From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Date: Wed, 25 May 2011 22:15:38 +0000 (-0400)
Subject: Write context fields into trace
X-Git-Tag: v2.0-pre1~86
X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=f167620537b558f8fabd6912d4ea5c46a92cd877;p=lttng-modules.git

Write context fields into trace

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
---

diff --git a/ltt-events.h b/ltt-events.h
index 1a5b5d5c..bea5af1c 100644
--- a/ltt-events.h
+++ b/ltt-events.h
@@ -120,7 +120,10 @@ struct lttng_event_field {
 struct lttng_ctx_field {
 	const char *name;
 	struct lttng_type type;
-	void *callback;
+	size_t (*get_size)(size_t offset);
+	void (*record)(struct lttng_ctx_field *field,
+		       struct lib_ring_buffer_ctx *ctx,
+		       struct ltt_channel *chan);
 	union {
 		struct {
 			struct perf_event **e;	/* per-cpu array */
@@ -161,6 +164,7 @@ struct ltt_event {
 	struct ltt_channel *chan;
 	const struct lttng_event_desc *desc;
 	void *filter;
+	struct lttng_ctx *ctx;
 	enum lttng_kernel_instrumentation instrumentation;
 	union {
 		struct {
@@ -202,6 +206,7 @@ struct ltt_channel_ops {
 struct ltt_channel {
 	unsigned int id;
 	struct channel *chan;		/* Channel buffers */
+	struct lttng_ctx *ctx;
 	/* Event ID management */
 	struct ltt_session *session;
 	struct file *file;		/* File associated to channel */
@@ -215,6 +220,7 @@ struct ltt_channel {
 
 struct ltt_session {
 	int active;			/* Is trace session active ? */
+	struct lttng_ctx *ctx;
 	struct file *file;		/* File associated to session */
 	struct ltt_channel *metadata;	/* Metadata channel */
 	struct list_head chan;		/* Channel list head */
diff --git a/ltt-ring-buffer-client.h b/ltt-ring-buffer-client.h
index 1c3d014d..8095eb6e 100644
--- a/ltt-ring-buffer-client.h
+++ b/ltt-ring-buffer-client.h
@@ -55,6 +55,32 @@ static inline notrace u64 lib_ring_buffer_clock_read(struct channel *chan)
 	return trace_clock_read64();
 }
 
+static inline
+size_t ctx_get_size(size_t offset, struct lttng_ctx *ctx)
+{
+	int i;
+	size_t orig_offset = offset;
+
+	if (likely(!ctx))
+		return 0;
+	for (i = 0; i < ctx->nr_fields; i++)
+		offset += ctx->fields[i].get_size(offset);
+	return offset - orig_offset;
+}
+
+static inline
+void ctx_record(struct lib_ring_buffer_ctx *bufctx,
+		struct ltt_channel *chan,
+		struct lttng_ctx *ctx)
+{
+	int i;
+
+	if (likely(!ctx))
+		return;
+	for (i = 0; i < ctx->nr_fields; i++)
+		ctx->fields[i].record(&ctx->fields[i], bufctx, chan);
+}
+
 /*
  * record_header_size - Calculate the header size and padding necessary.
  * @config: ring buffer instance configuration
@@ -75,6 +101,7 @@ unsigned char record_header_size(const struct lib_ring_buffer_config *config,
 				 struct lib_ring_buffer_ctx *ctx)
 {
 	struct ltt_channel *ltt_chan = channel_get_private(chan);
+	struct ltt_event *event = ctx->priv;
 	size_t orig_offset = offset;
 	size_t padding;
 
@@ -113,6 +140,9 @@ unsigned char record_header_size(const struct lib_ring_buffer_config *config,
 	default:
 		WARN_ON_ONCE(1);
 	}
+	offset += ctx_get_size(offset, event->ctx);
+	offset += ctx_get_size(offset, ltt_chan->ctx);
+	offset += ctx_get_size(offset, ltt_chan->session->ctx);
 
 	*pre_header_padding = padding;
 	return offset - orig_offset;
@@ -140,6 +170,7 @@ void ltt_write_event_header(const struct lib_ring_buffer_config *config,
 			    uint32_t event_id)
 {
 	struct ltt_channel *ltt_chan = channel_get_private(ctx->chan);
+	struct ltt_event *event = ctx->priv;
 
 	if (unlikely(ctx->rflags))
 		goto slow_path;
@@ -166,6 +197,11 @@ void ltt_write_event_header(const struct lib_ring_buffer_config *config,
 	default:
 		WARN_ON_ONCE(1);
 	}
+
+	ctx_record(ctx, ltt_chan, event->ctx);
+	ctx_record(ctx, ltt_chan, ltt_chan->ctx);
+	ctx_record(ctx, ltt_chan, ltt_chan->session->ctx);
+
 	return;
 
 slow_path:
@@ -177,6 +213,7 @@ void ltt_write_event_header_slow(const struct lib_ring_buffer_config *config,
 				 uint32_t event_id)
 {
 	struct ltt_channel *ltt_chan = channel_get_private(ctx->chan);
+	struct ltt_event *event = ctx->priv;
 
 	switch (ltt_chan->header_type) {
 	case 1:	/* compact */
@@ -223,6 +260,9 @@ void ltt_write_event_header_slow(const struct lib_ring_buffer_config *config,
 	default:
 		WARN_ON_ONCE(1);
 	}
+	ctx_record(ctx, ltt_chan, event->ctx);
+	ctx_record(ctx, ltt_chan, ltt_chan->ctx);
+	ctx_record(ctx, ltt_chan, ltt_chan->session->ctx);
 }
 
 static const struct lib_ring_buffer_config client_config;
diff --git a/probes/lttng-context-pid.c b/probes/lttng-context-pid.c
index 669e593f..adb14c36 100644
--- a/probes/lttng-context-pid.c
+++ b/probes/lttng-context-pid.c
@@ -15,6 +15,16 @@
 #include "../wrapper/vmalloc.h"
 #include "../ltt-tracer.h"
 
+static
+size_t pid_get_size(size_t offset)
+{
+	size_t size = 0;
+
+	size += lib_ring_buffer_align(offset, ltt_alignof(pid_t));
+	size += sizeof(pid_t);
+	return size;
+}
+
 static
 void pid_record(struct lttng_ctx_field *field,
 		struct lib_ring_buffer_ctx *ctx,
@@ -43,7 +53,8 @@ int lttng_add_pid_to_ctx(struct lttng_ctx **ctx)
 	field->type.u.basic.integer.reverse_byte_order = 0;
 	field->type.u.basic.integer.base = 10;
 	field->type.u.basic.integer.encoding = lttng_encode_none;
-	field->callback = pid_record;
+	field->get_size = pid_get_size;
+	field->record = pid_record;
 	wrapper_vmalloc_sync_all();
 	return 0;
 }
diff --git a/probes/lttng-events.h b/probes/lttng-events.h
index beedb22b..b32921ca 100644
--- a/probes/lttng-events.h
+++ b/probes/lttng-events.h
@@ -521,7 +521,7 @@ static void __event_probe__##_name(void *__data, _proto)		      \
 		return;							      \
 	__event_len = __event_get_size__##_name(__dynamic_len, _args);	      \
 	__event_align = __event_get_align__##_name(_args);		      \
-	lib_ring_buffer_ctx_init(&ctx, __chan->chan, NULL, __event_len,	      \
+	lib_ring_buffer_ctx_init(&ctx, __chan->chan, __event, __event_len,    \
 				 __event_align, -1);			      \
 	__ret = __chan->ops->event_reserve(&ctx, __event->id);		      \
 	if (__ret < 0)							      \
diff --git a/probes/lttng-ftrace.c b/probes/lttng-ftrace.c
index c18a4702..476d6bce 100644
--- a/probes/lttng-ftrace.c
+++ b/probes/lttng-ftrace.c
@@ -36,7 +36,7 @@ void lttng_ftrace_handler(unsigned long ip, unsigned long parent_ip, void **data
 
 	if (!ACCESS_ONCE(chan->session->active))
 		return;
-	lib_ring_buffer_ctx_init(&ctx, chan->chan, NULL,
+	lib_ring_buffer_ctx_init(&ctx, chan->chan, event,
 				 sizeof(payload), ltt_alignof(payload), -1);
 	ret = chan->ops->event_reserve(&ctx, event->id);
 	if (ret < 0)
diff --git a/probes/lttng-kprobes.c b/probes/lttng-kprobes.c
index 481807de..89cfe073 100644
--- a/probes/lttng-kprobes.c
+++ b/probes/lttng-kprobes.c
@@ -27,7 +27,7 @@ int lttng_kprobes_handler_pre(struct kprobe *p, struct pt_regs *regs)
 
 	if (!ACCESS_ONCE(chan->session->active))
 		return 0;
-	lib_ring_buffer_ctx_init(&ctx, chan->chan, NULL, sizeof(data),
+	lib_ring_buffer_ctx_init(&ctx, chan->chan, event, sizeof(data),
 				 ltt_alignof(data), -1);
 	ret = chan->ops->event_reserve(&ctx, event->id);
 	if (ret < 0)
diff --git a/probes/lttng-perf-counters.c b/probes/lttng-perf-counters.c
index 740c1d94..06a4a7ce 100644
--- a/probes/lttng-perf-counters.c
+++ b/probes/lttng-perf-counters.c
@@ -23,6 +23,16 @@
 static DEFINE_MUTEX(perf_counter_mutex);
 static LIST_HEAD(perf_counter_contexts);
 
+static
+size_t perf_counter_get_size(size_t offset)
+{
+	size_t size = 0;
+
+	size += lib_ring_buffer_align(offset, ltt_alignof(uint64_t));
+	size += sizeof(uint64_t);
+	return size;
+}
+
 static
 void perf_counter_record(struct lttng_ctx_field *field,
 			 struct lib_ring_buffer_ctx *ctx,
@@ -112,7 +122,8 @@ int lttng_add_perf_counter_to_ctx(uint32_t type,
 	field->type.u.basic.integer.reverse_byte_order = 0;
 	field->type.u.basic.integer.base = 10;
 	field->type.u.basic.integer.encoding = lttng_encode_none;
-	field->callback = perf_counter_record;
+	field->get_size = perf_counter_get_size;
+	field->record = perf_counter_record;
 	field->u.perf_counter.e = events;
 	field->u.perf_counter.attr = attr;