X-Git-Url: http://git.lttng.org/?p=lttng-modules.git;a=blobdiff_plain;f=lttng-ring-buffer-client.h;h=d5c512c5ccb8c372845541296fa8bafd48fb46b2;hp=c97793d2061a784b9ea68014a0c12cc9349c8bf6;hb=HEAD;hpb=537001624550a6e6c77d0e535b42d52a5e7c6719 diff --git a/lttng-ring-buffer-client.h b/lttng-ring-buffer-client.h deleted file mode 100644 index c97793d2..00000000 --- a/lttng-ring-buffer-client.h +++ /dev/null @@ -1,684 +0,0 @@ -/* - * lttng-ring-buffer-client.h - * - * LTTng lib ring buffer client template. - * - * Copyright (C) 2010-2012 Mathieu Desnoyers - * - * This library is free software; you can redistribute it and/or - * modify it under the terms of the GNU Lesser General Public - * License as published by the Free Software Foundation; only - * version 2.1 of the License. - * - * This library is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - * Lesser General Public License for more details. - * - * You should have received a copy of the GNU Lesser General Public - * License along with this library; if not, write to the Free Software - * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA - */ - -#include -#include -#include "lib/bitfield.h" -#include "wrapper/vmalloc.h" /* for wrapper_vmalloc_sync_all() */ -#include "wrapper/trace-clock.h" -#include "lttng-events.h" -#include "lttng-tracer.h" -#include "wrapper/ringbuffer/frontend_types.h" - -#define LTTNG_COMPACT_EVENT_BITS 5 -#define LTTNG_COMPACT_TSC_BITS 27 - -/* - * 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. - * - * The guarantee we have with timestamps is that all the events in a - * packet are included (inclusive) within the begin/end timestamps of - * the packet. Another guarantee we have is that the "timestamp begin", - * as well as the event timestamps, are monotonically increasing (never - * decrease) when moving forward in a stream (physically). But this - * guarantee does not apply to "timestamp end", because it is sampled at - * commit time, which is not ordered with respect to space reservation. - */ - -struct packet_header { - /* Trace packet header */ - uint32_t magic; /* - * Trace magic number. - * contains endianness information. - */ - uint8_t uuid[16]; - uint32_t stream_id; - - struct { - /* Stream packet context */ - uint64_t timestamp_begin; /* Cycle count at subbuffer start */ - uint64_t timestamp_end; /* Cycle count at subbuffer end */ - uint64_t content_size; /* Size of data in subbuffer */ - uint64_t packet_size; /* Subbuffer size (include padding) */ - unsigned long events_discarded; /* - * Events lost in this subbuffer since - * the beginning of the trace. - * (may overflow) - */ - uint32_t cpu_id; /* CPU id associated with stream */ - uint8_t header_end; /* End of header */ - } ctx; -}; - - -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 lttng_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 - * @chan: channel - * @offset: offset in the write buffer - * @pre_header_padding: padding to add before the header (output) - * @ctx: reservation context - * - * Returns the event header size (including padding). - * - * 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 *pre_header_padding, - struct lib_ring_buffer_ctx *ctx) -{ - struct lttng_channel *lttng_chan = channel_get_private(chan); - struct lttng_event *event = ctx->priv; - size_t orig_offset = offset; - size_t padding; - - switch (lttng_chan->header_type) { - case 1: /* compact */ - padding = lib_ring_buffer_align(offset, lttng_alignof(uint32_t)); - offset += padding; - if (!(ctx->rflags & (RING_BUFFER_RFLAG_FULL_TSC | LTTNG_RFLAG_EXTENDED))) { - offset += sizeof(uint32_t); /* id and timestamp */ - } else { - /* Minimum space taken by LTTNG_COMPACT_EVENT_BITS id */ - offset += (LTTNG_COMPACT_EVENT_BITS + CHAR_BIT - 1) / CHAR_BIT; - /* Align extended struct on largest member */ - offset += lib_ring_buffer_align(offset, lttng_alignof(uint64_t)); - offset += sizeof(uint32_t); /* id */ - offset += lib_ring_buffer_align(offset, lttng_alignof(uint64_t)); - offset += sizeof(uint64_t); /* timestamp */ - } - break; - case 2: /* large */ - padding = lib_ring_buffer_align(offset, lttng_alignof(uint16_t)); - offset += padding; - offset += sizeof(uint16_t); - if (!(ctx->rflags & (RING_BUFFER_RFLAG_FULL_TSC | LTTNG_RFLAG_EXTENDED))) { - offset += lib_ring_buffer_align(offset, lttng_alignof(uint32_t)); - offset += sizeof(uint32_t); /* timestamp */ - } else { - /* Align extended struct on largest member */ - offset += lib_ring_buffer_align(offset, lttng_alignof(uint64_t)); - offset += sizeof(uint32_t); /* id */ - offset += lib_ring_buffer_align(offset, lttng_alignof(uint64_t)); - offset += sizeof(uint64_t); /* timestamp */ - } - break; - default: - padding = 0; - WARN_ON_ONCE(1); - } - offset += ctx_get_size(offset, event->ctx); - offset += ctx_get_size(offset, lttng_chan->ctx); - - *pre_header_padding = padding; - return offset - orig_offset; -} - -#include "wrapper/ringbuffer/api.h" - -static -void lttng_write_event_header_slow(const struct lib_ring_buffer_config *config, - struct lib_ring_buffer_ctx *ctx, - uint32_t event_id); - -/* - * lttng_write_event_header - * - * Writes the event header to the offset (already aligned on 32-bits). - * - * @config: ring buffer instance configuration - * @ctx: reservation context - * @event_id: event ID - */ -static __inline__ -void lttng_write_event_header(const struct lib_ring_buffer_config *config, - struct lib_ring_buffer_ctx *ctx, - uint32_t event_id) -{ - struct lttng_channel *lttng_chan = channel_get_private(ctx->chan); - struct lttng_event *event = ctx->priv; - - if (unlikely(ctx->rflags)) - goto slow_path; - - switch (lttng_chan->header_type) { - case 1: /* compact */ - { - uint32_t id_time = 0; - - bt_bitfield_write(&id_time, uint32_t, - 0, - LTTNG_COMPACT_EVENT_BITS, - event_id); - bt_bitfield_write(&id_time, uint32_t, - LTTNG_COMPACT_EVENT_BITS, - LTTNG_COMPACT_TSC_BITS, - ctx->tsc); - lib_ring_buffer_write(config, ctx, &id_time, sizeof(id_time)); - break; - } - case 2: /* large */ - { - uint32_t timestamp = (uint32_t) ctx->tsc; - uint16_t id = event_id; - - lib_ring_buffer_write(config, ctx, &id, sizeof(id)); - lib_ring_buffer_align_ctx(ctx, lttng_alignof(uint32_t)); - lib_ring_buffer_write(config, ctx, ×tamp, sizeof(timestamp)); - break; - } - default: - WARN_ON_ONCE(1); - } - - ctx_record(ctx, lttng_chan, lttng_chan->ctx); - ctx_record(ctx, lttng_chan, event->ctx); - lib_ring_buffer_align_ctx(ctx, ctx->largest_align); - - return; - -slow_path: - lttng_write_event_header_slow(config, ctx, event_id); -} - -static -void lttng_write_event_header_slow(const struct lib_ring_buffer_config *config, - struct lib_ring_buffer_ctx *ctx, - uint32_t event_id) -{ - struct lttng_channel *lttng_chan = channel_get_private(ctx->chan); - struct lttng_event *event = ctx->priv; - - switch (lttng_chan->header_type) { - case 1: /* compact */ - if (!(ctx->rflags & (RING_BUFFER_RFLAG_FULL_TSC | LTTNG_RFLAG_EXTENDED))) { - uint32_t id_time = 0; - - bt_bitfield_write(&id_time, uint32_t, - 0, - LTTNG_COMPACT_EVENT_BITS, - event_id); - bt_bitfield_write(&id_time, uint32_t, - LTTNG_COMPACT_EVENT_BITS, - LTTNG_COMPACT_TSC_BITS, ctx->tsc); - lib_ring_buffer_write(config, ctx, &id_time, sizeof(id_time)); - } else { - uint8_t id = 0; - uint64_t timestamp = ctx->tsc; - - bt_bitfield_write(&id, uint8_t, - 0, - LTTNG_COMPACT_EVENT_BITS, - 31); - lib_ring_buffer_write(config, ctx, &id, sizeof(id)); - /* Align extended struct on largest member */ - lib_ring_buffer_align_ctx(ctx, lttng_alignof(uint64_t)); - lib_ring_buffer_write(config, ctx, &event_id, sizeof(event_id)); - lib_ring_buffer_align_ctx(ctx, lttng_alignof(uint64_t)); - lib_ring_buffer_write(config, ctx, ×tamp, sizeof(timestamp)); - } - break; - case 2: /* large */ - { - if (!(ctx->rflags & (RING_BUFFER_RFLAG_FULL_TSC | LTTNG_RFLAG_EXTENDED))) { - uint32_t timestamp = (uint32_t) ctx->tsc; - uint16_t id = event_id; - - lib_ring_buffer_write(config, ctx, &id, sizeof(id)); - lib_ring_buffer_align_ctx(ctx, lttng_alignof(uint32_t)); - lib_ring_buffer_write(config, ctx, ×tamp, sizeof(timestamp)); - } else { - uint16_t id = 65535; - uint64_t timestamp = ctx->tsc; - - lib_ring_buffer_write(config, ctx, &id, sizeof(id)); - /* Align extended struct on largest member */ - lib_ring_buffer_align_ctx(ctx, lttng_alignof(uint64_t)); - lib_ring_buffer_write(config, ctx, &event_id, sizeof(event_id)); - lib_ring_buffer_align_ctx(ctx, lttng_alignof(uint64_t)); - lib_ring_buffer_write(config, ctx, ×tamp, sizeof(timestamp)); - } - break; - } - default: - WARN_ON_ONCE(1); - } - ctx_record(ctx, lttng_chan, lttng_chan->ctx); - ctx_record(ctx, lttng_chan, event->ctx); - lib_ring_buffer_align_ctx(ctx, ctx->largest_align); -} - -static const struct lib_ring_buffer_config client_config; - -static u64 client_ring_buffer_clock_read(struct channel *chan) -{ - return lib_ring_buffer_clock_read(chan); -} - -static -size_t client_record_header_size(const struct lib_ring_buffer_config *config, - struct channel *chan, size_t offset, - size_t *pre_header_padding, - struct lib_ring_buffer_ctx *ctx) -{ - return record_header_size(config, chan, offset, - pre_header_padding, ctx); -} - -/** - * 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 packet_header, ctx.header_end); -} - -static void client_buffer_begin(struct lib_ring_buffer *buf, u64 tsc, - unsigned int subbuf_idx) -{ - struct channel *chan = buf->backend.chan; - struct packet_header *header = - (struct packet_header *) - lib_ring_buffer_offset_address(&buf->backend, - subbuf_idx * chan->backend.subbuf_size); - struct lttng_channel *lttng_chan = channel_get_private(chan); - struct lttng_session *session = lttng_chan->session; - - header->magic = CTF_MAGIC_NUMBER; - memcpy(header->uuid, session->uuid.b, sizeof(session->uuid)); - header->stream_id = lttng_chan->id; - header->ctx.timestamp_begin = tsc; - header->ctx.timestamp_end = 0; - header->ctx.content_size = ~0ULL; /* for debugging */ - header->ctx.packet_size = ~0ULL; - header->ctx.events_discarded = 0; - header->ctx.cpu_id = buf->backend.cpu; -} - -/* - * 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 lib_ring_buffer *buf, u64 tsc, - unsigned int subbuf_idx, unsigned long data_size) -{ - struct channel *chan = buf->backend.chan; - struct packet_header *header = - (struct packet_header *) - lib_ring_buffer_offset_address(&buf->backend, - subbuf_idx * chan->backend.subbuf_size); - unsigned long records_lost = 0; - - header->ctx.timestamp_end = tsc; - header->ctx.content_size = - (uint64_t) data_size * CHAR_BIT; /* in bits */ - header->ctx.packet_size = - (uint64_t) PAGE_ALIGN(data_size) * CHAR_BIT; /* in bits */ - 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); - header->ctx.events_discarded = records_lost; -} - -static int client_buffer_create(struct lib_ring_buffer *buf, void *priv, - int cpu, const char *name) -{ - return 0; -} - -static void client_buffer_finalize(struct lib_ring_buffer *buf, void *priv, int cpu) -{ -} - -static struct packet_header *client_packet_header( - const struct lib_ring_buffer_config *config, - struct lib_ring_buffer *buf) -{ - return lib_ring_buffer_read_offset_address(&buf->backend, 0); -} - -static int client_timestamp_begin(const struct lib_ring_buffer_config *config, - struct lib_ring_buffer *buf, - uint64_t *timestamp_begin) -{ - struct packet_header *header = client_packet_header(config, buf); - *timestamp_begin = header->ctx.timestamp_begin; - - return 0; -} - -static int client_timestamp_end(const struct lib_ring_buffer_config *config, - struct lib_ring_buffer *buf, - uint64_t *timestamp_end) -{ - struct packet_header *header = client_packet_header(config, buf); - *timestamp_end = header->ctx.timestamp_end; - - return 0; -} - -static int client_events_discarded(const struct lib_ring_buffer_config *config, - struct lib_ring_buffer *buf, - uint64_t *events_discarded) -{ - struct packet_header *header = client_packet_header(config, buf); - *events_discarded = header->ctx.events_discarded; - - return 0; -} - -static int client_content_size(const struct lib_ring_buffer_config *config, - struct lib_ring_buffer *buf, - uint64_t *content_size) -{ - struct packet_header *header = client_packet_header(config, buf); - *content_size = header->ctx.content_size; - - return 0; -} - -static int client_packet_size(const struct lib_ring_buffer_config *config, - struct lib_ring_buffer *buf, - uint64_t *packet_size) -{ - struct packet_header *header = client_packet_header(config, buf); - *packet_size = header->ctx.packet_size; - - return 0; -} - -static int client_stream_id(const struct lib_ring_buffer_config *config, - struct lib_ring_buffer *buf, - uint64_t *stream_id) -{ - struct packet_header *header = client_packet_header(config, buf); - *stream_id = header->stream_id; - - return 0; -} - -static int client_current_timestamp(const struct lib_ring_buffer_config *config, - struct lib_ring_buffer *bufb, - uint64_t *ts) -{ - *ts = config->cb.ring_buffer_clock_read(bufb->backend.chan); - - return 0; -} - -static const struct 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 = LTTNG_COMPACT_TSC_BITS, - .alloc = RING_BUFFER_ALLOC_PER_CPU, - .sync = RING_BUFFER_SYNC_PER_CPU, - .mode = RING_BUFFER_MODE_TEMPLATE, - .backend = RING_BUFFER_PAGE, - .output = RING_BUFFER_OUTPUT_TEMPLATE, - .oops = RING_BUFFER_OOPS_CONSISTENCY, - .ipi = RING_BUFFER_IPI_BARRIER, - .wakeup = RING_BUFFER_WAKEUP_BY_TIMER, -}; - -static -struct channel *_channel_create(const char *name, - struct lttng_channel *lttng_chan, void *buf_addr, - size_t subbuf_size, size_t num_subbuf, - unsigned int switch_timer_interval, - unsigned int read_timer_interval) -{ - lttng_chan->ops->timestamp_begin = client_timestamp_begin; - lttng_chan->ops->timestamp_end = client_timestamp_end; - lttng_chan->ops->events_discarded = client_events_discarded; - lttng_chan->ops->content_size = client_content_size; - lttng_chan->ops->packet_size = client_packet_size; - lttng_chan->ops->stream_id = client_stream_id; - lttng_chan->ops->current_timestamp = client_current_timestamp; - - return channel_create(&client_config, name, lttng_chan, buf_addr, - subbuf_size, num_subbuf, switch_timer_interval, - read_timer_interval); -} - -static -void lttng_channel_destroy(struct channel *chan) -{ - channel_destroy(chan); -} - -static -struct lib_ring_buffer *lttng_buffer_read_open(struct channel *chan) -{ - 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)) - return buf; - } - return NULL; -} - -static -int lttng_buffer_has_read_closed_stream(struct channel *chan) -{ - struct lib_ring_buffer *buf; - int cpu; - - for_each_channel_cpu(cpu, chan) { - buf = channel_get_ring_buffer(&client_config, chan, cpu); - if (!atomic_long_read(&buf->active_readers)) - return 1; - } - return 0; -} - -static -void lttng_buffer_read_close(struct lib_ring_buffer *buf) -{ - lib_ring_buffer_release_read(buf); -} - -static -int lttng_event_reserve(struct lib_ring_buffer_ctx *ctx, - uint32_t event_id) -{ - struct lttng_channel *lttng_chan = channel_get_private(ctx->chan); - int ret, cpu; - - cpu = lib_ring_buffer_get_cpu(&client_config); - if (cpu < 0) - return -EPERM; - ctx->cpu = cpu; - - switch (lttng_chan->header_type) { - case 1: /* compact */ - if (event_id > 30) - ctx->rflags |= LTTNG_RFLAG_EXTENDED; - break; - case 2: /* large */ - if (event_id > 65534) - ctx->rflags |= LTTNG_RFLAG_EXTENDED; - break; - default: - WARN_ON_ONCE(1); - } - - ret = lib_ring_buffer_reserve(&client_config, ctx); - if (ret) - goto put; - lttng_write_event_header(&client_config, ctx, event_id); - return 0; -put: - lib_ring_buffer_put_cpu(&client_config); - return ret; -} - -static -void lttng_event_commit(struct lib_ring_buffer_ctx *ctx) -{ - lib_ring_buffer_commit(&client_config, ctx); - lib_ring_buffer_put_cpu(&client_config); -} - -static -void lttng_event_write(struct lib_ring_buffer_ctx *ctx, const void *src, - size_t len) -{ - lib_ring_buffer_write(&client_config, ctx, src, len); -} - -static -void lttng_event_write_from_user(struct lib_ring_buffer_ctx *ctx, - const void __user *src, size_t len) -{ - lib_ring_buffer_copy_from_user_inatomic(&client_config, ctx, src, len); -} - -static -void lttng_event_memset(struct lib_ring_buffer_ctx *ctx, - int c, size_t len) -{ - lib_ring_buffer_memset(&client_config, ctx, c, len); -} - -static -wait_queue_head_t *lttng_get_writer_buf_wait_queue(struct channel *chan, int cpu) -{ - struct lib_ring_buffer *buf = channel_get_ring_buffer(&client_config, - chan, cpu); - return &buf->write_wait; -} - -static -wait_queue_head_t *lttng_get_hp_wait_queue(struct channel *chan) -{ - return &chan->hp_wait; -} - -static -int lttng_is_finalized(struct channel *chan) -{ - return lib_ring_buffer_channel_is_finalized(chan); -} - -static -int lttng_is_disabled(struct channel *chan) -{ - return lib_ring_buffer_channel_is_disabled(chan); -} - -static struct lttng_transport lttng_relay_transport = { - .name = "relay-" RING_BUFFER_MODE_TEMPLATE_STRING, - .owner = THIS_MODULE, - .ops = { - .channel_create = _channel_create, - .channel_destroy = lttng_channel_destroy, - .buffer_read_open = lttng_buffer_read_open, - .buffer_has_read_closed_stream = - lttng_buffer_has_read_closed_stream, - .buffer_read_close = lttng_buffer_read_close, - .event_reserve = lttng_event_reserve, - .event_commit = lttng_event_commit, - .event_write = lttng_event_write, - .event_write_from_user = lttng_event_write_from_user, - .event_memset = lttng_event_memset, - .packet_avail_size = NULL, /* Would be racy anyway */ - .get_writer_buf_wait_queue = lttng_get_writer_buf_wait_queue, - .get_hp_wait_queue = lttng_get_hp_wait_queue, - .is_finalized = lttng_is_finalized, - .is_disabled = lttng_is_disabled, - }, -}; - -static int __init lttng_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(); - lttng_transport_register(<tng_relay_transport); - return 0; -} - -module_init(lttng_ring_buffer_client_init); - -static void __exit lttng_ring_buffer_client_exit(void) -{ - lttng_transport_unregister(<tng_relay_transport); -} - -module_exit(lttng_ring_buffer_client_exit); - -MODULE_LICENSE("GPL and additional rights"); -MODULE_AUTHOR("Mathieu Desnoyers"); -MODULE_DESCRIPTION("LTTng ring buffer " RING_BUFFER_MODE_TEMPLATE_STRING - " client");