--- /dev/null
+/*
+ * Copyright (C) 2011 - Julien Desfossez <julien.desfossez@polymtl.ca>
+ * Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; only version 2
+ * of the License.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#define _GNU_SOURCE
+#include <assert.h>
+#include <fcntl.h>
+#include <poll.h>
+#include <pthread.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/mman.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <lttng/ust-ctl.h>
+
+#include <common/lttngerr.h>
+#include <common/runas.h>
+#include <common/sessiond-comm/sessiond-comm.h>
+
+#include "ust-consumer.h"
+
+extern struct lttng_consumer_global_data consumer_data;
+extern int consumer_poll_timeout;
+extern volatile int consumer_quit;
+
+/*
+ * Mmap the ring buffer, read it and write the data to the tracefile.
+ *
+ * Returns the number of bytes written
+ */
+int lttng_ustconsumer_on_read_subbuffer_mmap(
+ struct lttng_consumer_local_data *ctx,
+ struct lttng_consumer_stream *stream, unsigned long len)
+{
+ unsigned long mmap_offset;
+ long ret = 0;
+ off_t orig_offset = stream->out_fd_offset;
+ int outfd = stream->out_fd;
+
+ /* get the offset inside the fd to mmap */
+ ret = ustctl_get_mmap_read_offset(stream->chan->handle,
+ stream->buf, &mmap_offset);
+ if (ret != 0) {
+ ret = -errno;
+ perror("ustctl_get_mmap_read_offset");
+ goto end;
+ }
+ while (len > 0) {
+ ret = write(outfd, stream->mmap_base + mmap_offset, len);
+ if (ret >= len) {
+ len = 0;
+ } else if (ret < 0) {
+ ret = -errno;
+ perror("Error in file write");
+ goto end;
+ }
+ /* This won't block, but will start writeout asynchronously */
+ sync_file_range(outfd, stream->out_fd_offset, ret,
+ SYNC_FILE_RANGE_WRITE);
+ stream->out_fd_offset += ret;
+ }
+
+ lttng_consumer_sync_trace_file(stream, orig_offset);
+
+ goto end;
+
+end:
+ return ret;
+}
+
+/*
+ * Splice the data from the ring buffer to the tracefile.
+ *
+ * Returns the number of bytes spliced.
+ */
+int lttng_ustconsumer_on_read_subbuffer_splice(
+ struct lttng_consumer_local_data *ctx,
+ struct lttng_consumer_stream *stream, unsigned long len)
+{
+ return -ENOSYS;
+}
+
+/*
+ * Take a snapshot for a specific fd
+ *
+ * Returns 0 on success, < 0 on error
+ */
+int lttng_ustconsumer_take_snapshot(struct lttng_consumer_local_data *ctx,
+ struct lttng_consumer_stream *stream)
+{
+ int ret = 0;
+
+ ret = ustctl_snapshot(stream->chan->handle, stream->buf);
+ if (ret != 0) {
+ ret = errno;
+ perror("Getting sub-buffer snapshot.");
+ }
+
+ return ret;
+}
+
+/*
+ * Get the produced position
+ *
+ * Returns 0 on success, < 0 on error
+ */
+int lttng_ustconsumer_get_produced_snapshot(
+ struct lttng_consumer_local_data *ctx,
+ struct lttng_consumer_stream *stream,
+ unsigned long *pos)
+{
+ int ret;
+
+ ret = ustctl_snapshot_get_produced(stream->chan->handle,
+ stream->buf, pos);
+ if (ret != 0) {
+ ret = errno;
+ perror("kernctl_snapshot_get_produced");
+ }
+
+ return ret;
+}
+
+int lttng_ustconsumer_recv_cmd(struct lttng_consumer_local_data *ctx,
+ int sock, struct pollfd *consumer_sockpoll)
+{
+ ssize_t ret;
+ struct lttcomm_consumer_msg msg;
+
+ ret = lttcomm_recv_unix_sock(sock, &msg, sizeof(msg));
+ if (ret != sizeof(msg)) {
+ lttng_consumer_send_error(ctx, CONSUMERD_ERROR_RECV_FD);
+ return ret;
+ }
+ if (msg.cmd_type == LTTNG_CONSUMER_STOP) {
+ return -ENOENT;
+ }
+
+ switch (msg.cmd_type) {
+ case LTTNG_CONSUMER_ADD_CHANNEL:
+ {
+ struct lttng_consumer_channel *new_channel;
+ int fds[1];
+ size_t nb_fd = 1;
+
+ /* block */
+ if (lttng_consumer_poll_socket(consumer_sockpoll) < 0) {
+ return -EINTR;
+ }
+ ret = lttcomm_recv_fds_unix_sock(sock, fds, nb_fd);
+ if (ret != sizeof(fds)) {
+ lttng_consumer_send_error(ctx, CONSUMERD_ERROR_RECV_FD);
+ return ret;
+ }
+
+ DBG("consumer_add_channel %d", msg.u.channel.channel_key);
+
+ new_channel = consumer_allocate_channel(msg.u.channel.channel_key,
+ fds[0], -1,
+ msg.u.channel.mmap_len,
+ msg.u.channel.max_sb_size);
+ if (new_channel == NULL) {
+ lttng_consumer_send_error(ctx, CONSUMERD_OUTFD_ERROR);
+ goto end_nosignal;
+ }
+ if (ctx->on_recv_channel != NULL) {
+ ret = ctx->on_recv_channel(new_channel);
+ if (ret == 0) {
+ consumer_add_channel(new_channel);
+ } else if (ret < 0) {
+ goto end_nosignal;
+ }
+ } else {
+ consumer_add_channel(new_channel);
+ }
+ goto end_nosignal;
+ }
+ case LTTNG_CONSUMER_ADD_STREAM:
+ {
+ struct lttng_consumer_stream *new_stream;
+ int fds[2];
+ size_t nb_fd = 2;
+
+ /* block */
+ if (lttng_consumer_poll_socket(consumer_sockpoll) < 0) {
+ return -EINTR;
+ }
+ ret = lttcomm_recv_fds_unix_sock(sock, fds, nb_fd);
+ if (ret != sizeof(fds)) {
+ lttng_consumer_send_error(ctx, CONSUMERD_ERROR_RECV_FD);
+ return ret;
+ }
+
+ DBG("consumer_add_stream %s (%d,%d)", msg.u.stream.path_name,
+ fds[0], fds[1]);
+ assert(msg.u.stream.output == LTTNG_EVENT_MMAP);
+ new_stream = consumer_allocate_stream(msg.u.channel.channel_key,
+ msg.u.stream.stream_key,
+ fds[0], fds[1],
+ msg.u.stream.state,
+ msg.u.stream.mmap_len,
+ msg.u.stream.output,
+ msg.u.stream.path_name,
+ msg.u.stream.uid,
+ msg.u.stream.gid);
+ if (new_stream == NULL) {
+ lttng_consumer_send_error(ctx, CONSUMERD_OUTFD_ERROR);
+ goto end;
+ }
+ if (ctx->on_recv_stream != NULL) {
+ ret = ctx->on_recv_stream(new_stream);
+ if (ret == 0) {
+ consumer_add_stream(new_stream);
+ } else if (ret < 0) {
+ goto end;
+ }
+ } else {
+ consumer_add_stream(new_stream);
+ }
+ break;
+ }
+ case LTTNG_CONSUMER_UPDATE_STREAM:
+ {
+ return -ENOSYS;
+#if 0
+ if (ctx->on_update_stream != NULL) {
+ ret = ctx->on_update_stream(msg.u.stream.stream_key, msg.u.stream.state);
+ if (ret == 0) {
+ consumer_change_stream_state(msg.u.stream.stream_key, msg.u.stream.state);
+ } else if (ret < 0) {
+ goto end;
+ }
+ } else {
+ consumer_change_stream_state(msg.u.stream.stream_key,
+ msg.u.stream.state);
+ }
+#endif
+ break;
+ }
+ default:
+ break;
+ }
+end:
+ /* signal the poll thread */
+ ret = write(ctx->consumer_poll_pipe[1], "4", 1);
+ if (ret < 0) {
+ perror("write consumer poll");
+ }
+end_nosignal:
+ return 0;
+}
+
+int lttng_ustconsumer_allocate_channel(struct lttng_consumer_channel *chan)
+{
+ struct lttng_ust_object_data obj;
+
+ obj.handle = -1;
+ obj.shm_fd = chan->shm_fd;
+ obj.wait_fd = chan->wait_fd;
+ obj.memory_map_size = chan->mmap_len;
+ chan->handle = ustctl_map_channel(&obj);
+ if (!chan->handle) {
+ return -ENOMEM;
+ }
+ chan->wait_fd_is_copy = 1;
+ chan->shm_fd = -1;
+
+ return 0;
+}
+
+void lttng_ustconsumer_on_stream_hangup(struct lttng_consumer_stream *stream)
+{
+ ustctl_flush_buffer(stream->chan->handle, stream->buf, 0);
+ stream->hangup_flush_done = 1;
+}
+
+void lttng_ustconsumer_del_channel(struct lttng_consumer_channel *chan)
+{
+ ustctl_unmap_channel(chan->handle);
+}
+
+int lttng_ustconsumer_allocate_stream(struct lttng_consumer_stream *stream)
+{
+ struct lttng_ust_object_data obj;
+ int ret;
+
+ obj.handle = -1;
+ obj.shm_fd = stream->shm_fd;
+ obj.wait_fd = stream->wait_fd;
+ obj.memory_map_size = stream->mmap_len;
+ ret = ustctl_add_stream(stream->chan->handle, &obj);
+ if (ret)
+ return ret;
+ stream->buf = ustctl_open_stream_read(stream->chan->handle, stream->cpu);
+ if (!stream->buf)
+ return -EBUSY;
+ /* ustctl_open_stream_read has closed the shm fd. */
+ stream->wait_fd_is_copy = 1;
+ stream->shm_fd = -1;
+
+ stream->mmap_base = ustctl_get_mmap_base(stream->chan->handle, stream->buf);
+ if (!stream->mmap_base) {
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+void lttng_ustconsumer_del_stream(struct lttng_consumer_stream *stream)
+{
+ ustctl_close_stream_read(stream->chan->handle, stream->buf);
+}
+
+
+int lttng_ustconsumer_read_subbuffer(struct lttng_consumer_stream *stream,
+ struct lttng_consumer_local_data *ctx)
+{
+ unsigned long len;
+ int err;
+ long ret = 0;
+ struct lttng_ust_shm_handle *handle;
+ struct lttng_ust_lib_ring_buffer *buf;
+ char dummy;
+ ssize_t readlen;
+
+ DBG("In read_subbuffer (wait_fd: %d, stream key: %d)",
+ stream->wait_fd, stream->key);
+
+ /* We can consume the 1 byte written into the wait_fd by UST */
+ if (!stream->hangup_flush_done) {
+ do {
+ readlen = read(stream->wait_fd, &dummy, 1);
+ } while (readlen == -1 && errno == -EINTR);
+ if (readlen == -1) {
+ ret = readlen;
+ goto end;
+ }
+ }
+
+ buf = stream->buf;
+ handle = stream->chan->handle;
+ /* Get the next subbuffer */
+ err = ustctl_get_next_subbuf(handle, buf);
+ if (err != 0) {
+ ret = -ret; /* ustctl_get_next_subbuf returns negative, caller expect positive. */
+ /*
+ * This is a debug message even for single-threaded consumer,
+ * because poll() have more relaxed criterions than get subbuf,
+ * so get_subbuf may fail for short race windows where poll()
+ * would issue wakeups.
+ */
+ DBG("Reserving sub buffer failed (everything is normal, "
+ "it is due to concurrency)");
+ goto end;
+ }
+ assert(stream->output == LTTNG_EVENT_MMAP);
+ /* read the used subbuffer size */
+ err = ustctl_get_padded_subbuf_size(handle, buf, &len);
+ assert(err == 0);
+ /* write the subbuffer to the tracefile */
+ ret = lttng_consumer_on_read_subbuffer_mmap(ctx, stream, len);
+ if (ret < 0) {
+ /*
+ * display the error but continue processing to try
+ * to release the subbuffer
+ */
+ ERR("Error writing to tracefile");
+ }
+ err = ustctl_put_next_subbuf(handle, buf);
+ assert(err == 0);
+end:
+ return ret;
+}
+
+int lttng_ustconsumer_on_recv_stream(struct lttng_consumer_stream *stream)
+{
+ int ret;
+
+ /* Opening the tracefile in write mode */
+ if (stream->path_name != NULL) {
+ ret = run_as_open(stream->path_name,
+ O_WRONLY|O_CREAT|O_TRUNC,
+ S_IRWXU|S_IRWXG|S_IRWXO,
+ stream->uid, stream->gid);
+ if (ret < 0) {
+ ERR("Opening %s", stream->path_name);
+ perror("open");
+ goto error;
+ }
+ stream->out_fd = ret;
+ }
+
+ /* we return 0 to let the library handle the FD internally */
+ return 0;
+
+error:
+ return ret;
+}
projects / lttng-tools.git / blobdiff