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
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
|
// memory/vm related tapset
// Copyright (C) 2005, 2006 IBM Corp.
// Copyright (C) 2006 Intel Corporation.
//
// This file is part of systemtap, and is free software. You can
// redistribute it and/or modify it under the terms of the GNU General
// Public License (GPL); either version 2, or (at your option) any
// later version.
// <tapsetdescription>
// This family of probe points is used to probe memory-related events.
// </tapsetdescription>
%{
#include <linux/mm.h>
%}
global VM_FAULT_OOM=0, VM_FAULT_SIGBUS=1, VM_FAULT_MINOR=2, VM_FAULT_MAJOR=3
global VM_FAULT_NOPAGE=4, VM_FAULT_LOCKED=5, VM_FAULT_ERROR=6
/**
* sfunction vm_fault_contains - Test return value for page fault reason
* @value: The fault_type returned by vm.page_fault.return
* @test: The type of fault to test for (VM_FAULT_OOM or similar)
*/
function vm_fault_contains:long (value:long, test:long)
%{
int res;
#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
switch (THIS->test){
case 0: res = THIS->value == VM_FAULT_OOM; break;
case 1: res = THIS->value == VM_FAULT_SIGBUS; break;
case 2: res = THIS->value == VM_FAULT_MINOR; break;
case 3: res = THIS->value == VM_FAULT_MAJOR; break;
default:
res = 0; break;
}
#else
switch (THIS->test){
case 0: res = THIS->value & VM_FAULT_OOM; break;
case 1: res = THIS->value & VM_FAULT_SIGBUS; break;
case 2: /* VM_FAULT_MINOR infered by that flags off */
res = !((VM_FAULT_OOM | VM_FAULT_SIGBUS | VM_FAULT_MAJOR) &
THIS->value);
break;
case 3: res = THIS->value & VM_FAULT_MAJOR; break;
case 4: res = THIS->value & VM_FAULT_NOPAGE; break;
case 5: res = THIS->value & VM_FAULT_LOCKED; break;
case 6: res = THIS->value & VM_FAULT_ERROR; break;
default:
res = 0;
}
#endif
THIS->__retvalue = (res != 0);
return;
%}
/**
* probe vm.pagefault - Records that a page fault occurred.
* @address: The address of the faulting memory access; i.e. the address that caused the page fault.
* @write_access: Indicates whether this was a write or read access; <command>1</command> indicates a write,
* while <command>0</command> indicates a read.
*
* Context: The process which triggered the fault
*/
probe vm.pagefault = kernel.function("__handle_mm_fault@mm/memory.c") ?,
kernel.function("handle_mm_fault@mm/memory.c") ?
{
write_access = $write_access
address = $address
}
/**
* probe vm.pagefault.return - Indicates what type of fault occurred.
* @fault_type: Returns either
* <command>0</command> (VM_FAULT_OOM) for out of memory faults,
* <command>2</command> (VM_FAULT_MINOR) for minor faults, <command>3</command> (VM_FAULT_MAJOR) for
* major faults, or <command>1</command> (VM_FAULT_SIGBUS) if the fault was neither OOM, minor fault,
* nor major fault.
*/
probe vm.pagefault.return = kernel.function("__handle_mm_fault@mm/memory.c").return ?,
kernel.function("handle_mm_fault@mm/memory.c").return ?
{
fault_type = $return
}
/**
* sfunction addr_to_node - Returns which node a given address belongs to within a NUMA system.
* @addr: The address of the faulting memory access.
*
*/
function addr_to_node:long(addr:long) %{ /* pure */
int nid;
int pfn = __pa(THIS->addr) >> PAGE_SHIFT;
for_each_online_node(nid)
if ( NODE_DATA(nid)->node_start_pfn <= pfn &&
pfn < (NODE_DATA(nid)->node_start_pfn +
NODE_DATA(nid)->node_spanned_pages) )
{
THIS->__retvalue = nid;
break;
}
%}
// Return whether a page to be copied is a zero page.
function _IS_ZERO_PAGE:long(from:long, vaddr:long) %{ /* pure */
THIS->__retvalue = (THIS->from == (long) ZERO_PAGE(THIS->vaddr));
%}
/**
* probe vm.write_shared - Attempts at writing to a shared page.
* @address: The address of the shared write.
*
* Context:
* The context is the process attempting the write.
*
* Fires when a process attempts to write to a shared page.
* If a copy is necessary, this will be followed by a
* <command>vm.write_shared_copy</command>.
*/
probe vm.write_shared = kernel.function("do_wp_page") {
address = $address
}
/**
* probe vm.write_shared_copy - Page copy for shared page write.
* @address: The address of the shared write.
* @zero: Boolean indicating whether it is a zero page
* (can do a clear instead of a copy).
*
* Context:
* The process attempting the write.
*
* Fires when a write to a shared page requires a page copy. This is
* always preceded by a <command>vm.shared_write</command>.
*/
probe vm.write_shared_copy = kernel.function("copy_cow_page")? {
address = $address
zero = _IS_ZERO_PAGE($from, address);
}
/**
* probe vm.mmap - Fires when an <command>mmap</command> is requested.
* @address: The requested address
* @length: The length of the memory segment
*
* Context:
* The process calling <command>mmap</command>.
*/
probe vm.mmap = kernel.function("do_mmap"), kernel.function("do_mmap2")? {
address = $addr
length = $len
}
/**
* probe vm.munmap - Fires when an <command>munmap</command> is requested.
* @address: The requested address
* @length: The length of the memory segment
*
* Context:
* The process calling <command>munmap</command>.
*/
probe vm.munmap = kernel.function("do_munmap") {
address = $start
length = $len
}
/**
* probe vm.brk - Fires when a <command>brk</command> is requested (i.e. the heap will be resized).
* @address: The requested address
* @length: The length of the memory segment
*
* Context:
* The process calling <command>brk</command>.
*/
probe vm.brk = kernel.function("do_brk") {
address = $addr
length = $len
}
/**
* probe vm.oom_kill - Fires when a thread is selected for termination by the OOM killer.
* @task: The task being killed
*
* Context:
* The process that tried to consume excessive memory, and thus
* triggered the OOM. <remark>(is this correct?)</remark>
*/
probe vm.oom_kill = kernel.function("__oom_kill_task") {
task = $p
}
|