From 5408b6d6a918704988b794885be7004117770a34 Mon Sep 17 00:00:00 2001 From: Mathieu Desnoyers Date: Fri, 5 Nov 2021 12:20:56 -0400 Subject: [PATCH] Refactoring: introduce lttng_syscall_event_enabler_create_event Signed-off-by: Mathieu Desnoyers Change-Id: Ifc230027ad2bfab1da580965ce8ecc9ff0150a78 --- src/lttng-syscalls.c | 310 +++++++++++++++++-------------------------- 1 file changed, 125 insertions(+), 185 deletions(-) diff --git a/src/lttng-syscalls.c b/src/lttng-syscalls.c index b93fbbfd..b9ae5e3a 100644 --- a/src/lttng-syscalls.c +++ b/src/lttng-syscalls.c @@ -527,25 +527,127 @@ struct lttng_kernel_syscall_table *get_syscall_table_from_event(struct lttng_ker } } +static +void lttng_syscall_event_enabler_create_event(struct lttng_event_enabler_common *syscall_event_enabler, + const struct lttng_kernel_event_desc *desc, struct hlist_head *dispatch_table, + enum sc_type type, unsigned int syscall_nr) +{ + struct lttng_kernel_event_common *event; + + switch (syscall_event_enabler->enabler_type) { + case LTTNG_EVENT_ENABLER_TYPE_RECORDER: + { + struct lttng_event_recorder_enabler *syscall_event_recorder_enabler = + container_of(syscall_event_enabler, struct lttng_event_recorder_enabler, parent); + struct lttng_event_recorder_enabler *event_recorder_enabler; + struct lttng_kernel_abi_event ev; + + /* We need to create an event for this syscall/enabler. */ + memset(&ev, 0, sizeof(ev)); + switch (type) { + case SC_TYPE_ENTRY: + ev.u.syscall.entryexit = LTTNG_KERNEL_ABI_SYSCALL_ENTRY; + ev.u.syscall.abi = LTTNG_KERNEL_ABI_SYSCALL_ABI_NATIVE; + break; + case SC_TYPE_EXIT: + ev.u.syscall.entryexit = LTTNG_KERNEL_ABI_SYSCALL_EXIT; + ev.u.syscall.abi = LTTNG_KERNEL_ABI_SYSCALL_ABI_NATIVE; + break; + case SC_TYPE_COMPAT_ENTRY: + ev.u.syscall.entryexit = LTTNG_KERNEL_ABI_SYSCALL_ENTRY; + ev.u.syscall.abi = LTTNG_KERNEL_ABI_SYSCALL_ABI_COMPAT; + break; + case SC_TYPE_COMPAT_EXIT: + ev.u.syscall.entryexit = LTTNG_KERNEL_ABI_SYSCALL_EXIT; + ev.u.syscall.abi = LTTNG_KERNEL_ABI_SYSCALL_ABI_COMPAT; + break; + } + strncpy(ev.name, desc->event_name, LTTNG_KERNEL_ABI_SYM_NAME_LEN - 1); + ev.name[LTTNG_KERNEL_ABI_SYM_NAME_LEN - 1] = '\0'; + ev.instrumentation = LTTNG_KERNEL_ABI_SYSCALL; + event_recorder_enabler = lttng_event_recorder_enabler_create(LTTNG_ENABLER_FORMAT_NAME, &ev, + syscall_event_recorder_enabler->chan); + WARN_ON_ONCE(!event_recorder_enabler); + if (!event_recorder_enabler) + return; + event = _lttng_kernel_event_create(&event_recorder_enabler->parent, desc); + WARN_ON_ONCE(!event || IS_ERR(event)); + lttng_event_enabler_destroy(&event_recorder_enabler->parent); + if (!event || IS_ERR(event)) { + printk(KERN_INFO "Unable to create event recorder %s\n", desc->event_name); + return; + } + hlist_add_head(&event->priv->u.syscall.node, &dispatch_table[syscall_nr]); + break; + } + case LTTNG_EVENT_ENABLER_TYPE_NOTIFIER: + { + struct lttng_event_notifier_enabler *syscall_event_notifier_enabler = + container_of(syscall_event_enabler, struct lttng_event_notifier_enabler, parent); + struct lttng_event_notifier_enabler *event_notifier_enabler; + struct lttng_kernel_abi_event_notifier event_notifier_param; + uint64_t user_token = syscall_event_enabler->user_token; + uint64_t error_counter_index = syscall_event_notifier_enabler->error_counter_index; + + memset(&event_notifier_param, 0, sizeof(event_notifier_param)); + switch (type) { + case SC_TYPE_ENTRY: + event_notifier_param.event.u.syscall.entryexit = LTTNG_KERNEL_ABI_SYSCALL_ENTRY; + event_notifier_param.event.u.syscall.abi = LTTNG_KERNEL_ABI_SYSCALL_ABI_NATIVE; + break; + case SC_TYPE_EXIT: + event_notifier_param.event.u.syscall.entryexit = LTTNG_KERNEL_ABI_SYSCALL_EXIT; + event_notifier_param.event.u.syscall.abi = LTTNG_KERNEL_ABI_SYSCALL_ABI_NATIVE; + break; + case SC_TYPE_COMPAT_ENTRY: + event_notifier_param.event.u.syscall.entryexit = LTTNG_KERNEL_ABI_SYSCALL_ENTRY; + event_notifier_param.event.u.syscall.abi = LTTNG_KERNEL_ABI_SYSCALL_ABI_COMPAT; + break; + case SC_TYPE_COMPAT_EXIT: + event_notifier_param.event.u.syscall.entryexit = LTTNG_KERNEL_ABI_SYSCALL_EXIT; + event_notifier_param.event.u.syscall.abi = LTTNG_KERNEL_ABI_SYSCALL_ABI_COMPAT; + break; + } + strncat(event_notifier_param.event.name, desc->event_name, + LTTNG_KERNEL_ABI_SYM_NAME_LEN - strlen(event_notifier_param.event.name) - 1); + event_notifier_param.event.name[LTTNG_KERNEL_ABI_SYM_NAME_LEN - 1] = '\0'; + event_notifier_param.event.instrumentation = LTTNG_KERNEL_ABI_SYSCALL; + event_notifier_param.event.token = user_token; + event_notifier_param.error_counter_index = error_counter_index; + + event_notifier_enabler = lttng_event_notifier_enabler_create(LTTNG_ENABLER_FORMAT_NAME, + &event_notifier_param, syscall_event_notifier_enabler->group); + WARN_ON_ONCE(!event_notifier_enabler); + event = _lttng_kernel_event_create(&event_notifier_enabler->parent, desc); + WARN_ON_ONCE(!event || IS_ERR(event)); + lttng_event_enabler_destroy(&event_notifier_enabler->parent); + if (!event || IS_ERR(event)) { + printk(KERN_INFO "Unable to create event notifier %s\n", desc->event_name); + return; + } + event->priv->u.syscall.syscall_id = syscall_nr; + break; + } + default: + break; + } +} + /* * noinline to diminish caller stack size. * Should be called with sessions lock held. */ static int lttng_create_syscall_event_if_missing(const struct trace_syscall_entry *table, size_t table_len, - struct hlist_head *chan_table, struct lttng_event_recorder_enabler *syscall_event_enabler, + struct hlist_head *dispatch_table, struct lttng_event_recorder_enabler *syscall_event_enabler, enum sc_type type) { struct lttng_event_ht *events_ht = lttng_get_event_ht_from_enabler(&syscall_event_enabler->parent); - struct lttng_kernel_channel_buffer *chan = syscall_event_enabler->chan; unsigned int i; /* Allocate events for each syscall matching enabler, insert into table */ for (i = 0; i < table_len; i++) { const struct lttng_kernel_event_desc *desc = table[i].desc; - struct lttng_event_recorder_enabler *event_enabler; - struct lttng_kernel_abi_event ev; - struct lttng_kernel_event_common *event; struct lttng_kernel_event_common_private *event_priv; struct hlist_head *head; bool found = false; @@ -568,46 +670,7 @@ int lttng_create_syscall_event_if_missing(const struct trace_syscall_entry *tabl if (found) continue; - /* We need to create an event for this syscall/enabler. */ - memset(&ev, 0, sizeof(ev)); - switch (type) { - case SC_TYPE_ENTRY: - ev.u.syscall.entryexit = LTTNG_KERNEL_ABI_SYSCALL_ENTRY; - ev.u.syscall.abi = LTTNG_KERNEL_ABI_SYSCALL_ABI_NATIVE; - break; - case SC_TYPE_EXIT: - ev.u.syscall.entryexit = LTTNG_KERNEL_ABI_SYSCALL_EXIT; - ev.u.syscall.abi = LTTNG_KERNEL_ABI_SYSCALL_ABI_NATIVE; - break; - case SC_TYPE_COMPAT_ENTRY: - ev.u.syscall.entryexit = LTTNG_KERNEL_ABI_SYSCALL_ENTRY; - ev.u.syscall.abi = LTTNG_KERNEL_ABI_SYSCALL_ABI_COMPAT; - break; - case SC_TYPE_COMPAT_EXIT: - ev.u.syscall.entryexit = LTTNG_KERNEL_ABI_SYSCALL_EXIT; - ev.u.syscall.abi = LTTNG_KERNEL_ABI_SYSCALL_ABI_COMPAT; - break; - } - strncpy(ev.name, desc->event_name, LTTNG_KERNEL_ABI_SYM_NAME_LEN - 1); - ev.name[LTTNG_KERNEL_ABI_SYM_NAME_LEN - 1] = '\0'; - ev.instrumentation = LTTNG_KERNEL_ABI_SYSCALL; - event_enabler = lttng_event_recorder_enabler_create(LTTNG_ENABLER_FORMAT_NAME, &ev, chan); - if (!event_enabler) { - return -ENOMEM; - } - event = _lttng_kernel_event_create(&event_enabler->parent, desc); - WARN_ON_ONCE(!event); - lttng_event_enabler_destroy(&event_enabler->parent); - if (IS_ERR(event)) { - /* - * If something goes wrong in event registration - * after the first one, we have no choice but to - * leave the previous events in there, until - * deleted by session teardown. - */ - return PTR_ERR(event); - } - hlist_add_head(&event->priv->u.syscall.node, &chan_table[i]); + lttng_syscall_event_enabler_create_event(&syscall_event_enabler->parent, desc, dispatch_table, type, i); } return 0; } @@ -822,55 +885,37 @@ int lttng_event_enabler_create_syscall_events_if_missing(struct lttng_event_enab } static -int create_unknown_event_notifier( +void create_unknown_event_notifier( struct lttng_event_notifier_enabler *event_notifier_enabler, enum sc_type type) { + struct lttng_kernel_syscall_table *syscall_table = get_syscall_table_from_enabler(&event_notifier_enabler->parent); struct lttng_event_ht *events_ht = lttng_get_event_ht_from_enabler(&event_notifier_enabler->parent); struct lttng_kernel_event_common_private *event_priv; - struct lttng_kernel_event_common *event; const struct lttng_kernel_event_desc *desc; - struct lttng_event_notifier_group *group = event_notifier_enabler->group; - struct lttng_kernel_syscall_table *syscall_table = &group->syscall_table; - struct lttng_kernel_abi_event_notifier event_notifier_param; - uint64_t user_token = event_notifier_enabler->parent.user_token; - uint64_t error_counter_index = event_notifier_enabler->error_counter_index; - struct lttng_event_enabler_common *base_enabler = lttng_event_notifier_enabler_as_enabler( - event_notifier_enabler); struct hlist_head *unknown_dispatch_list; - int ret = 0; bool found = false; - enum lttng_kernel_abi_syscall_abi abi; - enum lttng_kernel_abi_syscall_entryexit entryexit; struct hlist_head *head; switch (type) { case SC_TYPE_ENTRY: desc = &__event_desc___syscall_entry_unknown; unknown_dispatch_list = &syscall_table->unknown_syscall_dispatch; - entryexit = LTTNG_KERNEL_ABI_SYSCALL_ENTRY; - abi = LTTNG_KERNEL_ABI_SYSCALL_ABI_NATIVE; break; case SC_TYPE_EXIT: desc = &__event_desc___syscall_exit_unknown; unknown_dispatch_list = &syscall_table->unknown_syscall_exit_dispatch; - entryexit = LTTNG_KERNEL_ABI_SYSCALL_EXIT; - abi = LTTNG_KERNEL_ABI_SYSCALL_ABI_NATIVE; break; case SC_TYPE_COMPAT_ENTRY: desc = &__event_desc___compat_syscall_entry_unknown; unknown_dispatch_list = &syscall_table->compat_unknown_syscall_dispatch; - entryexit = LTTNG_KERNEL_ABI_SYSCALL_ENTRY; - abi = LTTNG_KERNEL_ABI_SYSCALL_ABI_COMPAT; break; case SC_TYPE_COMPAT_EXIT: desc = &__event_desc___compat_syscall_exit_unknown; unknown_dispatch_list = &syscall_table->compat_unknown_syscall_exit_dispatch; - entryexit = LTTNG_KERNEL_ABI_SYSCALL_EXIT; - abi = LTTNG_KERNEL_ABI_SYSCALL_ABI_COMPAT; break; default: - BUG_ON(1); + WARN_ON_ONCE(1); } /* @@ -878,61 +923,26 @@ int create_unknown_event_notifier( */ head = utils_borrow_hash_table_bucket(events_ht->table, LTTNG_EVENT_HT_SIZE, desc->event_name); lttng_hlist_for_each_entry(event_priv, head, hlist_node) { - if (lttng_event_enabler_desc_match_event(base_enabler, desc, event_priv->pub)) + if (lttng_event_enabler_desc_match_event(&event_notifier_enabler->parent, desc, event_priv->pub)) found = true; } - if (found) - goto end; - - memset(&event_notifier_param, 0, sizeof(event_notifier_param)); - strncat(event_notifier_param.event.name, desc->event_name, - LTTNG_KERNEL_ABI_SYM_NAME_LEN - strlen(event_notifier_param.event.name) - 1); - - event_notifier_param.event.name[LTTNG_KERNEL_ABI_SYM_NAME_LEN - 1] = '\0'; - - event_notifier_param.event.instrumentation = LTTNG_KERNEL_ABI_SYSCALL; - event_notifier_param.event.token = user_token; - event_notifier_param.event.u.syscall.abi = abi; - event_notifier_param.event.u.syscall.entryexit = entryexit; - event_notifier_param.error_counter_index = error_counter_index; - - event_notifier_enabler = lttng_event_notifier_enabler_create(LTTNG_ENABLER_FORMAT_NAME, - &event_notifier_param, group); - WARN_ON_ONCE(!event_notifier_enabler); - event = _lttng_kernel_event_create(&event_notifier_enabler->parent, desc); - lttng_event_enabler_destroy(&event_notifier_enabler->parent); - if (IS_ERR(event)) { - printk(KERN_INFO "Unable to create unknown notifier %s\n", - desc->event_name); - ret = -ENOMEM; - goto end; - } - - hlist_add_head_rcu(&event->priv->u.syscall.node, unknown_dispatch_list); - -end: - return ret; + if (!found) + lttng_syscall_event_enabler_create_event(&event_notifier_enabler->parent, desc, unknown_dispatch_list, type, -1U); } -static int create_matching_event_notifiers( +static +void create_matching_event_notifiers( struct lttng_event_notifier_enabler *syscall_event_notifier_enabler, const struct trace_syscall_entry *table, size_t table_len, enum sc_type type) { struct lttng_event_ht *events_ht = lttng_get_event_ht_from_enabler(&syscall_event_notifier_enabler->parent); - struct lttng_event_notifier_group *group = syscall_event_notifier_enabler->group; const struct lttng_kernel_event_desc *desc; - uint64_t user_token = syscall_event_notifier_enabler->parent.user_token; - uint64_t error_counter_index = syscall_event_notifier_enabler->error_counter_index; unsigned int i; - int ret = 0; /* iterate over all syscall and create event_notifier that match */ for (i = 0; i < table_len; i++) { - struct lttng_event_notifier_enabler *event_notifier_enabler; struct lttng_kernel_event_common_private *event_priv; - struct lttng_kernel_event_common *event; - struct lttng_kernel_abi_event_notifier event_notifier_param; struct hlist_head *head; int found = 0; @@ -957,50 +967,8 @@ static int create_matching_event_notifiers( if (found) continue; - memset(&event_notifier_param, 0, sizeof(event_notifier_param)); - switch (type) { - case SC_TYPE_ENTRY: - event_notifier_param.event.u.syscall.entryexit = LTTNG_KERNEL_ABI_SYSCALL_ENTRY; - event_notifier_param.event.u.syscall.abi = LTTNG_KERNEL_ABI_SYSCALL_ABI_NATIVE; - break; - case SC_TYPE_EXIT: - event_notifier_param.event.u.syscall.entryexit = LTTNG_KERNEL_ABI_SYSCALL_EXIT; - event_notifier_param.event.u.syscall.abi = LTTNG_KERNEL_ABI_SYSCALL_ABI_NATIVE; - break; - case SC_TYPE_COMPAT_ENTRY: - event_notifier_param.event.u.syscall.entryexit = LTTNG_KERNEL_ABI_SYSCALL_ENTRY; - event_notifier_param.event.u.syscall.abi = LTTNG_KERNEL_ABI_SYSCALL_ABI_COMPAT; - break; - case SC_TYPE_COMPAT_EXIT: - event_notifier_param.event.u.syscall.entryexit = LTTNG_KERNEL_ABI_SYSCALL_EXIT; - event_notifier_param.event.u.syscall.abi = LTTNG_KERNEL_ABI_SYSCALL_ABI_COMPAT; - break; - } - strncat(event_notifier_param.event.name, desc->event_name, - LTTNG_KERNEL_ABI_SYM_NAME_LEN - strlen(event_notifier_param.event.name) - 1); - event_notifier_param.event.name[LTTNG_KERNEL_ABI_SYM_NAME_LEN - 1] = '\0'; - event_notifier_param.event.instrumentation = LTTNG_KERNEL_ABI_SYSCALL; - event_notifier_param.event.token = user_token; - event_notifier_param.error_counter_index = error_counter_index; - - event_notifier_enabler = lttng_event_notifier_enabler_create(LTTNG_ENABLER_FORMAT_NAME, - &event_notifier_param, group); - WARN_ON_ONCE(!event_notifier_enabler); - event = _lttng_kernel_event_create(&event_notifier_enabler->parent, desc); - lttng_event_enabler_destroy(&event_notifier_enabler->parent); - if (IS_ERR(event)) { - printk(KERN_INFO "Unable to create event_notifier %s\n", - desc->event_name); - ret = -ENOMEM; - goto end; - } - - event->priv->u.syscall.syscall_id = i; + lttng_syscall_event_enabler_create_event(&syscall_event_notifier_enabler->parent, desc, NULL, type, i); } - -end: - return ret; - } static @@ -1016,53 +984,25 @@ int lttng_syscalls_create_matching_event_notifiers(struct lttng_event_enabler_co event_notifier_enabler = container_of(event_enabler, struct lttng_event_notifier_enabler, parent); if (entryexit == LTTNG_KERNEL_ABI_SYSCALL_ENTRY || entryexit == LTTNG_KERNEL_ABI_SYSCALL_ENTRYEXIT) { - ret = create_matching_event_notifiers(event_notifier_enabler, + create_matching_event_notifiers(event_notifier_enabler, sc_table.table, sc_table.len, SC_TYPE_ENTRY); - if (ret) - goto end; - - ret = create_matching_event_notifiers(event_notifier_enabler, + create_matching_event_notifiers(event_notifier_enabler, compat_sc_table.table, compat_sc_table.len, SC_TYPE_COMPAT_ENTRY); - if (ret) - goto end; - - ret = create_unknown_event_notifier(event_notifier_enabler, - SC_TYPE_ENTRY); - if (ret) - goto end; - - ret = create_unknown_event_notifier(event_notifier_enabler, - SC_TYPE_COMPAT_ENTRY); - if (ret) - goto end; + create_unknown_event_notifier(event_notifier_enabler, SC_TYPE_ENTRY); + create_unknown_event_notifier(event_notifier_enabler, SC_TYPE_COMPAT_ENTRY); } if (entryexit == LTTNG_KERNEL_ABI_SYSCALL_EXIT || entryexit == LTTNG_KERNEL_ABI_SYSCALL_ENTRYEXIT) { - ret = create_matching_event_notifiers(event_notifier_enabler, + create_matching_event_notifiers(event_notifier_enabler, sc_exit_table.table, sc_exit_table.len, SC_TYPE_EXIT); - if (ret) - goto end; - - ret = create_unknown_event_notifier(event_notifier_enabler, - SC_TYPE_EXIT); - if (ret) - goto end; - - ret = create_matching_event_notifiers(event_notifier_enabler, + create_matching_event_notifiers(event_notifier_enabler, compat_sc_exit_table.table, compat_sc_exit_table.len, SC_TYPE_COMPAT_EXIT); - if (ret) - goto end; - - ret = create_unknown_event_notifier(event_notifier_enabler, - SC_TYPE_COMPAT_EXIT); - if (ret) - goto end; + create_unknown_event_notifier(event_notifier_enabler, SC_TYPE_EXIT); + create_unknown_event_notifier(event_notifier_enabler, SC_TYPE_COMPAT_EXIT); } - -end: return ret; } -- 2.34.1