/*
* 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>
*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.
*/