X-Git-Url: http://git.efficios.com/?a=blobdiff_plain;f=src%2Flttng-events.c;h=34e5fe9d98e657aaba9de8cac0f250614b6eaff0;hb=2dfda770cc6781ec372ee8dadd8eb4f6ab37375a;hp=a85360912271c8725c4d59e329f4c3ea212ca6cf;hpb=cfa6cc1d0f01c2cfcc1a679abf3a6572d411c309;p=deliverable%2Flttng-modules.git diff --git a/src/lttng-events.c b/src/lttng-events.c index a8536091..34e5fe9d 100644 --- a/src/lttng-events.c +++ b/src/lttng-events.c @@ -55,9 +55,9 @@ static LIST_HEAD(lttng_transport_list); static DEFINE_MUTEX(sessions_mutex); static struct kmem_cache *event_cache; -static void lttng_session_lazy_sync_enablers(struct lttng_session *session); -static void lttng_session_sync_enablers(struct lttng_session *session); -static void lttng_enabler_destroy(struct lttng_enabler *enabler); +static void lttng_session_lazy_sync_event_enablers(struct lttng_session *session); +static void lttng_session_sync_event_enablers(struct lttng_session *session); +static void lttng_event_enabler_destroy(struct lttng_event_enabler *event_enabler); static void _lttng_event_destroy(struct lttng_event *event); static void _lttng_channel_destroy(struct lttng_channel *chan); @@ -191,7 +191,7 @@ void lttng_session_destroy(struct lttng_session *session) struct lttng_channel *chan, *tmpchan; struct lttng_event *event, *tmpevent; struct lttng_metadata_stream *metadata_stream; - struct lttng_enabler *enabler, *tmpenabler; + struct lttng_event_enabler *event_enabler, *tmp_event_enabler; int ret; mutex_lock(&sessions_mutex); @@ -205,17 +205,23 @@ void lttng_session_destroy(struct lttng_session *session) WARN_ON(ret); } synchronize_trace(); /* Wait for in-flight events to complete */ - list_for_each_entry_safe(enabler, tmpenabler, + list_for_each_entry(chan, &session->chan, list) { + ret = lttng_syscalls_destroy(chan); + WARN_ON(ret); + } + list_for_each_entry_safe(event_enabler, tmp_event_enabler, &session->enablers_head, node) - lttng_enabler_destroy(enabler); + lttng_event_enabler_destroy(event_enabler); list_for_each_entry_safe(event, tmpevent, &session->events, list) _lttng_event_destroy(event); list_for_each_entry_safe(chan, tmpchan, &session->chan, list) { BUG_ON(chan->channel_type == METADATA_CHANNEL); _lttng_channel_destroy(chan); } + mutex_lock(&session->metadata_cache->lock); list_for_each_entry(metadata_stream, &session->metadata_cache->metadata_stream, list) _lttng_metadata_channel_hangup(metadata_stream); + mutex_unlock(&session->metadata_cache->lock); lttng_id_tracker_destroy(&session->pid_tracker, false); lttng_id_tracker_destroy(&session->vpid_tracker, false); lttng_id_tracker_destroy(&session->uid_tracker, false); @@ -253,7 +259,7 @@ int lttng_session_enable(struct lttng_session *session) session->tstate = 1; /* We need to sync enablers with session before activation. */ - lttng_session_sync_enablers(session); + lttng_session_sync_event_enablers(session); /* * Snapshot the number of events per channel to know the type of header @@ -303,7 +309,7 @@ int lttng_session_disable(struct lttng_session *session) /* Set transient enabler state to "disabled" */ session->tstate = 0; - lttng_session_sync_enablers(session); + lttng_session_sync_event_enablers(session); /* Set each stream's quiescent state. */ list_for_each_entry(chan, &session->chan, list) { @@ -370,7 +376,7 @@ int lttng_channel_enable(struct lttng_channel *channel) } /* Set transient enabler state to "enabled" */ channel->tstate = 1; - lttng_session_sync_enablers(channel->session); + lttng_session_sync_event_enablers(channel->session); /* Set atomically the state to "enabled" */ WRITE_ONCE(channel->enabled, 1); end: @@ -395,7 +401,7 @@ int lttng_channel_disable(struct lttng_channel *channel) WRITE_ONCE(channel->enabled, 0); /* Set transient enabler state to "enabled" */ channel->tstate = 0; - lttng_session_sync_enablers(channel->session); + lttng_session_sync_event_enablers(channel->session); end: mutex_unlock(&sessions_mutex); return ret; @@ -500,12 +506,12 @@ struct lttng_channel *lttng_channel_create(struct lttng_session *session, goto active; /* Refuse to add channel to active session */ transport = lttng_transport_find(transport_name); if (!transport) { - printk(KERN_WARNING "LTTng transport %s not found\n", + printk(KERN_WARNING "LTTng: transport %s not found\n", transport_name); goto notransport; } if (!try_module_get(transport->owner)) { - printk(KERN_WARNING "LTT : Can't lock transport module.\n"); + printk(KERN_WARNING "LTTng: Can't lock transport module.\n"); goto notransport; } chan = kzalloc(sizeof(struct lttng_channel), GFP_KERNEL); @@ -742,6 +748,28 @@ struct lttng_event *_lttng_event_create(struct lttng_channel *chan, event->enabled = 0; event->registered = 0; event->desc = event_desc; + switch (event_param->u.syscall.entryexit) { + case LTTNG_KERNEL_SYSCALL_ENTRYEXIT: + ret = -EINVAL; + goto register_error; + case LTTNG_KERNEL_SYSCALL_ENTRY: + event->u.syscall.entryexit = LTTNG_SYSCALL_ENTRY; + break; + case LTTNG_KERNEL_SYSCALL_EXIT: + event->u.syscall.entryexit = LTTNG_SYSCALL_EXIT; + break; + } + switch (event_param->u.syscall.abi) { + case LTTNG_KERNEL_SYSCALL_ABI_ALL: + ret = -EINVAL; + goto register_error; + case LTTNG_KERNEL_SYSCALL_ABI_NATIVE: + event->u.syscall.abi = LTTNG_SYSCALL_ABI_NATIVE; + break; + case LTTNG_KERNEL_SYSCALL_ABI_COMPAT: + event->u.syscall.abi = LTTNG_SYSCALL_ABI_COMPAT; + break; + } if (!event->desc) { ret = -EINVAL; goto register_error; @@ -828,8 +856,7 @@ void register_event(struct lttng_event *event) event); break; case LTTNG_KERNEL_SYSCALL: - ret = lttng_syscall_filter_enable(event->chan, - desc->name); + ret = lttng_syscall_filter_enable(event->chan, event); break; case LTTNG_KERNEL_KPROBE: case LTTNG_KERNEL_UPROBE: @@ -872,8 +899,7 @@ int _lttng_event_unregister(struct lttng_event *event) ret = 0; break; case LTTNG_KERNEL_SYSCALL: - ret = lttng_syscall_filter_disable(event->chan, - desc->name); + ret = lttng_syscall_filter_disable(event->chan, event); break; case LTTNG_KERNEL_NOOP: ret = 0; @@ -1205,62 +1231,113 @@ int lttng_desc_match_enabler(const struct lttng_event_desc *desc, struct lttng_enabler *enabler) { const char *desc_name, *enabler_name; + bool compat = false, entry = false; enabler_name = enabler->event_param.name; switch (enabler->event_param.instrumentation) { case LTTNG_KERNEL_TRACEPOINT: desc_name = desc->name; + switch (enabler->format_type) { + case LTTNG_ENABLER_FORMAT_STAR_GLOB: + return lttng_match_enabler_star_glob(desc_name, enabler_name); + case LTTNG_ENABLER_FORMAT_NAME: + return lttng_match_enabler_name(desc_name, enabler_name); + default: + return -EINVAL; + } break; case LTTNG_KERNEL_SYSCALL: desc_name = desc->name; - if (!strncmp(desc_name, "compat_", strlen("compat_"))) + if (!strncmp(desc_name, "compat_", strlen("compat_"))) { desc_name += strlen("compat_"); + compat = true; + } if (!strncmp(desc_name, "syscall_exit_", strlen("syscall_exit_"))) { desc_name += strlen("syscall_exit_"); } else if (!strncmp(desc_name, "syscall_entry_", strlen("syscall_entry_"))) { desc_name += strlen("syscall_entry_"); + entry = true; } else { WARN_ON_ONCE(1); return -EINVAL; } + switch (enabler->event_param.u.syscall.entryexit) { + case LTTNG_KERNEL_SYSCALL_ENTRYEXIT: + break; + case LTTNG_KERNEL_SYSCALL_ENTRY: + if (!entry) + return 0; + break; + case LTTNG_KERNEL_SYSCALL_EXIT: + if (entry) + return 0; + break; + default: + return -EINVAL; + } + switch (enabler->event_param.u.syscall.abi) { + case LTTNG_KERNEL_SYSCALL_ABI_ALL: + break; + case LTTNG_KERNEL_SYSCALL_ABI_NATIVE: + if (compat) + return 0; + break; + case LTTNG_KERNEL_SYSCALL_ABI_COMPAT: + if (!compat) + return 0; + break; + default: + return -EINVAL; + } + switch (enabler->event_param.u.syscall.match) { + case LTTNG_SYSCALL_MATCH_NAME: + switch (enabler->format_type) { + case LTTNG_ENABLER_FORMAT_STAR_GLOB: + return lttng_match_enabler_star_glob(desc_name, enabler_name); + case LTTNG_ENABLER_FORMAT_NAME: + return lttng_match_enabler_name(desc_name, enabler_name); + default: + return -EINVAL; + } + break; + case LTTNG_SYSCALL_MATCH_NR: + return -EINVAL; /* Not implemented. */ + default: + return -EINVAL; + } break; default: WARN_ON_ONCE(1); return -EINVAL; } - switch (enabler->type) { - case LTTNG_ENABLER_STAR_GLOB: - return lttng_match_enabler_star_glob(desc_name, enabler_name); - case LTTNG_ENABLER_NAME: - return lttng_match_enabler_name(desc_name, enabler_name); - default: - return -EINVAL; - } } static -int lttng_event_match_enabler(struct lttng_event *event, - struct lttng_enabler *enabler) +int lttng_event_enabler_match_event(struct lttng_event_enabler *event_enabler, + struct lttng_event *event) { - if (enabler->event_param.instrumentation != event->instrumentation) + struct lttng_enabler *base_enabler = lttng_event_enabler_as_enabler( + event_enabler); + + if (base_enabler->event_param.instrumentation != event->instrumentation) return 0; - if (lttng_desc_match_enabler(event->desc, enabler) - && event->chan == enabler->chan) + if (lttng_desc_match_enabler(event->desc, base_enabler) + && event->chan == event_enabler->chan) return 1; else return 0; } static -struct lttng_enabler_ref *lttng_event_enabler_ref(struct lttng_event *event, +struct lttng_enabler_ref *lttng_enabler_ref( + struct list_head *enablers_ref_list, struct lttng_enabler *enabler) { struct lttng_enabler_ref *enabler_ref; - list_for_each_entry(enabler_ref, - &event->enablers_ref_head, node) { + list_for_each_entry(enabler_ref, enablers_ref_list, node) { if (enabler_ref->ref == enabler) return enabler_ref; } @@ -1268,9 +1345,9 @@ struct lttng_enabler_ref *lttng_event_enabler_ref(struct lttng_event *event, } static -void lttng_create_tracepoint_if_missing(struct lttng_enabler *enabler) +void lttng_create_tracepoint_event_if_missing(struct lttng_event_enabler *event_enabler) { - struct lttng_session *session = enabler->chan->session; + struct lttng_session *session = event_enabler->chan->session; struct lttng_probe_desc *probe_desc; const struct lttng_event_desc *desc; int i; @@ -1292,7 +1369,8 @@ void lttng_create_tracepoint_if_missing(struct lttng_enabler *enabler) struct lttng_event *event; desc = probe_desc->event_desc[i]; - if (!lttng_desc_match_enabler(desc, enabler)) + if (!lttng_desc_match_enabler(desc, + lttng_event_enabler_as_enabler(event_enabler))) continue; event_name = desc->name; name_len = strlen(event_name); @@ -1304,7 +1382,7 @@ void lttng_create_tracepoint_if_missing(struct lttng_enabler *enabler) head = &session->events_ht.table[hash & (LTTNG_EVENT_HT_SIZE - 1)]; lttng_hlist_for_each_entry(event, head, hlist) { if (event->desc == desc - && event->chan == enabler->chan) + && event->chan == event_enabler->chan) found = 1; } if (found) @@ -1314,11 +1392,11 @@ void lttng_create_tracepoint_if_missing(struct lttng_enabler *enabler) * We need to create an event for this * event probe. */ - event = _lttng_event_create(enabler->chan, + event = _lttng_event_create(event_enabler->chan, NULL, NULL, desc, LTTNG_KERNEL_TRACEPOINT); if (!event) { - printk(KERN_INFO "Unable to create event %s\n", + printk(KERN_INFO "LTTng: Unable to create event %s\n", probe_desc->event_desc[i]->name); } } @@ -1326,11 +1404,11 @@ void lttng_create_tracepoint_if_missing(struct lttng_enabler *enabler) } static -void lttng_create_syscall_if_missing(struct lttng_enabler *enabler) +void lttng_create_syscall_event_if_missing(struct lttng_event_enabler *event_enabler) { int ret; - ret = lttng_syscalls_register(enabler->chan, NULL); + ret = lttng_syscalls_register(event_enabler->chan, NULL); WARN_ON_ONCE(ret); } @@ -1340,14 +1418,14 @@ void lttng_create_syscall_if_missing(struct lttng_enabler *enabler) * Should be called with sessions mutex held. */ static -void lttng_create_event_if_missing(struct lttng_enabler *enabler) +void lttng_create_event_if_missing(struct lttng_event_enabler *event_enabler) { - switch (enabler->event_param.instrumentation) { + switch (event_enabler->base.event_param.instrumentation) { case LTTNG_KERNEL_TRACEPOINT: - lttng_create_tracepoint_if_missing(enabler); + lttng_create_tracepoint_event_if_missing(event_enabler); break; case LTTNG_KERNEL_SYSCALL: - lttng_create_syscall_if_missing(enabler); + lttng_create_syscall_event_if_missing(event_enabler); break; default: WARN_ON_ONCE(1); @@ -1356,35 +1434,49 @@ void lttng_create_event_if_missing(struct lttng_enabler *enabler) } /* - * Create events associated with an enabler (if not already present), + * Create events associated with an event_enabler (if not already present), * and add backward reference from the event to the enabler. * Should be called with sessions mutex held. */ static -int lttng_enabler_ref_events(struct lttng_enabler *enabler) +int lttng_event_enabler_ref_events(struct lttng_event_enabler *event_enabler) { - struct lttng_session *session = enabler->chan->session; + struct lttng_channel *chan = event_enabler->chan; + struct lttng_session *session = event_enabler->chan->session; + struct lttng_enabler *base_enabler = lttng_event_enabler_as_enabler(event_enabler); struct lttng_event *event; + if (base_enabler->event_param.instrumentation == LTTNG_KERNEL_SYSCALL && + base_enabler->event_param.u.syscall.entryexit == LTTNG_KERNEL_SYSCALL_ENTRYEXIT && + base_enabler->event_param.u.syscall.abi == LTTNG_KERNEL_SYSCALL_ABI_ALL && + base_enabler->event_param.u.syscall.match == LTTNG_SYSCALL_MATCH_NAME && + !strcmp(base_enabler->event_param.name, "*")) { + if (base_enabler->enabled) + WRITE_ONCE(chan->syscall_all, 1); + else + WRITE_ONCE(chan->syscall_all, 0); + } + /* First ensure that probe events are created for this enabler. */ - lttng_create_event_if_missing(enabler); + lttng_create_event_if_missing(event_enabler); - /* For each event matching enabler in session event list. */ + /* For each event matching event_enabler in session event list. */ list_for_each_entry(event, &session->events, list) { struct lttng_enabler_ref *enabler_ref; - if (!lttng_event_match_enabler(event, enabler)) + if (!lttng_event_enabler_match_event(event_enabler, event)) continue; - enabler_ref = lttng_event_enabler_ref(event, enabler); + enabler_ref = lttng_enabler_ref(&event->enablers_ref_head, + lttng_event_enabler_as_enabler(event_enabler)); if (!enabler_ref) { /* * If no backward ref, create it. - * Add backward ref from event to enabler. + * Add backward ref from event to event_enabler. */ enabler_ref = kzalloc(sizeof(*enabler_ref), GFP_KERNEL); if (!enabler_ref) return -ENOMEM; - enabler_ref->ref = enabler; + enabler_ref->ref = lttng_event_enabler_as_enabler(event_enabler); list_add(&enabler_ref->node, &event->enablers_ref_head); } @@ -1392,7 +1484,10 @@ int lttng_enabler_ref_events(struct lttng_enabler *enabler) /* * Link filter bytecodes if not linked yet. */ - lttng_enabler_event_link_bytecode(event, enabler); + lttng_enabler_link_bytecode(event->desc, + lttng_static_ctx, + &event->bytecode_runtime_head, + lttng_event_enabler_as_enabler(event_enabler)); /* TODO: merge event context. */ } @@ -1409,52 +1504,54 @@ int lttng_fix_pending_events(void) struct lttng_session *session; list_for_each_entry(session, &sessions, list) - lttng_session_lazy_sync_enablers(session); + lttng_session_lazy_sync_event_enablers(session); return 0; } -struct lttng_enabler *lttng_enabler_create(enum lttng_enabler_type type, +struct lttng_event_enabler *lttng_event_enabler_create( + enum lttng_enabler_format_type format_type, struct lttng_kernel_event *event_param, struct lttng_channel *chan) { - struct lttng_enabler *enabler; + struct lttng_event_enabler *event_enabler; - enabler = kzalloc(sizeof(*enabler), GFP_KERNEL); - if (!enabler) + event_enabler = kzalloc(sizeof(*event_enabler), GFP_KERNEL); + if (!event_enabler) return NULL; - enabler->type = type; - INIT_LIST_HEAD(&enabler->filter_bytecode_head); - memcpy(&enabler->event_param, event_param, - sizeof(enabler->event_param)); - enabler->chan = chan; + event_enabler->base.format_type = format_type; + INIT_LIST_HEAD(&event_enabler->base.filter_bytecode_head); + memcpy(&event_enabler->base.event_param, event_param, + sizeof(event_enabler->base.event_param)); + event_enabler->chan = chan; /* ctx left NULL */ - enabler->enabled = 0; - enabler->evtype = LTTNG_TYPE_ENABLER; + event_enabler->base.enabled = 0; + event_enabler->base.evtype = LTTNG_TYPE_ENABLER; mutex_lock(&sessions_mutex); - list_add(&enabler->node, &enabler->chan->session->enablers_head); - lttng_session_lazy_sync_enablers(enabler->chan->session); + list_add(&event_enabler->node, &event_enabler->chan->session->enablers_head); + lttng_session_lazy_sync_event_enablers(event_enabler->chan->session); mutex_unlock(&sessions_mutex); - return enabler; + return event_enabler; } -int lttng_enabler_enable(struct lttng_enabler *enabler) +int lttng_event_enabler_enable(struct lttng_event_enabler *event_enabler) { mutex_lock(&sessions_mutex); - enabler->enabled = 1; - lttng_session_lazy_sync_enablers(enabler->chan->session); + lttng_event_enabler_as_enabler(event_enabler)->enabled = 1; + lttng_session_lazy_sync_event_enablers(event_enabler->chan->session); mutex_unlock(&sessions_mutex); return 0; } -int lttng_enabler_disable(struct lttng_enabler *enabler) +int lttng_event_enabler_disable(struct lttng_event_enabler *event_enabler) { mutex_lock(&sessions_mutex); - enabler->enabled = 0; - lttng_session_lazy_sync_enablers(enabler->chan->session); + lttng_event_enabler_as_enabler(event_enabler)->enabled = 0; + lttng_session_lazy_sync_event_enablers(event_enabler->chan->session); mutex_unlock(&sessions_mutex); return 0; } +static int lttng_enabler_attach_bytecode(struct lttng_enabler *enabler, struct lttng_kernel_filter_bytecode __user *bytecode) { @@ -1473,11 +1570,12 @@ int lttng_enabler_attach_bytecode(struct lttng_enabler *enabler, sizeof(*bytecode) + bytecode_len); if (ret) goto error_free; + bytecode_node->enabler = enabler; /* Enforce length based on allocated size */ bytecode_node->bc.len = bytecode_len; list_add_tail(&bytecode_node->node, &enabler->filter_bytecode_head); - lttng_session_lazy_sync_enablers(enabler->chan->session); + return 0; error_free: @@ -1485,6 +1583,22 @@ error_free: return ret; } +int lttng_event_enabler_attach_bytecode(struct lttng_event_enabler *event_enabler, + struct lttng_kernel_filter_bytecode __user *bytecode) +{ + int ret; + ret = lttng_enabler_attach_bytecode( + lttng_event_enabler_as_enabler(event_enabler), bytecode); + if (ret) + goto error; + + lttng_session_lazy_sync_event_enablers(event_enabler->chan->session); + return 0; + +error: + return ret; +} + int lttng_event_add_callsite(struct lttng_event *event, struct lttng_kernel_event_callsite __user *callsite) { @@ -1497,7 +1611,7 @@ int lttng_event_add_callsite(struct lttng_event *event, } } -int lttng_enabler_attach_context(struct lttng_enabler *enabler, +int lttng_event_enabler_attach_context(struct lttng_event_enabler *event_enabler, struct lttng_kernel_context *context_param) { return -ENOSYS; @@ -1513,27 +1627,33 @@ void lttng_enabler_destroy(struct lttng_enabler *enabler) &enabler->filter_bytecode_head, node) { kfree(filter_node); } +} + +static +void lttng_event_enabler_destroy(struct lttng_event_enabler *event_enabler) +{ + lttng_enabler_destroy(lttng_event_enabler_as_enabler(event_enabler)); /* Destroy contexts */ - lttng_destroy_context(enabler->ctx); + lttng_destroy_context(event_enabler->ctx); - list_del(&enabler->node); - kfree(enabler); + list_del(&event_enabler->node); + kfree(event_enabler); } /* - * lttng_session_sync_enablers should be called just before starting a + * lttng_session_sync_event_enablers should be called just before starting a * session. * Should be called with sessions mutex held. */ static -void lttng_session_sync_enablers(struct lttng_session *session) +void lttng_session_sync_event_enablers(struct lttng_session *session) { - struct lttng_enabler *enabler; + struct lttng_event_enabler *event_enabler; struct lttng_event *event; - list_for_each_entry(enabler, &session->enablers_head, node) - lttng_enabler_ref_events(enabler); + list_for_each_entry(event_enabler, &session->enablers_head, node) + lttng_event_enabler_ref_events(event_enabler); /* * For each event, if at least one of its enablers is enabled, * and its channel and session transient states are enabled, we @@ -1605,12 +1725,12 @@ void lttng_session_sync_enablers(struct lttng_session *session) * Should be called with sessions mutex held. */ static -void lttng_session_lazy_sync_enablers(struct lttng_session *session) +void lttng_session_lazy_sync_event_enablers(struct lttng_session *session) { /* We can skip if session is not active */ if (!session->active) return; - lttng_session_sync_enablers(session); + lttng_session_sync_event_enablers(session); } /* @@ -1626,7 +1746,7 @@ void lttng_session_lazy_sync_enablers(struct lttng_session *session) * was written and a negative value on error. */ int lttng_metadata_output_channel(struct lttng_metadata_stream *stream, - struct channel *chan) + struct channel *chan, bool *coherent) { struct lib_ring_buffer_ctx ctx; int ret = 0; @@ -1665,6 +1785,7 @@ int lttng_metadata_output_channel(struct lttng_metadata_stream *stream, ret = stream->transport->ops.event_reserve(&ctx, 0); if (ret != 0) { printk(KERN_WARNING "LTTng: Metadata event reservation failed\n"); + stream->coherent = false; goto end; } stream->transport->ops.event_write(&ctx, @@ -1672,18 +1793,46 @@ int lttng_metadata_output_channel(struct lttng_metadata_stream *stream, reserve_len); stream->transport->ops.event_commit(&ctx); stream->metadata_in += reserve_len; + if (reserve_len < len) + stream->coherent = false; + else + stream->coherent = true; ret = reserve_len; end: + if (coherent) + *coherent = stream->coherent; mutex_unlock(&stream->metadata_cache->lock); return ret; } +static +void lttng_metadata_begin(struct lttng_session *session) +{ + if (atomic_inc_return(&session->metadata_cache->producing) == 1) + mutex_lock(&session->metadata_cache->lock); +} + +static +void lttng_metadata_end(struct lttng_session *session) +{ + WARN_ON_ONCE(!atomic_read(&session->metadata_cache->producing)); + if (atomic_dec_return(&session->metadata_cache->producing) == 0) { + struct lttng_metadata_stream *stream; + + list_for_each_entry(stream, &session->metadata_cache->metadata_stream, list) + wake_up_interruptible(&stream->read_wait); + mutex_unlock(&session->metadata_cache->lock); + } +} + /* * Write the metadata to the metadata cache. * Must be called with sessions_mutex held. * The metadata cache lock protects us from concurrent read access from * thread outputting metadata content to ring buffer. + * The content of the printf is printed as a single atomic metadata + * transaction. */ int lttng_metadata_printf(struct lttng_session *session, const char *fmt, ...) @@ -1691,9 +1840,8 @@ int lttng_metadata_printf(struct lttng_session *session, char *str; size_t len; va_list ap; - struct lttng_metadata_stream *stream; - WARN_ON_ONCE(!READ_ONCE(session->active)); + WARN_ON_ONCE(!LTTNG_READ_ONCE(session->active)); va_start(ap, fmt); str = kvasprintf(GFP_KERNEL, fmt, ap); @@ -1702,7 +1850,7 @@ int lttng_metadata_printf(struct lttng_session *session, return -ENOMEM; len = strlen(str); - mutex_lock(&session->metadata_cache->lock); + WARN_ON_ONCE(!atomic_read(&session->metadata_cache->producing)); if (session->metadata_cache->metadata_written + len > session->metadata_cache->cache_alloc) { char *tmp_cache_realloc; @@ -1728,16 +1876,11 @@ int lttng_metadata_printf(struct lttng_session *session, session->metadata_cache->metadata_written, str, len); session->metadata_cache->metadata_written += len; - mutex_unlock(&session->metadata_cache->lock); kfree(str); - list_for_each_entry(stream, &session->metadata_cache->metadata_stream, list) - wake_up_interruptible(&stream->read_wait); - return 0; err: - mutex_unlock(&session->metadata_cache->lock); kfree(str); return -ENOMEM; } @@ -2312,6 +2455,8 @@ int _lttng_fields_metadata_statedump(struct lttng_session *session, /* * Must be called with sessions_mutex held. + * The entire event metadata is printed as a single atomic metadata + * transaction. */ static int _lttng_event_metadata_statedump(struct lttng_session *session, @@ -2320,11 +2465,13 @@ int _lttng_event_metadata_statedump(struct lttng_session *session, { int ret = 0; - if (event->metadata_dumped || !READ_ONCE(session->active)) + if (event->metadata_dumped || !LTTNG_READ_ONCE(session->active)) return 0; if (chan->channel_type == METADATA_CHANNEL) return 0; + lttng_metadata_begin(session); + ret = lttng_metadata_printf(session, "event {\n" " name = \"%s\";\n" @@ -2374,12 +2521,15 @@ int _lttng_event_metadata_statedump(struct lttng_session *session, event->metadata_dumped = 1; end: + lttng_metadata_end(session); return ret; } /* * Must be called with sessions_mutex held. + * The entire channel metadata is printed as a single atomic metadata + * transaction. */ static int _lttng_channel_metadata_statedump(struct lttng_session *session, @@ -2387,12 +2537,14 @@ int _lttng_channel_metadata_statedump(struct lttng_session *session, { int ret = 0; - if (chan->metadata_dumped || !READ_ONCE(session->active)) + if (chan->metadata_dumped || !LTTNG_READ_ONCE(session->active)) return 0; if (chan->channel_type == METADATA_CHANNEL) return 0; + lttng_metadata_begin(session); + WARN_ON_ONCE(!chan->header_type); ret = lttng_metadata_printf(session, "stream {\n" @@ -2426,6 +2578,7 @@ int _lttng_channel_metadata_statedump(struct lttng_session *session, chan->metadata_dumped = 1; end: + lttng_metadata_end(session); return ret; } @@ -2611,8 +2764,11 @@ int _lttng_session_metadata_statedump(struct lttng_session *session) struct lttng_event *event; int ret = 0; - if (!READ_ONCE(session->active)) + if (!LTTNG_READ_ONCE(session->active)) return 0; + + lttng_metadata_begin(session); + if (session->metadata_dumped) goto skip_session; @@ -2785,6 +2941,7 @@ skip_session: } session->metadata_dumped = 1; end: + lttng_metadata_end(session); return ret; } @@ -3071,7 +3228,7 @@ static void __exit lttng_events_exit(void) module_exit(lttng_events_exit); -#include +#include #ifdef LTTNG_EXTRA_VERSION_GIT MODULE_INFO(extra_version_git, LTTNG_EXTRA_VERSION_GIT); #endif