X-Git-Url: http://git.lttng.org/?a=blobdiff_plain;f=libust%2Fbuffers.c;h=bb5d8c581918c191da90e370dafd00c667dcac08;hb=86699c2035dd69428706ade2d6dfb150ada757cb;hp=9651beb916db5d78b8acbae83ded896513963c3f;hpb=909bc43f70be2b1d3efcefe33121ee1e99d9895b;p=ust.git diff --git a/libust/buffers.c b/libust/buffers.c index 9651beb..bb5d8c5 100644 --- a/libust/buffers.c +++ b/libust/buffers.c @@ -25,9 +25,10 @@ #include #include #include -#include -#include #include + +#include + #include "buffers.h" #include "channels.h" #include "tracer.h" @@ -49,50 +50,88 @@ static int get_n_cpus(void) int result; static int n_cpus = 0; - if(n_cpus) { - return n_cpus; - } + if(!n_cpus) { + /* On Linux, when some processors are offline + * _SC_NPROCESSORS_CONF counts the offline + * processors, whereas _SC_NPROCESSORS_ONLN + * does not. If we used _SC_NPROCESSORS_ONLN, + * getcpu() could return a value greater than + * this sysconf, in which case the arrays + * indexed by processor would overflow. + */ + result = sysconf(_SC_NPROCESSORS_CONF); + if(result == -1) { + return -1; + } - /* On Linux, when some processors are offline - * _SC_NPROCESSORS_CONF counts the offline - * processors, whereas _SC_NPROCESSORS_ONLN - * does not. If we used _SC_NPROCESSORS_ONLN, - * getcpu() could return a value greater than - * this sysconf, in which case the arrays - * indexed by processor would overflow. - */ - result = sysconf(_SC_NPROCESSORS_CONF); - if(result == -1) { - return -1; + n_cpus = result; } - n_cpus = result; - - return result; + return n_cpus; } -/* _ust_buffers_write() +/** + * _ust_buffers_strncpy_fixup - Fix an incomplete string in a ltt_relay buffer. + * @buf : buffer + * @offset : offset within the buffer + * @len : length to write + * @copied: string actually copied + * @terminated: does string end with \0 * - * @buf: destination buffer - * @offset: offset in destination - * @src: source buffer - * @len: length of source - * @cpy: already copied + * Fills string with "X" if incomplete. */ - -void _ust_buffers_write(struct ust_buffer *buf, size_t offset, - const void *src, size_t len, ssize_t cpy) +void _ust_buffers_strncpy_fixup(struct ust_buffer *buf, size_t offset, + size_t len, size_t copied, int terminated) { - do { - len -= cpy; - src += cpy; - offset += cpy; + size_t buf_offset, cpy; + + if (copied == len) { + /* + * Deal with non-terminated string. + */ + assert(!terminated); + offset += copied - 1; + buf_offset = BUFFER_OFFSET(offset, buf->chan); + /* + * Underlying layer should never ask for writes across + * subbuffers. + */ + assert(buf_offset + < buf->chan->subbuf_size*buf->chan->subbuf_cnt); + ust_buffers_do_memset(buf->buf_data + buf_offset, '\0', 1); + return; + } + + /* + * Deal with incomplete string. + * Overwrite string's \0 with X too. + */ + cpy = copied - 1; + assert(terminated); + len -= cpy; + offset += cpy; + buf_offset = BUFFER_OFFSET(offset, buf->chan); - WARN_ON(offset >= buf->buf_size); + /* + * Underlying layer should never ask for writes across subbuffers. + */ + assert(buf_offset + < buf->chan->subbuf_size*buf->chan->subbuf_cnt); - cpy = min_t(size_t, len, buf->buf_size - offset); - ust_buffers_do_copy(buf->buf_data + offset, src, cpy); - } while (unlikely(len != cpy)); + ust_buffers_do_memset(buf->buf_data + buf_offset, + 'X', len); + + /* + * Overwrite last 'X' with '\0'. + */ + offset += len - 1; + buf_offset = BUFFER_OFFSET(offset, buf->chan); + /* + * Underlying layer should never ask for writes across subbuffers. + */ + assert(buf_offset + < buf->chan->subbuf_size*buf->chan->subbuf_cnt); + ust_buffers_do_memset(buf->buf_data + buf_offset, '\0', 1); } static int ust_buffers_init_buffer(struct ust_trace *trace, @@ -164,7 +203,7 @@ int ust_buffers_create_buf(struct ust_channel *channel, int cpu) static void ust_buffers_destroy_channel(struct kref *kref) { - struct ust_channel *chan = container_of(kref, struct ust_channel, kref); + struct ust_channel *chan = _ust_container_of(kref, struct ust_channel, kref); free(chan); } @@ -186,7 +225,7 @@ static void ust_buffers_destroy_buf(struct ust_buffer *buf) /* called from kref_put */ static void ust_buffers_remove_buf(struct kref *kref) { - struct ust_buffer *buf = container_of(kref, struct ust_buffer, kref); + struct ust_buffer *buf = _ust_container_of(kref, struct ust_buffer, kref); ust_buffers_destroy_buf(buf); } @@ -243,14 +282,14 @@ int ust_buffers_channel_open(struct ust_channel *chan, size_t subbuf_size, size_ kref_init(&chan->kref); - mutex_lock(&ust_buffers_channels_mutex); + pthread_mutex_lock(&ust_buffers_channels_mutex); for(i=0; in_cpus; i++) { result = ust_buffers_open_buf(chan, i); if (result == -1) goto error; } list_add(&chan->list, &ust_buffers_channels); - mutex_unlock(&ust_buffers_channels_mutex); + pthread_mutex_unlock(&ust_buffers_channels_mutex); return 0; @@ -263,7 +302,7 @@ error: } kref_put(&chan->kref, ust_buffers_destroy_channel); - mutex_unlock(&ust_buffers_channels_mutex); + pthread_mutex_unlock(&ust_buffers_channels_mutex); return -1; } @@ -273,7 +312,7 @@ void ust_buffers_channel_close(struct ust_channel *chan) if(!chan) return; - mutex_lock(&ust_buffers_channels_mutex); + pthread_mutex_lock(&ust_buffers_channels_mutex); for(i=0; in_cpus; i++) { /* FIXME: if we make it here, then all buffers were necessarily allocated. Moreover, we don't * initialize to NULL so we cannot use this check. Should we? */ @@ -283,7 +322,7 @@ void ust_buffers_channel_close(struct ust_channel *chan) list_del(&chan->list); kref_put(&chan->kref, ust_buffers_destroy_channel); - mutex_unlock(&ust_buffers_channels_mutex); + pthread_mutex_unlock(&ust_buffers_channels_mutex); } /* @@ -479,93 +518,6 @@ int ust_buffers_put_subbuf(struct ust_buffer *buf, unsigned long uconsumed_old) return 0; } -//ust// static void switch_buffer(unsigned long data) -//ust// { -//ust// struct ltt_channel_buf_struct *ltt_buf = -//ust// (struct ltt_channel_buf_struct *)data; -//ust// struct rchan_buf *buf = ltt_buf->rbuf; -//ust// -//ust// if (buf) -//ust// ltt_force_switch(buf, FORCE_ACTIVE); -//ust// -//ust// ltt_buf->switch_timer.expires += ltt_buf->switch_timer_interval; -//ust// add_timer_on(<t_buf->switch_timer, smp_processor_id()); -//ust// } -//ust// -//ust// static void start_switch_timer(struct ltt_channel_struct *ltt_channel) -//ust// { -//ust// struct rchan *rchan = ltt_channel->trans_channel_data; -//ust// int cpu; -//ust// -//ust// if (!ltt_channel->switch_timer_interval) -//ust// return; -//ust// -//ust// // TODO : hotplug -//ust// for_each_online_cpu(cpu) { -//ust// struct ltt_channel_buf_struct *ltt_buf; -//ust// struct rchan_buf *buf; -//ust// -//ust// buf = rchan->buf[cpu]; -//ust// ltt_buf = buf->chan_private; -//ust// buf->random_access = 1; -//ust// ltt_buf->switch_timer_interval = -//ust// ltt_channel->switch_timer_interval; -//ust// init_timer(<t_buf->switch_timer); -//ust// ltt_buf->switch_timer.function = switch_buffer; -//ust// ltt_buf->switch_timer.expires = jiffies + -//ust// ltt_buf->switch_timer_interval; -//ust// ltt_buf->switch_timer.data = (unsigned long)ltt_buf; -//ust// add_timer_on(<t_buf->switch_timer, cpu); -//ust// } -//ust// } -//ust// -//ust// /* -//ust// * Cannot use del_timer_sync with add_timer_on, so use an IPI to locally -//ust// * delete the timer. -//ust// */ -//ust// static void stop_switch_timer_ipi(void *info) -//ust// { -//ust// struct ltt_channel_buf_struct *ltt_buf = -//ust// (struct ltt_channel_buf_struct *)info; -//ust// -//ust// del_timer(<t_buf->switch_timer); -//ust// } -//ust// -//ust// static void stop_switch_timer(struct ltt_channel_struct *ltt_channel) -//ust// { -//ust// struct rchan *rchan = ltt_channel->trans_channel_data; -//ust// int cpu; -//ust// -//ust// if (!ltt_channel->switch_timer_interval) -//ust// return; -//ust// -//ust// // TODO : hotplug -//ust// for_each_online_cpu(cpu) { -//ust// struct ltt_channel_buf_struct *ltt_buf; -//ust// struct rchan_buf *buf; -//ust// -//ust// buf = rchan->buf[cpu]; -//ust// ltt_buf = buf->chan_private; -//ust// smp_call_function(stop_switch_timer_ipi, ltt_buf, 1); -//ust// buf->random_access = 0; -//ust// } -//ust// } - -//ust// static void ust_buffers_print_written(struct ust_channel *chan, -//ust// long cons_off, unsigned int cpu) -//ust// { -//ust// struct ust_buffer *buf = chan->buf[cpu]; -//ust// long cons_idx, events_count; -//ust// -//ust// cons_idx = SUBBUF_INDEX(cons_off, chan); -//ust// events_count = uatomic_read(&buf->commit_count[cons_idx].events); -//ust// -//ust// if (events_count) -//ust// printk(KERN_INFO -//ust// "channel %s: %lu events written (cpu %u, index %lu)\n", -//ust// chan->channel_name, events_count, cpu, cons_idx); -//ust// } - static void ltt_relay_print_subbuffer_errors( struct ust_channel *channel, long cons_off, int cpu) @@ -640,7 +592,7 @@ static void ltt_relay_print_buffer_errors(struct ust_channel *channel, int cpu) static void ltt_relay_release_channel(struct kref *kref) { - struct ust_channel *ltt_chan = container_of(kref, + struct ust_channel *ltt_chan = _ust_container_of(kref, struct ust_channel, kref); free(ltt_chan->buf); } @@ -725,12 +677,6 @@ static int ust_buffers_init_buffer(struct ust_trace *trace, buf->data_ready_fd_read = fds[0]; buf->data_ready_fd_write = fds[1]; - /* FIXME: do we actually need this? */ - result = fcntl(fds[0], F_SETFL, O_NONBLOCK); - if(result == -1) { - PERROR("fcntl"); - } - //ust// buf->commit_seq = malloc(sizeof(buf->commit_seq) * n_subbufs); //ust// if(!ltt_buf->commit_seq) { //ust// return -1; @@ -831,11 +777,11 @@ static int ust_buffers_create_channel(const char *trace_name, struct ust_trace * ltt_chan->commit_count_mask = (~0UL >> ltt_chan->n_subbufs_order); ltt_chan->n_cpus = get_n_cpus(); //ust// ltt_chan->buf = percpu_alloc_mask(sizeof(struct ltt_channel_buf_struct), GFP_KERNEL, cpu_possible_map); - ltt_chan->buf = (void *) malloc(ltt_chan->n_cpus * sizeof(void *)); + ltt_chan->buf = (void *) zmalloc(ltt_chan->n_cpus * sizeof(void *)); if(ltt_chan->buf == NULL) { goto error; } - ltt_chan->buf_struct_shmids = (int *) malloc(ltt_chan->n_cpus * sizeof(int)); + ltt_chan->buf_struct_shmids = (int *) zmalloc(ltt_chan->n_cpus * sizeof(int)); if(ltt_chan->buf_struct_shmids == NULL) goto free_buf; @@ -865,26 +811,6 @@ error: return -1; } -/* - * LTTng channel flush function. - * - * Must be called when no tracing is active in the channel, because of - * accesses across CPUs. - */ -static notrace void ltt_relay_buffer_flush(struct ust_buffer *buf) -{ - int result; - -//ust// buf->finalized = 1; - ltt_force_switch(buf, FORCE_FLUSH); - - result = write(buf->data_ready_fd_write, "1", 1); - if(result == -1) { - PERROR("write (in ltt_relay_buffer_flush)"); - ERR("this should never happen!"); - } -} - static void ltt_relay_async_wakeup_chan(struct ust_channel *ltt_channel) { //ust// unsigned int i; @@ -907,7 +833,7 @@ static void ltt_relay_finish_buffer(struct ust_channel *channel, unsigned int cp if (channel->buf[cpu]) { struct ust_buffer *buf = channel->buf[cpu]; - ltt_relay_buffer_flush(buf); + ltt_force_switch(buf, FORCE_FLUSH); //ust// ltt_relay_wake_writers(ltt_buf); /* closing the pipe tells the consumer the buffer is finished */ @@ -936,386 +862,6 @@ static void ltt_relay_remove_channel(struct ust_channel *channel) kref_put(&channel->kref, ltt_relay_release_channel); } -//ust// /* -//ust// * Returns : -//ust// * 0 if ok -//ust// * !0 if execution must be aborted. -//ust// */ -//ust// static inline int ltt_relay_try_reserve( -//ust// struct ust_channel *channel, struct ust_buffer *buf, -//ust// struct ltt_reserve_switch_offsets *offsets, size_t data_size, -//ust// u64 *tsc, unsigned int *rflags, int largest_align) -//ust// { -//ust// offsets->begin = uatomic_read(&buf->offset); -//ust// offsets->old = offsets->begin; -//ust// offsets->begin_switch = 0; -//ust// offsets->end_switch_current = 0; -//ust// offsets->end_switch_old = 0; -//ust// -//ust// *tsc = trace_clock_read64(); -//ust// if (last_tsc_overflow(buf, *tsc)) -//ust// *rflags = LTT_RFLAG_ID_SIZE_TSC; -//ust// -//ust// if (SUBBUF_OFFSET(offsets->begin, buf->chan) == 0) { -//ust// offsets->begin_switch = 1; /* For offsets->begin */ -//ust// } else { -//ust// offsets->size = ust_get_header_size(channel, -//ust// offsets->begin, data_size, -//ust// &offsets->before_hdr_pad, *rflags); -//ust// offsets->size += ltt_align(offsets->begin + offsets->size, -//ust// largest_align) -//ust// + data_size; -//ust// if ((SUBBUF_OFFSET(offsets->begin, buf->chan) + offsets->size) -//ust// > buf->chan->subbuf_size) { -//ust// offsets->end_switch_old = 1; /* For offsets->old */ -//ust// offsets->begin_switch = 1; /* For offsets->begin */ -//ust// } -//ust// } -//ust// if (offsets->begin_switch) { -//ust// long subbuf_index; -//ust// -//ust// if (offsets->end_switch_old) -//ust// offsets->begin = SUBBUF_ALIGN(offsets->begin, -//ust// buf->chan); -//ust// offsets->begin = offsets->begin + ltt_subbuffer_header_size(); -//ust// /* Test new buffer integrity */ -//ust// subbuf_index = SUBBUF_INDEX(offsets->begin, buf->chan); -//ust// offsets->reserve_commit_diff = -//ust// (BUFFER_TRUNC(offsets->begin, buf->chan) -//ust// >> channel->n_subbufs_order) -//ust// - (uatomic_read(&buf->commit_count[subbuf_index]) -//ust// & channel->commit_count_mask); -//ust// if (offsets->reserve_commit_diff == 0) { -//ust// long consumed; -//ust// -//ust// consumed = uatomic_read(&buf->consumed); -//ust// -//ust// /* Next buffer not corrupted. */ -//ust// if (!channel->overwrite && -//ust// (SUBBUF_TRUNC(offsets->begin, buf->chan) -//ust// - SUBBUF_TRUNC(consumed, buf->chan)) -//ust// >= channel->alloc_size) { -//ust// -//ust// long consumed_idx = SUBBUF_INDEX(consumed, buf->chan); -//ust// long commit_count = uatomic_read(&buf->commit_count[consumed_idx]); -//ust// if(((commit_count - buf->chan->subbuf_size) & channel->commit_count_mask) - (BUFFER_TRUNC(consumed, buf->chan) >> channel->n_subbufs_order) != 0) { -//ust// WARN("Event dropped. Caused by non-committed event."); -//ust// } -//ust// else { -//ust// WARN("Event dropped. Caused by non-consumed buffer."); -//ust// } -//ust// /* -//ust// * We do not overwrite non consumed buffers -//ust// * and we are full : event is lost. -//ust// */ -//ust// uatomic_inc(&buf->events_lost); -//ust// return -1; -//ust// } else { -//ust// /* -//ust// * next buffer not corrupted, we are either in -//ust// * overwrite mode or the buffer is not full. -//ust// * It's safe to write in this new subbuffer. -//ust// */ -//ust// } -//ust// } else { -//ust// /* -//ust// * Next subbuffer corrupted. Force pushing reader even -//ust// * in normal mode. It's safe to write in this new -//ust// * subbuffer. -//ust// */ -//ust// } -//ust// offsets->size = ust_get_header_size(channel, -//ust// offsets->begin, data_size, -//ust// &offsets->before_hdr_pad, *rflags); -//ust// offsets->size += ltt_align(offsets->begin + offsets->size, -//ust// largest_align) -//ust// + data_size; -//ust// if ((SUBBUF_OFFSET(offsets->begin, buf->chan) + offsets->size) -//ust// > buf->chan->subbuf_size) { -//ust// /* -//ust// * Event too big for subbuffers, report error, don't -//ust// * complete the sub-buffer switch. -//ust// */ -//ust// uatomic_inc(&buf->events_lost); -//ust// return -1; -//ust// } else { -//ust// /* -//ust// * We just made a successful buffer switch and the event -//ust// * fits in the new subbuffer. Let's write. -//ust// */ -//ust// } -//ust// } else { -//ust// /* -//ust// * Event fits in the current buffer and we are not on a switch -//ust// * boundary. It's safe to write. -//ust// */ -//ust// } -//ust// offsets->end = offsets->begin + offsets->size; -//ust// -//ust// if ((SUBBUF_OFFSET(offsets->end, buf->chan)) == 0) { -//ust// /* -//ust// * The offset_end will fall at the very beginning of the next -//ust// * subbuffer. -//ust// */ -//ust// offsets->end_switch_current = 1; /* For offsets->begin */ -//ust// } -//ust// return 0; -//ust// } -//ust// -//ust// /* -//ust// * Returns : -//ust// * 0 if ok -//ust// * !0 if execution must be aborted. -//ust// */ -//ust// static inline int ltt_relay_try_switch( -//ust// enum force_switch_mode mode, -//ust// struct ust_channel *channel, -//ust// struct ust_buffer *buf, -//ust// struct ltt_reserve_switch_offsets *offsets, -//ust// u64 *tsc) -//ust// { -//ust// long subbuf_index; -//ust// -//ust// offsets->begin = uatomic_read(&buf->offset); -//ust// offsets->old = offsets->begin; -//ust// offsets->begin_switch = 0; -//ust// offsets->end_switch_old = 0; -//ust// -//ust// *tsc = trace_clock_read64(); -//ust// -//ust// if (SUBBUF_OFFSET(offsets->begin, buf->chan) != 0) { -//ust// offsets->begin = SUBBUF_ALIGN(offsets->begin, buf->chan); -//ust// offsets->end_switch_old = 1; -//ust// } else { -//ust// /* we do not have to switch : buffer is empty */ -//ust// return -1; -//ust// } -//ust// if (mode == FORCE_ACTIVE) -//ust// offsets->begin += ltt_subbuffer_header_size(); -//ust// /* -//ust// * Always begin_switch in FORCE_ACTIVE mode. -//ust// * Test new buffer integrity -//ust// */ -//ust// subbuf_index = SUBBUF_INDEX(offsets->begin, buf->chan); -//ust// offsets->reserve_commit_diff = -//ust// (BUFFER_TRUNC(offsets->begin, buf->chan) -//ust// >> channel->n_subbufs_order) -//ust// - (uatomic_read(&buf->commit_count[subbuf_index]) -//ust// & channel->commit_count_mask); -//ust// if (offsets->reserve_commit_diff == 0) { -//ust// /* Next buffer not corrupted. */ -//ust// if (mode == FORCE_ACTIVE -//ust// && !channel->overwrite -//ust// && offsets->begin - uatomic_read(&buf->consumed) -//ust// >= channel->alloc_size) { -//ust// /* -//ust// * We do not overwrite non consumed buffers and we are -//ust// * full : ignore switch while tracing is active. -//ust// */ -//ust// return -1; -//ust// } -//ust// } else { -//ust// /* -//ust// * Next subbuffer corrupted. Force pushing reader even in normal -//ust// * mode -//ust// */ -//ust// } -//ust// offsets->end = offsets->begin; -//ust// return 0; -//ust// } -//ust// -//ust// static inline void ltt_reserve_push_reader( -//ust// struct ust_channel *channel, -//ust// struct ust_buffer *buf, -//ust// struct ltt_reserve_switch_offsets *offsets) -//ust// { -//ust// long consumed_old, consumed_new; -//ust// -//ust// do { -//ust// consumed_old = uatomic_read(&buf->consumed); -//ust// /* -//ust// * If buffer is in overwrite mode, push the reader consumed -//ust// * count if the write position has reached it and we are not -//ust// * at the first iteration (don't push the reader farther than -//ust// * the writer). This operation can be done concurrently by many -//ust// * writers in the same buffer, the writer being at the farthest -//ust// * write position sub-buffer index in the buffer being the one -//ust// * which will win this loop. -//ust// * If the buffer is not in overwrite mode, pushing the reader -//ust// * only happens if a sub-buffer is corrupted. -//ust// */ -//ust// if ((SUBBUF_TRUNC(offsets->end-1, buf->chan) -//ust// - SUBBUF_TRUNC(consumed_old, buf->chan)) -//ust// >= channel->alloc_size) -//ust// consumed_new = SUBBUF_ALIGN(consumed_old, buf->chan); -//ust// else { -//ust// consumed_new = consumed_old; -//ust// break; -//ust// } -//ust// } while (uatomic_cmpxchg(&buf->consumed, consumed_old, -//ust// consumed_new) != consumed_old); -//ust// -//ust// if (consumed_old != consumed_new) { -//ust// /* -//ust// * Reader pushed : we are the winner of the push, we can -//ust// * therefore reequilibrate reserve and commit. Atomic increment -//ust// * of the commit count permits other writers to play around -//ust// * with this variable before us. We keep track of -//ust// * corrupted_subbuffers even in overwrite mode : -//ust// * we never want to write over a non completely committed -//ust// * sub-buffer : possible causes : the buffer size is too low -//ust// * compared to the unordered data input, or there is a writer -//ust// * that died between the reserve and the commit. -//ust// */ -//ust// if (offsets->reserve_commit_diff) { -//ust// /* -//ust// * We have to alter the sub-buffer commit count. -//ust// * We do not deliver the previous subbuffer, given it -//ust// * was either corrupted or not consumed (overwrite -//ust// * mode). -//ust// */ -//ust// uatomic_add(&buf->commit_count[SUBBUF_INDEX(offsets->begin, buf->chan)], -//ust// offsets->reserve_commit_diff); -//ust// if (!channel->overwrite -//ust// || offsets->reserve_commit_diff -//ust// != channel->subbuf_size) { -//ust// /* -//ust// * The reserve commit diff was not subbuf_size : -//ust// * it means the subbuffer was partly written to -//ust// * and is therefore corrupted. If it is multiple -//ust// * of subbuffer size and we are in flight -//ust// * recorder mode, we are skipping over a whole -//ust// * subbuffer. -//ust// */ -//ust// uatomic_inc(&buf->corrupted_subbuffers); -//ust// } -//ust// } -//ust// } -//ust// } -//ust// -//ust// /** -//ust// * ltt_relay_reserve_slot - Atomic slot reservation in a LTTng buffer. -//ust// * @trace: the trace structure to log to. -//ust// * @ltt_channel: channel structure -//ust// * @transport_data: data structure specific to ltt relay -//ust// * @data_size: size of the variable length data to log. -//ust// * @slot_size: pointer to total size of the slot (out) -//ust// * @buf_offset : pointer to reserved buffer offset (out) -//ust// * @tsc: pointer to the tsc at the slot reservation (out) -//ust// * @cpu: cpuid -//ust// * -//ust// * Return : -ENOSPC if not enough space, else returns 0. -//ust// * It will take care of sub-buffer switching. -//ust// */ -//ust// static notrace int ltt_relay_reserve_slot(struct ust_trace *trace, -//ust// struct ust_channel *channel, void **transport_data, -//ust// size_t data_size, size_t *slot_size, long *buf_offset, u64 *tsc, -//ust// unsigned int *rflags, int largest_align, int cpu) -//ust// { -//ust// struct ust_buffer *buf = *transport_data = channel->buf[cpu]; -//ust// struct ltt_reserve_switch_offsets offsets; -//ust// -//ust// offsets.reserve_commit_diff = 0; -//ust// offsets.size = 0; -//ust// -//ust// /* -//ust// * Perform retryable operations. -//ust// */ -//ust// if (ltt_nesting > 4) { -//ust// uatomic_inc(&buf->events_lost); -//ust// return -EPERM; -//ust// } -//ust// do { -//ust// if (ltt_relay_try_reserve(channel, buf, &offsets, data_size, tsc, rflags, -//ust// largest_align)) -//ust// return -ENOSPC; -//ust// } while (uatomic_cmpxchg(&buf->offset, offsets.old, -//ust// offsets.end) != offsets.old); -//ust// -//ust// /* -//ust// * Atomically update last_tsc. This update races against concurrent -//ust// * atomic updates, but the race will always cause supplementary full TSC -//ust// * events, never the opposite (missing a full TSC event when it would be -//ust// * needed). -//ust// */ -//ust// save_last_tsc(buf, *tsc); -//ust// -//ust// /* -//ust// * Push the reader if necessary -//ust// */ -//ust// ltt_reserve_push_reader(channel, buf, &offsets); -//ust// -//ust// /* -//ust// * Switch old subbuffer if needed. -//ust// */ -//ust// if (offsets.end_switch_old) -//ust// ltt_reserve_switch_old_subbuf(channel, buf, &offsets, tsc); -//ust// -//ust// /* -//ust// * Populate new subbuffer. -//ust// */ -//ust// if (offsets.begin_switch) -//ust// ltt_reserve_switch_new_subbuf(channel, buf, &offsets, tsc); -//ust// -//ust// if (offsets.end_switch_current) -//ust// ltt_reserve_end_switch_current(channel, buf, &offsets, tsc); -//ust// -//ust// *slot_size = offsets.size; -//ust// *buf_offset = offsets.begin + offsets.before_hdr_pad; -//ust// return 0; -//ust// } -//ust// -//ust// /* -//ust// * Force a sub-buffer switch for a per-cpu buffer. This operation is -//ust// * completely reentrant : can be called while tracing is active with -//ust// * absolutely no lock held. -//ust// */ -//ust// static notrace void ltt_force_switch(struct ust_buffer *buf, -//ust// enum force_switch_mode mode) -//ust// { -//ust// struct ust_channel *channel = buf->chan; -//ust// struct ltt_reserve_switch_offsets offsets; -//ust// u64 tsc; -//ust// -//ust// offsets.reserve_commit_diff = 0; -//ust// offsets.size = 0; -//ust// -//ust// /* -//ust// * Perform retryable operations. -//ust// */ -//ust// do { -//ust// if (ltt_relay_try_switch(mode, channel, buf, &offsets, &tsc)) -//ust// return; -//ust// } while (uatomic_cmpxchg(&buf->offset, offsets.old, -//ust// offsets.end) != offsets.old); -//ust// -//ust// /* -//ust// * Atomically update last_tsc. This update races against concurrent -//ust// * atomic updates, but the race will always cause supplementary full TSC -//ust// * events, never the opposite (missing a full TSC event when it would be -//ust// * needed). -//ust// */ -//ust// save_last_tsc(buf, tsc); -//ust// -//ust// /* -//ust// * Push the reader if necessary -//ust// */ -//ust// if (mode == FORCE_ACTIVE) -//ust// ltt_reserve_push_reader(channel, buf, &offsets); -//ust// -//ust// /* -//ust// * Switch old subbuffer if needed. -//ust// */ -//ust// if (offsets.end_switch_old) -//ust// ltt_reserve_switch_old_subbuf(channel, buf, &offsets, &tsc); -//ust// -//ust// /* -//ust// * Populate new subbuffer. -//ust// */ -//ust// if (mode == FORCE_ACTIVE) -//ust// ltt_reserve_switch_new_subbuf(channel, buf, &offsets, &tsc); -//ust// } - /* * ltt_reserve_switch_old_subbuf: switch old subbuffer * @@ -1352,7 +898,7 @@ static void ltt_reserve_switch_old_subbuf( * This compiler barrier is upgraded into a smp_wmb() by the IPI * sent by get_subbuf() when it does its smp_rmb(). */ - barrier(); + smp_wmb(); uatomic_add(&buf->commit_count[oldidx].cc, padding_size); commit_count = uatomic_read(&buf->commit_count[oldidx].cc); ltt_check_deliver(chan, buf, offsets->old - 1, commit_count, oldidx); @@ -1381,7 +927,7 @@ static void ltt_reserve_switch_new_subbuf( * This compiler barrier is upgraded into a smp_wmb() by the IPI * sent by get_subbuf() when it does its smp_rmb(). */ - barrier(); + smp_wmb(); uatomic_add(&buf->commit_count[beginidx].cc, ltt_subbuffer_header_size()); commit_count = uatomic_read(&buf->commit_count[beginidx].cc); /* Check if the written buffer has to be delivered */ @@ -1426,7 +972,7 @@ static void ltt_reserve_end_switch_current( * This compiler barrier is upgraded into a smp_wmb() by the IPI * sent by get_subbuf() when it does its smp_rmb(). */ - barrier(); + smp_wmb(); uatomic_add(&buf->commit_count[endidx].cc, padding_size); commit_count = uatomic_read(&buf->commit_count[endidx].cc); ltt_check_deliver(chan, buf, @@ -1689,12 +1235,14 @@ static int ltt_relay_try_reserve_slow(struct ust_channel *chan, struct ust_buffe * Return : -ENOSPC if not enough space, else returns 0. * It will take care of sub-buffer switching. */ -int ltt_reserve_slot_lockless_slow(struct ust_trace *trace, - struct ust_channel *chan, void **transport_data, - size_t data_size, size_t *slot_size, long *buf_offset, u64 *tsc, - unsigned int *rflags, int largest_align, int cpu) +int ltt_reserve_slot_lockless_slow(struct ust_channel *chan, + struct ust_trace *trace, size_t data_size, + int largest_align, int cpu, + struct ust_buffer **ret_buf, + size_t *slot_size, long *buf_offset, + u64 *tsc, unsigned int *rflags) { - struct ust_buffer *buf = chan->buf[cpu]; + struct ust_buffer *buf = *ret_buf = chan->buf[cpu]; struct ltt_reserve_switch_offsets offsets; offsets.size = 0; @@ -1772,8 +1320,7 @@ static void __attribute__((destructor)) ust_buffers_exit(void) ltt_transport_unregister(&ust_relay_transport); } -size_t ltt_write_event_header_slow(struct ust_trace *trace, - struct ust_channel *channel, +size_t ltt_write_event_header_slow(struct ust_channel *channel, struct ust_buffer *buf, long buf_offset, u16 eID, u32 event_size, u64 tsc, unsigned int rflags)