1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
|
// SPDX-License-Identifier: GPL-2.0
#define CREATE_TRACE_POINTS
#include <trace/events/mmap_lock.h>
#include <linux/mm.h>
#include <linux/cgroup.h>
#include <linux/memcontrol.h>
#include <linux/mmap_lock.h>
#include <linux/mutex.h>
#include <linux/percpu.h>
#include <linux/rcupdate.h>
#include <linux/smp.h>
#include <linux/trace_events.h>
#include <linux/local_lock.h>
EXPORT_TRACEPOINT_SYMBOL(mmap_lock_start_locking);
EXPORT_TRACEPOINT_SYMBOL(mmap_lock_acquire_returned);
EXPORT_TRACEPOINT_SYMBOL(mmap_lock_released);
#ifdef CONFIG_MEMCG
static atomic_t reg_refcount;
/*
* Size of the buffer for memcg path names. Ignoring stack trace support,
* trace_events_hist.c uses MAX_FILTER_STR_VAL for this, so we also use it.
*/
#define MEMCG_PATH_BUF_SIZE MAX_FILTER_STR_VAL
int trace_mmap_lock_reg(void)
{
atomic_inc(®_refcount);
return 0;
}
void trace_mmap_lock_unreg(void)
{
atomic_dec(®_refcount);
}
#define TRACE_MMAP_LOCK_EVENT(type, mm, ...) \
do { \
char buf[MEMCG_PATH_BUF_SIZE]; \
get_mm_memcg_path(mm, buf, sizeof(buf)); \
trace_mmap_lock_##type(mm, buf, ##__VA_ARGS__); \
} while (0)
#else /* !CONFIG_MEMCG */
int trace_mmap_lock_reg(void)
{
return 0;
}
void trace_mmap_lock_unreg(void)
{
}
#define TRACE_MMAP_LOCK_EVENT(type, mm, ...) \
trace_mmap_lock_##type(mm, "", ##__VA_ARGS__)
#endif /* CONFIG_MEMCG */
#ifdef CONFIG_TRACING
#ifdef CONFIG_MEMCG
/*
* Write the given mm_struct's memcg path to a buffer. If the path cannot be
* determined or the trace event is being unregistered, empty string is written.
*/
static void get_mm_memcg_path(struct mm_struct *mm, char *buf, size_t buflen)
{
struct mem_cgroup *memcg;
buf[0] = '\0';
/* No need to get path if no trace event is registered. */
if (!atomic_read(®_refcount))
return;
memcg = get_mem_cgroup_from_mm(mm);
if (memcg == NULL)
return;
if (memcg->css.cgroup)
cgroup_path(memcg->css.cgroup, buf, buflen);
css_put(&memcg->css);
}
#endif /* CONFIG_MEMCG */
/*
* Trace calls must be in a separate file, as otherwise there's a circular
* dependency between linux/mmap_lock.h and trace/events/mmap_lock.h.
*/
void __mmap_lock_do_trace_start_locking(struct mm_struct *mm, bool write)
{
TRACE_MMAP_LOCK_EVENT(start_locking, mm, write);
}
EXPORT_SYMBOL(__mmap_lock_do_trace_start_locking);
void __mmap_lock_do_trace_acquire_returned(struct mm_struct *mm, bool write,
bool success)
{
TRACE_MMAP_LOCK_EVENT(acquire_returned, mm, write, success);
}
EXPORT_SYMBOL(__mmap_lock_do_trace_acquire_returned);
void __mmap_lock_do_trace_released(struct mm_struct *mm, bool write)
{
TRACE_MMAP_LOCK_EVENT(released, mm, write);
}
EXPORT_SYMBOL(__mmap_lock_do_trace_released);
#endif /* CONFIG_TRACING */
|
