X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=libringbuffer%2Fring_buffer_frontend.c;h=0996ecefc0313ff5ef8b955ce7dffd3a6a793849;hb=eddd8d5d1a04887d1979417f1aca6c2f109bfe50;hp=53d269d29644d9ef5578848f702099951b8fbd6a;hpb=45e9e6996ae8da8d5dfffbe9aebd8e0438a84124;p=lttng-ust.git diff --git a/libringbuffer/ring_buffer_frontend.c b/libringbuffer/ring_buffer_frontend.c index 53d269d2..0996ecef 100644 --- a/libringbuffer/ring_buffer_frontend.c +++ b/libringbuffer/ring_buffer_frontend.c @@ -38,15 +38,18 @@ * Dual LGPL v2.1/GPL v2 license. */ +#define _GNU_SOURCE #include #include #include #include #include #include +#include #include "smp.h" #include +#include "vatomic.h" #include "backend.h" #include "frontend.h" #include "shm.h" @@ -55,6 +58,9 @@ #define max(a, b) ((a) > (b) ? (a) : (b)) #endif +/* Print DBG() messages about events lost only every 1048576 hits */ +#define DBG_PRINT_NR_LOST (1UL << 20) + /* * Use POSIX SHM: shm_open(3) and shm_unlink(3). * close(2) to close the fd returned by shm_open. @@ -90,7 +96,8 @@ __thread unsigned int lib_ring_buffer_nesting; static void lib_ring_buffer_print_errors(struct channel *chan, struct lttng_ust_lib_ring_buffer *buf, int cpu, - struct lttng_ust_shm_handle *handle); + struct lttng_ust_shm_handle *handle) + __attribute__((unused)); /** * lib_ring_buffer_reset - Reset ring buffer to initial values. @@ -165,7 +172,7 @@ int lib_ring_buffer_create(struct lttng_ust_lib_ring_buffer *buf, struct channel *chan = caa_container_of(chanb, struct channel, backend); void *priv = channel_get_private(chan); size_t subbuf_header_size; - u64 tsc; + uint64_t tsc; int ret; /* Test for cpu hotplug */ @@ -418,7 +425,7 @@ struct lttng_ust_shm_handle *channel_create(const struct lttng_ust_lib_ring_buff void *buf_addr, size_t subbuf_size, size_t num_subbuf, unsigned int switch_timer_interval, unsigned int read_timer_interval, - int *shm_fd, int *wait_fd, uint64_t *memory_map_size) + int **shm_fd, int **wait_fd, uint64_t **memory_map_size) { int ret, cpu; size_t shmsize, chansize; @@ -608,8 +615,8 @@ struct lttng_ust_lib_ring_buffer *channel_get_ring_buffer( const struct lttng_ust_lib_ring_buffer_config *config, struct channel *chan, int cpu, struct lttng_ust_shm_handle *handle, - int *shm_fd, int *wait_fd, - uint64_t *memory_map_size) + int **shm_fd, int **wait_fd, + uint64_t **memory_map_size) { struct shm_ref *ref; @@ -944,12 +951,6 @@ void lib_ring_buffer_print_buffer_errors(struct lttng_ust_lib_ring_buffer *buf, const struct lttng_ust_lib_ring_buffer_config *config = &chan->backend.config; unsigned long write_offset, cons_offset; - /* - * Can be called in the error path of allocation when - * trans_channel_data is not yet set. - */ - if (!chan) - return; /* * No need to order commit_count, write_offset and cons_offset reads * because we execute at teardown when no more writer nor reader @@ -1009,7 +1010,7 @@ static void lib_ring_buffer_switch_old_start(struct lttng_ust_lib_ring_buffer *buf, struct channel *chan, struct switch_offsets *offsets, - u64 tsc, + uint64_t tsc, struct lttng_ust_shm_handle *handle) { const struct lttng_ust_lib_ring_buffer_config *config = &chan->backend.config; @@ -1047,7 +1048,7 @@ static void lib_ring_buffer_switch_old_end(struct lttng_ust_lib_ring_buffer *buf, struct channel *chan, struct switch_offsets *offsets, - u64 tsc, + uint64_t tsc, struct lttng_ust_shm_handle *handle) { const struct lttng_ust_lib_ring_buffer_config *config = &chan->backend.config; @@ -1084,7 +1085,7 @@ static void lib_ring_buffer_switch_new_start(struct lttng_ust_lib_ring_buffer *buf, struct channel *chan, struct switch_offsets *offsets, - u64 tsc, + uint64_t tsc, struct lttng_ust_shm_handle *handle) { const struct lttng_ust_lib_ring_buffer_config *config = &chan->backend.config; @@ -1120,7 +1121,7 @@ static void lib_ring_buffer_switch_new_end(struct lttng_ust_lib_ring_buffer *buf, struct channel *chan, struct switch_offsets *offsets, - u64 tsc, + uint64_t tsc, struct lttng_ust_shm_handle *handle) { const struct lttng_ust_lib_ring_buffer_config *config = &chan->backend.config; @@ -1156,7 +1157,7 @@ int lib_ring_buffer_try_switch_slow(enum switch_mode mode, struct lttng_ust_lib_ring_buffer *buf, struct channel *chan, struct switch_offsets *offsets, - u64 *tsc) + uint64_t *tsc) { const struct lttng_ust_lib_ring_buffer_config *config = &chan->backend.config; unsigned long off; @@ -1221,7 +1222,7 @@ void lib_ring_buffer_switch_slow(struct lttng_ust_lib_ring_buffer *buf, enum swi const struct lttng_ust_lib_ring_buffer_config *config = &chan->backend.config; struct switch_offsets offsets; unsigned long oldidx; - u64 tsc; + uint64_t tsc; offsets.size = 0; @@ -1338,11 +1339,19 @@ int lib_ring_buffer_try_reserve_slow(struct lttng_ust_lib_ring_buffer *buf, - subbuf_trunc((unsigned long) uatomic_read(&buf->consumed), chan) >= chan->backend.buf_size)) { + unsigned long nr_lost; + /* * We do not overwrite non consumed buffers * and we are full : record is lost. */ + nr_lost = v_read(config, &buf->records_lost_full); v_inc(config, &buf->records_lost_full); + if ((nr_lost & (DBG_PRINT_NR_LOST - 1)) == 0) { + DBG("%lu or more records lost in (%s:%d) (buffer full)\n", + nr_lost + 1, chan->backend.name, + buf->backend.cpu); + } return -ENOBUFS; } else { /* @@ -1353,13 +1362,21 @@ int lib_ring_buffer_try_reserve_slow(struct lttng_ust_lib_ring_buffer *buf, */ } } else { + unsigned long nr_lost; + /* * Next subbuffer reserve offset does not match the * commit offset. Drop record in producer-consumer and * overwrite mode. Caused by either a writer OOPS or too * many nested writes over a reserve/commit pair. */ + nr_lost = v_read(config, &buf->records_lost_wrap); v_inc(config, &buf->records_lost_wrap); + if ((nr_lost & (DBG_PRINT_NR_LOST - 1)) == 0) { + DBG("%lu or more records lost in (%s:%d) (wrap-around)\n", + nr_lost + 1, chan->backend.name, + buf->backend.cpu); + } return -EIO; } offsets->size = @@ -1373,11 +1390,20 @@ int lib_ring_buffer_try_reserve_slow(struct lttng_ust_lib_ring_buffer *buf, + ctx->data_size; if (caa_unlikely(subbuf_offset(offsets->begin, chan) + offsets->size > chan->backend.subbuf_size)) { + unsigned long nr_lost; + /* * Record too big for subbuffers, report error, don't * complete the sub-buffer switch. */ + nr_lost = v_read(config, &buf->records_lost_big); v_inc(config, &buf->records_lost_big); + if ((nr_lost & (DBG_PRINT_NR_LOST - 1)) == 0) { + DBG("%lu or more records lost in (%s:%d) record size " + " of %zu bytes is too large for buffer\n", + nr_lost + 1, chan->backend.name, + buf->backend.cpu, offsets->size); + } return -ENOSPC; } else { /*