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 | ||
| 6284ae7c | 28 | #include <lttng-kernel-version.h> |
| 42d9070d | 29 | |
| 6284ae7c | 30 | #ifdef CONFIG_KALLSYMS_ALL |
| 42d9070d | 31 | #include <linux/kallsyms.h> |
| 5a2f5e92 | 32 | #include <wrapper/kallsyms.h> |
| 42d9070d | 33 | |
| 6284ae7c MJ |
34 | |
| 35 | ||
| 36 | #if LINUX_VERSION_CODE >= KERNEL_VERSION(4,2,0) | |
| 37 | ||
| 38 | static struct wb_domain *global_wb_domain_sym; | |
| 39 | ||
| 40 | static inline | |
| 41 | unsigned long wrapper_global_dirty_limit(void) | |
| 42 | { | |
| 43 | if (!global_wb_domain_sym) | |
| 44 | global_wb_domain_sym = | |
| 45 | (void *) kallsyms_lookup_dataptr("global_wb_domain"); | |
| 46 | if (global_wb_domain_sym) { | |
| 47 | return global_wb_domain_sym->dirty_limit; | |
| 48 | } else { | |
| 49 | printk_once(KERN_WARNING "LTTng: global_wb_domain symbol lookup failed.\n"); | |
| 50 | return 0; | |
| 51 | } | |
| 52 | } | |
| 53 | #else | |
| 54 | ||
| 42d9070d AG |
55 | static unsigned long *global_dirty_limit_sym; |
| 56 | ||
| 57 | static inline | |
| 58 | unsigned long wrapper_global_dirty_limit(void) | |
| 59 | { | |
| 60 | if (!global_dirty_limit_sym) | |
| 61 | global_dirty_limit_sym = | |
| 62 | (void *) kallsyms_lookup_dataptr("global_dirty_limit"); | |
| 63 | if (global_dirty_limit_sym) { | |
| 64 | return *global_dirty_limit_sym; | |
| 65 | } else { | |
| e36de50d | 66 | printk_once(KERN_WARNING "LTTng: global_dirty_limit symbol lookup failed.\n"); |
| 42d9070d AG |
67 | return 0; |
| 68 | } | |
| 69 | } | |
| 6284ae7c | 70 | #endif |
| 42d9070d | 71 | |
| 6284ae7c | 72 | #else /* CONFIG_KALLSYMS_ALL */ |
| 42d9070d AG |
73 | |
| 74 | #include <linux/writeback.h> | |
| 75 | ||
| 76 | static inline | |
| 77 | unsigned long wrapper_global_dirty_limit(void) | |
| 78 | { | |
| 79 | return global_dirty_limit; | |
| 80 | } | |
| 81 | ||
| 82 | #endif | |
| 83 | ||
| 84 | #endif /* _LTTNG_WRAPPER_WRITEBACK_H */ |