From 95c25348271ce9978f1b3e892685110ad52d13ea Mon Sep 17 00:00:00 2001 From: Paul Woegerer Date: Thu, 14 Nov 2013 19:39:49 +0100 Subject: [PATCH] Implement base-address-state tracing Dump the base-address state (executable and shared objects) into session on session-enable (per-session events). Signed-off-by: Paul Woegerer Signed-off-by: Mathieu Desnoyers --- include/lttng/ust-tracepoint-event.h | 14 +++++ liblttng-ust-baddr/Makefile.am | 4 +- liblttng-ust-baddr/lttng-ust-baddr.c | 72 ++++++++++++++++++++++++ liblttng-ust-baddr/ust_baddr_statedump.c | 21 +++++++ liblttng-ust-baddr/ust_baddr_statedump.h | 60 ++++++++++++++++++++ liblttng-ust/lttng-events.c | 2 + liblttng-ust/lttng-tracer-core.h | 3 + liblttng-ust/lttng-ust-comm.c | 60 ++++++++++++++++++++ 8 files changed, 235 insertions(+), 1 deletion(-) create mode 100644 liblttng-ust-baddr/ust_baddr_statedump.c create mode 100644 liblttng-ust-baddr/ust_baddr_statedump.h diff --git a/include/lttng/ust-tracepoint-event.h b/include/lttng/ust-tracepoint-event.h index bb3a05d5..be580307 100644 --- a/include/lttng/ust-tracepoint-event.h +++ b/include/lttng/ust-tracepoint-event.h @@ -479,6 +479,18 @@ size_t __event_get_align__##_provider##___##_name(_TP_ARGS_PROTO(_args)) \ #undef TP_FIELDS #define TP_FIELDS(...) __VA_ARGS__ +/* + * For state dump, check that "session" argument (mandatory) matches the + * session this event belongs to. Ensures that we write state dump data only + * into the started session, not into all sessions. + */ +#undef _TP_SESSION_CHECK +#ifdef TP_SESSION_CHECK +#define _TP_SESSION_CHECK(session, csession) (session == csession) +#else /* TP_SESSION_CHECK */ +#define _TP_SESSION_CHECK(session, csession) 1 +#endif /* TP_SESSION_CHECK */ + /* * Using twice size for filter stack data to hold size and pointer for * each field (worse case). For integers, max size required is 64-bit. @@ -506,6 +518,8 @@ void __event_probe__##_provider##___##_name(_TP_ARGS_DATA_PROTO(_args)) \ \ if (0) \ (void) __dynamic_len_idx; /* don't warn if unused */ \ + if (!_TP_SESSION_CHECK(session, __chan->session)) \ + return; \ if (caa_unlikely(!CMM_ACCESS_ONCE(__chan->session->active))) \ return; \ if (caa_unlikely(!CMM_ACCESS_ONCE(__chan->enabled))) \ diff --git a/liblttng-ust-baddr/Makefile.am b/liblttng-ust-baddr/Makefile.am index afa9489f..0d3cf289 100644 --- a/liblttng-ust-baddr/Makefile.am +++ b/liblttng-ust-baddr/Makefile.am @@ -5,7 +5,9 @@ lib_LTLIBRARIES = liblttng-ust-baddr.la liblttng_ust_baddr_la_SOURCES = \ lttng-ust-baddr.c \ ust_baddr.c \ - ust_baddr.h + ust_baddr.h \ + ust_baddr_statedump.c \ + ust_baddr_statedump.h liblttng_ust_baddr_la_LIBADD = \ -L$(top_builddir)/liblttng-ust/.libs \ -llttng-ust diff --git a/liblttng-ust-baddr/lttng-ust-baddr.c b/liblttng-ust-baddr/lttng-ust-baddr.c index f24a1717..a8569656 100644 --- a/liblttng-ust-baddr/lttng-ust-baddr.c +++ b/liblttng-ust-baddr/lttng-ust-baddr.c @@ -34,6 +34,7 @@ #define TRACEPOINT_DEFINE #include "ust_baddr.h" +#include "ust_baddr_statedump.h" int lttng_ust_push_baddr(void *so_base, const char *so_name) @@ -62,3 +63,74 @@ lttng_ust_pop_baddr(void *so_base) tracepoint(ust_baddr, pop, so_base); return 0; } + +static int +extract_soinfo_events(struct dl_phdr_info *info, size_t size, void *data) +{ + int j; + int num_loadable_segment = 0; + + for (j = 0; j < info->dlpi_phnum; j++) { + char resolved_path[PATH_MAX]; + struct stat sostat; + void *base_addr_ptr; + + if (info->dlpi_phdr[j].p_type != PT_LOAD) + continue; + + /* Calculate virtual memory address of the loadable segment */ + base_addr_ptr = (void *) info->dlpi_addr + + info->dlpi_phdr[j].p_vaddr; + + num_loadable_segment += 1; + if ((info->dlpi_name == NULL || info->dlpi_name[0] == 0) + && num_loadable_segment == 1) { + /* + * If the iterated element is the executable itself we + * have to use Dl_info to determine its full path + */ + Dl_info dl_info = { 0 }; + if (!dladdr(base_addr_ptr, &dl_info)) + return 0; + if (!realpath(dl_info.dli_fname, resolved_path)) + return 0; + } else { + /* + * For regular dl_phdr_info entries we have to check if + * the path to the shared object really exists + */ + if (!realpath(info->dlpi_name, resolved_path)) { + /* Found vDSO, put the 'path' into brackets */ + snprintf(resolved_path, PATH_MAX - 1, "[%s]", + info->dlpi_name); + } + } + + if (stat(resolved_path, &sostat)) { + sostat.st_size = 0; + sostat.st_mtime = -1; + } + + tracepoint(ust_baddr_statedump, soinfo, + (struct lttng_session *) data, base_addr_ptr, + resolved_path, sostat.st_size, sostat.st_mtime); + + /* + * We are only interested in the base address (lowest virtual + * address associated with the memory image), skip the rest + */ + break; + } + return 0; +} + +int +lttng_ust_baddr_statedump(struct lttng_session *session) +{ + /* + * Iterate through the list of currently loaded shared objects and + * generate events for loadable segments using extract_soinfo_events + */ + dl_iterate_phdr(extract_soinfo_events, session); + return 0; +} diff --git a/liblttng-ust-baddr/ust_baddr_statedump.c b/liblttng-ust-baddr/ust_baddr_statedump.c new file mode 100644 index 00000000..75f74ca7 --- /dev/null +++ b/liblttng-ust-baddr/ust_baddr_statedump.c @@ -0,0 +1,21 @@ +/* + * Copyright (C) 2013 Paul Woegerer + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#define TRACEPOINT_CREATE_PROBES +#define TP_SESSION_CHECK +#include "ust_baddr_statedump.h" diff --git a/liblttng-ust-baddr/ust_baddr_statedump.h b/liblttng-ust-baddr/ust_baddr_statedump.h new file mode 100644 index 00000000..77a9af48 --- /dev/null +++ b/liblttng-ust-baddr/ust_baddr_statedump.h @@ -0,0 +1,60 @@ +#undef TRACEPOINT_PROVIDER +#define TRACEPOINT_PROVIDER ust_baddr_statedump + +#if !defined(_TRACEPOINT_UST_BADDR_STATEDUMP_H) || defined(TRACEPOINT_HEADER_MULTI_READ) +#define _TRACEPOINT_UST_BADDR_STATEDUMP_H + +#ifdef __cplusplus +extern "C" { +#endif + +/* + * Copyright (C) 2013 Paul Woegerer + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#include +#include +#include + +#define LTTNG_UST_BADDR_STATEDUMP_PROVIDER +#include + +TRACEPOINT_EVENT(ust_baddr_statedump, soinfo, + TP_ARGS(struct lttng_session *, session, void *, baddr, const char*, sopath, int64_t, size, int64_t, mtime), + TP_FIELDS( + ctf_integer_hex(void *, baddr, baddr) + ctf_string(sopath, sopath) + ctf_integer(int64_t, size, size) + ctf_integer(int64_t, mtime, mtime) + ) +) + +#endif /* _TRACEPOINT_UST_BADDR_STATEDUMP_H */ + +#undef TRACEPOINT_INCLUDE +#define TRACEPOINT_INCLUDE "./ust_baddr_statedump.h" + +/* This part must be outside ifdef protection */ +#include + +#ifdef __cplusplus +} +#endif diff --git a/liblttng-ust/lttng-events.c b/liblttng-ust/lttng-events.c index 61021f3a..77515843 100644 --- a/liblttng-ust/lttng-events.c +++ b/liblttng-ust/lttng-events.c @@ -293,6 +293,8 @@ int lttng_session_enable(struct lttng_session *session) /* Set atomically the state to "active" */ CMM_ACCESS_ONCE(session->active) = 1; CMM_ACCESS_ONCE(session->been_active) = 1; + + lttng_ust_sockinfo_session_enabled(session->owner, session); end: return ret; } diff --git a/liblttng-ust/lttng-tracer-core.h b/liblttng-ust/lttng-tracer-core.h index f643a7e5..e7f549e0 100644 --- a/liblttng-ust/lttng-tracer-core.h +++ b/liblttng-ust/lttng-tracer-core.h @@ -45,4 +45,7 @@ const char *lttng_ust_obj_get_name(int id); int lttng_get_notify_socket(void *owner); +void lttng_ust_sockinfo_session_enabled(void *owner, + struct lttng_session *session_enabled); + #endif /* _LTTNG_TRACER_CORE_H */ diff --git a/liblttng-ust/lttng-ust-comm.c b/liblttng-ust/lttng-ust-comm.c index 597712bc..77d8e3fc 100644 --- a/liblttng-ust/lttng-ust-comm.c +++ b/liblttng-ust/lttng-ust-comm.c @@ -34,6 +34,7 @@ #include #include #include +#include #include #include #include @@ -106,6 +107,7 @@ struct sock_info { char wait_shm_path[PATH_MAX]; char *wait_shm_mmap; + struct lttng_session *session_enabled; }; /* Socket from app (connect) to session daemon (listen) for communication */ @@ -122,6 +124,8 @@ struct sock_info global_apps = { .notify_socket = -1, .wait_shm_path = "/" LTTNG_UST_WAIT_FILENAME, + + .session_enabled = NULL, }; /* TODO: allow global_apps_sock_path override */ @@ -135,6 +139,8 @@ struct sock_info local_apps = { .socket = -1, .notify_socket = -1, + + .session_enabled = NULL, }; static int wait_poll_fallback; @@ -177,6 +183,7 @@ static const char *cmd_name_mapping[] = { static const char *str_timeout; static int got_timeout_env; +static void *ust_baddr_handle; extern void lttng_ring_buffer_client_overwrite_init(void); extern void lttng_ring_buffer_client_overwrite_rt_init(void); @@ -235,6 +242,39 @@ void print_cmd(int cmd, int handle) lttng_ust_obj_get_name(handle), handle); } +static +void *lttng_ust_baddr_handle(void) +{ + if (!ust_baddr_handle) { + ust_baddr_handle = dlopen( + "liblttng-ust-baddr.so.0", RTLD_NOW | RTLD_GLOBAL); + if (ust_baddr_handle == NULL) + ERR("%s", dlerror()); + } + return ust_baddr_handle; +} + +static +int lttng_ust_baddr_statedump(struct lttng_session *session) +{ + static + int (*lttng_ust_baddr_init_fn)(struct lttng_session *); + + if (!lttng_ust_baddr_init_fn) { + void *baddr_handle = lttng_ust_baddr_handle(); + if (baddr_handle) { + lttng_ust_baddr_init_fn = dlsym(baddr_handle, + "lttng_ust_baddr_statedump"); + if (lttng_ust_baddr_init_fn == NULL) + ERR("%s", dlerror()); + } + if (!lttng_ust_baddr_init_fn) + return -1; + } + + return lttng_ust_baddr_init_fn(session); +} + static int setup_local_apps(void) { @@ -1206,6 +1246,13 @@ restart: ret = handle_message(sock_info, sock, &lum); if (ret) { ERR("Error handling message for %s socket", sock_info->name); + } else { + struct lttng_session *session = + sock_info->session_enabled; + if (session) { + sock_info->session_enabled = NULL; + lttng_ust_baddr_statedump(session); + } } continue; default: @@ -1442,6 +1489,12 @@ void __attribute__((destructor)) lttng_ust_exit(void) * cleanup the threads if there are stalled in a syscall. */ lttng_ust_cleanup(1); + + if (ust_baddr_handle) { + int ret = dlclose(ust_baddr_handle); + if (ret) + ERR("%s", dlerror()); + } } /* @@ -1519,3 +1572,10 @@ void ust_after_fork_child(sigset_t *restore_sigset) ust_after_fork_common(restore_sigset); lttng_ust_init(); } + +void lttng_ust_sockinfo_session_enabled(void *owner, + struct lttng_session *session_enabled) +{ + struct sock_info *sock_info = owner; + sock_info->session_enabled = session_enabled; +} -- 2.34.1