X-Git-Url: http://git.lttng.org/?p=lttng-modules.git;a=blobdiff_plain;f=lttng-context-perf-counters.c;h=d65f690805577a3f88a24d00395d8cc6ea2bafe5;hp=5327e6ef06956707a914d15c3d56e9924291d06b;hb=b3c40230ad700b12c39640d8593aece428a2702b;hpb=0478c519c5d71914799a3047749283fbfc18a95f

diff --git a/lttng-context-perf-counters.c b/lttng-context-perf-counters.c
index 5327e6ef..d65f6908 100644
--- a/lttng-context-perf-counters.c
+++ b/lttng-context-perf-counters.c
@@ -1,10 +1,23 @@
 /*
- * (C) Copyright	2009-2011 -
- * 		Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ * lttng-context-perf-counters.c
  *
  * LTTng performance monitoring counters (perf-counters) integration module.
  *
- * Dual LGPL v2.1/GPL v2 license.
+ * Copyright (C) 2009-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; only
+ * version 2.1 of the License.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
 #include <linux/module.h>
@@ -12,17 +25,19 @@
 #include <linux/perf_event.h>
 #include <linux/list.h>
 #include <linux/string.h>
-#include "ltt-events.h"
+#include <linux/cpu.h>
+#include "lttng-events.h"
 #include "wrapper/ringbuffer/frontend_types.h"
 #include "wrapper/vmalloc.h"
-#include "ltt-tracer.h"
+#include "wrapper/perf.h"
+#include "lttng-tracer.h"
 
 static
 size_t perf_counter_get_size(size_t offset)
 {
 	size_t size = 0;
 
-	size += lib_ring_buffer_align(offset, ltt_alignof(uint64_t));
+	size += lib_ring_buffer_align(offset, lttng_alignof(uint64_t));
 	size += sizeof(uint64_t);
 	return size;
 }
@@ -30,15 +45,19 @@ size_t perf_counter_get_size(size_t offset)
 static
 void perf_counter_record(struct lttng_ctx_field *field,
 			 struct lib_ring_buffer_ctx *ctx,
-			 struct ltt_channel *chan)
+			 struct lttng_channel *chan)
 {
 	struct perf_event *event;
 	uint64_t value;
 
-	event = field->u.perf_counter.e[ctx->cpu];
+	event = field->u.perf_counter->e[ctx->cpu];
 	if (likely(event)) {
-		event->pmu->read(event);
-		value = local64_read(&event->count);
+		if (unlikely(event->state == PERF_EVENT_STATE_ERROR)) {
+			value = 0;
+		} else {
+			event->pmu->read(event);
+			value = local64_read(&event->count);
+		}
 	} else {
 		/*
 		 * Perf chooses not to be clever and not to support enabling a
@@ -49,21 +68,30 @@ void perf_counter_record(struct lttng_ctx_field *field,
 		 */
 		value = 0;
 	}
-	lib_ring_buffer_align_ctx(ctx, ltt_alignof(value));
+	lib_ring_buffer_align_ctx(ctx, lttng_alignof(value));
 	chan->ops->event_write(ctx, &value, sizeof(value));
 }
 
+#if defined(CONFIG_PERF_EVENTS) && (LINUX_VERSION_CODE >= KERNEL_VERSION(3,0,99))
+static
+void overflow_callback(struct perf_event *event,
+		       struct perf_sample_data *data,
+		       struct pt_regs *regs)
+{
+}
+#else
 static
 void overflow_callback(struct perf_event *event, int nmi,
 		       struct perf_sample_data *data,
 		       struct pt_regs *regs)
 {
 }
+#endif
 
 static
 void lttng_destroy_perf_counter_field(struct lttng_ctx_field *field)
 {
-	struct perf_event **events = field->u.perf_counter.e;
+	struct perf_event **events = field->u.perf_counter->e;
 	int cpu;
 
 	get_online_cpus();
@@ -71,11 +99,12 @@ void lttng_destroy_perf_counter_field(struct lttng_ctx_field *field)
 		perf_event_release_kernel(events[cpu]);
 	put_online_cpus();
 #ifdef CONFIG_HOTPLUG_CPU
-	unregister_cpu_notifier(&field->u.perf_counter.nb);
+	unregister_cpu_notifier(&field->u.perf_counter->nb);
 #endif
 	kfree(field->event_field.name);
-	kfree(field->u.perf_counter.attr);
+	kfree(field->u.perf_counter->attr);
 	kfree(events);
+	kfree(field->u.perf_counter);
 }
 
 #ifdef CONFIG_HOTPLUG_CPU
@@ -92,27 +121,31 @@ void lttng_destroy_perf_counter_field(struct lttng_ctx_field *field)
  * soon).
  */
 static
-int __cpuinit lttng_perf_counter_cpu_hp_callback(struct notifier_block *nb,
+int lttng_perf_counter_cpu_hp_callback(struct notifier_block *nb,
 						 unsigned long action,
 						 void *hcpu)
 {
 	unsigned int cpu = (unsigned long) hcpu;
-	struct lttng_ctx_field *field =
-		container_of(nb, struct lttng_ctx_field, u.perf_counter.nb);
-	struct perf_event **events = field->u.perf_counter.e;
-	struct perf_event_attr *attr = field->u.perf_counter.attr;
+	struct lttng_perf_counter_field *perf_field =
+		container_of(nb, struct lttng_perf_counter_field, nb);
+	struct perf_event **events = perf_field->e;
+	struct perf_event_attr *attr = perf_field->attr;
 	struct perf_event *pevent;
 
-	if (!field->u.perf_counter.hp_enable)
+	if (!perf_field->hp_enable)
 		return NOTIFY_OK;
 
 	switch (action) {
 	case CPU_ONLINE:
 	case CPU_ONLINE_FROZEN:
-		pevent = perf_event_create_kernel_counter(attr,
+		pevent = wrapper_perf_event_create_kernel_counter(attr,
 				cpu, NULL, overflow_callback);
 		if (!pevent || IS_ERR(pevent))
 			return NOTIFY_BAD;
+		if (pevent->state == PERF_EVENT_STATE_ERROR) {
+			perf_event_release_kernel(pevent);
+			return NOTIFY_BAD;
+		}
 		barrier();	/* Create perf counter before setting event */
 		events[cpu] = pevent;
 		break;
@@ -137,6 +170,7 @@ int lttng_add_perf_counter_to_ctx(uint32_t type,
 				  struct lttng_ctx **ctx)
 {
 	struct lttng_ctx_field *field;
+	struct lttng_perf_counter_field *perf_field;
 	struct perf_event **events;
 	struct perf_event_attr *attr;
 	int ret;
@@ -147,7 +181,7 @@ int lttng_add_perf_counter_to_ctx(uint32_t type,
 	if (!events)
 		return -ENOMEM;
 
-	attr = kzalloc(sizeof(*field->u.perf_counter.attr), GFP_KERNEL);
+	attr = kzalloc(sizeof(struct perf_event_attr), GFP_KERNEL);
 	if (!attr) {
 		ret = -ENOMEM;
 		goto error_attr;
@@ -159,6 +193,14 @@ int lttng_add_perf_counter_to_ctx(uint32_t type,
 	attr->pinned = 1;
 	attr->disabled = 0;
 
+	perf_field = kzalloc(sizeof(struct lttng_perf_counter_field), GFP_KERNEL);
+	if (!perf_field) {
+		ret = -ENOMEM;
+		goto error_alloc_perf_field;
+	}
+	perf_field->e = events;
+	perf_field->attr = attr;
+
 	name_alloc = kstrdup(name, GFP_KERNEL);
 	if (!name_alloc) {
 		ret = -ENOMEM;
@@ -170,22 +212,30 @@ int lttng_add_perf_counter_to_ctx(uint32_t type,
 		ret = -ENOMEM;
 		goto append_context_error;
 	}
+	if (lttng_find_context(*ctx, name_alloc)) {
+		ret = -EEXIST;
+		goto find_error;
+	}
 
 #ifdef CONFIG_HOTPLUG_CPU
-	field->u.perf_counter.nb.notifier_call =
+	perf_field->nb.notifier_call =
 		lttng_perf_counter_cpu_hp_callback;
-	field->u.perf_counter.nb.priority = 0;
-	register_cpu_notifier(&field->u.perf_counter.nb);
+	perf_field->nb.priority = 0;
+	register_cpu_notifier(&perf_field->nb);
 #endif
 
 	get_online_cpus();
 	for_each_online_cpu(cpu) {
-		events[cpu] = perf_event_create_kernel_counter(attr,
+		events[cpu] = wrapper_perf_event_create_kernel_counter(attr,
 					cpu, NULL, overflow_callback);
 		if (!events[cpu] || IS_ERR(events[cpu])) {
 			ret = -EINVAL;
 			goto counter_error;
 		}
+		if (events[cpu]->state == PERF_EVENT_STATE_ERROR) {
+			ret = -EBUSY;
+			goto counter_busy;
+		}
 	}
 	put_online_cpus();
 
@@ -193,21 +243,21 @@ int lttng_add_perf_counter_to_ctx(uint32_t type,
 
 	field->event_field.name = name_alloc;
 	field->event_field.type.atype = atype_integer;
-	field->event_field.type.u.basic.integer.size = sizeof(unsigned long) * CHAR_BIT;
-	field->event_field.type.u.basic.integer.alignment = ltt_alignof(unsigned long) * CHAR_BIT;
-	field->event_field.type.u.basic.integer.signedness = is_signed_type(unsigned long);
+	field->event_field.type.u.basic.integer.size = sizeof(uint64_t) * CHAR_BIT;
+	field->event_field.type.u.basic.integer.alignment = lttng_alignof(uint64_t) * CHAR_BIT;
+	field->event_field.type.u.basic.integer.signedness = lttng_is_signed_type(uint64_t);
 	field->event_field.type.u.basic.integer.reverse_byte_order = 0;
 	field->event_field.type.u.basic.integer.base = 10;
 	field->event_field.type.u.basic.integer.encoding = lttng_encode_none;
 	field->get_size = perf_counter_get_size;
 	field->record = perf_counter_record;
-	field->u.perf_counter.e = events;
-	field->u.perf_counter.attr = attr;
-	field->u.perf_counter.hp_enable = 1;
+	field->u.perf_counter = perf_field;
+	perf_field->hp_enable = 1;
 
 	wrapper_vmalloc_sync_all();
 	return 0;
 
+counter_busy:
 counter_error:
 	for_each_online_cpu(cpu) {
 		if (events[cpu] && !IS_ERR(events[cpu]))
@@ -215,12 +265,15 @@ counter_error:
 	}
 	put_online_cpus();
 #ifdef CONFIG_HOTPLUG_CPU
-	unregister_cpu_notifier(&field->u.perf_counter.nb);
+	unregister_cpu_notifier(&perf_field->nb);
 #endif
+find_error:
 	lttng_remove_context_field(ctx, field);
 append_context_error:
 	kfree(name_alloc);
 name_alloc_error:
+	kfree(perf_field);
+error_alloc_perf_field:
 	kfree(attr);
 error_attr:
 	kfree(events);