From: Pierre-Marc Fournier Date: Thu, 4 Mar 2010 16:33:09 +0000 (-0500) Subject: convert to uatomic ops X-Git-Tag: v0.4~46 X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=b102c2b0b07a155285716d9f7fd788662cecd54b;p=ust.git convert to uatomic ops --- diff --git a/libust/buffers.c b/libust/buffers.c index 206d5e7..c487cbf 100644 --- a/libust/buffers.c +++ b/libust/buffers.c @@ -329,8 +329,8 @@ static notrace void ltt_buffer_end(struct ust_buffer *buf, header->data_size = data_size; header->sb_size = PAGE_ALIGN(data_size); header->cycle_count_end = tsc; - header->events_lost = local_read(&buf->events_lost); - header->subbuf_corrupt = local_read(&buf->corrupted_subbuffers); + header->events_lost = uatomic_read(&buf->events_lost); + header->subbuf_corrupt = uatomic_read(&buf->corrupted_subbuffers); if(unlikely(header->events_lost > 0)) { DBG("Some events (%d) were lost in %s_%d", header->events_lost, buf->chan->channel_name, buf->cpu); } @@ -362,9 +362,9 @@ int ust_buffers_get_subbuf(struct ust_buffer *buf, long *consumed) long consumed_old, consumed_idx, commit_count, write_offset; //ust// int retval; - consumed_old = atomic_long_read(&buf->consumed); + consumed_old = uatomic_read(&buf->consumed); consumed_idx = SUBBUF_INDEX(consumed_old, buf->chan); - commit_count = local_read(&buf->commit_count[consumed_idx].cc_sb); + commit_count = uatomic_read(&buf->commit_count[consumed_idx].cc_sb); /* * Make sure we read the commit count before reading the buffer * data and the write offset. Correct consumed offset ordering @@ -416,7 +416,7 @@ int ust_buffers_get_subbuf(struct ust_buffer *buf, long *consumed) //ust// } //ust// #endif - write_offset = local_read(&buf->offset); + write_offset = uatomic_read(&buf->offset); /* * Check that the subbuffer we are trying to consume has been * already fully committed. @@ -452,13 +452,13 @@ int ust_buffers_put_subbuf(struct ust_buffer *buf, unsigned long uconsumed_old) { long consumed_new, consumed_old; - consumed_old = atomic_long_read(&buf->consumed); + consumed_old = uatomic_read(&buf->consumed); consumed_old = consumed_old & (~0xFFFFFFFFL); consumed_old = consumed_old | uconsumed_old; consumed_new = SUBBUF_ALIGN(consumed_old, buf->chan); //ust// spin_lock(<t_buf->full_lock); - if (atomic_long_cmpxchg(&buf->consumed, consumed_old, + if (uatomic_cmpxchg(&buf->consumed, consumed_old, consumed_new) != consumed_old) { /* We have been pushed by the writer : the last @@ -557,7 +557,7 @@ int ust_buffers_put_subbuf(struct ust_buffer *buf, unsigned long uconsumed_old) //ust// long cons_idx, events_count; //ust// //ust// cons_idx = SUBBUF_INDEX(cons_off, chan); -//ust// events_count = local_read(&buf->commit_count[cons_idx].events); +//ust// events_count = uatomic_read(&buf->commit_count[cons_idx].events); //ust// //ust// if (events_count) //ust// printk(KERN_INFO @@ -573,14 +573,14 @@ static void ltt_relay_print_subbuffer_errors( long cons_idx, commit_count, commit_count_sb, write_offset; cons_idx = SUBBUF_INDEX(cons_off, channel); - commit_count = local_read(<t_buf->commit_count[cons_idx].cc); - commit_count_sb = local_read(<t_buf->commit_count[cons_idx].cc_sb); + commit_count = uatomic_read(<t_buf->commit_count[cons_idx].cc); + commit_count_sb = uatomic_read(<t_buf->commit_count[cons_idx].cc_sb); /* * No need to order commit_count and write_offset reads because we * execute after trace is stopped when there are no readers left. */ - write_offset = local_read(<t_buf->offset); + write_offset = uatomic_read(<t_buf->offset); WARN( "LTT : unread channel %s offset is %ld " "and cons_off : %ld (cpu %d)\n", channel->channel_name, write_offset, cons_off, cpu); @@ -612,8 +612,8 @@ static void ltt_relay_print_errors(struct ust_trace *trace, //ust// for (cons_off = 0; cons_off < rchan->alloc_size; //ust// cons_off = SUBBUF_ALIGN(cons_off, rchan)) //ust// ust_buffers_print_written(ltt_chan, cons_off, cpu); - for (cons_off = atomic_long_read(<t_buf->consumed); - (SUBBUF_TRUNC(local_read(<t_buf->offset), + for (cons_off = uatomic_read(<t_buf->consumed); + (SUBBUF_TRUNC(uatomic_read(<t_buf->offset), channel) - cons_off) > 0; cons_off = SUBBUF_ALIGN(cons_off, channel)) @@ -625,14 +625,14 @@ static void ltt_relay_print_buffer_errors(struct ust_channel *channel, int cpu) struct ust_trace *trace = channel->trace; struct ust_buffer *ltt_buf = channel->buf[cpu]; - if (local_read(<t_buf->events_lost)) + if (uatomic_read(<t_buf->events_lost)) ERR("channel %s: %ld events lost (cpu %d)", channel->channel_name, - local_read(<t_buf->events_lost), cpu); - if (local_read(<t_buf->corrupted_subbuffers)) + uatomic_read(<t_buf->events_lost), cpu); + if (uatomic_read(<t_buf->corrupted_subbuffers)) ERR("channel %s : %ld corrupted subbuffers (cpu %d)", channel->channel_name, - local_read(<t_buf->corrupted_subbuffers), cpu); + uatomic_read(<t_buf->corrupted_subbuffers), cpu); ltt_relay_print_errors(trace, channel, cpu); } @@ -663,22 +663,22 @@ static void ltt_relay_release_channel(struct kref *kref) //ust// kref_get(&trace->kref); //ust// kref_get(&trace->ltt_transport_kref); //ust// kref_get(<t_chan->kref); -//ust// local_set(<t_buf->offset, ltt_subbuffer_header_size()); -//ust// atomic_long_set(<t_buf->consumed, 0); -//ust// atomic_long_set(<t_buf->active_readers, 0); +//ust// uatomic_set(<t_buf->offset, ltt_subbuffer_header_size()); +//ust// uatomic_set(<t_buf->consumed, 0); +//ust// uatomic_set(<t_buf->active_readers, 0); //ust// for (j = 0; j < n_subbufs; j++) -//ust// local_set(<t_buf->commit_count[j], 0); +//ust// uatomic_set(<t_buf->commit_count[j], 0); //ust// init_waitqueue_head(<t_buf->write_wait); -//ust// atomic_set(<t_buf->wakeup_readers, 0); +//ust// uatomic_set(<t_buf->wakeup_readers, 0); //ust// spin_lock_init(<t_buf->full_lock); //ust// //ust// ltt_buffer_begin_callback(buf, trace->start_tsc, 0); //ust// /* atomic_add made on local variable on data that belongs to //ust// * various CPUs : ok because tracing not started (for this cpu). */ -//ust// local_add(ltt_subbuffer_header_size(), <t_buf->commit_count[0]); +//ust// uatomic_add(<t_buf->commit_count[0], ltt_subbuffer_header_size()); //ust// -//ust// local_set(<t_buf->events_lost, 0); -//ust// local_set(<t_buf->corrupted_subbuffers, 0); +//ust// uatomic_set(<t_buf->events_lost, 0); +//ust// uatomic_set(<t_buf->corrupted_subbuffers, 0); //ust// //ust// return 0; //ust// } @@ -698,23 +698,23 @@ static int ust_buffers_init_buffer(struct ust_trace *trace, kref_get(&trace->kref); kref_get(&trace->ltt_transport_kref); kref_get(<t_chan->kref); - local_set(&buf->offset, ltt_subbuffer_header_size()); - atomic_long_set(&buf->consumed, 0); - atomic_long_set(&buf->active_readers, 0); + uatomic_set(&buf->offset, ltt_subbuffer_header_size()); + uatomic_set(&buf->consumed, 0); + uatomic_set(&buf->active_readers, 0); for (j = 0; j < n_subbufs; j++) { - local_set(&buf->commit_count[j].cc, 0); - local_set(&buf->commit_count[j].cc_sb, 0); + uatomic_set(&buf->commit_count[j].cc, 0); + uatomic_set(&buf->commit_count[j].cc_sb, 0); } //ust// init_waitqueue_head(&buf->write_wait); -//ust// atomic_set(&buf->wakeup_readers, 0); +//ust// uatomic_set(&buf->wakeup_readers, 0); //ust// spin_lock_init(&buf->full_lock); ltt_buffer_begin(buf, trace->start_tsc, 0); - local_add(ltt_subbuffer_header_size(), &buf->commit_count[0].cc); + uatomic_add(&buf->commit_count[0].cc, ltt_subbuffer_header_size()); - local_set(&buf->events_lost, 0); - local_set(&buf->corrupted_subbuffers, 0); + uatomic_set(&buf->events_lost, 0); + uatomic_set(&buf->corrupted_subbuffers, 0); result = pipe(fds); if(result == -1) { @@ -893,8 +893,8 @@ static void ltt_relay_async_wakeup_chan(struct ust_channel *ltt_channel) //ust// struct ltt_channel_buf_struct *ltt_buf = //ust// percpu_ptr(ltt_channel->buf, i); //ust// -//ust// if (atomic_read(<t_buf->wakeup_readers) == 1) { -//ust// atomic_set(<t_buf->wakeup_readers, 0); +//ust// if (uatomic_read(<t_buf->wakeup_readers) == 1) { +//ust// uatomic_set(<t_buf->wakeup_readers, 0); //ust// wake_up_interruptible(&rchan->buf[i]->read_wait); //ust// } //ust// } @@ -945,7 +945,7 @@ static void ltt_relay_remove_channel(struct ust_channel *channel) //ust// struct ltt_reserve_switch_offsets *offsets, size_t data_size, //ust// u64 *tsc, unsigned int *rflags, int largest_align) //ust// { -//ust// offsets->begin = local_read(&buf->offset); +//ust// offsets->begin = uatomic_read(&buf->offset); //ust// offsets->old = offsets->begin; //ust// offsets->begin_switch = 0; //ust// offsets->end_switch_current = 0; @@ -982,12 +982,12 @@ static void ltt_relay_remove_channel(struct ust_channel *channel) //ust// offsets->reserve_commit_diff = //ust// (BUFFER_TRUNC(offsets->begin, buf->chan) //ust// >> channel->n_subbufs_order) -//ust// - (local_read(&buf->commit_count[subbuf_index]) +//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 = atomic_long_read(&buf->consumed); +//ust// consumed = uatomic_read(&buf->consumed); //ust// //ust// /* Next buffer not corrupted. */ //ust// if (!channel->overwrite && @@ -996,7 +996,7 @@ static void ltt_relay_remove_channel(struct ust_channel *channel) //ust// >= channel->alloc_size) { //ust// //ust// long consumed_idx = SUBBUF_INDEX(consumed, buf->chan); -//ust// long commit_count = local_read(&buf->commit_count[consumed_idx]); +//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// } @@ -1007,7 +1007,7 @@ static void ltt_relay_remove_channel(struct ust_channel *channel) //ust// * We do not overwrite non consumed buffers //ust// * and we are full : event is lost. //ust// */ -//ust// local_inc(&buf->events_lost); +//ust// uatomic_inc(&buf->events_lost); //ust// return -1; //ust// } else { //ust// /* @@ -1035,7 +1035,7 @@ static void ltt_relay_remove_channel(struct ust_channel *channel) //ust// * Event too big for subbuffers, report error, don't //ust// * complete the sub-buffer switch. //ust// */ -//ust// local_inc(&buf->events_lost); +//ust// uatomic_inc(&buf->events_lost); //ust// return -1; //ust// } else { //ust// /* @@ -1075,7 +1075,7 @@ static void ltt_relay_remove_channel(struct ust_channel *channel) //ust// { //ust// long subbuf_index; //ust// -//ust// offsets->begin = local_read(&buf->offset); +//ust// offsets->begin = uatomic_read(&buf->offset); //ust// offsets->old = offsets->begin; //ust// offsets->begin_switch = 0; //ust// offsets->end_switch_old = 0; @@ -1099,13 +1099,13 @@ static void ltt_relay_remove_channel(struct ust_channel *channel) //ust// offsets->reserve_commit_diff = //ust// (BUFFER_TRUNC(offsets->begin, buf->chan) //ust// >> channel->n_subbufs_order) -//ust// - (local_read(&buf->commit_count[subbuf_index]) +//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 - atomic_long_read(&buf->consumed) +//ust// && offsets->begin - uatomic_read(&buf->consumed) //ust// >= channel->alloc_size) { //ust// /* //ust// * We do not overwrite non consumed buffers and we are @@ -1131,7 +1131,7 @@ static void ltt_relay_remove_channel(struct ust_channel *channel) //ust// long consumed_old, consumed_new; //ust// //ust// do { -//ust// consumed_old = atomic_long_read(&buf->consumed); +//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 @@ -1151,7 +1151,7 @@ static void ltt_relay_remove_channel(struct ust_channel *channel) //ust// consumed_new = consumed_old; //ust// break; //ust// } -//ust// } while (atomic_long_cmpxchg(&buf->consumed, consumed_old, +//ust// } while (uatomic_cmpxchg(&buf->consumed, consumed_old, //ust// consumed_new) != consumed_old); //ust// //ust// if (consumed_old != consumed_new) { @@ -1173,10 +1173,8 @@ static void ltt_relay_remove_channel(struct ust_channel *channel) //ust// * was either corrupted or not consumed (overwrite //ust// * mode). //ust// */ -//ust// local_add(offsets->reserve_commit_diff, -//ust// &buf->commit_count[ -//ust// SUBBUF_INDEX(offsets->begin, -//ust// buf->chan)]); +//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) { @@ -1188,7 +1186,7 @@ static void ltt_relay_remove_channel(struct ust_channel *channel) //ust// * recorder mode, we are skipping over a whole //ust// * subbuffer. //ust// */ -//ust// local_inc(&buf->corrupted_subbuffers); +//ust// uatomic_inc(&buf->corrupted_subbuffers); //ust// } //ust// } //ust// } @@ -1223,14 +1221,14 @@ static void ltt_relay_remove_channel(struct ust_channel *channel) //ust// * Perform retryable operations. //ust// */ //ust// if (ltt_nesting > 4) { -//ust// local_inc(&buf->events_lost); +//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 (local_cmpxchg(&buf->offset, offsets.old, +//ust// } while (uatomic_cmpxchg(&buf->offset, offsets.old, //ust// offsets.end) != offsets.old); //ust// //ust// /* @@ -1270,10 +1268,6 @@ static void ltt_relay_remove_channel(struct ust_channel *channel) //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// * Note, however, that as a local_cmpxchg is used for some atomic -//ust// * operations, this function must be called from the CPU which owns the buffer -//ust// * for a ACTIVE flush. //ust// */ //ust// static notrace void ltt_force_switch(struct ust_buffer *buf, //ust// enum force_switch_mode mode) @@ -1291,7 +1285,7 @@ static void ltt_relay_remove_channel(struct ust_channel *channel) //ust// do { //ust// if (ltt_relay_try_switch(mode, channel, buf, &offsets, &tsc)) //ust// return; -//ust// } while (local_cmpxchg(&buf->offset, offsets.old, +//ust// } while (uatomic_cmpxchg(&buf->offset, offsets.old, //ust// offsets.end) != offsets.old); //ust// //ust// /* @@ -1358,9 +1352,8 @@ static void ltt_reserve_switch_old_subbuf( * sent by get_subbuf() when it does its smp_rmb(). */ barrier(); - local_add(padding_size, - &buf->commit_count[oldidx].cc); - commit_count = local_read(&buf->commit_count[oldidx].cc); + 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); ltt_write_commit_counter(chan, buf, oldidx, offsets->old, commit_count, padding_size); @@ -1388,9 +1381,8 @@ static void ltt_reserve_switch_new_subbuf( * sent by get_subbuf() when it does its smp_rmb(). */ barrier(); - local_add(ltt_subbuffer_header_size(), - &buf->commit_count[beginidx].cc); - commit_count = local_read(&buf->commit_count[beginidx].cc); + 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 */ ltt_check_deliver(chan, buf, offsets->begin, commit_count, beginidx); ltt_write_commit_counter(chan, buf, beginidx, @@ -1434,9 +1426,8 @@ static void ltt_reserve_end_switch_current( * sent by get_subbuf() when it does its smp_rmb(). */ barrier(); - local_add(padding_size, - &buf->commit_count[endidx].cc); - commit_count = local_read(&buf->commit_count[endidx].cc); + uatomic_add(&buf->commit_count[endidx].cc, padding_size); + commit_count = uatomic_read(&buf->commit_count[endidx].cc); ltt_check_deliver(chan, buf, offsets->end - 1, commit_count, endidx); ltt_write_commit_counter(chan, buf, endidx, @@ -1458,7 +1449,7 @@ static int ltt_relay_try_switch_slow( long subbuf_index; long reserve_commit_diff; - offsets->begin = local_read(&buf->offset); + offsets->begin = uatomic_read(&buf->offset); offsets->old = offsets->begin; offsets->begin_switch = 0; offsets->end_switch_old = 0; @@ -1482,13 +1473,13 @@ static int ltt_relay_try_switch_slow( reserve_commit_diff = (BUFFER_TRUNC(offsets->begin, buf->chan) >> chan->n_subbufs_order) - - (local_read(&buf->commit_count[subbuf_index].cc_sb) + - (uatomic_read(&buf->commit_count[subbuf_index].cc_sb) & chan->commit_count_mask); if (reserve_commit_diff == 0) { /* Next buffer not corrupted. */ if (mode == FORCE_ACTIVE && !chan->overwrite - && offsets->begin - atomic_long_read(&buf->consumed) + && offsets->begin - uatomic_read(&buf->consumed) >= chan->alloc_size) { /* * We do not overwrite non consumed buffers and we are @@ -1510,10 +1501,6 @@ static int ltt_relay_try_switch_slow( * Force a sub-buffer switch for a per-cpu buffer. This operation is * completely reentrant : can be called while tracing is active with * absolutely no lock held. - * - * Note, however, that as a local_cmpxchg is used for some atomic - * operations, this function must be called from the CPU which owns the buffer - * for a ACTIVE flush. */ void ltt_force_switch_lockless_slow(struct ust_buffer *buf, enum force_switch_mode mode) @@ -1532,7 +1519,7 @@ void ltt_force_switch_lockless_slow(struct ust_buffer *buf, if (ltt_relay_try_switch_slow(mode, chan, buf, &offsets, &tsc)) return; - } while (local_cmpxchg(&buf->offset, offsets.old, + } while (uatomic_cmpxchg(&buf->offset, offsets.old, offsets.end) != offsets.old); /* @@ -1577,7 +1564,7 @@ static int ltt_relay_try_reserve_slow(struct ust_channel *chan, struct ust_buffe { long reserve_commit_diff; - offsets->begin = local_read(&buf->offset); + offsets->begin = uatomic_read(&buf->offset); offsets->old = offsets->begin; offsets->begin_switch = 0; offsets->end_switch_current = 0; @@ -1617,13 +1604,13 @@ static int ltt_relay_try_reserve_slow(struct ust_channel *chan, struct ust_buffe reserve_commit_diff = (BUFFER_TRUNC(offsets->begin, buf->chan) >> chan->n_subbufs_order) - - (local_read(&buf->commit_count[subbuf_index].cc_sb) + - (uatomic_read(&buf->commit_count[subbuf_index].cc_sb) & chan->commit_count_mask); if (likely(reserve_commit_diff == 0)) { /* Next buffer not corrupted. */ if (unlikely(!chan->overwrite && (SUBBUF_TRUNC(offsets->begin, buf->chan) - - SUBBUF_TRUNC(atomic_long_read( + - SUBBUF_TRUNC(uatomic_read( &buf->consumed), buf->chan)) >= chan->alloc_size)) { @@ -1631,7 +1618,7 @@ static int ltt_relay_try_reserve_slow(struct ust_channel *chan, struct ust_buffe * We do not overwrite non consumed buffers * and we are full : event is lost. */ - local_inc(&buf->events_lost); + uatomic_inc(&buf->events_lost); return -1; } else { /* @@ -1646,7 +1633,7 @@ static int ltt_relay_try_reserve_slow(struct ust_channel *chan, struct ust_buffe * overwrite mode. Caused by either a writer OOPS or * too many nested writes over a reserve/commit pair. */ - local_inc(&buf->events_lost); + uatomic_inc(&buf->events_lost); return -1; } offsets->size = ust_get_header_size(chan, @@ -1661,7 +1648,7 @@ static int ltt_relay_try_reserve_slow(struct ust_channel *chan, struct ust_buffe * Event too big for subbuffers, report error, don't * complete the sub-buffer switch. */ - local_inc(&buf->events_lost); + uatomic_inc(&buf->events_lost); return -1; } else { /* @@ -1715,7 +1702,7 @@ int ltt_reserve_slot_lockless_slow(struct ust_trace *trace, if (unlikely(ltt_relay_try_reserve_slow(chan, buf, &offsets, data_size, tsc, rflags, largest_align))) return -ENOSPC; - } while (unlikely(local_cmpxchg(&buf->offset, offsets.old, + } while (unlikely(uatomic_cmpxchg(&buf->offset, offsets.old, offsets.end) != offsets.old)); /* diff --git a/libust/buffers.h b/libust/buffers.h index a2f17a9..90ca5d9 100644 --- a/libust/buffers.h +++ b/libust/buffers.h @@ -42,28 +42,22 @@ /**************************************/ struct commit_counters { - local_t cc; - local_t cc_sb; /* Incremented _once_ at sb switch */ + long cc; /* ATOMIC */ + long cc_sb; /* ATOMIC - Incremented _once_ at sb switch */ }; struct ust_buffer { /* First 32 bytes cache-hot cacheline */ - local_t offset; /* Current offset in the buffer */ + long offset; /* Current offset in the buffer *atomic* */ struct commit_counters *commit_count; /* Commit count per sub-buffer */ - atomic_long_t consumed; /* - * Current offset in the buffer - * standard atomic access (shared) - */ + long consumed; /* Current offset in the buffer *atomic* access (shared) */ unsigned long last_tsc; /* * Last timestamp written in the buffer. */ /* End of first 32 bytes cacheline */ - atomic_long_t active_readers; /* - * Active readers count - * standard atomic access (shared) - */ - local_t events_lost; - local_t corrupted_subbuffers; + long active_readers; /* ATOMIC - Active readers count standard atomic access (shared) */ + long events_lost; /* ATOMIC */ + long corrupted_subbuffers; /* *ATOMIC* */ /* one byte is written to this pipe when data is available, in order to wake the consumer */ /* portability: Single byte writes must be as quick as possible. The kernel-side @@ -86,7 +80,7 @@ struct ust_buffer { unsigned int cpu; /* commit count per subbuffer; must be at end of struct */ - local_t commit_seq[0] ____cacheline_aligned; + long commit_seq[0] ____cacheline_aligned; /* ATOMIC */ } ____cacheline_aligned; /* @@ -184,7 +178,7 @@ static __inline__ void ltt_reserve_push_reader( long consumed_old, consumed_new; do { - consumed_old = atomic_long_read(&buf->consumed); + consumed_old = uatomic_read(&buf->consumed); /* * If buffer is in overwrite mode, push the reader consumed * count if the write position has reached it and we are not @@ -202,7 +196,7 @@ static __inline__ void ltt_reserve_push_reader( consumed_new = SUBBUF_ALIGN(consumed_old, buf->chan); else return; - } while (unlikely(atomic_long_cmpxchg(&buf->consumed, consumed_old, + } while (unlikely(uatomic_cmpxchg(&buf->consumed, consumed_old, consumed_new) != consumed_old)); } @@ -210,7 +204,7 @@ static __inline__ void ltt_vmcore_check_deliver( struct ust_buffer *buf, long commit_count, long idx) { - local_set(&buf->commit_seq[idx], commit_count); + uatomic_set(&buf->commit_seq[idx], commit_count); } static __inline__ void ltt_check_deliver(struct ust_channel *chan, @@ -230,7 +224,7 @@ static __inline__ void ltt_check_deliver(struct ust_channel *chan, * value without adding a add_return atomic operation to the * fast path. */ - if (likely(local_cmpxchg(&buf->commit_count[idx].cc_sb, + if (likely(uatomic_cmpxchg(&buf->commit_count[idx].cc_sb, old_commit_count, commit_count) == old_commit_count)) { int result; @@ -255,16 +249,16 @@ static __inline__ int ltt_poll_deliver(struct ust_channel *chan, struct ust_buff { long consumed_old, consumed_idx, commit_count, write_offset; - consumed_old = atomic_long_read(&buf->consumed); + consumed_old = uatomic_read(&buf->consumed); consumed_idx = SUBBUF_INDEX(consumed_old, buf->chan); - commit_count = local_read(&buf->commit_count[consumed_idx].cc_sb); + commit_count = uatomic_read(&buf->commit_count[consumed_idx].cc_sb); /* * No memory barrier here, since we are only interested * in a statistically correct polling result. The next poll will * get the data is we are racing. The mb() that ensures correct * memory order is in get_subbuf. */ - write_offset = local_read(&buf->offset); + write_offset = uatomic_read(&buf->offset); /* * Check that the subbuffer we are trying to consume has been @@ -302,7 +296,7 @@ static __inline__ int ltt_relay_try_reserve( long *o_begin, long *o_end, long *o_old, size_t *before_hdr_pad, size_t *size) { - *o_begin = local_read(&buf->offset); + *o_begin = uatomic_read(&buf->offset); *o_old = *o_begin; *tsc = trace_clock_read64(); @@ -358,7 +352,7 @@ static __inline__ int ltt_reserve_slot(struct ust_trace *trace, /* FIXME: make this rellay per cpu? */ if (unlikely(LOAD_SHARED(ltt_nesting) > 4)) { DBG("Dropping event because nesting is too deep."); - local_inc(&buf->events_lost); + uatomic_inc(&buf->events_lost); return -EPERM; } @@ -368,7 +362,7 @@ static __inline__ int ltt_reserve_slot(struct ust_trace *trace, &before_hdr_pad, slot_size))) goto slow_path; - if (unlikely(local_cmpxchg(&buf->offset, o_old, o_end) != o_old)) + if (unlikely(uatomic_cmpxchg(&buf->offset, o_old, o_end) != o_old)) goto slow_path; /* @@ -401,10 +395,6 @@ slow_path: * Force a sub-buffer switch for a per-cpu buffer. This operation is * completely reentrant : can be called while tracing is active with * absolutely no lock held. - * - * Note, however, that as a local_cmpxchg is used for some atomic - * operations, this function must be called from the CPU which owns the buffer - * for a ACTIVE flush. */ static __inline__ void ltt_force_switch(struct ust_buffer *buf, enum force_switch_mode mode) @@ -437,9 +427,9 @@ static __inline__ void ltt_write_commit_counter(struct ust_channel *chan, if (unlikely(SUBBUF_OFFSET(offset - commit_count, buf->chan))) return; - commit_seq_old = local_read(&buf->commit_seq[idx]); + commit_seq_old = uatomic_read(&buf->commit_seq[idx]); while (commit_seq_old < commit_count) - commit_seq_old = local_cmpxchg(&buf->commit_seq[idx], + commit_seq_old = uatomic_cmpxchg(&buf->commit_seq[idx], commit_seq_old, commit_count); DBG("commit_seq for channel %s_%d, subbuf %ld is now %ld", buf->chan->channel_name, buf->cpu, idx, commit_count); @@ -482,7 +472,7 @@ static __inline__ void ltt_commit_slot( */ barrier(); #endif - local_add(slot_size, &buf->commit_count[endidx].cc); + uatomic_add(&buf->commit_count[endidx].cc, slot_size); /* * commit count read can race with concurrent OOO commit count updates. * This is only needed for ltt_check_deliver (for non-polling delivery @@ -492,7 +482,7 @@ static __inline__ void ltt_commit_slot( * - Multiple delivery for the same sub-buffer (which is handled * gracefully by the reader code) if the value is for a full * sub-buffer. It's important that we can never miss a sub-buffer - * delivery. Re-reading the value after the local_add ensures this. + * delivery. Re-reading the value after the uatomic_add ensures this. * - Reading a commit_count with a higher value that what was actually * added to it for the ltt_write_commit_counter call (again caused by * a concurrent committer). It does not matter, because this function @@ -500,7 +490,7 @@ static __inline__ void ltt_commit_slot( * reserve offset for a specific sub-buffer, which is completely * independent of the order. */ - commit_count = local_read(&buf->commit_count[endidx].cc); + commit_count = uatomic_read(&buf->commit_count[endidx].cc); ltt_check_deliver(chan, buf, offset_end - 1, commit_count, endidx); /* diff --git a/libust/channels.c b/libust/channels.c index c90733c..b7f3543 100644 --- a/libust/channels.c +++ b/libust/channels.c @@ -72,8 +72,8 @@ static void release_channel_setting(struct kref *kref) struct ltt_channel_setting, kref); struct ltt_channel_setting *iter; - if (atomic_read(&index_kref.refcount) == 0 - && atomic_read(&setting->kref.refcount) == 0) { + if (uatomic_read(&index_kref.refcount) == 0 + && uatomic_read(&setting->kref.refcount) == 0) { list_del(&setting->list); kfree(setting); @@ -113,7 +113,7 @@ int ltt_channels_register(const char *name) mutex_lock(<t_channel_mutex); setting = lookup_channel(name); if (setting) { - if (atomic_read(&setting->kref.refcount) == 0) + if (uatomic_read(&setting->kref.refcount) == 0) goto init_kref; else { kref_get(&setting->kref); @@ -149,7 +149,7 @@ int ltt_channels_unregister(const char *name) mutex_lock(<t_channel_mutex); setting = lookup_channel(name); - if (!setting || atomic_read(&setting->kref.refcount) == 0) { + if (!setting || uatomic_read(&setting->kref.refcount) == 0) { ret = -ENOENT; goto end; } @@ -175,7 +175,7 @@ int ltt_channels_set_default(const char *name, mutex_lock(<t_channel_mutex); setting = lookup_channel(name); - if (!setting || atomic_read(&setting->kref.refcount) == 0) { + if (!setting || uatomic_read(&setting->kref.refcount) == 0) { ret = -ENOENT; goto end; } @@ -199,7 +199,7 @@ const char *ltt_channels_get_name_from_index(unsigned int index) struct ltt_channel_setting *iter; list_for_each_entry(iter, <t_channels, list) - if (iter->index == index && atomic_read(&iter->kref.refcount)) + if (iter->index == index && uatomic_read(&iter->kref.refcount)) return iter->name; return NULL; } @@ -212,7 +212,7 @@ ltt_channels_get_setting_from_name(const char *name) list_for_each_entry(iter, <t_channels, list) if (!strcmp(iter->name, name) - && atomic_read(&iter->kref.refcount)) + && uatomic_read(&iter->kref.refcount)) return iter; return NULL; } @@ -259,7 +259,7 @@ struct ust_channel *ltt_channels_trace_alloc(unsigned int *nr_channels, WARN("ltt_channels_trace_alloc: no free_index; are there any probes connected?"); goto end; } - if (!atomic_read(&index_kref.refcount)) + if (!uatomic_read(&index_kref.refcount)) kref_init(&index_kref); else kref_get(&index_kref); @@ -271,7 +271,7 @@ struct ust_channel *ltt_channels_trace_alloc(unsigned int *nr_channels, goto end; } list_for_each_entry(iter, <t_channels, list) { - if (!atomic_read(&iter->kref.refcount)) + if (!uatomic_read(&iter->kref.refcount)) continue; channel[iter->index].subbuf_size = iter->subbuf_size; channel[iter->index].subbuf_cnt = iter->subbuf_cnt; diff --git a/libust/tracectl.c b/libust/tracectl.c index 57218a6..25e9645 100644 --- a/libust/tracectl.c +++ b/libust/tracectl.c @@ -26,6 +26,7 @@ #include #include #include +#include #include #include @@ -684,7 +685,7 @@ static int do_cmd_get_subbuffer(const char *recvbuf, struct ustcomm_source *src) /* Being here is the proof the daemon has mapped the buffer in its * memory. We may now decrement buffers_to_export. */ - if(atomic_long_read(&buf->consumed) == 0) { + if(uatomic_read(&buf->consumed) == 0) { DBG("decrementing buffers_to_export"); buffers_to_export--; } diff --git a/ustd/lowlevel.c b/ustd/lowlevel.c index 4c179c5..57a9f66 100644 --- a/ustd/lowlevel.c +++ b/ustd/lowlevel.c @@ -65,8 +65,8 @@ void finish_consuming_dead_subbuffer(struct buffer_info *buf) { struct ust_buffer *ustbuf = buf->bufstruct_mem; - long write_offset = local_read(&ustbuf->offset); - long consumed_offset = atomic_long_read(&ustbuf->consumed); + long write_offset = uatomic_read(&ustbuf->offset); + long consumed_offset = uatomic_read(&ustbuf->consumed); long i_subbuf; @@ -95,7 +95,7 @@ void finish_consuming_dead_subbuffer(struct buffer_info *buf) void *tmp; /* commit_seq is the offset in the buffer of the end of the last sequential commit. * Bytes beyond this limit cannot be recovered. This is a free-running counter. */ - long commit_seq = local_read(&ustbuf->commit_seq[i_subbuf]); + long commit_seq = uatomic_read(&ustbuf->commit_seq[i_subbuf]); unsigned long valid_length = buf->subbuf_size; long n_subbufs_order = get_count_order(buf->n_subbufs);