| 1 | /* |
| 2 | * Copyright (C) 2012 - Christian Babeux <christian.babeux@efficios.com> |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or modify it |
| 5 | * under the terms of the GNU General Public License, version 2 only, as |
| 6 | * published by the Free Software Foundation. |
| 7 | * |
| 8 | * This program is distributed in the hope that it will be useful, but WITHOUT |
| 9 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 10 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for |
| 11 | * more details. |
| 12 | * |
| 13 | * You should have received a copy of the GNU General Public License along with |
| 14 | * this program; if not, write to the Free Software Foundation, Inc., 51 |
| 15 | * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
| 16 | */ |
| 17 | |
| 18 | #ifdef NTESTPOINT |
| 19 | |
| 20 | #define testpoint(name) |
| 21 | #define TESTPOINT_DECL(name) |
| 22 | |
| 23 | #else /* NTESTPOINT */ |
| 24 | |
| 25 | #include <urcu.h> /* for caa_likely/unlikely */ |
| 26 | |
| 27 | extern int lttng_testpoint_activated; |
| 28 | |
| 29 | void *lttng_testpoint_lookup(const char *name); |
| 30 | |
| 31 | /* |
| 32 | * Testpoint is only active if the global lttng_testpoint_activated flag is |
| 33 | * set. |
| 34 | * Return a non-zero error code to indicate failure. |
| 35 | */ |
| 36 | #define testpoint(name) \ |
| 37 | ((caa_unlikely(lttng_testpoint_activated)) \ |
| 38 | ? __testpoint_##name##_wrapper() : 0) |
| 39 | |
| 40 | /* |
| 41 | * One wrapper per testpoint is generated. This is to keep track of the symbol |
| 42 | * lookup status and the corresponding function pointer, if any. |
| 43 | */ |
| 44 | #define _TESTPOINT_DECL(_name) \ |
| 45 | static inline int __testpoint_##_name##_wrapper(void) \ |
| 46 | { \ |
| 47 | int ret = 0; \ |
| 48 | static int (*tp)(void); \ |
| 49 | static int found; \ |
| 50 | const char *tp_name = "__testpoint_" #_name; \ |
| 51 | \ |
| 52 | if (tp) { \ |
| 53 | ret = tp(); \ |
| 54 | } else { \ |
| 55 | if (!found) { \ |
| 56 | tp = lttng_testpoint_lookup(tp_name); \ |
| 57 | if (tp) { \ |
| 58 | found = 1; \ |
| 59 | ret = tp(); \ |
| 60 | } else { \ |
| 61 | found = -1; \ |
| 62 | } \ |
| 63 | } \ |
| 64 | } \ |
| 65 | return ret; \ |
| 66 | } |
| 67 | |
| 68 | /* Testpoint declaration */ |
| 69 | #define TESTPOINT_DECL(name) \ |
| 70 | _TESTPOINT_DECL(name) |
| 71 | |
| 72 | #endif /* NTESTPOINT */ |