X-Git-Url: http://drtracing.org/?a=blobdiff_plain;f=ltt-ring-buffer-client.h;h=aa763837a974271d9df6932f23771a82bc8e840d;hb=d793d5e111fe1436fb8e15daa5d7fb1be8987bb4;hp=5ce710cef7285c3da0000d11012ad5fd72f416d1;hpb=f3bc08c50e1b302bceea699027d889fd6d9af525;p=deliverable%2Flttng-modules.git

diff --git a/ltt-ring-buffer-client.h b/ltt-ring-buffer-client.h
index 5ce710ce..aa763837 100644
--- a/ltt-ring-buffer-client.h
+++ b/ltt-ring-buffer-client.h
@@ -10,10 +10,203 @@
 
 #include <linux/module.h>
 #include <linux/types.h>
+#include "wrapper/vmalloc.h"	/* for wrapper_vmalloc_sync_all() */
 #include "wrapper/trace-clock.h"
 #include "ltt-events.h"
 #include "ltt-tracer.h"
 
+/*
+ * Keep the natural field alignment for _each field_ within this structure if
+ * you ever add/remove a field from this header. Packed attribute is not used
+ * because gcc generates poor code on at least powerpc and mips. Don't ever
+ * let gcc add padding between the structure elements.
+ */
+struct packet_header {
+	uint32_t magic;			/*
+					 * Trace magic number.
+					 * contains endianness information.
+					 */
+	uint8_t trace_uuid[16];
+	uint32_t stream_id;
+	uint64_t timestamp_begin;	/* Cycle count at subbuffer start */
+	uint64_t timestamp_end;	/* Cycle count at subbuffer end */
+	uint32_t content_size;		/* Size of data in subbuffer */
+	uint32_t packet_size;		/* Subbuffer size (include padding) */
+	uint32_t events_lost;		/*
+					 * Events lost in this subbuffer since
+					 * the beginning of the trace.
+					 * (may overflow)
+					 */
+#if 0
+	uint64_t start_time_sec;	/* NTP-corrected start time */
+	uint64_t start_time_usec;
+	uint64_t start_freq;		/*
+					 * Frequency at trace start,
+				 * used all along the trace.
+					 */
+	uint32_t freq_scale;		/* Frequency scaling (divisor) */
+#endif //0
+	uint8_t header_end[0];		/* End of header */
+};
+
+
+static inline notrace u64 lib_ring_buffer_clock_read(struct channel *chan)
+{
+	return trace_clock_read64();
+}
+
+/*
+ * record_header_size - Calculate the header size and padding necessary.
+ * @config: ring buffer instance configuration
+ * @chan: channel
+ * @offset: offset in the write buffer
+ * @data_size: size of the payload
+ * @pre_header_padding: padding to add before the header (output)
+ * @rflags: reservation flags
+ * @ctx: reservation context
+ *
+ * Returns the event header size (including padding).
+ *
+ * Important note :
+ * The event header must be 32-bits. The total offset calculated here :
+ *
+ * Alignment of header struct on 32 bits (min arch size, header size)
+ * + sizeof(header struct)  (32-bits)
+ * + (opt) u16 (ext. event id)
+ * + (opt) u16 (event_size)
+ *             (if event_size == LTT_MAX_SMALL_SIZE, has ext. event size)
+ * + (opt) u32 (ext. event size)
+ * + (opt) u64 full TSC (aligned on min(64-bits, arch size))
+ *
+ * The payload must itself determine its own alignment from the biggest type it
+ * contains.
+ */
+static __inline__
+unsigned char record_header_size(const struct lib_ring_buffer_config *config,
+				 struct channel *chan, size_t offset,
+				 size_t data_size, size_t *pre_header_padding,
+				 unsigned int rflags,
+				 struct lib_ring_buffer_ctx *ctx)
+{
+	size_t orig_offset = offset;
+	size_t padding;
+
+	BUILD_BUG_ON(sizeof(struct event_header) != sizeof(u32));
+
+	padding = lib_ring_buffer_align(offset,
+					sizeof(struct event_header));
+	offset += padding;
+	offset += sizeof(struct event_header);
+
+	if (unlikely(rflags)) {
+		switch (rflags) {
+		case LTT_RFLAG_ID_SIZE_TSC:
+			offset += sizeof(u16) + sizeof(u16);
+			if (data_size >= LTT_MAX_SMALL_SIZE)
+				offset += sizeof(u32);
+			offset += lib_ring_buffer_align(offset, sizeof(u64));
+			offset += sizeof(u64);
+			break;
+		case LTT_RFLAG_ID_SIZE:
+			offset += sizeof(u16) + sizeof(u16);
+			if (data_size >= LTT_MAX_SMALL_SIZE)
+				offset += sizeof(u32);
+			break;
+		case LTT_RFLAG_ID:
+			offset += sizeof(u16);
+			break;
+		}
+	}
+
+	*pre_header_padding = padding;
+	return offset - orig_offset;
+}
+
+#include "wrapper/ringbuffer/api.h"
+
+extern
+void ltt_write_event_header_slow(const struct lib_ring_buffer_config *config,
+				 struct lib_ring_buffer_ctx *ctx,
+				 u16 eID, u32 event_size);
+
+/*
+ * ltt_write_event_header
+ *
+ * Writes the event header to the offset (already aligned on 32-bits).
+ *
+ * @config: ring buffer instance configuration
+ * @ctx: reservation context
+ * @eID : event ID
+ * @event_size : size of the event, excluding the event header.
+ */
+static __inline__
+void ltt_write_event_header(const struct lib_ring_buffer_config *config,
+			    struct lib_ring_buffer_ctx *ctx,
+			    u16 eID, u32 event_size)
+{
+	struct event_header header;
+
+	if (unlikely(ctx->rflags))
+		goto slow_path;
+
+	header.id_time = eID << LTT_TSC_BITS;
+	header.id_time |= (u32)ctx->tsc & LTT_TSC_MASK;
+	lib_ring_buffer_write(config, ctx, &header, sizeof(header));
+
+slow_path:
+	ltt_write_event_header_slow(config, ctx, eID, event_size);
+}
+
+void ltt_write_event_header_slow(const struct lib_ring_buffer_config *config,
+				   struct lib_ring_buffer_ctx *ctx,
+				   u16 eID, u32 event_size)
+{
+	struct event_header header;
+	u16 small_size;
+
+	switch (ctx->rflags) {
+	case LTT_RFLAG_ID_SIZE_TSC:
+		header.id_time = 29 << LTT_TSC_BITS;
+		break;
+	case LTT_RFLAG_ID_SIZE:
+		header.id_time = 30 << LTT_TSC_BITS;
+		break;
+	case LTT_RFLAG_ID:
+		header.id_time = 31 << LTT_TSC_BITS;
+		break;
+	default:
+		WARN_ON_ONCE(1);
+		header.id_time = 0;
+	}
+
+	header.id_time |= (u32)ctx->tsc & LTT_TSC_MASK;
+	lib_ring_buffer_write(config, ctx, &header, sizeof(header));
+
+	switch (ctx->rflags) {
+	case LTT_RFLAG_ID_SIZE_TSC:
+		small_size = (u16)min_t(u32, event_size, LTT_MAX_SMALL_SIZE);
+		lib_ring_buffer_write(config, ctx, &eID, sizeof(u16));
+		lib_ring_buffer_write(config, ctx, &small_size, sizeof(u16));
+		if (small_size == LTT_MAX_SMALL_SIZE)
+			lib_ring_buffer_write(config, ctx, &event_size,
+					      sizeof(u32));
+		lib_ring_buffer_align_ctx(ctx, sizeof(u64));
+		lib_ring_buffer_write(config, ctx, &ctx->tsc, sizeof(u64));
+		break;
+	case LTT_RFLAG_ID_SIZE:
+		small_size = (u16)min_t(u32, event_size, LTT_MAX_SMALL_SIZE);
+		lib_ring_buffer_write(config, ctx, &eID, sizeof(u16));
+		lib_ring_buffer_write(config, ctx, &small_size, sizeof(u16));
+		if (small_size == LTT_MAX_SMALL_SIZE)
+			lib_ring_buffer_write(config, ctx, &event_size,
+					      sizeof(u32));
+		break;
+	case LTT_RFLAG_ID:
+		lib_ring_buffer_write(config, ctx, &eID, sizeof(u16));
+		break;
+	}
+}
+
 static const struct lib_ring_buffer_config client_config;
 
 static u64 client_ring_buffer_clock_read(struct channel *chan)
@@ -53,10 +246,21 @@ static void client_buffer_begin(struct lib_ring_buffer *buf, u64 tsc,
 		(struct packet_header *)
 			lib_ring_buffer_offset_address(&buf->backend,
 				subbuf_idx * chan->backend.subbuf_size);
+	struct ltt_session *session = channel_get_private(chan);
 
+	header->magic = CTF_MAGIC_NUMBER;
+	memcpy(header->trace_uuid, session->uuid.b, sizeof(session->uuid));
 	header->timestamp_begin = tsc;
+	header->timestamp_end = 0;
 	header->content_size = 0xFFFFFFFF; /* for debugging */
-	write_trace_header(&client_config, header);
+	header->packet_size = 0xFFFFFFFF;
+	header->events_lost = 0;
+#if 0
+	header->start_time_sec = ltt_chan->session->start_time.tv_sec;
+	header->start_time_usec = ltt_chan->session->start_time.tv_usec;
+	header->start_freq = ltt_chan->session->start_freq;
+	header->freq_scale = ltt_chan->session->freq_scale;
+#endif //0
 }
 
 /*
@@ -73,9 +277,9 @@ static void client_buffer_end(struct lib_ring_buffer *buf, u64 tsc,
 				subbuf_idx * chan->backend.subbuf_size);
 	unsigned long records_lost = 0;
 
+	header->timestamp_end = tsc;
 	header->content_size = data_size;
 	header->packet_size = PAGE_ALIGN(data_size);
-	header->timestamp_end = tsc;
 	records_lost += lib_ring_buffer_get_records_lost_full(&client_config, buf);
 	records_lost += lib_ring_buffer_get_records_lost_wrap(&client_config, buf);
 	records_lost += lib_ring_buffer_get_records_lost_big(&client_config, buf);
@@ -151,6 +355,7 @@ void ltt_buffer_read_close(struct lib_ring_buffer *buf)
 	
 }
 
+static
 int ltt_event_reserve(struct lib_ring_buffer_ctx *ctx)
 {
 	int ret, cpu;
@@ -170,18 +375,26 @@ put:
 	return ret;
 }
 
+static
 void ltt_event_commit(struct lib_ring_buffer_ctx *ctx)
 {
 	lib_ring_buffer_commit(&client_config, ctx);
 	lib_ring_buffer_put_cpu(&client_config);
 }
 
+static
 void ltt_event_write(struct lib_ring_buffer_ctx *ctx, const void *src,
 		     size_t len)
 {
 	lib_ring_buffer_write(&client_config, ctx, src, len);
 }
 
+static
+wait_queue_head_t *ltt_get_reader_wait_queue(struct ltt_channel *chan)
+{
+	return &chan->chan->read_wait;
+}
+
 static struct ltt_transport ltt_relay_transport = {
 	.name = "relay-" RING_BUFFER_MODE_TEMPLATE_STRING,
 	.owner = THIS_MODULE,
@@ -193,11 +406,17 @@ static struct ltt_transport ltt_relay_transport = {
 		.event_reserve = ltt_event_reserve,
 		.event_commit = ltt_event_commit,
 		.event_write = ltt_event_write,
+		.get_reader_wait_queue = ltt_get_reader_wait_queue,
 	},
 };
 
 static int __init ltt_ring_buffer_client_init(void)
 {
+	/*
+	 * This vmalloc sync all also takes care of the lib ring buffer
+	 * vmalloc'd module pages when it is built as a module into LTTng.
+	 */
+	wrapper_vmalloc_sync_all();
 	printk(KERN_INFO "LTT : ltt ring buffer client init\n");
 	ltt_transport_register(&ltt_relay_transport);
 	return 0;