From 5e96a46756a5dcd6e348afd84078b9e26438245d Mon Sep 17 00:00:00 2001 From: Mathieu Desnoyers Date: Tue, 9 Aug 2011 09:46:51 -0400 Subject: [PATCH] Add UST_DEBUG env. var. support Signed-off-by: Mathieu Desnoyers --- README | 13 ++++ include/usterr.h | 76 ++++++++++++++++++------ include/usterr_signal_safe.h | 111 +++++++++++++++++++++++++---------- libust/Makefile.am | 3 +- libust/buffers.c | 1 + libust/lttng-ust-abi.c | 1 + libust/tracepoint.c | 1 + libust/ust-core.c | 37 ++++++++++++ 8 files changed, 192 insertions(+), 51 deletions(-) create mode 100644 libust/ust-core.c diff --git a/README b/README index a2d115b1..3d7e18e3 100644 --- a/README +++ b/README @@ -38,6 +38,19 @@ INSTALLATION INSTRUCTIONS: the configure script, to generate it. +USAGE: + + - Create an instrumentation header following the tracepoint examples. + (see tracepoint.h and tests/hello/tp.h). + - Link application with -lust. + - (TODO: start tracing with the "lttng" command from lttng-tools) + + Note: libust debug can be activated by either of the following means: + - Setting the environment variable "UST_DEBUG" when launching the + application. + - Compiling libust with -DUST_DEBUG. + + TRACE VIEWER: LTTV is used for viewing UST traces. LTTV may be obtained at diff --git a/include/usterr.h b/include/usterr.h index dc51d840..cab65407 100644 --- a/include/usterr.h +++ b/include/usterr.h @@ -1,9 +1,14 @@ -/* Copyright (C) 2009 Pierre-Marc Fournier +#ifndef _USTERR_H +#define _USTERR_H + +/* + * Copyright (C) 2009 Pierre-Marc Fournier + * Copyright (C) 2011 Mathieu Desnoyers * * 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. + * License as published by the Free Software Foundation; version 2.1 of + * the License. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of @@ -15,9 +20,6 @@ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ -#ifndef _USTERR_H -#define _USTERR_H - #include #include #include @@ -29,6 +31,20 @@ #include "share.h" +enum ust_loglevel { + UST_LOGLEVEL_UNKNOWN = 0, + UST_LOGLEVEL_NORMAL, + UST_LOGLEVEL_DEBUG, +}; + +extern volatile enum ust_loglevel ust_loglevel; +void init_usterr(void); + +static inline int ust_debug(void) +{ + return ust_loglevel == UST_LOGLEVEL_DEBUG; +} + #ifndef UST_COMPONENT #define UST_COMPONENT libust #endif @@ -37,23 +53,37 @@ #define XSTR(d) STR(d) #define STR(s) #s -/* A dummy function to force format checking */ -static inline void __attribute__ ((format (printf, 1, 2))) - __check_ust_safe_fmt(const char *fmt, ...) -{ -} - #define UST_STR_COMPONENT XSTR(UST_COMPONENT) -#define ERRMSG(fmt, args...) do { fprintf(stderr, UST_STR_COMPONENT "[%ld/%ld]: " fmt " (in %s() at " __FILE__ ":" XSTR(__LINE__) ")\n", (long) getpid(), (long) syscall(SYS_gettid), ## args, __func__); } while(0) +#define ERRMSG(fmt, args...) \ + do { \ + fprintf(stderr, UST_STR_COMPONENT "[%ld/%ld]: " fmt " (in %s() at " __FILE__ ":" XSTR(__LINE__) ")\n", \ + (long) getpid(), \ + (long) syscall(SYS_gettid), \ + ## args, \ + __func__); \ + } while(0) #ifdef UST_DEBUG -# define DBG(fmt, args...) ERRMSG(fmt, ## args) -# define DBG_raw(fmt, args...) do { fprintf(stderr, fmt, ## args); } while(0) +# define DBG(fmt, args...) ERRMSG(fmt, ## args) +# define DBG_raw(fmt, args...) \ + do { \ + fprintf(stderr, fmt, ## args); \ + } while(0) #else -# define DBG(fmt, args...) __check_ust_safe_fmt(fmt, ## args) -# define DBG_raw(fmt, args...) __check_ust_safe_fmt(fmt, ## args) +# define DBG(fmt, args...) \ + do { \ + if (ust_debug()) \ + ERRMSG(fmt, ## args); \ + } while (0) +# define DBG_raw(fmt, args...) \ + do { \ + if (ust_debug()) { \ + fprintf(stderr, fmt, ## args); \ + } \ + } while(0) #endif + #define WARN(fmt, args...) ERRMSG("Warning: " fmt, ## args) #define ERR(fmt, args...) ERRMSG("Error: " fmt, ## args) #define BUG(fmt, args...) ERRMSG("BUG: " fmt, ## args) @@ -75,8 +105,16 @@ static inline void __attribute__ ((format (printf, 1, 2))) } while(0); #endif -#define BUG_ON(condition) do { if (unlikely(condition)) ERR("condition not respected (BUG)"); } while(0) -#define WARN_ON(condition) do { if (unlikely(condition)) WARN("condition not respected on line %s:%d", __FILE__, __LINE__); } while(0) +#define BUG_ON(condition) \ + do { \ + if (unlikely(condition)) \ + ERR("condition not respected (BUG) on line %s:%d", __FILE__, __LINE__); \ + } while(0) +#define WARN_ON(condition) \ + do { \ + if (unlikely(condition)) \ + WARN("condition not respected on line %s:%d", __FILE__, __LINE__); \ + } while(0) #define WARN_ON_ONCE(condition) WARN_ON(condition) #endif /* _USTERR_H */ diff --git a/include/usterr_signal_safe.h b/include/usterr_signal_safe.h index 10355dcb..77f9d5fc 100644 --- a/include/usterr_signal_safe.h +++ b/include/usterr_signal_safe.h @@ -1,9 +1,14 @@ -/* Copyright (C) 2009 Pierre-Marc Fournier +#ifndef _USTERR_SIGNAL_SAFE_H +#define _USTERR_SIGNAL_SAFE_H + +/* + * Copyright (C) 2009 Pierre-Marc Fournier + * Copyright (C) 2011 Mathieu Desnoyers * * 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. + * License as published by the Free Software Foundation; version 2.1 of + * the License. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of @@ -15,9 +20,6 @@ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ -#ifndef _USTERR_SIGNAL_SAFE_H -#define _USTERR_SIGNAL_SAFE_H - #include #include #include @@ -29,6 +31,20 @@ #include "share.h" +enum ust_loglevel { + UST_LOGLEVEL_UNKNOWN = 0, + UST_LOGLEVEL_NORMAL, + UST_LOGLEVEL_DEBUG, +}; + +extern volatile enum ust_loglevel ust_loglevel; +void init_usterr(void); + +static inline int ust_debug(void) +{ + return ust_loglevel == UST_LOGLEVEL_DEBUG; +} + #ifndef UST_COMPONENT //#error UST_COMPONENT is undefined #define UST_COMPONENT libust @@ -50,37 +66,61 @@ static inline void __attribute__ ((format (printf, 1, 2))) { } -#define sigsafe_print_err(fmt, args...) \ -{ \ +#define sigsafe_print_err(fmt, args...) \ +{ \ /* Can't use dynamic allocation. Limit ourselves to 250 chars. */ \ - char ____buf[250]; \ - int ____saved_errno; \ -\ - /* Save the errno. */ \ - ____saved_errno = errno; \ -\ - ust_safe_snprintf(____buf, sizeof(____buf), fmt, ## args); \ -\ - /* Add end of string in case of buffer overflow. */ \ - ____buf[sizeof(____buf) - 1] = 0; \ -\ - patient_write(STDERR_FILENO, ____buf, strlen(____buf)); \ - /* Can't print errors because we are in the error printing code path. */ \ -\ - /* Restore errno, in order to be async-signal safe. */ \ - errno = ____saved_errno; \ + char ____buf[250]; \ + int ____saved_errno; \ + \ + /* Save the errno. */ \ + ____saved_errno = errno; \ + \ + ust_safe_snprintf(____buf, sizeof(____buf), fmt, ## args); \ + \ + /* Add end of string in case of buffer overflow. */ \ + ____buf[sizeof(____buf) - 1] = 0; \ + \ + patient_write(STDERR_FILENO, ____buf, strlen(____buf)); \ + /* \ + * Can't print errors because we are in the error printing code \ + * path. \ + */ \ + \ + /* Restore errno, in order to be async-signal safe. */ \ + errno = ____saved_errno; \ } #define UST_STR_COMPONENT XSTR(UST_COMPONENT) -#define ERRMSG(fmt, args...) do { sigsafe_print_err(UST_STR_COMPONENT "[%ld/%ld]: " fmt " (in %s() at " __FILE__ ":" XSTR(__LINE__) ")\n", (long) getpid(), (long) syscall(SYS_gettid), ## args, __func__); fflush(stderr); } while(0) +#define ERRMSG(fmt, args...) \ + do { \ + sigsafe_print_err(UST_STR_COMPONENT "[%ld/%ld]: " fmt " (in %s() at " __FILE__ ":" XSTR(__LINE__) ")\n", \ + (long) getpid(), \ + (long) syscall(SYS_gettid), \ + ## args, __func__); \ + fflush(stderr); \ + } while(0) #ifdef UST_DEBUG -# define DBG(fmt, args...) ERRMSG(fmt, ## args) -# define DBG_raw(fmt, args...) do { sigsafe_print_err(fmt, ## args); fflush(stderr); } while(0) +# define DBG(fmt, args...) ERRMSG(fmt, ## args) +# define DBG_raw(fmt, args...) \ + do { \ + sigsafe_print_err(fmt, ## args); \ + fflush(stderr); \ + } while(0) #else -# define DBG(fmt, args...) __check_ust_safe_fmt(fmt, ## args) -# define DBG_raw(fmt, args...) __check_ust_safe_fmt(fmt, ## args) +# define DBG(fmt, args...) \ + do { \ + if (ust_debug()) \ + ERRMSG(fmt, ## args); \ + } while (0) +# define DBG_raw(fmt, args...) \ + do { \ + if (ust_debug()) { \ + sigsafe_print_err(fmt, ## args); \ + fflush(stderr); \ + } \ + } while(0) #endif #define WARN(fmt, args...) ERRMSG("Warning: " fmt, ## args) #define ERR(fmt, args...) ERRMSG("Error: " fmt, ## args) @@ -103,8 +143,17 @@ static inline void __attribute__ ((format (printf, 1, 2))) } while(0); #endif -#define BUG_ON(condition) do { if (unlikely(condition)) ERR("condition not respected (BUG)"); } while(0) -#define WARN_ON(condition) do { if (unlikely(condition)) WARN("condition not respected on line %s:%d", __FILE__, __LINE__); } while(0) +#define BUG_ON(condition) \ + do { \ + if (unlikely(condition)) \ + ERR("condition not respected (BUG) on line %s:%d", __FILE__, __LINE__); \ + } while(0) +#define WARN_ON(condition) \ + do { \ + if (unlikely(condition)) \ + WARN("condition not respected on line %s:%d", __FILE__, __LINE__); \ + } while(0) #define WARN_ON_ONCE(condition) WARN_ON(condition) + #endif /* _USTERR_SIGNAL_SAFE_H */ diff --git a/libust/Makefile.am b/libust/Makefile.am index 957565d0..0fa4a2b5 100644 --- a/libust/Makefile.am +++ b/libust/Makefile.am @@ -16,7 +16,8 @@ libust_la_SOURCES = \ ltt-context.c \ ltt-probes.c \ lttng-ust-abi.c \ - lttng-ust-comm.c + lttng-ust-comm.c \ + ust-core.c #removed: buffers.c buffers.h diff --git a/libust/buffers.c b/libust/buffers.c index 9f06ae2d..c4eddb06 100644 --- a/libust/buffers.c +++ b/libust/buffers.c @@ -1056,6 +1056,7 @@ static char initialized = 0; void __attribute__((constructor)) init_ustrelay_transport(void) { + init_usterr(); if(!initialized) { ltt_transport_register(&ust_relay_transport); initialized = 1; diff --git a/libust/lttng-ust-abi.c b/libust/lttng-ust-abi.c index 31eaa2a7..ad582c05 100644 --- a/libust/lttng-ust-abi.c +++ b/libust/lttng-ust-abi.c @@ -706,6 +706,7 @@ static const struct objd_ops lttng_event_ops = { void __attribute__((constructor)) lttng_ust_abi_init(void) { + init_usterr(); /* TODO: initialize socket */ } diff --git a/libust/tracepoint.c b/libust/tracepoint.c index 3bc5795a..67619a85 100644 --- a/libust/tracepoint.c +++ b/libust/tracepoint.c @@ -690,6 +690,7 @@ int tracepoint_unregister_lib(struct tracepoint * const *tracepoints_start) void __attribute__((constructor)) init_tracepoint(void) { + init_usterr(); if (!initialized) { tracepoint_register_lib(__start___tracepoints_ptrs, __stop___tracepoints_ptrs diff --git a/libust/ust-core.c b/libust/ust-core.c new file mode 100644 index 00000000..7791ffb0 --- /dev/null +++ b/libust/ust-core.c @@ -0,0 +1,37 @@ +/* + * ust-core.c + * + * Copyright (C) 2011 Mathieu Desnoyers + * + * 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; only + * version 2.1 of the License. + * + * 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 + */ + +#include +#include + +volatile enum ust_loglevel ust_loglevel; + +void init_usterr(void) +{ + char *ust_debug; + + if (ust_loglevel == UST_LOGLEVEL_UNKNOWN) { + ust_debug = getenv("UST_DEBUG"); + if (ust_debug) + ust_loglevel = UST_LOGLEVEL_DEBUG; + else + ust_loglevel = UST_LOGLEVEL_NORMAL; + } +} -- 2.34.1