X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=liblttng-ust%2Flttng-context-vtid.c;h=9b91e57c5dd962b7991a03e81978ff0e409177a7;hb=daacdbfc04fe07ecff0a0d1878b4f48d38912c78;hp=f28e470a38c91be3e88c7b1d1fcd42c591d73c67;hpb=16adecf1f2e80025667ed53f4905e725894f076a;p=lttng-ust.git

diff --git a/liblttng-ust/lttng-context-vtid.c b/liblttng-ust/lttng-context-vtid.c
index f28e470a..9b91e57c 100644
--- a/liblttng-ust/lttng-context-vtid.c
+++ b/liblttng-ust/lttng-context-vtid.c
@@ -1,33 +1,22 @@
 /*
- * lttng-context-vtid.c
- *
- * LTTng UST vtid context.
+ * SPDX-License-Identifier: LGPL-2.1-only
  *
  * 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
+ * LTTng UST vtid context.
  */
 
 #define _LGPL_SOURCE
+#include <stddef.h>
 #include <sys/types.h>
 #include <unistd.h>
 #include <lttng/ust-events.h>
 #include <lttng/ust-tracer.h>
 #include <lttng/ringbuffer-config.h>
-#include <lttng/ust-tid.h>
+#include <ust-tid.h>
 #include <urcu/tls-compat.h>
+
+#include "context-internal.h"
 #include "lttng-tracer-core.h"
 
 /*
@@ -43,11 +32,11 @@ static DEFINE_URCU_TLS(pid_t, cached_vtid);
  */
 void lttng_context_vtid_reset(void)
 {
-	URCU_TLS(cached_vtid) = 0;
+	CMM_STORE_SHARED(URCU_TLS(cached_vtid), 0);
 }
 
 static
-size_t vtid_get_size(struct lttng_ctx_field *field, size_t offset)
+size_t vtid_get_size(struct lttng_ust_ctx_field *field, size_t offset)
 {
 	size_t size = 0;
 
@@ -56,30 +45,40 @@ size_t vtid_get_size(struct lttng_ctx_field *field, size_t offset)
 	return size;
 }
 
+static inline
+pid_t wrapper_getvtid(void)
+{
+	pid_t vtid;
+
+	vtid = CMM_LOAD_SHARED(URCU_TLS(cached_vtid));
+	if (caa_unlikely(!vtid)) {
+		vtid = lttng_gettid();
+		CMM_STORE_SHARED(URCU_TLS(cached_vtid), vtid);
+	}
+	return vtid;
+}
+
 static
-void vtid_record(struct lttng_ctx_field *field,
+void vtid_record(struct lttng_ust_ctx_field *field,
 		 struct lttng_ust_lib_ring_buffer_ctx *ctx,
 		 struct lttng_channel *chan)
 {
-	if (caa_unlikely(!URCU_TLS(cached_vtid)))
-		URCU_TLS(cached_vtid) = gettid();
-	lib_ring_buffer_align_ctx(ctx, lttng_alignof(URCU_TLS(cached_vtid)));
-	chan->ops->event_write(ctx, &URCU_TLS(cached_vtid),
-		sizeof(URCU_TLS(cached_vtid)));
+	pid_t vtid = wrapper_getvtid();
+
+	lib_ring_buffer_align_ctx(ctx, lttng_alignof(vtid));
+	chan->ops->event_write(ctx, &vtid, sizeof(vtid));
 }
 
 static
-void vtid_get_value(struct lttng_ctx_field *field,
-		struct lttng_ctx_value *value)
+void vtid_get_value(struct lttng_ust_ctx_field *field,
+		struct lttng_ust_ctx_value *value)
 {
-	if (caa_unlikely(!URCU_TLS(cached_vtid)))
-		URCU_TLS(cached_vtid) = gettid();
-	value->u.s64 = URCU_TLS(cached_vtid);
+	value->u.s64 = wrapper_getvtid();
 }
 
-int lttng_add_vtid_to_ctx(struct lttng_ctx **ctx)
+int lttng_add_vtid_to_ctx(struct lttng_ust_ctx **ctx)
 {
-	struct lttng_ctx_field *field;
+	struct lttng_ust_ctx_field *field;
 
 	field = lttng_append_context(ctx);
 	if (!field)
@@ -88,14 +87,14 @@ int lttng_add_vtid_to_ctx(struct lttng_ctx **ctx)
 		lttng_remove_context_field(ctx, field);
 		return -EEXIST;
 	}
-	field->event_field.name = "vtid";
-	field->event_field.type.atype = atype_integer;
-	field->event_field.type.u.basic.integer.size = sizeof(pid_t) * CHAR_BIT;
-	field->event_field.type.u.basic.integer.alignment = lttng_alignof(pid_t) * CHAR_BIT;
-	field->event_field.type.u.basic.integer.signedness = lttng_is_signed_type(pid_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->event_field->name = "vtid";
+	field->event_field->type.atype = atype_integer;
+	field->event_field->type.u.integer.size = sizeof(pid_t) * CHAR_BIT;
+	field->event_field->type.u.integer.alignment = lttng_alignof(pid_t) * CHAR_BIT;
+	field->event_field->type.u.integer.signedness = lttng_is_signed_type(pid_t);
+	field->event_field->type.u.integer.reverse_byte_order = 0;
+	field->event_field->type.u.integer.base = 10;
+	field->event_field->type.u.integer.encoding = lttng_encode_none;
 	field->get_size = vtid_get_size;
 	field->record = vtid_record;
 	field->get_value = vtid_get_value;