libust ABI: export streams

[lttng-ust.git] / libust / ltt-ring-buffer-client.h

diff --git a/libust/ltt-ring-buffer-client.h b/libust/ltt-ring-buffer-client.h
index dce34aa24597d35548069aa03e582cd2bbabf34b..605a28284e7e32c74664ff25190db46b7c7ddad5 100644 (file)
--- a/libust/ltt-ring-buffer-client.h
+++ b/libust/ltt-ring-buffer-client.h
@@ -293,13 +293,15 @@ static size_t client_packet_header_size(void)
 }
 
 static void client_buffer_begin(struct lib_ring_buffer *buf, u64 tsc,
-                               unsigned int subbuf_idx)
+                               unsigned int subbuf_idx,
+                               struct shm_handle *handle)
 {
-       struct channel *chan = shmp(buf->backend.chan);
+       struct channel *chan = shmp(handle, buf->backend.chan);
        struct packet_header *header =
                (struct packet_header *)
                        lib_ring_buffer_offset_address(&buf->backend,
-                               subbuf_idx * chan->backend.subbuf_size);
+                               subbuf_idx * chan->backend.subbuf_size,
+                               handle);
        struct ltt_channel *ltt_chan = channel_get_private(chan);
        struct ltt_session *session = ltt_chan->session;
 
@@ -319,31 +321,37 @@ static void client_buffer_begin(struct lib_ring_buffer *buf, u64 tsc,
  * subbuffer. data_size is between 1 and subbuf_size.
  */
 static void client_buffer_end(struct lib_ring_buffer *buf, u64 tsc,
-                             unsigned int subbuf_idx, unsigned long data_size)
+                             unsigned int subbuf_idx, unsigned long data_size,
+                             struct shm_handle *handle)
 {
-       struct channel *chan = shmp(buf->backend.chan);
+       struct channel *chan = shmp(handle, buf->backend.chan);
        struct packet_header *header =
                (struct packet_header *)
                        lib_ring_buffer_offset_address(&buf->backend,
-                               subbuf_idx * chan->backend.subbuf_size);
+                               subbuf_idx * chan->backend.subbuf_size,
+                               handle);
        unsigned long records_lost = 0;
 
        header->ctx.timestamp_end = tsc;
        header->ctx.content_size = data_size * CHAR_BIT;        /* in bits */
        header->ctx.packet_size = PAGE_ALIGN(data_size) * CHAR_BIT; /* in bits */
-       records_lost += lib_ring_buffer_get_records_lost_full(&client_config, buf);
+       /*
+        * We do not care about the records lost count, because the metadata
+        * channel waits and retry.
+        */
+       (void) 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);
        header->ctx.events_discarded = records_lost;
 }
 
 static int client_buffer_create(struct lib_ring_buffer *buf, void *priv,
-                               int cpu, const char *name)
+                               int cpu, const char *name, struct shm_handle *handle)
 {
        return 0;
 }
 
-static void client_buffer_finalize(struct lib_ring_buffer *buf, void *priv, int cpu)
+static void client_buffer_finalize(struct lib_ring_buffer *buf, void *priv, int cpu, struct shm_handle *handle)
 {
 }
 
@@ -358,51 +366,61 @@ static const struct lib_ring_buffer_config client_config = {
 
        .tsc_bits = 32,
        .alloc = RING_BUFFER_ALLOC_PER_CPU,
-       .sync = RING_BUFFER_SYNC_PER_CPU,
+       .sync = RING_BUFFER_SYNC_GLOBAL,
        .mode = RING_BUFFER_MODE_TEMPLATE,
        .backend = RING_BUFFER_PAGE,
-       .output = RING_BUFFER_SPLICE,
+       .output = RING_BUFFER_MMAP,
        .oops = RING_BUFFER_OOPS_CONSISTENCY,
-       .ipi = RING_BUFFER_IPI_BARRIER,
-       .wakeup = RING_BUFFER_WAKEUP_BY_TIMER,
+       .ipi = RING_BUFFER_NO_IPI_BARRIER,
+       .wakeup = RING_BUFFER_WAKEUP_BY_WRITER,
 };
 
 static
-struct shm_handle *_channel_create(const char *name,
+struct ltt_channel *_channel_create(const char *name,
                                struct ltt_channel *ltt_chan, void *buf_addr,
                                size_t subbuf_size, size_t num_subbuf,
                                unsigned int switch_timer_interval,
                                unsigned int read_timer_interval)
 {
-       return channel_create(&client_config, name, ltt_chan, buf_addr,
+       ltt_chan->handle = channel_create(&client_config, name, ltt_chan, buf_addr,
                              subbuf_size, num_subbuf, switch_timer_interval,
                              read_timer_interval);
+       if (!ltt_chan->handle)
+               return NULL;
+       ltt_chan->chan = shmp(ltt_chan->handle, ltt_chan->handle->chan);
+       return ltt_chan;
 }
 
 static
-void ltt_channel_destroy(struct shm_handle *handle)
+void ltt_channel_destroy(struct ltt_channel *ltt_chan)
 {
-       channel_destroy(handle);
+       channel_destroy(ltt_chan->chan, ltt_chan->handle);
 }
 
 static
-struct lib_ring_buffer *ltt_buffer_read_open(struct channel *chan)
+struct lib_ring_buffer *ltt_buffer_read_open(struct channel *chan,
+                                            struct shm_handle *handle,
+                                            int *shm_fd, int *wait_fd,
+                                            uint64_t *memory_map_size)
 {
        struct lib_ring_buffer *buf;
        int cpu;
 
        for_each_channel_cpu(cpu, chan) {
-               buf = channel_get_ring_buffer(&client_config, chan, cpu);
-               if (!lib_ring_buffer_open_read(buf))
+               buf = channel_get_ring_buffer(&client_config, chan,
+                               cpu, handle, shm_fd, wait_fd,
+                               memory_map_size);
+               if (!lib_ring_buffer_open_read(buf, handle))
                        return buf;
        }
        return NULL;
 }
 
 static
-void ltt_buffer_read_close(struct lib_ring_buffer *buf)
+void ltt_buffer_read_close(struct lib_ring_buffer *buf,
+                          struct shm_handle *handle)
 {
-       lib_ring_buffer_release_read(buf);
+       lib_ring_buffer_release_read(buf, handle);
 }
 
 static
@@ -481,7 +499,7 @@ int ltt_is_disabled(struct channel *chan)
 }
 
 static struct ltt_transport ltt_relay_transport = {
-       .name = "relay-" RING_BUFFER_MODE_TEMPLATE_STRING,
+       .name = "relay-" RING_BUFFER_MODE_TEMPLATE_STRING "-mmap",
        .ops = {
                .channel_create = _channel_create,
                .channel_destroy = ltt_channel_destroy,
@@ -498,16 +516,14 @@ static struct ltt_transport ltt_relay_transport = {
        },
 };
 
-static
-void __attribute__((constructor)) ltt_ring_buffer_client_init(void)
+void RING_BUFFER_MODE_TEMPLATE_INIT(void)
 {
-       printf("LTT : ltt ring buffer client init\n");
+       DBG("LTT : ltt ring buffer client init\n");
        ltt_transport_register(&ltt_relay_transport);
 }
 
-static
-void __attribute__((destructor)) ltt_ring_buffer_client_exit(void)
+void RING_BUFFER_MODE_TEMPLATE_EXIT(void)
 {
-       printf("LTT : ltt ring buffer client exit\n");
+       DBG("LTT : ltt ring buffer client exit\n");
        ltt_transport_unregister(&ltt_relay_transport);
 }