038 group_sched_out(event, cpuctx, ctx);
1039 }
1040 } 1055 }
1041 perf_enable(); 1056 perf_enable();
1042 out: 1057 out:
@@ -1062,8 +1077,6 @@ static int context_equiv(struct perf_event_context *ctx1,
1062 && !ctx1->pin_count && !ctx2->pin_count; 1077 && !ctx1->pin_count && !ctx2->pin_count;
1063} 1078}
1064 1079
1065static void __perf_event_read(void *event);
1066
1067static void __perf_event_sync_stat(struct perf_event *event, 1080static void __perf_event_sync_stat(struct perf_event *event,
1068 struct perf_event *next_event) 1081 struct perf_event *next_event)
1069{ 1082{
@@ -1081,8 +1094,8 @@ static void __perf_event_sync_stat(struct perf_event *event,
1081 */ 1094 */
1082 switch (event->state) { 1095 switch (event->state) {
1083 case PERF_EVENT_STATE_ACTIVE: 1096 case PERF_EVENT_STATE_ACTIVE:
1084 __perf_event_read(event); 1097 event->pmu->read(event);
1085 break; 1098 /* fall-through */
1086 1099
1087 case PERF_EVENT_STATE_INACTIVE: 1100 case PERF_EVENT_STATE_INACTIVE:
1088 update_event_times(event); 1101 update_event_times(event);
@@ -1121,6 +1134,8 @@ static void perf_event_sync_stat(struct perf_event_context *ctx,
1121 if (!ctx->nr_stat) 1134 if (!ctx->nr_stat)
1122 return; 1135 return;
1123 1136
1137 update_context_time(ctx);
1138
1124 event = list_first_entry(&ctx->event_list, 1139 event = list_first_entry(&ctx->event_list,
1125 struct perf_event, event_entry); 1140 struct perf_event, event_entry);
1126 1141
@@ -1164,8 +1179,6 @@ void perf_event_task_sched_out(struct task_struct *task,
1164 if (likely(!ctx || !cpuctx->task_ctx)) 1179 if (likely(!ctx || !cpuctx->task_ctx))
1165 return; 1180 return;
1166 1181
1167 update_context_time(ctx);
1168
1169 rcu_read_lock(); 1182 rcu_read_lock();
1170 parent = rcu_dereference(ctx->parent_ctx); 1183 parent = rcu_dereference(ctx->parent_ctx);
1171 next_ctx = next->perf_event_ctxp; 1184 next_ctx = next->perf_event_ctxp;
@@ -1258,12 +1271,8 @@ __perf_event_sched_in(struct perf_event_context *ctx,
1258 if (event->cpu != -1 && event->cpu != cpu) 1271 if (event->cpu != -1 && event->cpu != cpu)
1259 continue; 1272 continue;
1260 1273
1261 if (event != event->group_leader) 1274 if (group_can_go_on(event, cpuctx, 1))
1262 event_sched_in(event, cpuctx, ctx, cpu); 1275 group_sched_in(event, cpuctx, ctx, cpu);
1263 else {
1264 if (group_can_go_on(event, cpuctx, 1))
1265 group_sched_in(event, cpuctx, ctx, cpu);
1266 }
1267 1276
1268 /* 1277 /*
1269 * If this pinned group hasn't been scheduled, 1278 * If this pinned group hasn't been scheduled,
@@ -1291,15 +1300,9 @@ __perf_event_sched_in(struct perf_event_context *ctx,
1291 if (event->cpu != -1 && event->cpu != cpu) 1300 if (event->cpu != -1 && event->cpu != cpu)
1292 continue; 1301 continue;
1293 1302
1294 if (event != event->group_leader) { 1303 if (group_can_go_on(event, cpuctx, can_add_hw))
1295 if (event_sched_in(event, cpuctx, ctx, cpu)) 1304 if (group_sched_in(event, cpuctx, ctx, cpu))
1296 can_add_hw = 0; 1305 can_add_hw = 0;
1297 } else {
1298 if (group_can_go_on(event, cpuctx, can_add_hw)) {
1299 if (group_sched_in(event, cpuctx, ctx, cpu))
1300 can_add_hw = 0;
1301 }
1302 }
1303 } 1306 }
1304 perf_enable(); 1307 perf_enable();
1305 out: 1308 out:
@@ -1368,7 +1371,7 @@ static void perf_ctx_adjust_freq(struct perf_event_context *ctx)
1368 u64 interrupts, freq; 1371 u64 interrupts, freq;
1369 1372
1370 spin_lock(&ctx->lock); 1373 spin_lock(&ctx->lock);
1371 list_for_each_entry(event, &ctx->group_list, group_entry) { 1374 list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
1372 if (event->state != PERF_EVENT_STATE_ACTIVE) 1375 if (event->state != PERF_EVENT_STATE_ACTIVE)
1373 continue; 1376 continue;
1374 1377
@@ -1528,7 +1531,6 @@ static void __perf_event_read(void *info)
1528 struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context); 1531 struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
1529 struct perf_event *event = info; 1532 struct perf_event *event = info;
1530 struct perf_event_context *ctx = event->ctx; 1533 struct perf_event_context *ctx = event->ctx;
1531 unsigned long flags;
1532 1534
1533 /* 1535 /*
1534 * If this is a task context, we need to check whether it is 1536 * If this is a task context, we need to check whether it is
@@ -1540,12 +1542,12 @@ static void __perf_event_read(void *info)
1540 if (ctx->task && cpuctx->task_ctx != ctx) 1542 if (ctx->task && cpuctx->task_ctx != ctx)
1541 return; 1543 return;
1542 1544
1543 local_irq_save(flags); 1545 spin_lock(&ctx->lock);
1544 if (ctx->is_active) 1546 update_context_time(ctx);
1545 update_context_time(ctx);
1546 event->pmu->read(event);
1547 update_event_times(event); 1547 update_event_times(event);
1548 local_irq_restore(flags); 1548 spin_unlock(&ctx->lock);
1549
1550 event->pmu->read(event);
1549} 1551}
1550 1552
1551static u64 perf_event_read(struct perf_event *event) 1553static u64 perf_event_read(struct perf_event *event)
@@ -1558,7 +1560,13 @@ static u64 perf_event_read(struct perf_event *event)
1558 smp_call_function_single(event->oncpu, 1560 smp_call_function_single(event->oncpu,
1559 __perf_event_read, event, 1); 1561 __perf_event_read, event, 1);
1560 } else if (event->state == PERF_EVENT_STATE_INACTIVE) { 1562 } else if (event->state == PERF_EVENT_STATE_INACTIVE) {
1563 struct perf_event_context *ctx = event->ctx;
1564 unsigned long flags;
1565
1566 spin_lock_irqsave(&ctx->lock, flags);
1567 update_context_time(ctx);
1561 update_event_times(event); 1568 update_event_times(event);
1569 spin_unlock_irqrestore(&ctx->lock, flags);
1562 } 1570 }
1563 1571
1564 return atomic64_read(&event->count); 1572 return atomic64_read(&event->count);
@@ -1671,6 +1679,8 @@ static struct perf_event_context *find_get_context(pid_t pid, int cpu)
1671 return ERR_PTR(err); 1679 return ERR_PTR(err);
1672} 1680}
1673 1681
1682static void perf_event_free_filter(struct perf_event *event);
1683
1674static void free_event_rcu(struct rcu_head *head) 1684static void free_event_rcu(struct rcu_head *head)
1675{ 1685{
1676 struct perf_event *event; 1686 struct perf_event *event;
@@ -1678,6 +1688,7 @@ static void free_event_rcu(struct rcu_head *head)
1678 event = container_of(head, struct perf_event, rcu_head); 1688 event = container_of(head, struct perf_event, rcu_head);
1679 if (event->ns) 1689 if (event->ns)
1680 put_pid_ns(event->ns); 1690 put_pid_ns(event->ns);
1691 perf_event_free_filter(event);
1681 kfree(event); 1692 kfree(event);
1682} 1693}
1683 1694
@@ -1709,16 +1720,10 @@ static void free_event(struct perf_event *event)
1709 call_rcu(&event->rcu_head, free_event_rcu); 1720 call_rcu(&event->rcu_head, free_event_rcu);
1710} 1721}
1711 1722
1712/* 1723int perf_event_release_kernel(struct perf_event *event)
1713 * Called when the last reference to the file is gone.
1714 */
1715static int perf_release(struct inode *inode, struct file *file)
1716{ 1724{
1717 struct perf_event *event = file->private_data;
1718 struct perf_event_context *ctx = event->ctx; 1725 struct perf_event_context *ctx = event->ctx;
1719 1726
1720 file->private_data = NULL;
1721
1722 WARN_ON_ONCE(ctx->parent_ctx); 1727 WARN_ON_ONCE(ctx->parent_ctx);
1723 mutex_lock(&ctx->mutex); 1728 mutex_lock(&ctx->mutex);
1724 perf_event_remove_from_context(event); 1729 perf_event_remove_from_context(event);
@@ -1733,6 +1738,19 @@ static int perf_release(struct inode *inode, struct file *file)
1733 1738
1734 return 0; 1739 return 0;
1735} 1740}
1741EXPORT_SYMBOL_GPL(perf_event_release_kernel);
1742
1743/*
1744 * Called when the last reference to the file is gone.
1745 */
1746static int perf_release(struct inode *inode, struct file *file)
1747{
1748 struct perf_event *event = file->private_data;
1749
1750 file->private_data = NULL;
1751
1752 return perf_event_release_kernel(event);
1753}
1736 1754
1737static int perf_event_read_size(struct perf_event *event) 1755static int perf_event_read_size(struct perf_event *event)
1738{ 1756{
@@ -1759,91 +1777,94 @@ static int perf_event_read_size(struct perf_event *event)
1759 return size; 1777 return size;
1760} 1778}
1761 1779
1762static u64 perf_event_read_value(struct perf_event *event) 1780u64 perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running)
1763{ 1781{
1764 struct perf_event *child; 1782 struct perf_event *child;
1765 u64 total = 0; 1783 u64 total = 0;
1766 1784
1785 *enabled = 0;
1786 *running = 0;
1787
1788 mutex_lock(&event->child_mutex);
1767 total += perf_event_read(event); 1789 total += perf_event_read(event);
1768 list_for_each_entry(child, &event->child_list, child_list) 1790 *enabled += event->total_time_enabled +
1791 atomic64_read(&event->child_total_time_enabled);
1792 *running += event->total_time_running +
1793 atomic64_read(&event->child_total_time_running);
1794
1795 list_for_each_entry(child, &event->child_list, child_list) {
1769 total += perf_event_read(child); 1796 total += perf_event_read(child);
1797 *enabled += child->total_time_enabled;
1798 *running += child->total_time_running;
1799 }
1800 mutex_unlock(&event->child_mutex);
1770 1801
1771 return total; 1802 return total;
1772} 1803}
1773 1804EXPORT_SYMBOL_GPL(perf_event_read_value);
1774static int perf_event_read_entry(struct perf_event *event,
1775 u64 read_format, char __user *buf)
1776{
1777 int n = 0, count = 0;
1778 u64 values[2];
1779
1780 values[n++] = perf_event_read_value(event);
1781 if (read_format & PERF_FORMAT_ID)
1782 values[n++] = primary_event_id(event);
1783
1784 count = n * sizeof(u64);
1785
1786 if (copy_to_user(buf, values, count))
1787 return -EFAULT;
1788
1789 return count;
1790}
1791 1805
1792static int perf_event_read_group(struct perf_event *event, 1806static int perf_event_read_group(struct perf_event *event,
1793 u64 read_format, char __user *buf) 1807 u64 read_format, char __user *buf)
1794{ 1808{
1795 struct perf_event *leader = event->group_leader, *sub; 1809 struct perf_event *leader = event->group_leader, *sub;
1796 int n = 0, size = 0, err = -EFAULT; 1810 int n = 0, size = 0, ret = -EFAULT;
1797 u64 values[3]; 1811 struct perf_event_context *ctx = leader->ctx;
1812 u64 values[5];
1813 u64 count, enabled, running;
1814
1815 mutex_lock(&ctx->mutex);
1816 count = perf_event_read_value(leader, &enabled, &running);
1798 1817
1799 values[n++] = 1 + leader->nr_siblings; 1818 values[n++] = 1 + leader->nr_siblings;
1800 if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { 1819 if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
1801 values[n++] = leader->total_time_enabled + 1820 values[n++] = enabled;
1802 atomic64_read(&leader->child_total_time_enabled); 1821 if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
1803 } 1822 values[n++] = running;
1804 if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { 1823 values[n++] = count;
1805 values[n++] = leader->total_time_running + 1824 if (read_format & PERF_FORMAT_ID)
1806 atomic64_read(&leader->child_total_time_running); 1825 values[n++] = primary_event_id(leader);
1807 }
1808 1826
1809 size = n * sizeof(u64); 1827 size = n * sizeof(u64);
1810 1828
1811 if (copy_to_user(buf, values, size)) 1829 if (copy_to_user(buf, values, size))
1812 return -EFAULT; 1830 goto unlock;
1813
1814 err = perf_event_read_entry(leader, read_format, buf + size);
1815 if (err < 0)
1816 return err;
1817 1831
1818 size += err; 1832 ret = size;
1819 1833
1820 list_for_each_entry(sub, &leader->sibling_list, group_entry) { 1834 list_for_each_entry(sub, &leader->sibling_list, group_entry) {
1821 err = perf_event_read_entry(sub, read_format, 1835 n = 0;
1822 buf + size); 1836
1823 if (err < 0) 1837 values[n++] = perf_event_read_value(sub, &enabled, &running);
1824 return err; 1838 if (read_format & PERF_FORMAT_ID)
1839 values[n++] = primary_event_id(sub);
1840
1841 size = n * sizeof(u64);
1842
1843 if (copy_to_user(buf + ret, values, size)) {
1844 ret = -EFAULT;
1845 goto unlock;
1846 }
1825 1847
1826 size += err; 1848 ret += size;
1827 } 1849 }
1850unlock:
1851 mutex_unlock(&ctx->mutex);
1828 1852
1829 return size; 1853 return ret;
1830} 1854}
1831 1855
1832static int perf_event_read_one(struct perf_event *event, 1856static int perf_event_read_one(struct perf_event *event,
1833 u64 read_format, char __user *buf) 1857 u64 read_format, char __user *buf)
1834{ 1858{
1859 u64 enabled, running;
1835 u64 values[4]; 1860 u64 values[4];
1836 int n = 0; 1861 int n = 0;
1837 1862
1838 values[n++] = perf_event_read_value(event); 1863 values[n++] = perf_event_read_value(event, &enabled, &running);
1839 if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { 1864 if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
1840 values[n++] = event->total_time_enabled + 1865 values[n++] = enabled;
1841 atomic64_read(&event->child_total_time_enabled); 1866 if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
1842 } 1867 values[n++] = running;
1843 if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
1844 values[n++] = event->total_time_running +
1845 atomic64_read(&event->child_total_time_running);
1846 }
1847 if (read_format & PERF_FORMAT_ID) 1868 if (read_format & PERF_FORMAT_ID)
1848 values[n++] = primary_event_id(event); 1869 values[n++] = primary_event_id(event);
1849 1870
@@ -1874,12 +1895,10 @@ perf_read_hw(struct perf_event *event, char __user *buf, size_t count)
1874 return -ENOSPC; 1895 return -ENOSPC;
1875 1896
1876 WARN_ON_ONCE(event->ctx->parent_ctx); 1897 WARN_ON_ONCE(event->ctx->parent_ctx);
1877 mutex_lock(&event->child_mutex);
1878 if (read_format & PERF_FORMAT_GROUP) 1898 if (read_format & PERF_FORMAT_GROUP)
1879 ret = perf_event_read_group(event, read_format, buf); 1899 ret = perf_event_read_group(event, read_format, buf);
1880 else 1900 else
1881 ret = perf_event_read_one(event, read_format, buf); 1901 ret = perf_event_read_one(event, read_format, buf);
1882 mutex_unlock(&event->child_mutex);
1883 1902
1884 return ret; 1903 return ret;
1885} 1904}
@@ -1987,7 +2006,8 @@ unlock:
1987 return ret; 2006 return ret;
1988} 2007}
1989 2008
1990int perf_event_set_output(struct perf_event *event, int output_fd); 2009static int perf_event_set_output(struct perf_event *event, int output_fd);
2010static int perf_event_set_filter(struct perf_event *event, void __user *arg);
1991 2011
1992static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 2012static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1993{ 2013{
@@ -2015,6 +2035,9 @@ static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
2015 case PERF_EVENT_IOC_SET_OUTPUT: 2035 case PERF_EVENT_IOC_SET_OUTPUT:
2016 return perf_event_set_output(event, arg); 2036 return perf_event_set_output(event, arg);
2017 2037
2038 case PERF_EVENT_IOC_SET_FILTER:
2039 return perf_event_set_filter(event, (void __user *)arg);
2040
2018 default: 2041 default:
2019 return -ENOTTY; 2042 return -ENOTTY;
2020 } 2043 }
@@ -2105,49 +2128,31 @@ unlock:
2105 rcu_read_unlock(); 2128 rcu_read_unlock();
2106} 2129}
2107 2130
2108static int perf_mmap_fault(struct vm_area_struct *vma, struct vm_fault *vmf) 2131static unsigned long perf_data_size(struct perf_mmap_data *data)
2109{ 2132{
2110 struct perf_event *event = vma->vm_file->private_data; 2133 return data->nr_pages << (PAGE_SHIFT + data->data_order);
2111 struct perf_mmap_data *data; 2134}
2112 int ret = VM_FAULT_SIGBUS;
2113
2114 if (vmf->flags & FAULT_FLAG_MKWRITE) {
2115 if (vmf->pgoff == 0)
2116 ret = 0;
2117 return ret;
2118 }
2119
2120 rcu_read_lock();
2121 data = rcu_dereference(event->data);
2122 if (!data)
2123 goto unlock;
2124
2125 if (vmf->pgoff == 0) {
2126 vmf->page = virt_to_page(data->user_page);
2127 } else {
2128 int nr = vmf->pgoff - 1;
2129
2130 if ((unsigned)nr > data->nr_pages)
2131 goto unlock;
2132 2135
2133 if (vmf->flags & FAULT_FLAG_WRITE) 2136#ifndef CONFIG_PERF_USE_VMALLOC
2134 goto unlock;
2135 2137
2136 vmf->page = virt_to_page(data->data_pages[nr]); 2138/*
2137 } 2139 * Back perf_mmap() with regular GFP_KERNEL-0 pages.
2140 */
2138 2141
2139 get_page(vmf->page); 2142static struct page *
2140 vmf->page->mapping = vma->vm_file->f_mapping; 2143perf_mmap_to_page(struct perf_mmap_data *data, unsigned long pgoff)
2141 vmf->page->index = vmf->pgoff; 2144{
2145 if (pgoff > data->nr_pages)
2146 return NULL;
2142 2147
2143 ret = 0; 2148 if (pgoff == 0)
2144unlock: 2149 return virt_to_page(data->user_page);
2145 rcu_read_unlock();
2146 2150
2147 return ret; 2151 return virt_to_page(data->data_pages[pgoff - 1]);
2148} 2152}
2149 2153
2150static int perf_mmap_data_alloc(struct perf_event *event, int nr_pages) 2154static struct perf_mmap_data *
2155perf_mmap_data_alloc(struct perf_event *event, int nr_pages)
2151{ 2156{
2152 struct perf_mmap_data *data; 2157 struct perf_mmap_data *data;
2153 unsigned long size; 2158 unsigned long size;
@@ -2172,19 +2177,10 @@ static int perf_mmap_data_alloc(struct perf_event *event, int nr_pages)
2172 goto fail_data_pages; 2177 goto fail_data_pages;
2173 } 2178 }
2174 2179
2180 data->data_order = 0;
2175 data->nr_pages = nr_pages; 2181 data->nr_pages = nr_pages;
2176 atomic_set(&data->lock, -1);
2177 2182
2178 if (event->attr.watermark) { 2183 return data;
2179 data->watermark = min_t(long, PAGE_SIZE * nr_pages,
2180 event->attr.wakeup_watermark);
2181 }
2182 if (!data->watermark)
2183 data->watermark = max(PAGE_SIZE, PAGE_SIZE * nr_pages / 4);
2184
2185 rcu_assign_pointer(event->data, data);
2186
2187 return 0;
2188 2184
2189fail_data_pages: 2185fail_data_pages:
2190 for (i--; i >= 0; i--) 2186 for (i--; i >= 0; i--)
@@ -2196,7 +2192,7 @@ fail_user_page:
2196 kfree(data); 2192 kfree(data);
2197 2193
2198fail: 2194fail:
2199 return -ENOMEM; 2195 return NULL;
2200} 2196}
2201 2197
2202static void perf_mmap_free_page(unsigned long addr) 2198static void perf_mmap_free_page(unsigned long addr)
@@ -2207,28 +2203,170 @@ static void perf_mmap_free_page(unsigned long addr)
2207 __free_page(page); 2203 __free_page(page);
2208} 2204}
2209 2205
2210static void __perf_mmap_data_free(struct rcu_head *rcu_head) 2206static void perf_mmap_data_free(struct perf_mmap_data *data)
2211{ 2207{
2212 struct perf_mmap_data *data;
2213 int i; 2208 int i;
2214 2209
2215 data = container_of(rcu_head, struct perf_mmap_data, rcu_head);
2216
2217 perf_mmap_free_page((unsigned long)data->user_page); 2210 perf_mmap_free_page((unsigned long)data->user_page);
2218 for (i = 0; i < data->nr_pages; i++) 2211 for (i = 0; i < data->nr_pages; i++)
2219 perf_mmap_free_page((unsigned long)data->data_pages[i]); 2212 perf_mmap_free_page((unsigned long)data->data_pages[i]);
2213 kfree(data);
2214}
2215
2216#else
2217
2218/*
2219 * Back perf_mmap() with vmalloc memory.
2220 *
2221 * Required for architectures that have d-cache aliasing issues.
2222 */
2223
2224static struct page *
2225perf_mmap_to_page(struct perf_mmap_data *data, unsigned long pgoff)
2226{
2227 if (pgoff > (1UL << data->data_order))
2228 return NULL;
2229
2230 return vmalloc_to_page((void *)data->user_page + pgoff * PAGE_SIZE);
2231}
2232
2233static void perf_mmap_unmark_page(void *addr)
2234{
2235 struct page *page = vmalloc_to_page(addr);
2236
2237 page->mapping = NULL;
2238}
2239
2240static void perf_mmap_data_free_work(struct work_struct *work)
2241{
2242 struct perf_mmap_data *data;
2243 void *base;
2244 int i, nr;
2245
2246 data = container_of(work, struct perf_mmap_data, work);
2247 nr = 1 << data->data_order;
2248
2249 base = data->user_page;
2250 for (i = 0; i < nr + 1; i++)
2251 perf_mmap_unmark_page(base + (i * PAGE_SIZE));
2252
2253 vfree(base);
2254 kfree(data);
2255}
2256
2257static void perf_mmap_data_free(struct perf_mmap_data *data)
2258{
2259 schedule_work(&data->work);
2260}
2261
2262static struct perf_mmap_data *
2263perf_mmap_data_alloc(struct perf_event *event, int nr_pages)
2264{
2265 struct perf_mmap_data *data;
2266 unsigned long size;
2267 void *all_buf;
2268
2269 WARN_ON(atomic_read(&event->mmap_count));
2270
2271 size = sizeof(struct perf_mmap_data);
2272 size += sizeof(void *);
2273
2274 data = kzalloc(size, GFP_KERNEL);
2275 if (!data)
2276 goto fail;
2220 2277
2278 INIT_WORK(&data->work, perf_mmap_data_free_work);
2279
2280 all_buf = vmalloc_user((nr_pages + 1) * PAGE_SIZE);
2281 if (!all_buf)
2282 goto fail_all_buf;
2283
2284 data->user_page = all_buf;
2285 data->data_pages[0] = all_buf + PAGE_SIZE;
2286 data->data_order = ilog2(nr_pages);
2287 data->nr_pages = 1;
2288
2289 return data;
2290
2291fail_all_buf:
2221 kfree(data); 2292 kfree(data);
2293
2294fail:
2295 return NULL;
2296}
2297
2298#endif
2299
2300static int perf_mmap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
2301{
2302 struct perf_event *event = vma->vm_file->private_data;
2303 struct perf_mmap_data *data;
2304 int ret = VM_FAULT_SIGBUS;
2305
2306 if (vmf->flags & FAULT_FLAG_MKWRITE) {
2307 if (vmf->pgoff == 0)
2308 ret = 0;
2309 return ret;
2310 }
2311
2312 rcu_read_lock();
2313 data = rcu_dereference(event->data);
2314 if (!data)
2315 goto unlock;
2316
2317 if (vmf->pgoff && (vmf->flags & FAULT_FLAG_WRITE))
2318 goto unlock;
2319
2320 vmf->page = perf_mmap_to_page(data, vmf->pgoff);
2321 if (!vmf->page)
2322 goto unlock;
2323
2324 get_page(vmf->page);
2325 vmf->page->mapping = vma->vm_file->f_mapping;
2326 vmf->page->index = vmf->pgoff;
2327
2328 ret = 0;
2329unlock:
2330 rcu_read_unlock();
2331
2332 return ret;
2222} 2333}
2223 2334
2224static void perf_mmap_data_free(struct perf_event *event) 2335static void
2336perf_mmap_data_init(struct perf_event *event, struct perf_mmap_data *data)
2337{
2338 long max_size = perf_data_size(data);
2339
2340 atomic_set(&data->lock, -1);
2341
2342 if (event->attr.watermark) {
2343 data->watermark = min_t(long, max_size,
2344 event->attr.wakeup_watermark);
2345 }
2346
2347 if (!data->watermark)
2348 data->watermark = max_size / 2;
2349
2350
2351 rcu_assign_pointer(event->data, data);
2352}
2353
2354static void perf_mmap_data_free_rcu(struct rcu_head *rcu_head)
2355{
2356 struct perf_mmap_data *data;
2357
2358 data = container_of(rcu_head, struct perf_mmap_data, rcu_head);
2359 perf_mmap_data_free(data);
2360}
2361
2362static void perf_mmap_data_release(struct perf_event *event)
2225{ 2363{
2226 struct perf_mmap_data *data = event->data; 2364 struct perf_mmap_data *data = event->data;
2227 2365
2228 WARN_ON(atomic_read(&event->mmap_count)); 2366 WARN_ON(atomic_read(&event->mmap_count));
2229 2367
2230 rcu_assign_pointer(event->data, NULL); 2368 rcu_assign_pointer(event->data, NULL);
2231 call_rcu(&data->rcu_head, __perf_mmap_data_free); 2369 call_rcu(&data->rcu_head, perf_mmap_data_free_rcu);
2232} 2370}
2233 2371
2234static void perf_mmap_open(struct vm_area_struct *vma) 2372static void perf_mmap_open(struct vm_area_struct *vma)
@@ -2244,11 +2382,12 @@ static void perf_mmap_close(struct vm_area_struct *vma)
2244 2382
2245 WARN_ON_ONCE(event->ctx->parent_ctx); 2383 WARN_ON_ONCE(event->ctx->parent_ctx);
2246 if (atomic_dec_and_mutex_lock(&event->mmap_count, &event->mmap_mutex)) { 2384 if (atomic_dec_and_mutex_lock(&event->mmap_count, &event->mmap_mutex)) {
2385 unsigned long size = perf_data_size(event->data);
2247 struct user_struct *user = current_user(); 2386 struct user_struct *user = current_user();
2248 2387
2249 atomic_long_sub(event->data->nr_pages + 1, &user->locked_vm); 2388 atomic_long_sub((size >> PAGE_SHIFT) + 1, &user->locked_vm);
2250 vma->vm_mm->locked_vm -= event->data->nr_locked; 2389 vma->vm_mm->locked_vm -= event->data->nr_locked;
2251 perf_mmap_data_free(event); 2390 perf_mmap_data_release(event);
2252 mutex_unlock(&event->mmap_mutex); 2391 mutex_unlock(&event->mmap_mutex);
2253 } 2392 }
2254} 2393}
@@ -2266,6 +2405,7 @@ static int perf_mmap(struct file *file, struct vm_area_struct *vma)
2266 unsigned long user_locked, user_lock_limit; 2405 unsigned long user_locked, user_lock_limit;
2267 struct user_struct *user = current_user(); 2406 struct user_struct *user = current_user();
2268 unsigned long locked, lock_limit; 2407 unsigned long locked, lock_limit;
2408 struct perf_mmap_data *data;
2269 unsigned long vma_size; 2409 unsigned long vma_size;
2270 unsigned long nr_pages; 2410 unsigned long nr_pages;
2271 long user_extra, extra; 2411 long user_extra, extra;
@@ -2328,10 +2468,15 @@ static int perf_mmap(struct file *file, struct vm_area_struct *vma)
2328 } 2468 }
2329 2469
2330 WARN_ON(event->data); 2470 WARN_ON(event->data);
2331 ret = perf_mmap_data_alloc(event, nr_pages); 2471
2332 if (ret) 2472 data = perf_mmap_data_alloc(event, nr_pages);
2473 ret = -ENOMEM;
2474 if (!data)
2333 goto unlock; 2475 goto unlock;
2334 2476
2477 ret = 0;
2478 perf_mmap_data_init(event, data);
2479
2335 atomic_set(&event->mmap_count, 1); 2480 atomic_set(&event->mmap_count, 1);
2336 atomic_long_add(user_extra, &user->locked_vm); 2481 atomic_long_add(user_extra, &user->locked_vm);
2337 vma->vm_mm->locked_vm += extra; 2482 vma->vm_mm->locked_vm += extra;
@@ -2519,7 +2664,7 @@ static bool perf_output_space(struct perf_mmap_data *data, unsigned long tail,
2519 if (!data->writable) 2664 if (!data->writable)
2520 return true; 2665 return true;
2521 2666
2522 mask = (data->nr_pages << PAGE_SHIFT) - 1; 2667 mask = perf_data_size(data) - 1;
2523 2668
2524 offset = (offset - tail) & mask; 2669 offset = (offset - tail) & mask;
2525 head = (head - tail) & mask; 2670 head = (head - tail) & mask;
@@ -2558,20 +2703,21 @@ static void perf_output_wakeup(struct perf_output_handle *handle)
2558static void perf_output_lock(struct perf_output_handle *handle) 2703static void perf_output_lock(struct perf_output_handle *handle)
2559{ 2704{
2560 struct perf_mmap_data *data = handle->data; 2705 struct perf_mmap_data *data = handle->data;
2561 int cpu; 2706 int cur, cpu = get_cpu();
2562 2707
2563 handle->locked = 0; 2708 handle->locked = 0;
2564 2709
2565 local_irq_save(handle->flags); 2710 for (;;) {
2566 cpu = smp_processor_id(); 2711 cur = atomic_cmpxchg(&data->lock, -1, cpu);
2567 2712 if (cur == -1) {
2568 if (in_nmi() && atomic_read(&data->lock) == cpu) 2713 handle->locked = 1;
2569 return; 2714 break;
2715 }
2716 if (cur == cpu)
2717 break;
2570 2718
2571 while (atomic_cmpxchg(&data->lock, -1, cpu) != -1)
2572 cpu_relax(); 2719 cpu_relax();
2573 2720 }
2574 handle->locked = 1;
2575} 2721}
2576 2722
2577static void perf_output_unlock(struct perf_output_handle *handle) 2723static void perf_output_unlock(struct perf_output_handle *handle)
@@ -2617,14 +2763,14 @@ again:
2617 if (atomic_xchg(&data->wakeup, 0)) 2763 if (atomic_xchg(&data->wakeup, 0))
2618 perf_output_wakeup(handle); 2764 perf_output_wakeup(handle);
2619out: 2765out:
2620 local_irq_restore(handle->flags); 2766 put_cpu();
2621} 2767}
2622 2768
2623void perf_output_copy(struct perf_output_handle *handle, 2769void perf_output_copy(struct perf_output_handle *handle,
2624 const void *buf, unsigned int len) 2770 const void *buf, unsigned int len)
2625{ 2771{
2626 unsigned int pages_mask; 2772 unsigned int pages_mask;
2627 unsigned int offset; 2773 unsigned long offset;
2628 unsigned int size; 2774 unsigned int size;
2629 void **pages; 2775 void **pages;
2630 2776
@@ -2633,12 +2779,14 @@ void perf_output_copy(struct perf_output_handle *handle,
2633 pages = handle->data->data_pages; 2779 pages = handle->data->data_pages;
2634 2780
2635 do { 2781 do {
2636 unsigned int page_offset; 2782 unsigned long page_offset;
2783 unsigned long page_size;
2637 int nr; 2784 int nr;
2638 2785
2639 nr = (offset >> PAGE_SHIFT) & pages_mask; 2786 nr = (offset >> PAGE_SHIFT) & pages_mask;
2640 page_offset = offset & (PAGE_SIZE - 1); 2787 page_size = 1UL << (handle->data->data_order + PAGE_SHIFT);
2641 size = min_t(unsigned int, PAGE_SIZE - page_offset, len); 2788 page_offset = offset & (page_size - 1);
2789 size = min_t(unsigned int, page_size - page_offset, len);
2642 2790
2643 memcpy(pages[nr] + page_offset, buf, size); 2791 memcpy(pages[nr] + page_offset, buf, size);
2644 2792
@@ -3126,15 +3274,10 @@ static void perf_event_task_ctx(struct perf_event_context *ctx,
3126{ 3274{
3127 struct perf_event *event; 3275 struct perf_event *event;
3128 3276
3129 if (system_state != SYSTEM_RUNNING || list_empty(&ctx->event_list))
3130 return;
3131
3132 rcu_read_lock();
3133 list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { 3277 list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
3134 if (perf_event_task_match(event)) 3278 if (perf_event_task_match(event))
3135 perf_event_task_output(event, task_event); 3279 perf_event_task_output(event, task_event);
3136 } 3280 }
3137 rcu_read_unlock();
3138} 3281}
3139 3282
3140static void perf_event_task_event(struct perf_task_event *task_event) 3283static void perf_event_task_event(struct perf_task_event *task_event)
@@ -3142,11 +3285,11 @@ static void perf_event_task_event(struct perf_task_event *task_event)
3142 struct perf_cpu_context *cpuctx; 3285 struct perf_cpu_context *cpuctx;
3143 struct perf_event_context *ctx = task_event->task_ctx; 3286 struct perf_event_context *ctx = task_event->task_ctx;
3144 3287
3288 rcu_read_lock();
3145 cpuctx = &get_cpu_var(perf_cpu_context); 3289 cpuctx = &get_cpu_var(perf_cpu_context);
3146 perf_event_task_ctx(&cpuctx->ctx, task_event); 3290 perf_event_task_ctx(&cpuctx->ctx, task_event);
3147 put_cpu_var(perf_cpu_context); 3291 put_cpu_var(perf_cpu_context);
3148 3292
3149 rcu_read_lock();
3150 if (!ctx) 3293 if (!ctx)
3151 ctx = rcu_dereference(task_event->task->perf_event_ctxp); 3294 ctx = rcu_dereference(task_event->task->perf_event_ctxp);
3152 if (ctx) 3295 if (ctx)
@@ -3238,15 +3381,10 @@ static void perf_event_comm_ctx(struct perf_event_context *ctx,
3238{ 3381{
3239 struct perf_event *event; 3382 struct perf_event *event;
3240 3383
3241 if (system_state != SYSTEM_RUNNING || list_empty(&ctx->event_list))
3242 return;
3243
3244 rcu_read_lock();
3245 list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { 3384 list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
3246 if (perf_event_comm_match(event)) 3385 if (perf_event_comm_match(event))
3247 perf_event_comm_output(event, comm_event); 3386 perf_event_comm_output(event, comm_event);
3248 } 3387 }
3249 rcu_read_unlock();
3250} 3388}
3251 3389
3252static void perf_event_comm_event(struct perf_comm_event *comm_event) 3390static void perf_event_comm_event(struct perf_comm_event *comm_event)
@@ -3257,7 +3395,7 @@ static void perf_event_comm_event(struct perf_comm_event *comm_event)
3257 char comm[TASK_COMM_LEN]; 3395 char comm[TASK_COMM_LEN];
3258 3396
3259 memset(comm, 0, sizeof(comm)); 3397 memset(comm, 0, sizeof(comm));
3260 strncpy(comm, comm_event->task->comm, sizeof(comm)); 3398 strlcpy(comm, comm_event->task->comm, sizeof(comm));
3261 size = ALIGN(strlen(comm)+1, sizeof(u64)); 3399 size = ALIGN(strlen(comm)+1, sizeof(u64));
3262 3400
3263 comm_event->comm = comm; 3401 comm_event->comm = comm;
@@ -3265,11 +3403,11 @@ static void perf_event_comm_event(struct perf_comm_event *comm_event)
3265 3403
3266 comm_event->event_id.header.size = sizeof(comm_event->event_id) + size; 3404 comm_event->event_id.header.size = sizeof(comm_event->event_id) + size;
3267 3405
3406 rcu_read_lock();
3268 cpuctx = &get_cpu_var(perf_cpu_context); 3407 cpuctx = &get_cpu_var(perf_cpu_context);
3269 perf_event_comm_ctx(&cpuctx->ctx, comm_event); 3408 perf_event_comm_ctx(&cpuctx->ctx, comm_event);
3270 put_cpu_var(perf_cpu_context); 3409 put_cpu_var(perf_cpu_context);
3271 3410
3272 rcu_read_lock();
3273 /* 3411 /*
3274 * doesn't really matter which of the child contexts the 3412 * doesn't really matter which of the child contexts the
3275 * events ends up in. 3413 * events ends up in.
@@ -3362,15 +3500,10 @@ static void perf_event_mmap_ctx(struct perf_event_context *ctx,
3362{ 3500{
3363 struct perf_event *event; 3501 struct perf_event *event;
3364 3502
3365 if (system_state != SYSTEM_RUNNING || list_empty(&ctx->event_list))
3366 return;
3367
3368 rcu_read_lock();
3369 list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { 3503 list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
3370 if (perf_event_mmap_match(event, mmap_event)) 3504 if (perf_event_mmap_match(event, mmap_event))
3371 perf_event_mmap_output(event, mmap_event); 3505 perf_event_mmap_output(event, mmap_event);
3372 } 3506 }
3373 rcu_read_unlock();
3374} 3507}
3375 3508
3376static void perf_event_mmap_event(struct perf_mmap_event *mmap_event) 3509static void perf_event_mmap_event(struct perf_mmap_event *mmap_event)
@@ -3426,11 +3559,11 @@ got_name:
3426 3559
3427 mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size; 3560 mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size;
3428 3561
3562 rcu_read_lock();
3429 cpuctx = &get_cpu_var(perf_cpu_context); 3563 cpuctx = &get_cpu_var(perf_cpu_context);
3430 perf_event_mmap_ctx(&cpuctx->ctx, mmap_event); 3564 perf_event_mmap_ctx(&cpuctx->ctx, mmap_event);
3431 put_cpu_var(perf_cpu_context); 3565 put_cpu_var(perf_cpu_context);
3432 3566
3433 rcu_read_lock();
3434 /* 3567 /*
3435 * doesn't really matter which of the child contexts the 3568 * doesn't really matter which of the child contexts the
3436 * events ends up in. 3569 * events ends up in.
@@ -3569,7 +3702,11 @@ static int __perf_event_overflow(struct perf_event *event, int nmi,
3569 perf_event_disable(event); 3702 perf_event_disable(event);
3570 } 3703 }
3571 3704
3572 perf_event_output(event, nmi, data, regs); 3705 if (event->overflow_handler)
3706 event->overflow_handler(event, nmi, data, regs);
3707 else
3708 perf_event_output(event, nmi, data, regs);
3709
3573 return ret; 3710 return ret;
3574} 3711}
3575 3712
@@ -3614,16 +3751,16 @@ again:
3614 return nr; 3751 return nr;
3615} 3752}
3616 3753
3617static void perf_swevent_overflow(struct perf_event *event, 3754static void perf_swevent_overflow(struct perf_event *event, u64 overflow,
3618 int nmi, struct perf_sample_data *data, 3755 int nmi, struct perf_sample_data *data,
3619 struct pt_regs *regs) 3756 struct pt_regs *regs)
3620{ 3757{
3621 struct hw_perf_event *hwc = &event->hw; 3758 struct hw_perf_event *hwc = &event->hw;
3622 int throttle = 0; 3759 int throttle = 0;
3623 u64 overflow;
3624 3760
3625 data->period = event->hw.last_period; 3761 data->period = event->hw.last_period;
3626 overflow = perf_swevent_set_period(event); 3762 if (!overflow)
3763 overflow = perf_swevent_set_period(event);
3627 3764
3628 if (hwc->interrupts == MAX_INTERRUPTS) 3765 if (hwc->interrupts == MAX_INTERRUPTS)
3629 return; 3766 return;
@@ -3656,14 +3793,19 @@ static void perf_swevent_add(struct perf_event *event, u64 nr,
3656 3793
3657 atomic64_add(nr, &event->count); 3794 atomic64_add(nr, &event->count);
3658 3795
3796 if (!regs)
3797 return;
3798
3659 if (!hwc->sample_period) 3799 if (!hwc->sample_period)
3660 return; 3800 return;
3661 3801
3662 if (!regs) 3802 if (nr == 1 && hwc->sample_period == 1 && !event->attr.freq)
3803 return perf_swevent_overflow(event, 1, nmi, data, regs);
3804
3805 if (atomic64_add_negative(nr, &hwc->period_left))
3663 return; 3806 return;
3664 3807
3665 if (!atomic64_add_negative(nr, &hwc->period_left)) 3808 perf_swevent_overflow(event, 0, nmi, data, regs);
3666 perf_swevent_overflow(event, nmi, data, regs);
3667} 3809}
3668 3810
3669static int perf_swevent_is_counting(struct perf_event *event) 3811static int perf_swevent_is_counting(struct perf_event *event)
@@ -3696,25 +3838,44 @@ static int perf_swevent_is_counting(struct perf_event *event)
3696 return 1; 3838 return 1;
3697} 3839}
3698 3840
3841static int perf_tp_event_match(struct perf_event *event,
3842 struct perf_sample_data *data);
3843
3844static int perf_exclude_event(struct perf_event *event,
3845 struct pt_regs *regs)
3846{
3847 if (regs) {
3848 if (event->attr.exclude_user && user_mode(regs))
3849 return 1;
3850
3851 if (event->attr.exclude_kernel && !user_mode(regs))
3852 return 1;
3853 }
3854
3855 return 0;
3856}
3857
3699static int perf_swevent_match(struct perf_event *event, 3858static int perf_swevent_match(struct perf_event *event,
3700 enum perf_type_id type, 3859 enum perf_type_id type,
3701 u32 event_id, struct pt_regs *regs) 3860 u32 event_id,
3861 struct perf_sample_data *data,
3862 struct pt_regs *regs)
3702{ 3863{
3703 if (!perf_swevent_is_counting(event)) 3864 if (!perf_swevent_is_counting(event))
3704 return 0; 3865 return 0;
3705 3866
3706 if (event->attr.type != type) 3867 if (event->attr.type != type)
3707 return 0; 3868 return 0;
3869
3708 if (event->attr.config != event_id) 3870 if (event->attr.config != event_id)
3709 return 0; 3871 return 0;
3710 3872
3711 if (regs) { 3873 if (perf_exclude_event(event, regs))
3712 if (event->attr.exclude_user && user_mode(regs)) 3874 return 0;
3713 return 0;
3714 3875
3715 if (event->attr.exclude_kernel && !user_mode(regs)) 3876 if (event->attr.type == PERF_TYPE_TRACEPOINT &&
3716 return 0; 3877 !perf_tp_event_match(event, data))
3717 } 3878 return 0;
3718 3879
3719 return 1; 3880 return 1;
3720} 3881}
@@ -3727,49 +3888,59 @@ static void perf_swevent_ctx_event(struct perf_event_context *ctx,
3727{ 3888{
3728 struct perf_event *event; 3889 struct perf_event *event;
3729 3890
3730 if (system_state != SYSTEM_RUNNING || list_empty(&ctx->event_list))
3731 return;
3732
3733 rcu_read_lock();
3734 list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { 3891 list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
3735 if (perf_swevent_match(event, type, event_id, regs)) 3892 if (perf_swevent_match(event, type, event_id, data, regs))
3736 perf_swevent_add(event, nr, nmi, data, regs); 3893 perf_swevent_add(event, nr, nmi, data, regs);
3737 } 3894 }
3738 rcu_read_unlock();
3739} 3895}
3740 3896
3741static int *perf_swevent_recursion_context(struct perf_cpu_context *cpuctx) 3897int perf_swevent_get_recursion_context(void)
3742{ 3898{
3899 struct perf_cpu_context *cpuctx = &get_cpu_var(perf_cpu_context);
3900 int rctx;
3901
3743 if (in_nmi()) 3902 if (in_nmi())
3744 return &cpuctx->recursion[3]; 3903 rctx = 3;
3904 else if (in_irq())
3905 rctx = 2;
3906 else if (in_softirq())
3907 rctx = 1;
3908 else
3909 rctx = 0;
3745 3910
3746 if (in_irq()) 3911 if (cpuctx->recursion[rctx]) {
3747 return &cpuctx->recursion[2]; 3912 put_cpu_var(perf_cpu_context);
3913 return -1;
3914 }
3748 3915
3749 if (in_softirq()) 3916 cpuctx->recursion[rctx]++;
3750 return &cpuctx->recursion[1]; 3917 barrier();
3751 3918
3752 return &cpuctx->recursion[0]; 3919 return rctx;
3920}
3921EXPORT_SYMBOL_GPL(perf_swevent_get_recursion_context);
3922
3923void perf_swevent_put_recursion_context(int rctx)
3924{
3925 struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
3926 barrier();
3927 cpuctx->recursion[rctx]--;
3928 put_cpu_var(perf_cpu_context);
3753} 3929}
3930EXPORT_SYMBOL_GPL(perf_swevent_put_recursion_context);
3754 3931
3755static void do_perf_sw_event(enum perf_type_id type, u32 event_id, 3932static void do_perf_sw_event(enum perf_type_id type, u32 event_id,
3756 u64 nr, int nmi, 3933 u64 nr, int nmi,
3757 struct perf_sample_data *data, 3934 struct perf_sample_data *data,
3758 struct pt_regs *regs) 3935 struct pt_regs *regs)
3759{ 3936{
3760 struct perf_cpu_context *cpuctx = &get_cpu_var(perf_cpu_context); 3937 struct perf_cpu_context *cpuctx;
3761 int *recursion = perf_swevent_recursion_context(cpuctx);
3762 struct perf_event_context *ctx; 3938 struct perf_event_context *ctx;
3763 3939
3764 if (*recursion) 3940 cpuctx = &__get_cpu_var(perf_cpu_context);
3765 goto out; 3941 rcu_read_lock();
3766
3767 (*recursion)++;
3768 barrier();
3769
3770 perf_swevent_ctx_event(&cpuctx->ctx, type, event_id, 3942 perf_swevent_ctx_event(&cpuctx->ctx, type, event_id,
3771 nr, nmi, data, regs); 3943 nr, nmi, data, regs);
3772 rcu_read_lock();
3773 /* 3944 /*
3774 * doesn't really matter which of the child contexts the 3945 * doesn't really matter which of the child contexts the
3775 * events ends up in. 3946 * events ends up in.
@@ -3778,23 +3949,24 @@ static void do_perf_sw_event(enum perf_type_id type, u32 event_id,
3778 if (ctx) 3949 if (ctx)
3779 perf_swevent_ctx_event(ctx, type, event_id, nr, nmi, data, regs); 3950 perf_swevent_ctx_event(ctx, type, event_id, nr, nmi, data, regs);
3780 rcu_read_unlock(); 3951 rcu_read_unlock();
3781
3782 barrier();
3783 (*recursion)--;
3784
3785out:
3786 put_cpu_var(perf_cpu_context);
3787} 3952}
3788 3953
3789void __perf_sw_event(u32 event_id, u64 nr, int nmi, 3954void __perf_sw_event(u32 event_id, u64 nr, int nmi,
3790 struct pt_regs *regs, u64 addr) 3955 struct pt_regs *regs, u64 addr)
3791{ 3956{
3792 struct perf_sample_data data = { 3957 struct perf_sample_data data;
3793 .addr = addr, 3958 int rctx;
3794 };
3795 3959
3796 do_perf_sw_event(PERF_TYPE_SOFTWARE, event_id, nr, nmi, 3960 rctx = perf_swevent_get_recursion_context();
3797 &data, regs); 3961 if (rctx < 0)
3962 return;
3963
3964 data.addr = addr;
3965 data.raw = NULL;
3966
3967 do_perf_sw_event(PERF_TYPE_SOFTWARE, event_id, nr, nmi, &data, regs);
3968
3969 perf_swevent_put_recursion_context(rctx);
3798} 3970}
3799 3971
3800static void perf_swevent_read(struct perf_event *event) 3972static void perf_swevent_read(struct perf_event *event)
@@ -3839,6 +4011,7 @@ static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer)
3839 event->pmu->read(event); 4011 event->pmu->read(event);
3840 4012
3841 data.addr = 0; 4013 data.addr = 0;
4014 data.period = event->hw.last_period;
3842 regs = get_irq_regs(); 4015 regs = get_irq_regs();
3843 /* 4016 /*
3844 * In case we exclude kernel IPs or are somehow not in interrupt 4017 * In case we exclude kernel IPs or are somehow not in interrupt
@@ -3849,8 +4022,9 @@ static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer)
3849 regs = task_pt_regs(current); 4022 regs = task_pt_regs(current);
3850 4023
3851 if (regs) { 4024 if (regs) {
3852 if (perf_event_overflow(event, 0, &data, regs)) 4025 if (!(event->attr.exclude_idle && current->pid == 0))
3853 ret = HRTIMER_NORESTART; 4026 if (perf_event_overflow(event, 0, &data, regs))
4027 ret = HRTIMER_NORESTART;
3854 } 4028 }
3855 4029
3856 period = max_t(u64, 10000, event->hw.sample_period); 4030 period = max_t(u64, 10000, event->hw.sample_period);
@@ -3859,6 +4033,42 @@ static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer)
3859 return ret; 4033 return ret;
3860} 4034}
3861 4035
4036static void perf_swevent_start_hrtimer(struct perf_event *event)
4037{
4038 struct hw_perf_event *hwc = &event->hw;
4039
4040 hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
4041 hwc->hrtimer.function = perf_swevent_hrtimer;
4042 if (hwc->sample_period) {
4043 u64 period;
4044
4045 if (hwc->remaining) {
4046 if (hwc->remaining < 0)
4047 period = 10000;
4048 else
4049 period = hwc->remaining;
4050 hwc->remaining = 0;
4051 } else {
4052 period = max_t(u64, 10000, hwc->sample_period);
4053 }
4054 __hrtimer_start_range_ns(&hwc->hrtimer,
4055 ns_to_ktime(period), 0,
4056 HRTIMER_MODE_REL, 0);
4057 }
4058}
4059
4060static void perf_swevent_cancel_hrtimer(struct perf_event *event)
4061{
4062 struct hw_perf_event *hwc = &event->hw;
4063
4064 if (hwc->sample_period) {
4065 ktime_t remaining = hrtimer_get_remaining(&hwc->hrtimer);
4066 hwc->remaining = ktime_to_ns(remaining);
4067
4068 hrtimer_cancel(&hwc->hrtimer);
4069 }
4070}
4071
3862/* 4072/*
3863 * Software event: cpu wall time clock 4073 * Software event: cpu wall time clock
3864 */ 4074 */
@@ -3881,22 +4091,14 @@ static int cpu_clock_perf_event_enable(struct perf_event *event)
3881 int cpu = raw_smp_processor_id(); 4091 int cpu = raw_smp_processor_id();
3882 4092
3883 atomic64_set(&hwc->prev_count, cpu_clock(cpu)); 4093 atomic64_set(&hwc->prev_count, cpu_clock(cpu));
3884 hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); 4094 perf_swevent_start_hrtimer(event);
3885 hwc->hrtimer.function = perf_swevent_hrtimer;
3886 if (hwc->sample_period) {
3887 u64 period = max_t(u64, 10000, hwc->sample_period);
3888 __hrtimer_start_range_ns(&hwc->hrtimer,
3889 ns_to_ktime(period), 0,
3890 HRTIMER_MODE_REL, 0);
3891 }
3892 4095
3893 return 0; 4096 return 0;
3894} 4097}
3895 4098
3896static void cpu_clock_perf_event_disable(struct perf_event *event) 4099static void cpu_clock_perf_event_disable(struct perf_event *event)
3897{ 4100{
3898 if (event->hw.sample_period) 4101 perf_swevent_cancel_hrtimer(event);
3899 hrtimer_cancel(&event->hw.hrtimer);
3900 cpu_clock_perf_event_update(event); 4102 cpu_clock_perf_event_update(event);
3901} 4103}
3902 4104
@@ -3933,22 +4135,15 @@ static int task_clock_perf_event_enable(struct perf_event *event)
3933 now = event->ctx->time; 4135 now = event->ctx->time;
3934 4136
3935 atomic64_set(&hwc->prev_count, now); 4137 atomic64_set(&hwc->prev_count, now);
3936 hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); 4138
3937 hwc->hrtimer.function = perf_swevent_hrtimer; 4139 perf_swevent_start_hrtimer(event);
3938 if (hwc->sample_period) {
3939 u64 period = max_t(u64, 10000, hwc->sample_period);
3940 __hrtimer_start_range_ns(&hwc->hrtimer,
3941 ns_to_ktime(period), 0,
3942 HRTIMER_MODE_REL, 0);
3943 }
3944 4140
3945 return 0; 4141 return 0;
3946} 4142}
3947 4143
3948static void task_clock_perf_event_disable(struct perf_event *event) 4144static void task_clock_perf_event_disable(struct perf_event *event)
3949{ 4145{
3950 if (event->hw.sample_period) 4146 perf_swevent_cancel_hrtimer(event);
3951 hrtimer_cancel(&event->hw.hrtimer);
3952 task_clock_perf_event_update(event, event->ctx->time); 4147 task_clock_perf_event_update(event, event->ctx->time);
3953 4148
3954} 4149}
@@ -3976,6 +4171,7 @@ static const struct pmu perf_ops_task_clock = {
3976}; 4171};
3977 4172
3978#ifdef CONFIG_EVENT_PROFILE 4173#ifdef CONFIG_EVENT_PROFILE
4174
3979void perf_tp_event(int event_id, u64 addr, u64 count, void *record, 4175void perf_tp_event(int event_id, u64 addr, u64 count, void *record,
3980 int entry_size) 4176 int entry_size)
3981{ 4177{
@@ -3994,13 +4190,21 @@ void perf_tp_event(int event_id, u64 addr, u64 count, void *record,
3994 if (!regs) 4190 if (!regs)
3995 regs = task_pt_regs(current); 4191 regs = task_pt_regs(current);
3996 4192
4193 /* Trace events already protected against recursion */
3997 do_perf_sw_event(PERF_TYPE_TRACEPOINT, event_id, count, 1, 4194 do_perf_sw_event(PERF_TYPE_TRACEPOINT, event_id, count, 1,
3998 &data, regs); 4195 &data, regs);
3999} 4196}
4000EXPORT_SYMBOL_GPL(perf_tp_event); 4197EXPORT_SYMBOL_GPL(perf_tp_event);
4001 4198
4002extern int ftrace_profile_enable(int); 4199static int perf_tp_event_match(struct perf_event *event,
4003extern void ftrace_profile_disable(int); 4200 struct perf_sample_data *data)
4201{
4202 void *record = data->raw->data;
4203
4204 if (likely(!event->filter) || filter_match_preds(event->filter, record))
4205 return 1;
4206 return 0;
4207}
4004 4208
4005static void tp_perf_event_destroy(struct perf_event *event) 4209static void tp_perf_event_destroy(struct perf_event *event)
4006{ 4210{
@@ -4025,11 +4229,99 @@ static const struct pmu *tp_perf_event_init(struct perf_event *event)
4025 4229
4026 return &perf_ops_generic; 4230 return &perf_ops_generic;
4027} 4231}
4232
4233static int perf_event_set_filter(struct perf_event *event, void __user *arg)
4234{
4235 char *filter_str;
4236 int ret;
4237
4238 if (event->attr.type != PERF_TYPE_TRACEPOINT)
4239 return -EINVAL;
4240
4241 filter_str = strndup_user(arg, PAGE_SIZE);
4242 if (IS_ERR(filter_str))
4243 return PTR_ERR(filter_str);
4244
4245 ret = ftrace_profile_set_filter(event, event->attr.config, filter_str);
4246
4247 kfree(filter_str);
4248 return ret;
4249}
4250
4251static void perf_event_free_filter(struct perf_event *event)
4252{
4253 ftrace_profile_free_filter(event);
4254}
4255
4028#else 4256#else
4257
4258static int perf_tp_event_match(struct perf_event *event,
4259 struct perf_sample_data *data)
4260{
4261 return 1;
4262}
4263
4029static const struct pmu *tp_perf_event_init(struct perf_event *event) 4264static const struct pmu *tp_perf_event_init(struct perf_event *event)
4030{ 4265{
4031 return NULL; 4266 return NULL;
4032} 4267}
4268
4269static int perf_event_set_filter(struct perf_event *event, void __user *arg)
4270{
4271 return -ENOENT;
4272}
4273
4274static void perf_event_free_filter(struct perf_event *event)
4275{
4276}
4277
4278#endif /* CONFIG_EVENT_PROFILE */
4279
4280#ifdef CONFIG_HAVE_HW_BREAKPOINT
4281static void bp_perf_event_destroy(struct perf_event *event)
4282{
4283 release_bp_slot(event);
4284}
4285
4286static const struct pmu *bp_perf_event_init(struct perf_event *bp)
4287{
4288 int err;
4289 /*
4290 * The breakpoint is already filled if we haven't created the counter
4291 * through perf syscall
4292 * FIXME: manage to get trigerred to NULL if it comes from syscalls
4293 */
4294 if (!bp->callback)
4295 err = register_perf_hw_breakpoint(bp);
4296 else
4297 err = __register_perf_hw_breakpoint(bp);
4298 if (err)
4299 return ERR_PTR(err);
4300
4301 bp->destroy = bp_perf_event_destroy;
4302
4303 return &perf_ops_bp;
4304}
4305
4306void perf_bp_event(struct perf_event *bp, void *data)
4307{
4308 struct perf_sample_data sample;
4309 struct pt_regs *regs = data;
4310
4311 sample.addr = bp->attr.bp_addr;
4312
4313 if (!perf_exclude_event(bp, regs))
4314 perf_swevent_add(bp, 1, 1, &sample, regs);
4315}
4316#else
4317static const struct pmu *bp_perf_event_init(struct perf_event *bp)
4318{
4319 return NULL;
4320}
4321
4322void perf_bp_event(struct perf_event *bp, void *regs)
4323{
4324}
4033#endif 4325#endif
4034 4326
4035atomic_t perf_swevent_enabled[PERF_COUNT_SW_MAX]; 4327atomic_t perf_swevent_enabled[PERF_COUNT_SW_MAX];
@@ -4076,6 +4368,8 @@ static const struct pmu *sw_perf_event_init(struct perf_event *event)
4076 case PERF_COUNT_SW_PAGE_FAULTS_MAJ: 4368 case PERF_COUNT_SW_PAGE_FAULTS_MAJ:
4077 case PERF_COUNT_SW_CONTEXT_SWITCHES: 4369 case PERF_COUNT_SW_CONTEXT_SWITCHES:
4078 case PERF_COUNT_SW_CPU_MIGRATIONS: 4370 case PERF_COUNT_SW_CPU_MIGRATIONS:
4371 case PERF_COUNT_SW_ALIGNMENT_FAULTS:
4372 case PERF_COUNT_SW_EMULATION_FAULTS:
4079 if (!event->parent) { 4373 if (!event->parent) {
4080 atomic_inc(&perf_swevent_enabled[event_id]); 4374 atomic_inc(&perf_swevent_enabled[event_id]);
4081 event->destroy = sw_perf_event_destroy; 4375 event->destroy = sw_perf_event_destroy;
@@ -4096,6 +4390,7 @@ perf_event_alloc(struct perf_event_attr *attr,
4096 struct perf_event_context *ctx, 4390 struct perf_event_context *ctx,
4097 struct perf_event *group_leader, 4391 struct perf_event *group_leader,
4098 struct perf_event *parent_event, 4392 struct perf_event *parent_event,
4393 perf_callback_t callback,
4099 gfp_t gfpflags) 4394 gfp_t gfpflags)
4100{ 4395{
4101 const struct pmu *pmu; 4396 const struct pmu *pmu;
@@ -4138,6 +4433,11 @@ perf_event_alloc(struct perf_event_attr *attr,
4138 4433
4139 event->state = PERF_EVENT_STATE_INACTIVE; 4434 event->state = PERF_EVENT_STATE_INACTIVE;
4140 4435
4436 if (!callback && parent_event)
4437 callback = parent_event->callback;
4438
4439 event->callback = callback;
4440
4141 if (attr->disabled) 4441 if (attr->disabled)
4142 event->state = PERF_EVENT_STATE_OFF; 4442 event->state = PERF_EVENT_STATE_OFF;
4143 4443
@@ -4172,6 +4472,11 @@ perf_event_alloc(struct perf_event_attr *attr,
4172 pmu = tp_perf_event_init(event); 4472 pmu = tp_perf_event_init(event);
4173 break; 4473 break;
4174 4474
4475 case PERF_TYPE_BREAKPOINT:
4476 pmu = bp_perf_event_init(event);
4477 break;
4478
4479
4175 default: 4480 default:
4176 break; 4481 break;
4177 } 4482 }
@@ -4284,7 +4589,7 @@ err_size:
4284 goto out; 4589 goto out;
4285} 4590}
4286 4591
4287int perf_event_set_output(struct perf_event *event, int output_fd) 4592static int perf_event_set_output(struct perf_event *event, int output_fd)
4288{ 4593{
4289 struct perf_event *output_event = NULL; 4594 struct perf_event *output_event = NULL;
4290 struct file *output_file = NULL; 4595 struct file *output_file = NULL;
@@ -4414,7 +4719,7 @@ SYSCALL_DEFINE5(perf_event_open,
4414 } 4719 }
4415 4720
4416 event = perf_event_alloc(&attr, cpu, ctx, group_leader, 4721 event = perf_event_alloc(&attr, cpu, ctx, group_leader,
4417 NULL, GFP_KERNEL); 4722 NULL, NULL, GFP_KERNEL);
4418 err = PTR_ERR(event); 4723 err = PTR_ERR(event);
4419 if (IS_ERR(event)) 4724 if (IS_ERR(event))
4420 goto err_put_context; 4725 goto err_put_context;
@@ -4462,6 +4767,60 @@ err_put_context:
4462 return err; 4767 return err;
4463} 4768}
4464 4769
4770/**
4771 * perf_event_create_kernel_counter
4772 *
4773 * @attr: attributes of the counter to create
4774 * @cpu: cpu in which the counter is bound
4775 * @pid: task to profile
4776 */
4777struct perf_event *
4778perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu,
4779 pid_t pid, perf_callback_t callback)
4780{
4781 struct perf_event *event;
4782 struct perf_event_context *ctx;
4783 int err;
4784
4785 /*
4786 * Get the target context (task or percpu):
4787 */
4788
4789 ctx = find_get_context(pid, cpu);
4790 if (IS_ERR(ctx)) {
4791 err = PTR_ERR(ctx);
4792 goto err_exit;
4793 }
4794
4795 event = perf_event_alloc(attr, cpu, ctx, NULL,
4796 NULL, callback, GFP_KERNEL);
4797 if (IS_ERR(event)) {
4798 err = PTR_ERR(event);
4799 goto err_put_context;
4800 }
4801
4802 event->filp = NULL;
4803 WARN_ON_ONCE(ctx->parent_ctx);
4804 mutex_lock(&ctx->mutex);
4805 perf_install_in_context(ctx, event, cpu);
4806 ++ctx->generation;
4807 mutex_unlock(&ctx->mutex);
4808
4809 event->owner = current;
4810 get_task_struct(current);
4811 mutex_lock(&current->perf_event_mutex);
4812 list_add_tail(&event->owner_entry, &current->perf_event_list);
4813 mutex_unlock(&current->perf_event_mutex);
4814
4815 return event;
4816
4817 err_put_context:
4818 put_ctx(ctx);
4819 err_exit:
4820 return ERR_PTR(err);
4821}
4822EXPORT_SYMBOL_GPL(perf_event_create_kernel_counter);
4823
4465/* 4824/*
4466 * inherit a event from parent task to child task: 4825 * inherit a event from parent task to child task:
4467 */ 4826 */
@@ -4487,7 +4846,7 @@ inherit_event(struct perf_event *parent_event,
4487 child_event = perf_event_alloc(&parent_event->attr, 4846 child_event = perf_event_alloc(&parent_event->attr,
4488 parent_event->cpu, child_ctx, 4847 parent_event->cpu, child_ctx,
4489 group_leader, parent_event, 4848 group_leader, parent_event,
4490 GFP_KERNEL); 4849 NULL, GFP_KERNEL);
4491 if (IS_ERR(child_event)) 4850 if (IS_ERR(child_event))
4492 return child_event; 4851 return child_event;
4493 get_ctx(child_ctx); 4852 get_ctx(child_ctx);
@@ -4505,6 +4864,8 @@ inherit_event(struct perf_event *parent_event,
4505 if (parent_event->attr.freq) 4864 if (parent_event->attr.freq)
4506 child_event->hw.sample_period = parent_event->hw.sample_period; 4865 child_event->hw.sample_period = parent_event->hw.sample_period;
4507 4866
4867 child_event->overflow_handler = parent_event->overflow_handler;
4868
4508 /* 4869 /*
4509 * Link it up in the child's context: 4870 * Link it up in the child's context:
4510 */ 4871 */
@@ -4594,7 +4955,6 @@ __perf_event_exit_task(struct perf_event *child_event,
4594{ 4955{
4595 struct perf_event *parent_event; 4956 struct perf_event *parent_event;
4596 4957
4597 update_event_times(child_event);
4598 perf_event_remove_from_context(child_event); 4958 perf_event_remove_from_context(child_event);
4599 4959
4600 parent_event = child_event->parent; 4960 parent_event = child_event->parent;
@@ -4646,6 +5006,7 @@ void perf_event_exit_task(struct task_struct *child)
4646 * the events from it. 5006 * the events from it.
4647 */ 5007 */
4648 unclone_ctx(child_ctx); 5008 unclone_ctx(child_ctx);
5009 update_context_time(child_ctx);
4649 spin_unlock_irqrestore(&child_ctx->lock, flags); 5010 spin_unlock_irqrestore(&child_ctx->lock, flags);
4650 5011
4651 /* 5012 /*
@@ -4781,9 +5142,7 @@ int perf_event_init_task(struct task_struct *child)
4781 * We dont have to disable NMIs - we are only looking at 5142 * We dont have to disable NMIs - we are only looking at
4782 * the list, not manipulating it: 5143 * the list, not manipulating it:
4783 */ 5144 */
4784 list_for_each_entry_rcu(event, &parent_ctx->event_list, event_entry) { 5145 list_for_each_entry(event, &parent_ctx->group_list, group_entry) {
4785 if (event != event->group_leader)
4786 continue;
4787 5146
4788 if (!event->attr.inherit) { 5147 if (!event->attr.inherit) {
4789 inherited_all = 0; 5148 inherited_all = 0;