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authorIngo Molnar <mingo@elte.hu>2009-11-21 14:07:23 +0100
committerIngo Molnar <mingo@elte.hu>2009-11-21 14:07:23 +0100
commit96200591a34f8ecb98481c626125df43a2463b55 (patch)
tree314c376b01f254d04f9aaf449b1f9147ad177fa6 /kernel/perf_event.c
parentMerge branch 'perf/urgent' into perf/core (diff)
parenthw-breakpoints, x86: Fix modular KVM build (diff)
downloadlinux-96200591a34f8ecb98481c626125df43a2463b55.tar.xz
linux-96200591a34f8ecb98481c626125df43a2463b55.zip
Merge branch 'tracing/hw-breakpoints' into perf/core
Conflicts: arch/x86/kernel/kprobes.c kernel/trace/Makefile Merge reason: hw-breakpoints perf integration is looking good in testing and in reviews, plus conflicts are mounting up - so merge & resolve. Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel/perf_event.c')
-rw-r--r--kernel/perf_event.c136
1 files changed, 133 insertions, 3 deletions
diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index 3256e36ad251..3852e2656bb0 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -29,6 +29,7 @@
#include <linux/kernel_stat.h>
#include <linux/perf_event.h>
#include <linux/ftrace_event.h>
+#include <linux/hw_breakpoint.h>
#include <asm/irq_regs.h>
@@ -1725,6 +1726,26 @@ static int perf_release(struct inode *inode, struct file *file)
return 0;
}
+int perf_event_release_kernel(struct perf_event *event)
+{
+ struct perf_event_context *ctx = event->ctx;
+
+ WARN_ON_ONCE(ctx->parent_ctx);
+ mutex_lock(&ctx->mutex);
+ perf_event_remove_from_context(event);
+ mutex_unlock(&ctx->mutex);
+
+ mutex_lock(&event->owner->perf_event_mutex);
+ list_del_init(&event->owner_entry);
+ mutex_unlock(&event->owner->perf_event_mutex);
+ put_task_struct(event->owner);
+
+ free_event(event);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(perf_event_release_kernel);
+
static int perf_event_read_size(struct perf_event *event)
{
int entry = sizeof(u64); /* value */
@@ -1750,7 +1771,7 @@ static int perf_event_read_size(struct perf_event *event)
return size;
}
-static u64 perf_event_read_value(struct perf_event *event)
+u64 perf_event_read_value(struct perf_event *event)
{
struct perf_event *child;
u64 total = 0;
@@ -1761,6 +1782,7 @@ static u64 perf_event_read_value(struct perf_event *event)
return total;
}
+EXPORT_SYMBOL_GPL(perf_event_read_value);
static int perf_event_read_entry(struct perf_event *event,
u64 read_format, char __user *buf)
@@ -4231,6 +4253,51 @@ static void perf_event_free_filter(struct perf_event *event)
#endif /* CONFIG_EVENT_PROFILE */
+#ifdef CONFIG_HAVE_HW_BREAKPOINT
+static void bp_perf_event_destroy(struct perf_event *event)
+{
+ release_bp_slot(event);
+}
+
+static const struct pmu *bp_perf_event_init(struct perf_event *bp)
+{
+ int err;
+ /*
+ * The breakpoint is already filled if we haven't created the counter
+ * through perf syscall
+ * FIXME: manage to get trigerred to NULL if it comes from syscalls
+ */
+ if (!bp->callback)
+ err = register_perf_hw_breakpoint(bp);
+ else
+ err = __register_perf_hw_breakpoint(bp);
+ if (err)
+ return ERR_PTR(err);
+
+ bp->destroy = bp_perf_event_destroy;
+
+ return &perf_ops_bp;
+}
+
+void perf_bp_event(struct perf_event *bp, void *regs)
+{
+ /* TODO */
+}
+#else
+static void bp_perf_event_destroy(struct perf_event *event)
+{
+}
+
+static const struct pmu *bp_perf_event_init(struct perf_event *bp)
+{
+ return NULL;
+}
+
+void perf_bp_event(struct perf_event *bp, void *regs)
+{
+}
+#endif
+
atomic_t perf_swevent_enabled[PERF_COUNT_SW_MAX];
static void sw_perf_event_destroy(struct perf_event *event)
@@ -4297,6 +4364,7 @@ perf_event_alloc(struct perf_event_attr *attr,
struct perf_event_context *ctx,
struct perf_event *group_leader,
struct perf_event *parent_event,
+ perf_callback_t callback,
gfp_t gfpflags)
{
const struct pmu *pmu;
@@ -4339,6 +4407,11 @@ perf_event_alloc(struct perf_event_attr *attr,
event->state = PERF_EVENT_STATE_INACTIVE;
+ if (!callback && parent_event)
+ callback = parent_event->callback;
+
+ event->callback = callback;
+
if (attr->disabled)
event->state = PERF_EVENT_STATE_OFF;
@@ -4373,6 +4446,11 @@ perf_event_alloc(struct perf_event_attr *attr,
pmu = tp_perf_event_init(event);
break;
+ case PERF_TYPE_BREAKPOINT:
+ pmu = bp_perf_event_init(event);
+ break;
+
+
default:
break;
}
@@ -4615,7 +4693,7 @@ SYSCALL_DEFINE5(perf_event_open,
}
event = perf_event_alloc(&attr, cpu, ctx, group_leader,
- NULL, GFP_KERNEL);
+ NULL, NULL, GFP_KERNEL);
err = PTR_ERR(event);
if (IS_ERR(event))
goto err_put_context;
@@ -4663,6 +4741,58 @@ err_put_context:
return err;
}
+/**
+ * perf_event_create_kernel_counter
+ *
+ * @attr: attributes of the counter to create
+ * @cpu: cpu in which the counter is bound
+ * @pid: task to profile
+ */
+struct perf_event *
+perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu,
+ pid_t pid, perf_callback_t callback)
+{
+ struct perf_event *event;
+ struct perf_event_context *ctx;
+ int err;
+
+ /*
+ * Get the target context (task or percpu):
+ */
+
+ ctx = find_get_context(pid, cpu);
+ if (IS_ERR(ctx))
+ return NULL;
+
+ event = perf_event_alloc(attr, cpu, ctx, NULL,
+ NULL, callback, GFP_KERNEL);
+ err = PTR_ERR(event);
+ if (IS_ERR(event))
+ goto err_put_context;
+
+ event->filp = NULL;
+ WARN_ON_ONCE(ctx->parent_ctx);
+ mutex_lock(&ctx->mutex);
+ perf_install_in_context(ctx, event, cpu);
+ ++ctx->generation;
+ mutex_unlock(&ctx->mutex);
+
+ event->owner = current;
+ get_task_struct(current);
+ mutex_lock(&current->perf_event_mutex);
+ list_add_tail(&event->owner_entry, &current->perf_event_list);
+ mutex_unlock(&current->perf_event_mutex);
+
+ return event;
+
+err_put_context:
+ if (err < 0)
+ put_ctx(ctx);
+
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(perf_event_create_kernel_counter);
+
/*
* inherit a event from parent task to child task:
*/
@@ -4688,7 +4818,7 @@ inherit_event(struct perf_event *parent_event,
child_event = perf_event_alloc(&parent_event->attr,
parent_event->cpu, child_ctx,
group_leader, parent_event,
- GFP_KERNEL);
+ NULL, GFP_KERNEL);
if (IS_ERR(child_event))
return child_event;
get_ctx(child_ctx);