projects / lttng-modules.git / blame
| Commit | Line | Data |
|---|---|---|
| 42d9070d AG |
1 | #ifndef _LTTNG_WRAPPER_WRITEBACK_H |
| 2 | #define _LTTNG_WRAPPER_WRITEBACK_H | |
| 3 | ||
| 4 | /* | |
| 5 | * wrapper/writeback.h | |
| 6 | * | |
| 7 | * wrapper around global_dirty_limit read. Using KALLSYMS with KALLSYMS_ALL | |
| 8 | * to get its address when available, else we need to have a kernel that | |
| 9 | * exports this variable to GPL modules. | |
| 10 | * | |
| 11 | * Copyright (C) 2013 Mentor Graphics Corp. | |
| 12 | * | |
| 13 | * This library is free software; you can redistribute it and/or | |
| 14 | * modify it under the terms of the GNU Lesser General Public | |
| 15 | * License as published by the Free Software Foundation; only | |
| 16 | * version 2.1 of the License. | |
| 17 | * | |
| 18 | * This library is distributed in the hope that it will be useful, | |
| 19 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 20 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 21 | * Lesser General Public License for more details. | |
| 22 | * | |
| 23 | * You should have received a copy of the GNU Lesser General Public | |
| 24 | * License along with this library; if not, write to the Free Software | |
| 25 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | |
| 26 | */ | |
| 27 | ||
| 28 | #ifdef CONFIG_KALLSYMS_ALL | |
| 29 | ||
| 30 | #include <linux/kallsyms.h> | |
| 31 | #include "kallsyms.h" | |
| 32 | ||
| 33 | static unsigned long *global_dirty_limit_sym; | |
| 34 | ||
| 35 | static inline | |
| 36 | unsigned long wrapper_global_dirty_limit(void) | |
| 37 | { | |
| 38 | if (!global_dirty_limit_sym) | |
| 39 | global_dirty_limit_sym = | |
| 40 | (void *) kallsyms_lookup_dataptr("global_dirty_limit"); | |
| 41 | if (global_dirty_limit_sym) { | |
| 42 | return *global_dirty_limit_sym; | |
| 43 | } else { | |
| 44 | printk(KERN_WARNING "LTTng: global_dirty_limit symbol lookup failed.\n"); | |
| 45 | return 0; | |
| 46 | } | |
| 47 | } | |
| 48 | ||
| 49 | #else | |
| 50 | ||
| 51 | #include <linux/writeback.h> | |
| 52 | ||
| 53 | static inline | |
| 54 | unsigned long wrapper_global_dirty_limit(void) | |
| 55 | { | |
| 56 | return global_dirty_limit; | |
| 57 | } | |
| 58 | ||
| 59 | #endif | |
| 60 | ||
| 61 | #endif /* _LTTNG_WRAPPER_WRITEBACK_H */ |