X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=lttng-context.c;h=eca58ce1873b3ab18c25001ac362a086dda6ecbd;hb=refs%2Fheads%2Fstable-2.7;hp=17d819d90121f7e0c7146361e115197939f6fce3;hpb=886d51a3d7ed5fa6b41d7f19b3e14ae6c535a44c;p=lttng-modules.git

diff --git a/lttng-context.c b/lttng-context.c
index 17d819d9..eca58ce1 100644
--- a/lttng-context.c
+++ b/lttng-context.c
@@ -28,6 +28,16 @@
 #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;
@@ -43,6 +53,23 @@ int lttng_find_context(struct lttng_ctx *ctx, const char *name)
 }
 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.
  */
@@ -55,6 +82,7 @@ struct lttng_ctx_field *lttng_append_context(struct lttng_ctx **ctx_p)
 		*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) {
@@ -75,6 +103,94 @@ struct lttng_ctx_field *lttng_append_context(struct lttng_ctx **ctx_p)
 }
 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.
  */
@@ -103,3 +219,61 @@ void lttng_destroy_context(struct lttng_ctx *ctx)
 	kfree(ctx->fields);
 	kfree(ctx);
 }
+
+int lttng_context_init(void)
+{
+	int ret;
+
+	ret = lttng_add_hostname_to_ctx(&lttng_static_ctx);
+	if (ret) {
+		printk(KERN_WARNING "Cannot add context lttng_add_hostname_to_ctx");
+	}
+	ret = lttng_add_nice_to_ctx(&lttng_static_ctx);
+	if (ret) {
+		printk(KERN_WARNING "Cannot add context lttng_add_nice_to_ctx");
+	}
+	ret = lttng_add_pid_to_ctx(&lttng_static_ctx);
+	if (ret) {
+		printk(KERN_WARNING "Cannot add context lttng_add_pid_to_ctx");
+	}
+	ret = lttng_add_ppid_to_ctx(&lttng_static_ctx);
+	if (ret) {
+		printk(KERN_WARNING "Cannot add context lttng_add_ppid_to_ctx");
+	}
+	ret = lttng_add_prio_to_ctx(&lttng_static_ctx);
+	if (ret) {
+		printk(KERN_WARNING "Cannot add context lttng_add_prio_to_ctx");
+	}
+	ret = lttng_add_procname_to_ctx(&lttng_static_ctx);
+	if (ret) {
+		printk(KERN_WARNING "Cannot add context lttng_add_procname_to_ctx");
+	}
+	ret = lttng_add_tid_to_ctx(&lttng_static_ctx);
+	if (ret) {
+		printk(KERN_WARNING "Cannot add context lttng_add_tid_to_ctx");
+	}
+	ret = lttng_add_vppid_to_ctx(&lttng_static_ctx);
+	if (ret) {
+		printk(KERN_WARNING "Cannot add context lttng_add_vppid_to_ctx");
+	}
+	ret = lttng_add_vtid_to_ctx(&lttng_static_ctx);
+	if (ret) {
+		printk(KERN_WARNING "Cannot add context lttng_add_vtid_to_ctx");
+	}
+	ret = lttng_add_vpid_to_ctx(&lttng_static_ctx);
+	if (ret) {
+		printk(KERN_WARNING "Cannot add context lttng_add_vpid_to_ctx");
+	}
+	ret = lttng_add_cpu_id_to_ctx(&lttng_static_ctx);
+	if (ret) {
+		printk(KERN_WARNING "Cannot add context lttng_add_cpu_id_to_ctx");
+	}
+	/* TODO: perf counters for filtering */
+	return 0;
+}
+
+void lttng_context_exit(void)
+{
+	lttng_destroy_context(lttng_static_ctx);
+	lttng_static_ctx = NULL;
+}