]>
Commit | Line | Data |
---|---|---|
fe7f9ed9 JK |
1 | # |
2 | # gdb helper commands and functions for Linux kernel debugging | |
3 | # | |
4 | # per-cpu tools | |
5 | # | |
6 | # Copyright (c) Siemens AG, 2011-2013 | |
7 | # | |
8 | # Authors: | |
9 | # Jan Kiszka <jan.kiszka@siemens.com> | |
10 | # | |
11 | # This work is licensed under the terms of the GNU GPL version 2. | |
12 | # | |
13 | ||
14 | import gdb | |
15 | ||
16 | from linux import tasks, utils | |
17 | ||
18 | ||
19 | MAX_CPUS = 4096 | |
20 | ||
21 | ||
22 | def get_current_cpu(): | |
23 | if utils.get_gdbserver_type() == utils.GDBSERVER_QEMU: | |
24 | return gdb.selected_thread().num - 1 | |
25 | elif utils.get_gdbserver_type() == utils.GDBSERVER_KGDB: | |
26 | tid = gdb.selected_thread().ptid[2] | |
27 | if tid > (0x100000000 - MAX_CPUS - 2): | |
28 | return 0x100000000 - tid - 2 | |
29 | else: | |
30 | return tasks.get_thread_info(tasks.get_task_by_pid(tid))['cpu'] | |
31 | else: | |
32 | raise gdb.GdbError("Sorry, obtaining the current CPU is not yet " | |
33 | "supported with this gdb server.") | |
34 | ||
35 | ||
36 | def per_cpu(var_ptr, cpu): | |
37 | if cpu == -1: | |
38 | cpu = get_current_cpu() | |
39 | if utils.is_target_arch("sparc:v9"): | |
40 | offset = gdb.parse_and_eval( | |
41 | "trap_block[{0}].__per_cpu_base".format(str(cpu))) | |
42 | else: | |
43 | try: | |
44 | offset = gdb.parse_and_eval( | |
45 | "__per_cpu_offset[{0}]".format(str(cpu))) | |
46 | except gdb.error: | |
47 | # !CONFIG_SMP case | |
48 | offset = 0 | |
49 | pointer = var_ptr.cast(utils.get_long_type()) + offset | |
50 | return pointer.cast(var_ptr.type).dereference() | |
51 | ||
52 | ||
3d4cd9c9 JK |
53 | cpu_mask = {} |
54 | ||
55 | ||
56 | def cpu_mask_invalidate(event): | |
57 | global cpu_mask | |
58 | cpu_mask = {} | |
59 | gdb.events.stop.disconnect(cpu_mask_invalidate) | |
60 | if hasattr(gdb.events, 'new_objfile'): | |
61 | gdb.events.new_objfile.disconnect(cpu_mask_invalidate) | |
62 | ||
63 | ||
a77e15e8 JK |
64 | def cpu_list(mask_name): |
65 | global cpu_mask | |
66 | mask = None | |
67 | if mask_name in cpu_mask: | |
68 | mask = cpu_mask[mask_name] | |
69 | if mask is None: | |
70 | mask = gdb.parse_and_eval(mask_name + ".bits") | |
71 | if hasattr(gdb, 'events'): | |
72 | cpu_mask[mask_name] = mask | |
73 | gdb.events.stop.connect(cpu_mask_invalidate) | |
74 | if hasattr(gdb.events, 'new_objfile'): | |
75 | gdb.events.new_objfile.connect(cpu_mask_invalidate) | |
76 | bits_per_entry = mask[0].type.sizeof * 8 | |
77 | num_entries = mask.type.sizeof * 8 / bits_per_entry | |
78 | entry = -1 | |
79 | bits = 0 | |
80 | ||
81 | while True: | |
82 | while bits == 0: | |
83 | entry += 1 | |
84 | if entry == num_entries: | |
85 | return | |
86 | bits = mask[entry] | |
87 | if bits != 0: | |
88 | bit = 0 | |
3d4cd9c9 JK |
89 | break |
90 | ||
a77e15e8 JK |
91 | while bits & 1 == 0: |
92 | bits >>= 1 | |
93 | bit += 1 | |
3d4cd9c9 | 94 | |
a77e15e8 | 95 | cpu = entry * bits_per_entry + bit |
3d4cd9c9 | 96 | |
a77e15e8 JK |
97 | bits >>= 1 |
98 | bit += 1 | |
3d4cd9c9 | 99 | |
4bc393db | 100 | yield int(cpu) |
276d97d9 | 101 | |
3d4cd9c9 | 102 | |
b1503934 KB |
103 | def each_online_cpu(): |
104 | for cpu in cpu_list("__cpu_online_mask"): | |
105 | yield cpu | |
106 | ||
107 | ||
108 | def each_present_cpu(): | |
109 | for cpu in cpu_list("__cpu_present_mask"): | |
110 | yield cpu | |
111 | ||
112 | ||
113 | def each_possible_cpu(): | |
114 | for cpu in cpu_list("__cpu_possible_mask"): | |
115 | yield cpu | |
116 | ||
117 | ||
118 | def each_active_cpu(): | |
119 | for cpu in cpu_list("__cpu_active_mask"): | |
120 | yield cpu | |
121 | ||
122 | ||
123 | class LxCpus(gdb.Command): | |
124 | """List CPU status arrays | |
125 | ||
126 | Displays the known state of each CPU based on the kernel masks | |
127 | and can help identify the state of hotplugged CPUs""" | |
128 | ||
129 | def __init__(self): | |
130 | super(LxCpus, self).__init__("lx-cpus", gdb.COMMAND_DATA) | |
131 | ||
132 | def invoke(self, arg, from_tty): | |
133 | gdb.write("Possible CPUs : {}\n".format(list(each_possible_cpu()))) | |
134 | gdb.write("Present CPUs : {}\n".format(list(each_present_cpu()))) | |
135 | gdb.write("Online CPUs : {}\n".format(list(each_online_cpu()))) | |
136 | gdb.write("Active CPUs : {}\n".format(list(each_active_cpu()))) | |
137 | ||
138 | LxCpus() | |
139 | ||
140 | ||
fe7f9ed9 JK |
141 | class PerCpu(gdb.Function): |
142 | """Return per-cpu variable. | |
143 | ||
144 | $lx_per_cpu("VAR"[, CPU]): Return the per-cpu variable called VAR for the | |
145 | given CPU number. If CPU is omitted, the CPU of the current context is used. | |
146 | Note that VAR has to be quoted as string.""" | |
147 | ||
148 | def __init__(self): | |
149 | super(PerCpu, self).__init__("lx_per_cpu") | |
150 | ||
151 | def invoke(self, var_name, cpu=-1): | |
152 | var_ptr = gdb.parse_and_eval("&" + var_name.string()) | |
153 | return per_cpu(var_ptr, cpu) | |
154 | ||
155 | ||
156 | PerCpu() | |
116b47b4 JK |
157 | |
158 | ||
159 | class LxCurrentFunc(gdb.Function): | |
160 | """Return current task. | |
161 | ||
162 | $lx_current([CPU]): Return the per-cpu task variable for the given CPU | |
163 | number. If CPU is omitted, the CPU of the current context is used.""" | |
164 | ||
165 | def __init__(self): | |
166 | super(LxCurrentFunc, self).__init__("lx_current") | |
167 | ||
168 | def invoke(self, cpu=-1): | |
169 | var_ptr = gdb.parse_and_eval("¤t_task") | |
170 | return per_cpu(var_ptr, cpu).dereference() | |
171 | ||
172 | ||
173 | LxCurrentFunc() |