X-Git-Url: https://git.lttng.org/?a=blobdiff_plain;f=libringbuffer%2Ffrontend_internal.h;h=dcf86b7736e8d2935b36baa6e89370b74a4cd272;hb=refs%2Fheads%2Flttng-ust-2.0;hp=73b44726df2fe9f1c4baaee731418e8fcead28f0;hpb=1d4981969313da002983ca979bd85c95493f7316;p=ust.git diff --git a/libringbuffer/frontend_internal.h b/libringbuffer/frontend_internal.h index 73b4472..dcf86b7 100644 --- a/libringbuffer/frontend_internal.h +++ b/libringbuffer/frontend_internal.h @@ -18,7 +18,7 @@ #include -#include +#include #include "backend_types.h" #include "frontend_types.h" #include "shm.h" @@ -85,8 +85,8 @@ unsigned long subbuf_index(unsigned long offset, struct channel *chan) #if (CAA_BITS_PER_LONG == 32) static inline -void save_last_tsc(const struct lib_ring_buffer_config *config, - struct lib_ring_buffer *buf, u64 tsc) +void save_last_tsc(const struct lttng_ust_lib_ring_buffer_config *config, + struct lttng_ust_lib_ring_buffer *buf, u64 tsc) { if (config->tsc_bits == 0 || config->tsc_bits == 64) return; @@ -98,8 +98,8 @@ void save_last_tsc(const struct lib_ring_buffer_config *config, } static inline -int last_tsc_overflow(const struct lib_ring_buffer_config *config, - struct lib_ring_buffer *buf, u64 tsc) +int last_tsc_overflow(const struct lttng_ust_lib_ring_buffer_config *config, + struct lttng_ust_lib_ring_buffer *buf, u64 tsc) { unsigned long tsc_shifted; @@ -107,7 +107,7 @@ int last_tsc_overflow(const struct lib_ring_buffer_config *config, return 0; tsc_shifted = (unsigned long)(tsc >> config->tsc_bits); - if (unlikely(tsc_shifted + if (caa_unlikely(tsc_shifted - (unsigned long)v_read(config, &buf->last_tsc))) return 1; else @@ -115,8 +115,8 @@ int last_tsc_overflow(const struct lib_ring_buffer_config *config, } #else static inline -void save_last_tsc(const struct lib_ring_buffer_config *config, - struct lib_ring_buffer *buf, u64 tsc) +void save_last_tsc(const struct lttng_ust_lib_ring_buffer_config *config, + struct lttng_ust_lib_ring_buffer *buf, u64 tsc) { if (config->tsc_bits == 0 || config->tsc_bits == 64) return; @@ -125,13 +125,13 @@ void save_last_tsc(const struct lib_ring_buffer_config *config, } static inline -int last_tsc_overflow(const struct lib_ring_buffer_config *config, - struct lib_ring_buffer *buf, u64 tsc) +int last_tsc_overflow(const struct lttng_ust_lib_ring_buffer_config *config, + struct lttng_ust_lib_ring_buffer *buf, u64 tsc) { if (config->tsc_bits == 0 || config->tsc_bits == 64) return 0; - if (unlikely((tsc - v_read(config, &buf->last_tsc)) + if (caa_unlikely((tsc - v_read(config, &buf->last_tsc)) >> config->tsc_bits)) return 1; else @@ -140,17 +140,17 @@ int last_tsc_overflow(const struct lib_ring_buffer_config *config, #endif extern -int lib_ring_buffer_reserve_slow(struct lib_ring_buffer_ctx *ctx); +int lib_ring_buffer_reserve_slow(struct lttng_ust_lib_ring_buffer_ctx *ctx); extern -void lib_ring_buffer_switch_slow(struct lib_ring_buffer *buf, +void lib_ring_buffer_switch_slow(struct lttng_ust_lib_ring_buffer *buf, enum switch_mode mode, - struct shm_handle *handle); + struct lttng_ust_shm_handle *handle); /* Buffer write helpers */ static inline -void lib_ring_buffer_reserve_push_reader(struct lib_ring_buffer *buf, +void lib_ring_buffer_reserve_push_reader(struct lttng_ust_lib_ring_buffer *buf, struct channel *chan, unsigned long offset) { @@ -167,38 +167,38 @@ void lib_ring_buffer_reserve_push_reader(struct lib_ring_buffer *buf, * write position sub-buffer index in the buffer being the one * which will win this loop. */ - if (unlikely(subbuf_trunc(offset, chan) + if (caa_unlikely(subbuf_trunc(offset, chan) - subbuf_trunc(consumed_old, chan) >= chan->backend.buf_size)) consumed_new = subbuf_align(consumed_old, chan); else return; - } while (unlikely(uatomic_cmpxchg(&buf->consumed, consumed_old, + } while (caa_unlikely(uatomic_cmpxchg(&buf->consumed, consumed_old, consumed_new) != consumed_old)); } static inline -void lib_ring_buffer_vmcore_check_deliver(const struct lib_ring_buffer_config *config, - struct lib_ring_buffer *buf, +void lib_ring_buffer_vmcore_check_deliver(const struct lttng_ust_lib_ring_buffer_config *config, + struct lttng_ust_lib_ring_buffer *buf, unsigned long commit_count, unsigned long idx, - struct shm_handle *handle) + struct lttng_ust_shm_handle *handle) { if (config->oops == RING_BUFFER_OOPS_CONSISTENCY) - v_set(config, &shmp(handle, buf->commit_hot)[idx].seq, commit_count); + v_set(config, &shmp_index(handle, buf->commit_hot, idx)->seq, commit_count); } static inline -int lib_ring_buffer_poll_deliver(const struct lib_ring_buffer_config *config, - struct lib_ring_buffer *buf, +int lib_ring_buffer_poll_deliver(const struct lttng_ust_lib_ring_buffer_config *config, + struct lttng_ust_lib_ring_buffer *buf, struct channel *chan, - struct shm_handle *handle) + struct lttng_ust_shm_handle *handle) { unsigned long consumed_old, consumed_idx, commit_count, write_offset; consumed_old = uatomic_read(&buf->consumed); consumed_idx = subbuf_index(consumed_old, chan); - commit_count = v_read(config, &shmp(handle, buf->commit_cold)[consumed_idx].cc_sb); + commit_count = v_read(config, &shmp_index(handle, buf->commit_cold, consumed_idx)->cc_sb); /* * No memory barrier here, since we are only interested * in a statistically correct polling result. The next poll will @@ -232,18 +232,18 @@ int lib_ring_buffer_poll_deliver(const struct lib_ring_buffer_config *config, } static inline -int lib_ring_buffer_pending_data(const struct lib_ring_buffer_config *config, - struct lib_ring_buffer *buf, +int lib_ring_buffer_pending_data(const struct lttng_ust_lib_ring_buffer_config *config, + struct lttng_ust_lib_ring_buffer *buf, struct channel *chan) { return !!subbuf_offset(v_read(config, &buf->offset), chan); } static inline -unsigned long lib_ring_buffer_get_data_size(const struct lib_ring_buffer_config *config, - struct lib_ring_buffer *buf, +unsigned long lib_ring_buffer_get_data_size(const struct lttng_ust_lib_ring_buffer_config *config, + struct lttng_ust_lib_ring_buffer *buf, unsigned long idx, - struct shm_handle *handle) + struct lttng_ust_shm_handle *handle) { return subbuffer_get_data_size(config, &buf->backend, idx, handle); } @@ -254,10 +254,10 @@ unsigned long lib_ring_buffer_get_data_size(const struct lib_ring_buffer_config * This is a very specific ftrace use-case, so we keep this as "internal" API. */ static inline -int lib_ring_buffer_reserve_committed(const struct lib_ring_buffer_config *config, - struct lib_ring_buffer *buf, +int lib_ring_buffer_reserve_committed(const struct lttng_ust_lib_ring_buffer_config *config, + struct lttng_ust_lib_ring_buffer *buf, struct channel *chan, - struct shm_handle *handle) + struct lttng_ust_shm_handle *handle) { unsigned long offset, idx, commit_count; @@ -275,7 +275,7 @@ int lib_ring_buffer_reserve_committed(const struct lib_ring_buffer_config *confi do { offset = v_read(config, &buf->offset); idx = subbuf_index(offset, chan); - commit_count = v_read(config, &shmp(handle, buf->commit_hot)[idx].cc); + commit_count = v_read(config, &shmp_index(handle, buf->commit_hot, idx)->cc); } while (offset != v_read(config, &buf->offset)); return ((buf_trunc(offset, chan) >> chan->backend.num_subbuf_order) @@ -283,20 +283,20 @@ int lib_ring_buffer_reserve_committed(const struct lib_ring_buffer_config *confi } static inline -void lib_ring_buffer_check_deliver(const struct lib_ring_buffer_config *config, - struct lib_ring_buffer *buf, +void lib_ring_buffer_check_deliver(const struct lttng_ust_lib_ring_buffer_config *config, + struct lttng_ust_lib_ring_buffer *buf, struct channel *chan, unsigned long offset, unsigned long commit_count, unsigned long idx, - struct shm_handle *handle) + struct lttng_ust_shm_handle *handle) { unsigned long old_commit_count = commit_count - chan->backend.subbuf_size; u64 tsc; /* Check if all commits have been done */ - if (unlikely((buf_trunc(offset, chan) >> chan->backend.num_subbuf_order) + if (caa_unlikely((buf_trunc(offset, chan) >> chan->backend.num_subbuf_order) - (old_commit_count & chan->commit_count_mask) == 0)) { /* * If we succeeded at updating cc_sb below, we are the subbuffer @@ -324,7 +324,7 @@ void lib_ring_buffer_check_deliver(const struct lib_ring_buffer_config *config, * The subbuffer size is least 2 bytes (minimum size: 1 page). * This guarantees that old_commit_count + 1 != commit_count. */ - if (likely(v_cmpxchg(config, &shmp(handle, buf->commit_cold)[idx].cc_sb, + if (caa_likely(v_cmpxchg(config, &shmp_index(handle, buf->commit_cold, idx)->cc_sb, old_commit_count, old_commit_count + 1) == old_commit_count)) { /* @@ -367,7 +367,7 @@ void lib_ring_buffer_check_deliver(const struct lib_ring_buffer_config *config, */ cmm_smp_mb(); /* End of exclusive subbuffer access */ - v_set(config, &shmp(handle, buf->commit_cold)[idx].cc_sb, + v_set(config, &shmp_index(handle, buf->commit_cold, idx)->cc_sb, commit_count); lib_ring_buffer_vmcore_check_deliver(config, buf, commit_count, idx, handle); @@ -376,10 +376,36 @@ void lib_ring_buffer_check_deliver(const struct lib_ring_buffer_config *config, * RING_BUFFER_WAKEUP_BY_WRITER wakeup is not lock-free. */ if (config->wakeup == RING_BUFFER_WAKEUP_BY_WRITER - && uatomic_read(&buf->active_readers) + && (uatomic_read(&buf->active_readers) + || uatomic_read(&buf->active_shadow_readers)) && lib_ring_buffer_poll_deliver(config, buf, chan, handle)) { - //wake_up_interruptible(&buf->read_wait); - //wake_up_interruptible(&chan->read_wait); + int wakeup_fd = shm_get_wakeup_fd(handle, &buf->self._ref); + + if (wakeup_fd >= 0) { + int ret; + /* + * Wake-up the other end by + * writing a null byte in the + * pipe (non-blocking). + * Important note: Because + * writing into the pipe is + * non-blocking (and therefore + * we allow dropping wakeup + * data, as long as there is + * wakeup data present in the + * pipe buffer to wake up the + * consumer), the consumer + * should perform the following + * sequence for waiting: + * 1) empty the pipe (reads). + * 2) check if there is data in + * the buffer. + * 3) wait on the pipe (poll). + */ + do { + ret = write(wakeup_fd, "", 1); + } while (ret == -1L && errno == EINTR); + } } } @@ -395,14 +421,14 @@ void lib_ring_buffer_check_deliver(const struct lib_ring_buffer_config *config, * useful for crash dump. */ static inline -void lib_ring_buffer_write_commit_counter(const struct lib_ring_buffer_config *config, - struct lib_ring_buffer *buf, +void lib_ring_buffer_write_commit_counter(const struct lttng_ust_lib_ring_buffer_config *config, + struct lttng_ust_lib_ring_buffer *buf, struct channel *chan, unsigned long idx, unsigned long buf_offset, unsigned long commit_count, size_t slot_size, - struct shm_handle *handle) + struct lttng_ust_shm_handle *handle) { unsigned long offset, commit_seq_old; @@ -417,21 +443,21 @@ void lib_ring_buffer_write_commit_counter(const struct lib_ring_buffer_config *c * buffer full/empty mismatch because offset is never zero here * (subbuffer header and record headers have non-zero length). */ - if (unlikely(subbuf_offset(offset - commit_count, chan))) + if (caa_unlikely(subbuf_offset(offset - commit_count, chan))) return; - commit_seq_old = v_read(config, &shmp(handle, buf->commit_hot)[idx].seq); + commit_seq_old = v_read(config, &shmp_index(handle, buf->commit_hot, idx)->seq); while ((long) (commit_seq_old - commit_count) < 0) - commit_seq_old = v_cmpxchg(config, &shmp(handle, buf->commit_hot)[idx].seq, + commit_seq_old = v_cmpxchg(config, &shmp_index(handle, buf->commit_hot, idx)->seq, commit_seq_old, commit_count); } -extern int lib_ring_buffer_create(struct lib_ring_buffer *buf, +extern int lib_ring_buffer_create(struct lttng_ust_lib_ring_buffer *buf, struct channel_backend *chanb, int cpu, - struct shm_handle *handle, + struct lttng_ust_shm_handle *handle, struct shm_object *shmobj); -extern void lib_ring_buffer_free(struct lib_ring_buffer *buf, - struct shm_handle *handle); +extern void lib_ring_buffer_free(struct lttng_ust_lib_ring_buffer *buf, + struct lttng_ust_shm_handle *handle); /* Keep track of trap nesting inside ring buffer code */ extern __thread unsigned int lib_ring_buffer_nesting;