X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=liblttng-ust%2Flttng-ring-buffer-metadata-client-template.h;fp=liblttng-ust%2Flttng-ring-buffer-metadata-client-template.h;h=f4d1362a6e9b95303349483a574842815a96ed77;hb=c53279a3e7796da67c5ad8d5e5657bf03def2dcb;hp=0000000000000000000000000000000000000000;hpb=74c3f8e27f5b750b71136ce1737972c28f288540;p=lttng-ust.git diff --git a/liblttng-ust/lttng-ring-buffer-metadata-client-template.h b/liblttng-ust/lttng-ring-buffer-metadata-client-template.h new file mode 100644 index 00000000..f4d1362a --- /dev/null +++ b/liblttng-ust/lttng-ring-buffer-metadata-client-template.h @@ -0,0 +1,360 @@ +/* + * SPDX-License-Identifier: LGPL-2.1-only + * + * Copyright (C) 2010-2012 Mathieu Desnoyers + * + * LTTng lib ring buffer client template. + */ + +#include +#include +#include + +#include +#include "ust-bitfield.h" +#include "ust-compat.h" +#include "lttng-tracer.h" +#include "../libringbuffer/frontend_types.h" +#include + +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); +}