--- /dev/null
+/*
+ * SPDX-License-Identifier: LGPL-2.1-only
+ *
+ * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ *
+ * LTTng lib ring buffer client template.
+ */
+
+#include <limits.h>
+#include <stddef.h>
+#include <stdint.h>
+
+#include <ust-events-internal.h>
+#include "ust-bitfield.h"
+#include "ust-compat.h"
+#include "lttng-tracer.h"
+#include "../libringbuffer/frontend_types.h"
+#include <urcu/tls-compat.h>
+
+struct metadata_packet_header {
+ uint32_t magic; /* 0x75D11D57 */
+ uint8_t uuid[LTTNG_UST_UUID_LEN]; /* Unique Universal Identifier */
+ uint32_t checksum; /* 0 if unused */
+ uint32_t content_size; /* in bits */
+ uint32_t packet_size; /* in bits */
+ uint8_t compression_scheme; /* 0 if unused */
+ uint8_t encryption_scheme; /* 0 if unused */
+ uint8_t checksum_scheme; /* 0 if unused */
+ uint8_t major; /* CTF spec major version number */
+ uint8_t minor; /* CTF spec minor version number */
+ uint8_t header_end[0];
+};
+
+struct metadata_record_header {
+ uint8_t header_end[0]; /* End of header */
+};
+
+static const struct lttng_ust_lib_ring_buffer_config client_config;
+
+/* No nested use supported for metadata ring buffer. */
+static DEFINE_URCU_TLS(struct lttng_ust_lib_ring_buffer_ctx_private, private_ctx);
+
+static inline uint64_t lib_ring_buffer_clock_read(struct lttng_ust_lib_ring_buffer_channel *chan)
+{
+ return 0;
+}
+
+static inline
+size_t record_header_size(const struct lttng_ust_lib_ring_buffer_config *config,
+ struct lttng_ust_lib_ring_buffer_channel *chan,
+ size_t offset,
+ size_t *pre_header_padding,
+ struct lttng_ust_lib_ring_buffer_ctx *ctx,
+ void *client_ctx)
+{
+ return 0;
+}
+
+#include "../libringbuffer/api.h"
+#include "lttng-rb-clients.h"
+
+static uint64_t client_ring_buffer_clock_read(struct lttng_ust_lib_ring_buffer_channel *chan)
+{
+ return 0;
+}
+
+static
+size_t client_record_header_size(const struct lttng_ust_lib_ring_buffer_config *config,
+ struct lttng_ust_lib_ring_buffer_channel *chan,
+ size_t offset,
+ size_t *pre_header_padding,
+ struct lttng_ust_lib_ring_buffer_ctx *ctx,
+ void *client_ctx)
+{
+ return 0;
+}
+
+/**
+ * client_packet_header_size - called on buffer-switch to a new sub-buffer
+ *
+ * Return header size without padding after the structure. Don't use packed
+ * structure because gcc generates inefficient code on some architectures
+ * (powerpc, mips..)
+ */
+static size_t client_packet_header_size(void)
+{
+ return offsetof(struct metadata_packet_header, header_end);
+}
+
+static void client_buffer_begin(struct lttng_ust_lib_ring_buffer *buf, uint64_t tsc,
+ unsigned int subbuf_idx,
+ struct lttng_ust_shm_handle *handle)
+{
+ struct lttng_ust_lib_ring_buffer_channel *chan = shmp(handle, buf->backend.chan);
+ struct metadata_packet_header *header =
+ (struct metadata_packet_header *)
+ lib_ring_buffer_offset_address(&buf->backend,
+ subbuf_idx * chan->backend.subbuf_size,
+ handle);
+ struct lttng_ust_channel_buffer *lttng_chan = channel_get_private(chan);
+
+ assert(header);
+ if (!header)
+ return;
+ header->magic = TSDL_MAGIC_NUMBER;
+ memcpy(header->uuid, lttng_chan->priv->uuid, sizeof(lttng_chan->priv->uuid));
+ header->checksum = 0; /* 0 if unused */
+ header->content_size = 0xFFFFFFFF; /* in bits, for debugging */
+ header->packet_size = 0xFFFFFFFF; /* in bits, for debugging */
+ header->compression_scheme = 0; /* 0 if unused */
+ header->encryption_scheme = 0; /* 0 if unused */
+ header->checksum_scheme = 0; /* 0 if unused */
+ header->major = CTF_SPEC_MAJOR;
+ header->minor = CTF_SPEC_MINOR;
+}
+
+/*
+ * offset is assumed to never be 0 here : never deliver a completely empty
+ * subbuffer. data_size is between 1 and subbuf_size.
+ */
+static void client_buffer_end(struct lttng_ust_lib_ring_buffer *buf, uint64_t tsc,
+ unsigned int subbuf_idx, unsigned long data_size,
+ struct lttng_ust_shm_handle *handle)
+{
+ struct lttng_ust_lib_ring_buffer_channel *chan = shmp(handle, buf->backend.chan);
+ struct metadata_packet_header *header =
+ (struct metadata_packet_header *)
+ lib_ring_buffer_offset_address(&buf->backend,
+ subbuf_idx * chan->backend.subbuf_size,
+ handle);
+ unsigned long records_lost = 0;
+
+ assert(header);
+ if (!header)
+ return;
+ header->content_size = data_size * CHAR_BIT; /* in bits */
+ header->packet_size = LTTNG_UST_PAGE_ALIGN(data_size) * CHAR_BIT; /* in bits */
+ /*
+ * 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);
+ WARN_ON_ONCE(records_lost != 0);
+}
+
+static int client_buffer_create(struct lttng_ust_lib_ring_buffer *buf, void *priv,
+ int cpu, const char *name,
+ struct lttng_ust_shm_handle *handle)
+{
+ return 0;
+}
+
+static void client_buffer_finalize(struct lttng_ust_lib_ring_buffer *buf,
+ void *priv, int cpu,
+ struct lttng_ust_shm_handle *handle)
+{
+}
+
+static const
+struct lttng_ust_client_lib_ring_buffer_client_cb client_cb = {
+ .parent = {
+ .ring_buffer_clock_read = client_ring_buffer_clock_read,
+ .record_header_size = client_record_header_size,
+ .subbuffer_header_size = client_packet_header_size,
+ .buffer_begin = client_buffer_begin,
+ .buffer_end = client_buffer_end,
+ .buffer_create = client_buffer_create,
+ .buffer_finalize = client_buffer_finalize,
+ },
+};
+
+static const struct lttng_ust_lib_ring_buffer_config client_config = {
+ .cb.ring_buffer_clock_read = client_ring_buffer_clock_read,
+ .cb.record_header_size = client_record_header_size,
+ .cb.subbuffer_header_size = client_packet_header_size,
+ .cb.buffer_begin = client_buffer_begin,
+ .cb.buffer_end = client_buffer_end,
+ .cb.buffer_create = client_buffer_create,
+ .cb.buffer_finalize = client_buffer_finalize,
+
+ .tsc_bits = 0,
+ .alloc = RING_BUFFER_ALLOC_GLOBAL,
+ .sync = RING_BUFFER_SYNC_GLOBAL,
+ .mode = RING_BUFFER_MODE_TEMPLATE,
+ .backend = RING_BUFFER_PAGE,
+ .output = RING_BUFFER_MMAP,
+ .oops = RING_BUFFER_OOPS_CONSISTENCY,
+ .ipi = RING_BUFFER_NO_IPI_BARRIER,
+ .wakeup = RING_BUFFER_WAKEUP_BY_WRITER,
+ .client_type = LTTNG_CLIENT_TYPE,
+
+ .cb_ptr = &client_cb.parent,
+};
+
+static
+struct lttng_ust_channel_buffer *_channel_create(const char *name,
+ void *buf_addr,
+ size_t subbuf_size, size_t num_subbuf,
+ unsigned int switch_timer_interval,
+ unsigned int read_timer_interval,
+ unsigned char *uuid,
+ uint32_t chan_id,
+ const int *stream_fds, int nr_stream_fds,
+ int64_t blocking_timeout)
+{
+ struct lttng_ust_abi_channel_config chan_priv_init;
+ struct lttng_ust_shm_handle *handle;
+ struct lttng_ust_channel_buffer *lttng_chan_buf;
+
+ lttng_chan_buf = lttng_ust_alloc_channel_buffer();
+ if (!lttng_chan_buf)
+ return NULL;
+ memcpy(lttng_chan_buf->priv->uuid, uuid, LTTNG_UST_UUID_LEN);
+ lttng_chan_buf->priv->id = chan_id;
+
+ memset(&chan_priv_init, 0, sizeof(chan_priv_init));
+ memcpy(chan_priv_init.uuid, uuid, LTTNG_UST_UUID_LEN);
+ chan_priv_init.id = chan_id;
+
+ handle = channel_create(&client_config, name,
+ __alignof__(struct lttng_ust_channel_buffer),
+ sizeof(struct lttng_ust_channel_buffer),
+ &chan_priv_init,
+ lttng_chan_buf, buf_addr, subbuf_size, num_subbuf,
+ switch_timer_interval, read_timer_interval,
+ stream_fds, nr_stream_fds, blocking_timeout);
+ if (!handle)
+ goto error;
+ lttng_chan_buf->priv->rb_chan = shmp(handle, handle->chan);
+ return lttng_chan_buf;
+
+error:
+ lttng_ust_free_channel_common(lttng_chan_buf->parent);
+ return NULL;
+}
+
+static
+void lttng_channel_destroy(struct lttng_ust_channel_buffer *lttng_chan_buf)
+{
+ channel_destroy(lttng_chan_buf->priv->rb_chan, lttng_chan_buf->priv->rb_chan->handle, 1);
+ lttng_ust_free_channel_common(lttng_chan_buf->parent);
+}
+
+static
+int lttng_event_reserve(struct lttng_ust_lib_ring_buffer_ctx *ctx)
+{
+ int ret;
+
+ memset(&URCU_TLS(private_ctx), 0, sizeof(struct lttng_ust_lib_ring_buffer_ctx_private));
+ URCU_TLS(private_ctx).pub = ctx;
+ URCU_TLS(private_ctx).chan = ctx->client_priv;
+ ctx->priv = &URCU_TLS(private_ctx);
+ ret = lib_ring_buffer_reserve(&client_config, ctx, NULL);
+ if (ret)
+ return ret;
+ if (lib_ring_buffer_backend_get_pages(&client_config, ctx,
+ &ctx->priv->backend_pages))
+ return -EPERM;
+ return 0;
+}
+
+static
+void lttng_event_commit(struct lttng_ust_lib_ring_buffer_ctx *ctx)
+{
+ lib_ring_buffer_commit(&client_config, ctx);
+}
+
+static
+void lttng_event_write(struct lttng_ust_lib_ring_buffer_ctx *ctx,
+ const void *src, size_t len, size_t alignment)
+{
+ lttng_ust_lib_ring_buffer_align_ctx(ctx, alignment);
+ lib_ring_buffer_write(&client_config, ctx, src, len);
+}
+
+static
+size_t lttng_packet_avail_size(struct lttng_ust_channel_buffer *chan)
+{
+ struct lttng_ust_lib_ring_buffer_channel *rb_chan = chan->priv->rb_chan;
+ unsigned long o_begin;
+ struct lttng_ust_lib_ring_buffer *buf;
+
+ buf = shmp(rb_chan->handle, rb_chan->backend.buf[0].shmp); /* Only for global buffer ! */
+ o_begin = v_read(&client_config, &buf->offset);
+ if (subbuf_offset(o_begin, rb_chan) != 0) {
+ return rb_chan->backend.subbuf_size - subbuf_offset(o_begin, rb_chan);
+ } else {
+ return rb_chan->backend.subbuf_size - subbuf_offset(o_begin, rb_chan)
+ - sizeof(struct metadata_packet_header);
+ }
+}
+
+static
+int lttng_is_finalized(struct lttng_ust_channel_buffer *chan)
+{
+ struct lttng_ust_lib_ring_buffer_channel *rb_chan = chan->priv->rb_chan;
+
+ return lib_ring_buffer_channel_is_finalized(rb_chan);
+}
+
+static
+int lttng_is_disabled(struct lttng_ust_channel_buffer *chan)
+{
+ struct lttng_ust_lib_ring_buffer_channel *rb_chan = chan->priv->rb_chan;
+
+ return lib_ring_buffer_channel_is_disabled(rb_chan);
+}
+
+static
+int lttng_flush_buffer(struct lttng_ust_channel_buffer *chan)
+{
+ struct lttng_ust_lib_ring_buffer_channel *rb_chan = chan->priv->rb_chan;
+ struct lttng_ust_lib_ring_buffer *buf;
+ int shm_fd, wait_fd, wakeup_fd;
+ uint64_t memory_map_size;
+
+ buf = channel_get_ring_buffer(&client_config, rb_chan,
+ 0, rb_chan->handle, &shm_fd, &wait_fd, &wakeup_fd,
+ &memory_map_size);
+ lib_ring_buffer_switch(&client_config, buf,
+ SWITCH_ACTIVE, rb_chan->handle);
+ return 0;
+}
+
+static struct lttng_transport lttng_relay_transport = {
+ .name = "relay-" RING_BUFFER_MODE_TEMPLATE_STRING "-mmap",
+ .ops = {
+ .struct_size = sizeof(struct lttng_ust_channel_buffer_ops),
+
+ .priv = __LTTNG_COMPOUND_LITERAL(struct lttng_ust_channel_buffer_ops_private, {
+ .pub = <tng_relay_transport.ops,
+ .channel_create = _channel_create,
+ .channel_destroy = lttng_channel_destroy,
+ .packet_avail_size = lttng_packet_avail_size,
+ .is_finalized = lttng_is_finalized,
+ .is_disabled = lttng_is_disabled,
+ .flush_buffer = lttng_flush_buffer,
+ }),
+ .event_reserve = lttng_event_reserve,
+ .event_commit = lttng_event_commit,
+ .event_write = lttng_event_write,
+ },
+ .client_config = &client_config,
+};
+
+void RING_BUFFER_MODE_TEMPLATE_INIT(void)
+{
+ DBG("LTT : ltt ring buffer client \"%s\" init\n",
+ "relay-" RING_BUFFER_MODE_TEMPLATE_STRING "-mmap");
+ lttng_transport_register(<tng_relay_transport);
+}
+
+void RING_BUFFER_MODE_TEMPLATE_EXIT(void)
+{
+ DBG("LTT : ltt ring buffer client \"%s\" exit\n",
+ "relay-" RING_BUFFER_MODE_TEMPLATE_STRING "-mmap");
+ lttng_transport_unregister(<tng_relay_transport);
+}
projects / lttng-ust.git / blobdiff