X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=liblttng-ust%2Flttng-ust-statedump.c;h=040223d58409bd93b2ceedb9d8d8979e463beac1;hb=HEAD;hp=eaee338a79d5b740591f015e58bd63c81dd22434;hpb=2208d8b5689264e35ed0a660d8c3c82021cc0367;p=lttng-ust.git diff --git a/liblttng-ust/lttng-ust-statedump.c b/liblttng-ust/lttng-ust-statedump.c deleted file mode 100644 index eaee338a..00000000 --- a/liblttng-ust/lttng-ust-statedump.c +++ /dev/null @@ -1,660 +0,0 @@ -/* - * SPDX-License-Identifier: LGPL-2.1-or-later - * - * Copyright (C) 2013 Paul Woegerer - * Copyright (C) 2015 Antoine Busque - * Copyright (C) 2016 Mathieu Desnoyers - */ - -#define _LGPL_SOURCE -#include -#include -#include -#include -#include -#include -#include -#include - -#include -#include -#include "lttng-tracer-core.h" -#include "lttng-ust-statedump.h" -#include "jhash.h" -#include "getenv.h" -#include "compat.h" -#include "ust-events-internal.h" - -#define TRACEPOINT_DEFINE -#include "ust_lib.h" /* Only define. */ - -#define TRACEPOINT_CREATE_PROBES -#define TP_SESSION_CHECK -#include "lttng-ust-statedump-provider.h" /* Define and create probes. */ - -struct dl_iterate_data { - int exec_found; - bool first; - bool cancel; -}; - -struct bin_info_data { - void *base_addr_ptr; - char resolved_path[PATH_MAX]; - char *dbg_file; - uint8_t *build_id; - uint64_t memsz; - size_t build_id_len; - int vdso; - uint32_t crc; - uint8_t is_pic; - uint8_t has_build_id; - uint8_t has_debug_link; -}; - -struct lttng_ust_dl_node { - struct bin_info_data bin_data; - struct cds_hlist_node node; - bool traced; - bool marked; -}; - -#define UST_DL_STATE_HASH_BITS 8 -#define UST_DL_STATE_TABLE_SIZE (1 << UST_DL_STATE_HASH_BITS) -struct cds_hlist_head dl_state_table[UST_DL_STATE_TABLE_SIZE]; - -typedef void (*tracepoint_cb)(struct lttng_ust_session *session, void *priv); - -static -struct lttng_ust_dl_node *alloc_dl_node(const struct bin_info_data *bin_data) -{ - struct lttng_ust_dl_node *e; - - e = zmalloc(sizeof(struct lttng_ust_dl_node)); - if (!e) - return NULL; - if (bin_data->dbg_file) { - e->bin_data.dbg_file = strdup(bin_data->dbg_file); - if (!e->bin_data.dbg_file) - goto error; - } - if (bin_data->build_id) { - e->bin_data.build_id = zmalloc(bin_data->build_id_len); - if (!e->bin_data.build_id) - goto error; - memcpy(e->bin_data.build_id, bin_data->build_id, - bin_data->build_id_len); - } - e->bin_data.base_addr_ptr = bin_data->base_addr_ptr; - memcpy(e->bin_data.resolved_path, bin_data->resolved_path, PATH_MAX); - e->bin_data.memsz = bin_data->memsz; - e->bin_data.build_id_len = bin_data->build_id_len; - e->bin_data.vdso = bin_data->vdso; - e->bin_data.crc = bin_data->crc; - e->bin_data.is_pic = bin_data->is_pic; - e->bin_data.has_build_id = bin_data->has_build_id; - e->bin_data.has_debug_link = bin_data->has_debug_link; - return e; - -error: - free(e->bin_data.build_id); - free(e->bin_data.dbg_file); - free(e); - return NULL; -} - -static -void free_dl_node(struct lttng_ust_dl_node *e) -{ - free(e->bin_data.build_id); - free(e->bin_data.dbg_file); - free(e); -} - -/* Return 0 if same, nonzero if not. */ -static -int compare_bin_data(const struct bin_info_data *a, - const struct bin_info_data *b) -{ - if (a->base_addr_ptr != b->base_addr_ptr) - return -1; - if (strcmp(a->resolved_path, b->resolved_path) != 0) - return -1; - if (a->dbg_file && !b->dbg_file) - return -1; - if (!a->dbg_file && b->dbg_file) - return -1; - if (a->dbg_file && strcmp(a->dbg_file, b->dbg_file) != 0) - return -1; - if (a->build_id && !b->build_id) - return -1; - if (!a->build_id && b->build_id) - return -1; - if (a->build_id_len != b->build_id_len) - return -1; - if (a->build_id && - memcmp(a->build_id, b->build_id, a->build_id_len) != 0) - return -1; - if (a->memsz != b->memsz) - return -1; - if (a->vdso != b->vdso) - return -1; - if (a->crc != b->crc) - return -1; - if (a->is_pic != b->is_pic) - return -1; - if (a->has_build_id != b->has_build_id) - return -1; - if (a->has_debug_link != b->has_debug_link) - return -1; - return 0; -} - -static -struct lttng_ust_dl_node *find_or_create_dl_node(struct bin_info_data *bin_data) -{ - struct cds_hlist_head *head; - struct lttng_ust_dl_node *e; - unsigned int hash; - bool found = false; - - hash = jhash(&bin_data->base_addr_ptr, - sizeof(bin_data->base_addr_ptr), 0); - head = &dl_state_table[hash & (UST_DL_STATE_TABLE_SIZE - 1)]; - cds_hlist_for_each_entry_2(e, head, node) { - if (compare_bin_data(&e->bin_data, bin_data) != 0) - continue; - found = true; - break; - } - if (!found) { - /* Create */ - e = alloc_dl_node(bin_data); - if (!e) - return NULL; - cds_hlist_add_head(&e->node, head); - } - return e; -} - -static -void remove_dl_node(struct lttng_ust_dl_node *e) -{ - cds_hlist_del(&e->node); -} - -/* - * Trace statedump event into all sessions owned by the caller thread - * for which statedump is pending. - */ -static -void trace_statedump_event(tracepoint_cb tp_cb, void *owner, void *priv) -{ - struct cds_list_head *sessionsp; - struct lttng_ust_session_private *session_priv; - - sessionsp = lttng_get_sessions(); - cds_list_for_each_entry(session_priv, sessionsp, node) { - if (session_priv->owner != owner) - continue; - if (!session_priv->statedump_pending) - continue; - tp_cb(session_priv->pub, priv); - } -} - -static -void trace_bin_info_cb(struct lttng_ust_session *session, void *priv) -{ - struct bin_info_data *bin_data = (struct bin_info_data *) priv; - - tracepoint(lttng_ust_statedump, bin_info, - session, bin_data->base_addr_ptr, - bin_data->resolved_path, bin_data->memsz, - bin_data->is_pic, bin_data->has_build_id, - bin_data->has_debug_link); -} - -static -void trace_build_id_cb(struct lttng_ust_session *session, void *priv) -{ - struct bin_info_data *bin_data = (struct bin_info_data *) priv; - - tracepoint(lttng_ust_statedump, build_id, - session, bin_data->base_addr_ptr, - bin_data->build_id, bin_data->build_id_len); -} - -static -void trace_debug_link_cb(struct lttng_ust_session *session, void *priv) -{ - struct bin_info_data *bin_data = (struct bin_info_data *) priv; - - tracepoint(lttng_ust_statedump, debug_link, - session, bin_data->base_addr_ptr, - bin_data->dbg_file, bin_data->crc); -} - -static -void procname_cb(struct lttng_ust_session *session, void *priv) -{ - char *procname = (char *) priv; - tracepoint(lttng_ust_statedump, procname, session, procname); -} - -static -void trace_start_cb(struct lttng_ust_session *session, void *priv __attribute__((unused))) -{ - tracepoint(lttng_ust_statedump, start, session); -} - -static -void trace_end_cb(struct lttng_ust_session *session, void *priv __attribute__((unused))) -{ - tracepoint(lttng_ust_statedump, end, session); -} - -static -int get_elf_info(struct bin_info_data *bin_data) -{ - struct lttng_ust_elf *elf; - int ret = 0, found; - - elf = lttng_ust_elf_create(bin_data->resolved_path); - if (!elf) { - ret = -1; - goto end; - } - - ret = lttng_ust_elf_get_memsz(elf, &bin_data->memsz); - if (ret) { - goto end; - } - - found = 0; - ret = lttng_ust_elf_get_build_id(elf, &bin_data->build_id, - &bin_data->build_id_len, - &found); - if (ret) { - goto end; - } - bin_data->has_build_id = !!found; - found = 0; - ret = lttng_ust_elf_get_debug_link(elf, &bin_data->dbg_file, - &bin_data->crc, - &found); - if (ret) { - goto end; - } - bin_data->has_debug_link = !!found; - - bin_data->is_pic = lttng_ust_elf_is_pic(elf); - -end: - lttng_ust_elf_destroy(elf); - return ret; -} - -static -void trace_baddr(struct bin_info_data *bin_data, void *owner) -{ - trace_statedump_event(trace_bin_info_cb, owner, bin_data); - - if (bin_data->has_build_id) - trace_statedump_event(trace_build_id_cb, owner, bin_data); - - if (bin_data->has_debug_link) - trace_statedump_event(trace_debug_link_cb, owner, bin_data); -} - -static -int extract_baddr(struct bin_info_data *bin_data) -{ - int ret = 0; - struct lttng_ust_dl_node *e; - - if (!bin_data->vdso) { - ret = get_elf_info(bin_data); - if (ret) { - goto end; - } - } else { - bin_data->memsz = 0; - bin_data->has_build_id = 0; - bin_data->has_debug_link = 0; - } - - e = find_or_create_dl_node(bin_data); - if (!e) { - ret = -1; - goto end; - } - e->marked = true; -end: - free(bin_data->build_id); - bin_data->build_id = NULL; - free(bin_data->dbg_file); - bin_data->dbg_file = NULL; - return ret; -} - -static -void trace_statedump_start(void *owner) -{ - trace_statedump_event(trace_start_cb, owner, NULL); -} - -static -void trace_statedump_end(void *owner) -{ - trace_statedump_event(trace_end_cb, owner, NULL); -} - -static -void iter_begin(struct dl_iterate_data *data) -{ - unsigned int i; - - /* - * UST lock nests within dynamic loader lock. - * - * Hold this lock across handling of the module listing to - * protect memory allocation at early process start, due to - * interactions with libc-wrapper lttng malloc instrumentation. - */ - if (ust_lock()) { - data->cancel = true; - return; - } - - /* Ensure all entries are unmarked. */ - for (i = 0; i < UST_DL_STATE_TABLE_SIZE; i++) { - struct cds_hlist_head *head; - struct lttng_ust_dl_node *e; - - head = &dl_state_table[i]; - cds_hlist_for_each_entry_2(e, head, node) - assert(!e->marked); - } -} - -static -void trace_lib_load(const struct bin_info_data *bin_data, void *ip) -{ - tracepoint(lttng_ust_lib, load, - ip, bin_data->base_addr_ptr, bin_data->resolved_path, - bin_data->memsz, bin_data->has_build_id, - bin_data->has_debug_link); - - if (bin_data->has_build_id) { - tracepoint(lttng_ust_lib, build_id, - ip, bin_data->base_addr_ptr, bin_data->build_id, - bin_data->build_id_len); - } - - if (bin_data->has_debug_link) { - tracepoint(lttng_ust_lib, debug_link, - ip, bin_data->base_addr_ptr, bin_data->dbg_file, - bin_data->crc); - } -} - -static -void trace_lib_unload(const struct bin_info_data *bin_data, void *ip) -{ - tracepoint(lttng_ust_lib, unload, ip, bin_data->base_addr_ptr); -} - -static -void iter_end(struct dl_iterate_data *data, void *ip) -{ - unsigned int i; - - if (data->cancel) - goto end; - /* - * Iterate on hash table. - * For each marked, traced, do nothing. - * For each marked, not traced, trace lib open event. traced = true. - * For each unmarked, traced, trace lib close event. remove node. - * For each unmarked, not traced, remove node. - */ - for (i = 0; i < UST_DL_STATE_TABLE_SIZE; i++) { - struct cds_hlist_head *head; - struct lttng_ust_dl_node *e; - - head = &dl_state_table[i]; - cds_hlist_for_each_entry_2(e, head, node) { - if (e->marked) { - if (!e->traced) { - trace_lib_load(&e->bin_data, ip); - e->traced = true; - } - e->marked = false; - } else { - if (e->traced) - trace_lib_unload(&e->bin_data, ip); - remove_dl_node(e); - free_dl_node(e); - } - } - } -end: - ust_unlock(); -} - -static -int extract_bin_info_events(struct dl_phdr_info *info, size_t size __attribute__((unused)), void *_data) -{ - int j, ret = 0; - struct dl_iterate_data *data = _data; - - if (data->first) { - iter_begin(data); - data->first = false; - } - - if (data->cancel) - goto end; - - for (j = 0; j < info->dlpi_phnum; j++) { - struct bin_info_data bin_data; - - if (info->dlpi_phdr[j].p_type != PT_LOAD) - continue; - - memset(&bin_data, 0, sizeof(bin_data)); - - /* Calculate virtual memory address of the loadable segment */ - bin_data.base_addr_ptr = (void *) info->dlpi_addr + - info->dlpi_phdr[j].p_vaddr; - - if ((info->dlpi_name == NULL || info->dlpi_name[0] == 0)) { - /* - * Only the first phdr without a dlpi_name - * encountered is considered as the program - * executable. The rest are vdsos. - */ - if (!data->exec_found) { - ssize_t path_len; - data->exec_found = 1; - - /* - * Use /proc/self/exe to resolve the - * executable's full path. - */ - path_len = readlink("/proc/self/exe", - bin_data.resolved_path, - PATH_MAX - 1); - if (path_len <= 0) - break; - - bin_data.resolved_path[path_len] = '\0'; - bin_data.vdso = 0; - } else { - snprintf(bin_data.resolved_path, - PATH_MAX - 1, "[vdso]"); - bin_data.vdso = 1; - } - } else { - /* - * For regular dl_phdr_info entries check if - * the path to the binary really exists. If not, - * treat as vdso and use dlpi_name as 'path'. - */ - if (!realpath(info->dlpi_name, - bin_data.resolved_path)) { - snprintf(bin_data.resolved_path, - PATH_MAX - 1, "[%s]", - info->dlpi_name); - bin_data.vdso = 1; - } else { - bin_data.vdso = 0; - } - } - - ret = extract_baddr(&bin_data); - break; - } -end: - return ret; -} - -static -void ust_dl_table_statedump(void *owner) -{ - unsigned int i; - - if (ust_lock()) - goto end; - - /* Statedump each traced table entry into session for owner. */ - for (i = 0; i < UST_DL_STATE_TABLE_SIZE; i++) { - struct cds_hlist_head *head; - struct lttng_ust_dl_node *e; - - head = &dl_state_table[i]; - cds_hlist_for_each_entry_2(e, head, node) { - if (e->traced) - trace_baddr(&e->bin_data, owner); - } - } - -end: - ust_unlock(); -} - -void lttng_ust_dl_update(void *ip) -{ - struct dl_iterate_data data; - - if (lttng_ust_getenv("LTTNG_UST_WITHOUT_BADDR_STATEDUMP")) - return; - - /* - * Fixup lttng-ust TLS when called from dlopen/dlclose - * instrumentation. - */ - lttng_ust_fixup_tls(); - - data.exec_found = 0; - data.first = true; - data.cancel = false; - /* - * Iterate through the list of currently loaded shared objects and - * generate tables entries for loadable segments using - * extract_bin_info_events. - * Removed libraries are detected by mark-and-sweep: marking is - * done in the iteration over libraries, and sweeping is - * performed by iter_end(). - */ - dl_iterate_phdr(extract_bin_info_events, &data); - if (data.first) - iter_begin(&data); - iter_end(&data, ip); -} - -/* - * Generate a statedump of base addresses of all shared objects loaded - * by the traced application, as well as for the application's - * executable itself. - */ -static -int do_baddr_statedump(void *owner) -{ - if (lttng_ust_getenv("LTTNG_UST_WITHOUT_BADDR_STATEDUMP")) - return 0; - lttng_ust_dl_update(LTTNG_UST_CALLER_IP()); - ust_dl_table_statedump(owner); - return 0; -} - -static -int do_procname_statedump(void *owner) -{ - if (lttng_ust_getenv("LTTNG_UST_WITHOUT_PROCNAME_STATEDUMP")) - return 0; - - trace_statedump_event(procname_cb, owner, lttng_ust_sockinfo_get_procname(owner)); - return 0; -} - -/* - * Generate a statedump of a given traced application. A statedump is - * delimited by start and end events. For a given (process, session) - * pair, begin/end events are serialized and will match. However, in a - * session, statedumps from different processes may be - * interleaved. The vpid context should be used to identify which - * events belong to which process. - * - * Grab the ust_lock outside of the RCU read-side lock because we - * perform synchronize_rcu with the ust_lock held, which can trigger - * deadlocks otherwise. - */ -int do_lttng_ust_statedump(void *owner) -{ - ust_lock_nocheck(); - trace_statedump_start(owner); - ust_unlock(); - - do_procname_statedump(owner); - do_baddr_statedump(owner); - - ust_lock_nocheck(); - trace_statedump_end(owner); - ust_unlock(); - - return 0; -} - -void lttng_ust_statedump_init(void) -{ - __tracepoints__init(); - __tracepoints__ptrs_init(); - __lttng_events_init__lttng_ust_statedump(); - lttng_ust_dl_update(LTTNG_UST_CALLER_IP()); -} - -static -void ust_dl_state_destroy(void) -{ - unsigned int i; - - for (i = 0; i < UST_DL_STATE_TABLE_SIZE; i++) { - struct cds_hlist_head *head; - struct lttng_ust_dl_node *e, *tmp; - - head = &dl_state_table[i]; - cds_hlist_for_each_entry_safe_2(e, tmp, head, node) - free_dl_node(e); - CDS_INIT_HLIST_HEAD(head); - } -} - -void lttng_ust_statedump_destroy(void) -{ - __lttng_events_exit__lttng_ust_statedump(); - __tracepoints__ptrs_destroy(); - __tracepoints__destroy(); - ust_dl_state_destroy(); -}