/*
* lttng-context.c
*
- * Copyright 2011 (c) - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
- *
* LTTng trace/channel/event context management.
*
- * Dual LGPL v2.1/GPL v2 license.
+ * Copyright (C) 2011-2012 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>
#include "lttng-events.h"
#include "lttng-tracer.h"
+/*
+ * The filter implementation requires that two consecutive "get" for the
+ * same context performed by the same thread return the same result.
+ */
+
+/*
+ * Static array of contexts, for $ctx filters.
+ */
+struct lttng_ctx *lttng_static_ctx;
+
int lttng_find_context(struct lttng_ctx *ctx, const char *name)
{
unsigned int i;
}
EXPORT_SYMBOL_GPL(lttng_find_context);
+int lttng_get_context_index(struct lttng_ctx *ctx, const char *name)
+{
+ unsigned int i;
+
+ if (!ctx)
+ return -1;
+ for (i = 0; i < ctx->nr_fields; i++) {
+ /* Skip allocated (but non-initialized) contexts */
+ if (!ctx->fields[i].event_field.name)
+ continue;
+ if (!strcmp(ctx->fields[i].event_field.name, name))
+ return i;
+ }
+ return -1;
+}
+EXPORT_SYMBOL_GPL(lttng_get_context_index);
+
/*
* Note: as we append context information, the pointer location may change.
*/
*ctx_p = kzalloc(sizeof(struct lttng_ctx), GFP_KERNEL);
if (!*ctx_p)
return NULL;
+ (*ctx_p)->largest_align = 1;
}
ctx = *ctx_p;
if (ctx->nr_fields + 1 > ctx->allocated_fields) {
}
EXPORT_SYMBOL_GPL(lttng_append_context);
+/*
+ * lttng_context_update() should be called at least once between context
+ * modification and trace start.
+ */
+void lttng_context_update(struct lttng_ctx *ctx)
+{
+ int i;
+ size_t largest_align = 8; /* in bits */
+
+ for (i = 0; i < ctx->nr_fields; i++) {
+ struct lttng_type *type;
+ size_t field_align = 8;
+
+ type = &ctx->fields[i].event_field.type;
+ switch (type->atype) {
+ case atype_integer:
+ field_align = type->u.basic.integer.alignment;
+ break;
+ case atype_array:
+ {
+ struct lttng_basic_type *btype;
+
+ btype = &type->u.array.elem_type;
+ switch (btype->atype) {
+ case atype_integer:
+ field_align = btype->u.basic.integer.alignment;
+ break;
+ case atype_string:
+ break;
+
+ case atype_array:
+ case atype_sequence:
+ default:
+ WARN_ON_ONCE(1);
+ break;
+ }
+ break;
+ }
+ case atype_sequence:
+ {
+ struct lttng_basic_type *btype;
+
+ btype = &type->u.sequence.length_type;
+ switch (btype->atype) {
+ case atype_integer:
+ field_align = btype->u.basic.integer.alignment;
+ break;
+
+ case atype_string:
+ case atype_array:
+ case atype_sequence:
+ default:
+ WARN_ON_ONCE(1);
+ break;
+ }
+
+ btype = &type->u.sequence.elem_type;
+ switch (btype->atype) {
+ case atype_integer:
+ field_align = max_t(size_t,
+ field_align,
+ btype->u.basic.integer.alignment);
+ break;
+
+ case atype_string:
+ break;
+
+ case atype_array:
+ case atype_sequence:
+ default:
+ WARN_ON_ONCE(1);
+ break;
+ }
+ break;
+ }
+ case atype_string:
+ break;
+
+ case atype_enum:
+ default:
+ WARN_ON_ONCE(1);
+ break;
+ }
+ largest_align = max_t(size_t, largest_align, field_align);
+ }
+ ctx->largest_align = largest_align >> 3; /* bits to bytes */
+}
+
/*
* Remove last context field.
*/
kfree(ctx->fields);
kfree(ctx);
}
+
+int lttng_context_init(void)
+{
+ int ret;
+
+ ret = lttng_add_vpid_to_ctx(<tng_static_ctx);
+ if (ret) {
+ printk(KERN_WARNING "Cannot add context lttng_add_procname_to_ctx");
+ }
+#if 0 //TODO
+ ret = lttng_add_pid_to_ctx(<tng_static_ctx);
+ if (ret) {
+ printk(KERN_WARNING "Cannot add context lttng_add_pthread_id_to_ctx");
+ }
+ ret = lttng_add_procname_to_ctx(<tng_static_ctx);
+ if (ret) {
+ printk(KERN_WARNING "Cannot add context lttng_add_vtid_to_ctx");
+ }
+ ret = lttng_add_prio_to_ctx(<tng_static_ctx);
+ if (ret) {
+ printk(KERN_WARNING "Cannot add context lttng_add_vpid_to_ctx");
+ }
+ ret = lttng_add_nice_to_ctx(<tng_static_ctx);
+ if (ret) {
+ printk(KERN_WARNING "Cannot add context lttng_add_procname_to_ctx");
+ }
+ ret = lttng_add_tid_to_ctx(<tng_static_ctx);
+ if (ret) {
+ printk(KERN_WARNING "Cannot add context lttng_add_procname_to_ctx");
+ }
+ ret = lttng_add_vtid_to_ctx(<tng_static_ctx);
+ if (ret) {
+ printk(KERN_WARNING "Cannot add context lttng_add_procname_to_ctx");
+ }
+ ret = lttng_add_ppid_to_ctx(<tng_static_ctx);
+ if (ret) {
+ printk(KERN_WARNING "Cannot add context lttng_add_procname_to_ctx");
+ }
+ ret = lttng_add_vppid_to_ctx(<tng_static_ctx);
+ if (ret) {
+ printk(KERN_WARNING "Cannot add context lttng_add_procname_to_ctx");
+ }
+ ret = lttng_add_hostname_to_ctx(<tng_static_ctx);
+ if (ret) {
+ printk(KERN_WARNING "Cannot add context lttng_add_procname_to_ctx");
+ }
+#endif
+ return 0;
+}
+
+void lttng_context_exit(void)
+{
+ lttng_destroy_context(lttng_static_ctx);
+ lttng_static_ctx = NULL;
+}