X-Git-Url: http://git.lttng.org/?a=blobdiff_plain;f=liblttng-ust%2Flttng-context-vpid.c;h=f41119f9129e73e853c66512fa26851c826b5440;hb=06e646e04714e0e0f7537841107ab0528ef33a52;hp=fdf68fb1d17e0df10d1892e7e3bb4dfbc1d1cae2;hpb=e92f3e285939848f248af08f11a39a04a7fcf852;p=lttng-ust.git

diff --git a/liblttng-ust/lttng-context-vpid.c b/liblttng-ust/lttng-context-vpid.c
index fdf68fb1..f41119f9 100644
--- a/liblttng-ust/lttng-context-vpid.c
+++ b/liblttng-ust/lttng-context-vpid.c
@@ -1,42 +1,21 @@
 /*
- * lttng-context-vpid.c
- *
- * LTTng UST vpid 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 vpid 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>
 
-#ifdef __linux__
-static inline
-pid_t wrapper_getpid(void)
-{
-	return getpid();
-}
+#include "context-internal.h"
 
-void lttng_context_vpid_reset(void)
-{
-}
-#else
 /*
  * We cache the result to ensure we don't trigger a system call for
  * each event.
@@ -44,11 +23,16 @@ void lttng_context_vpid_reset(void)
 static pid_t cached_vpid;
 
 static inline
-pid_t wrapper_getpid(void)
+pid_t wrapper_getvpid(void)
 {
-	if (caa_unlikely(!cached_vpid))
-		cached_vpid = getpid();
-	return cached_vpid;
+	pid_t vpid;
+
+	vpid = CMM_LOAD_SHARED(cached_vpid);
+	if (caa_unlikely(!vpid)) {
+		vpid = getpid();
+		CMM_STORE_SHARED(cached_vpid, vpid);
+	}
+	return vpid;
 }
 
 /*
@@ -57,12 +41,11 @@ pid_t wrapper_getpid(void)
  */
 void lttng_context_vpid_reset(void)
 {
-	cached_vpid = 0;
+	CMM_STORE_SHARED(cached_vpid, 0);
 }
-#endif
 
 static
-size_t vpid_get_size(size_t offset)
+size_t vpid_get_size(struct lttng_ctx_field *field, size_t offset)
 {
 	size_t size = 0;
 
@@ -74,13 +57,19 @@ size_t vpid_get_size(size_t offset)
 static
 void vpid_record(struct lttng_ctx_field *field,
 		 struct lttng_ust_lib_ring_buffer_ctx *ctx,
-		 struct ltt_channel *chan)
+		 struct lttng_channel *chan)
 {
-	pid_t pid;
+	pid_t vpid = wrapper_getvpid();
 
-	pid = wrapper_getpid();
-	lib_ring_buffer_align_ctx(ctx, lttng_alignof(pid));
-	chan->ops->event_write(ctx, &pid, sizeof(pid));
+	lib_ring_buffer_align_ctx(ctx, lttng_alignof(vpid));
+	chan->ops->event_write(ctx, &vpid, sizeof(vpid));
+}
+
+static
+void vpid_get_value(struct lttng_ctx_field *field,
+		struct lttng_ctx_value *value)
+{
+	value->u.s64 = wrapper_getvpid();
 }
 
 int lttng_add_vpid_to_ctx(struct lttng_ctx **ctx)
@@ -96,13 +85,15 @@ int lttng_add_vpid_to_ctx(struct lttng_ctx **ctx)
 	}
 	field->event_field.name = "vpid";
 	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.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 = vpid_get_size;
 	field->record = vpid_record;
+	field->get_value = vpid_get_value;
+	lttng_context_update(*ctx);
 	return 0;
 }