On 11/20/2013 02:26 PM, Amit Margalit wrote: > Yes, that would be of value to me.
OK, I will submit a patch for that. > > Can you also have a variable to avoid tracking dlopen()/dlclose() ? > Maybe one variable to disable both? For tracking dlopen()/dlclose() you need to explicitly LD_PRELOAD (liblttng-ust-dl.so.0) anyway. So no need for an extra variable there. -- Best, Paul > > Thanks, > > Amit Margalit > IBM XIV - /Storage Reinvented/ > XIV-NAS Development Team > Tel. 03-689-7774 > Fax. 03-689-7230 > > > > From: "Woegerer, Paul" <[email protected]> > To: Amit Margalit/Israel/IBM@IBMIL, Mathieu Desnoyers > <[email protected]> > Cc: <[email protected]> > Date: 11/19/2013 04:41 PM > Subject: Re: [lttng-dev] [PATCH v3 2/2] Implement > base-address-state tracing > ------------------------------------------------------------------------ > > > > On 11/18/2013 08:59 AM, Amit Margalit wrote: > > Hi, > > > > I understand, and I see two issue with this - > > > > 1. The application will still perform all the tracking, but when the > > event is to be generated, it will be checked and since it is > > disabled, will not be emitted. > > While the overhead of checking whether the event is enabled is > > indeed minimal, the overhead of tracking existing state, is not > > negligible - it includes code, data and CPU cycles. > > 2. I believe that the average user will simply want to use > > "enable-event -u -a" or similar, and should not care about later > > disabling these specific events. > > > > > > I believe this ought to be a compile-time option, and I don't mind if > > it defaults to "Enabled"... > > How about an environment variable (e.g. > LTTNG_UST_WITHOUT_BADDR_STATEDUMP) that suppresses base address state > tracing. > > Would that be of value to you ? > > -- > Best, > Paul > > > > > What do you think? > > > > Amit Margalit > > IBM XIV - /Storage Reinvented/ > > XIV-NAS Development Team > > Tel. 03-689-7774 > > Fax. 03-689-7230 > > > > > > > > From: Mathieu Desnoyers <[email protected]> > > To: Amit Margalit/Israel/IBM@IBMIL > > Cc: [email protected], Paul Woegerer > > <[email protected]> > > Date: 11/17/2013 04:02 PM > > Subject: Re: [lttng-dev] [PATCH v3 2/2] Implement > > base-address-state tracing > > ------------------------------------------------------------------------ > > > > > > > > ------------------------------------------------------------------------ > > > > *From: *"Amit Margalit" <[email protected]>* > > To: *"Mathieu Desnoyers" <[email protected]>* > > Cc: *[email protected], "Paul Woegerer" > > <[email protected]>* > > Sent: *Sunday, November 17, 2013 4:36:19 AM* > > Subject: *Re: [lttng-dev] [PATCH v3 2/2] Implement base-address-state > > tracing > > > > I guess I missed something in the discussion - is this going to be > > active all the time, or can I disable it somehow? > > > > Maybe a command-line switch to turn this off? > > > > For me this is overhead that I don't need and don't want. > > > > You just have to not enable those new events if you don't care about > > them. > > > > Thanks, > > > > Mathieu > > > > > > Thanks, > > > > Amit Margalit > > IBM XIV - /Storage Reinvented/ > > XIV-NAS Development Team > > Tel. 03-689-7774 > > Fax. 03-689-7230 > > > > > > > > From: Mathieu Desnoyers <[email protected]> > > To: Paul Woegerer <[email protected]> > > Cc: [email protected] > > Date: 11/14/2013 09:30 PM > > Subject: Re: [lttng-dev] [PATCH v3 2/2] Implement > > base-address-state tracing > > ------------------------------------------------------------------------ > > > > > > > > ----- Original Message ----- > > > From: "Paul Woegerer" <[email protected]> > > > To: [email protected], "mathieu desnoyers" > > <[email protected]> > > > Sent: Thursday, November 14, 2013 1:39:49 PM > > > Subject: [PATCH v3 2/2] Implement base-address-state tracing > > > > > > Dump the base-address state (executable and shared objects) into > session > > > on session-enable (per-session events). > > > > Merged, thanks ! > > > > Mathieu > > > > > > > > Signed-off-by: Paul Woegerer <[email protected]> > > > --- > > > 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 bb3a05d..be58030 100644 > > > --- a/include/lttng/ust-tracepoint-event.h > > > +++ b/include/lttng/ust-tracepoint-event.h > > > @@ -480,6 +480,18 @@ size_t > > > __event_get_align__##_provider##___##_name(_TP_ARGS_PROTO(_args)) > \ > > > #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. > > > * Same for double-precision floats. Those fit within > > > @@ -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 afa9489..0d3cf28 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 f24a171..a856965 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 0000000..75f74ca > > > --- /dev/null > > > +++ b/liblttng-ust-baddr/ust_baddr_statedump.c > > > @@ -0,0 +1,21 @@ > > > +/* > > > + * Copyright (C) 2013 Paul Woegerer <[email protected]> > > > + * > > > + * 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 0000000..77a9af4 > > > --- /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 <[email protected]> > > > + * > > > + * 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 <stdint.h> > > > +#include <unistd.h> > > > +#include <lttng/ust-events.h> > > > + > > > +#define LTTNG_UST_BADDR_STATEDUMP_PROVIDER > > > +#include <lttng/tracepoint.h> > > > + > > > +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 <lttng/tracepoint-event.h> > > > + > > > +#ifdef __cplusplus > > > +} > > > +#endif > > > diff --git a/liblttng-ust/lttng-events.c b/liblttng-ust/lttng-events.c > > > index 26601a6..21e3639 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 f643a7e..e7f549e 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 a6e4ba3..6ef3006 100644 > > > --- a/liblttng-ust/lttng-ust-comm.c > > > +++ b/liblttng-ust/lttng-ust-comm.c > > > @@ -34,6 +34,7 @@ > > > #include <time.h> > > > #include <assert.h> > > > #include <signal.h> > > > +#include <dlfcn.h> > > > #include <urcu/uatomic.h> > > > #include <urcu/futex.h> > > > #include <urcu/compiler.h> > > > @@ -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; > > > @@ -176,6 +182,7 @@ 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) > > > } > > > > > > 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) > > > { > > > const char *home_dir; > > > @@ -1143,6 +1183,13 @@ 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: > > > @@ -1379,6 +1426,12 @@ 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()); > > > + } > > > } > > > > > > /* > > > @@ -1456,3 +1509,10 @@ 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; > > > +} > > > -- > > > 1.8.4.2 > > > > > > > > > > -- > > Mathieu Desnoyers > > EfficiOS Inc._ > > __http://www.efficios.com_ <http://www.efficios.com/> > > > > _______________________________________________ > > lttng-dev mailing list > > [email protected]_ > > __http://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev_ > > > > > > > > > > > > -- > > Mathieu Desnoyers > > EfficiOS Inc. > > http://www.efficios.com > <http://www.efficios.com/><http://www.efficios.com/> > > > -- > Paul Woegerer, SW Development Engineer > Sourcery Analyzer <http://go.mentor.com/sourceryanalyzer> > Mentor Graphics, Embedded Software Division > > -- Paul Woegerer, SW Development Engineer Sourcery Analyzer <http://go.mentor.com/sourceryanalyzer> Mentor Graphics, Embedded Software Division _______________________________________________ lttng-dev mailing list [email protected] http://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev
