1 // SPDX-License-Identifier: GPL-2.0 2 #define CREATE_TRACE_POINTS 3 #include <trace/events/mmap_lock.h> 4 5 #include <linux/mm.h> 6 #include <linux/cgroup.h> 7 #include <linux/memcontrol.h> 8 #include <linux/mmap_lock.h> 9 #include <linux/mutex.h> 10 #include <linux/percpu.h> 11 #include <linux/rcupdate.h> 12 #include <linux/smp.h> 13 #include <linux/trace_events.h> 14 #include <linux/local_lock.h> 15 16 EXPORT_TRACEPOINT_SYMBOL(mmap_lock_start_locking); 17 EXPORT_TRACEPOINT_SYMBOL(mmap_lock_acquire_returned); 18 EXPORT_TRACEPOINT_SYMBOL(mmap_lock_released); 19 20 #ifdef CONFIG_MEMCG 21 22 /* 23 * Size of the buffer for memcg path names. Ignoring stack trace support, 24 * trace_events_hist.c uses MAX_FILTER_STR_VAL for this, so we also use it. 25 */ 26 #define MEMCG_PATH_BUF_SIZE MAX_FILTER_STR_VAL 27 28 #define TRACE_MMAP_LOCK_EVENT(type, mm, ...) \ 29 do { \ 30 if (trace_mmap_lock_##type##_enabled()) { \ 31 char buf[MEMCG_PATH_BUF_SIZE]; \ 32 get_mm_memcg_path(mm, buf, sizeof(buf)); \ 33 trace_mmap_lock_##type(mm, buf, ##__VA_ARGS__); \ 34 } \ 35 } while (0) 36 37 #else /* !CONFIG_MEMCG */ 38 39 #define TRACE_MMAP_LOCK_EVENT(type, mm, ...) \ 40 trace_mmap_lock_##type(mm, "", ##__VA_ARGS__) 41 42 #endif /* CONFIG_MEMCG */ 43 44 #ifdef CONFIG_TRACING 45 #ifdef CONFIG_MEMCG 46 /* 47 * Write the given mm_struct's memcg path to a buffer. If the path cannot be 48 * determined, empty string is written. 49 */ 50 static void get_mm_memcg_path(struct mm_struct *mm, char *buf, size_t buflen) 51 { 52 struct mem_cgroup *memcg; 53 54 buf[0] = '\0'; 55 memcg = get_mem_cgroup_from_mm(mm); 56 if (memcg == NULL) 57 return; 58 if (memcg->css.cgroup) 59 cgroup_path(memcg->css.cgroup, buf, buflen); 60 css_put(&memcg->css); 61 } 62 63 #endif /* CONFIG_MEMCG */ 64 65 /* 66 * Trace calls must be in a separate file, as otherwise there's a circular 67 * dependency between linux/mmap_lock.h and trace/events/mmap_lock.h. 68 */ 69 70 void __mmap_lock_do_trace_start_locking(struct mm_struct *mm, bool write) 71 { 72 TRACE_MMAP_LOCK_EVENT(start_locking, mm, write); 73 } 74 EXPORT_SYMBOL(__mmap_lock_do_trace_start_locking); 75 76 void __mmap_lock_do_trace_acquire_returned(struct mm_struct *mm, bool write, 77 bool success) 78 { 79 TRACE_MMAP_LOCK_EVENT(acquire_returned, mm, write, success); 80 } 81 EXPORT_SYMBOL(__mmap_lock_do_trace_acquire_returned); 82 83 void __mmap_lock_do_trace_released(struct mm_struct *mm, bool write) 84 { 85 TRACE_MMAP_LOCK_EVENT(released, mm, write); 86 } 87 EXPORT_SYMBOL(__mmap_lock_do_trace_released); 88 #endif /* CONFIG_TRACING */ 89