X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=libringbuffer%2Ffrontend_api.h;h=77a269184fcf1f3dbc26380f7e2e201cd25bd497;hb=36cb884cbb186c5b280f3427066294a2350a944a;hp=6a06bba2c2393ba139bc506a8f88bb4027b59ea9;hpb=e92f3e285939848f248af08f11a39a04a7fcf852;p=lttng-ust.git diff --git a/libringbuffer/frontend_api.h b/libringbuffer/frontend_api.h index 6a06bba2..77a26918 100644 --- a/libringbuffer/frontend_api.h +++ b/libringbuffer/frontend_api.h @@ -37,10 +37,10 @@ /** * lib_ring_buffer_get_cpu - Precedes ring buffer reserve/commit. * - * Grabs RCU read-side lock and keeps a ring buffer nesting count as - * supplementary safety net to ensure tracer client code will never - * trigger an endless recursion. Returns the processor ID on success, - * -EPERM on failure (nesting count too high). + * Keeps a ring buffer nesting count as supplementary safety net to + * ensure tracer client code will never trigger an endless recursion. + * Returns the processor ID on success, -EPERM on failure (nesting count + * too high). * * asm volatile and "memory" clobber prevent the compiler from moving * instructions out of the ring buffer nesting count. This is required to ensure @@ -53,14 +53,13 @@ int lib_ring_buffer_get_cpu(const struct lttng_ust_lib_ring_buffer_config *confi { int cpu, nesting; - rcu_read_lock(); cpu = lttng_ust_get_cpu(); - nesting = ++lib_ring_buffer_nesting; /* TLS */ + nesting = ++URCU_TLS(lib_ring_buffer_nesting); cmm_barrier(); if (caa_unlikely(nesting > 4)) { WARN_ON_ONCE(1); - lib_ring_buffer_nesting--; /* TLS */ + URCU_TLS(lib_ring_buffer_nesting)--; rcu_read_unlock(); return -EPERM; } else @@ -74,8 +73,7 @@ static inline void lib_ring_buffer_put_cpu(const struct lttng_ust_lib_ring_buffer_config *config) { cmm_barrier(); - lib_ring_buffer_nesting--; /* TLS */ - rcu_read_unlock(); + URCU_TLS(lib_ring_buffer_nesting)--; /* TLS */ } /* @@ -288,14 +286,13 @@ void lib_ring_buffer_commit(const struct lttng_ust_lib_ring_buffer_config *confi commit_count = v_read(config, &shmp_index(handle, buf->commit_hot, endidx)->cc); lib_ring_buffer_check_deliver(config, buf, chan, offset_end - 1, - commit_count, endidx, handle); + commit_count, endidx, handle, ctx->tsc); /* * Update used size at each commit. It's needed only for extracting * ring_buffer buffers from vmcore, after crash. */ lib_ring_buffer_write_commit_counter(config, buf, chan, endidx, - ctx->buf_offset, commit_count, - ctx->slot_size, handle); + offset_end, commit_count, handle); } /**