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1/*
2 * Code for replacing ftrace calls with jumps.
3 *
4 * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com>
5 * Copyright (C) 2009, 2010 DSLab, Lanzhou University, China
6 * Author: Wu Zhangjin <wuzhangjin@gmail.com>
7 *
8 * Thanks goes to Steven Rostedt for writing the original x86 version.
9 */
10
11#include <linux/uaccess.h>
12#include <linux/init.h>
13#include <linux/ftrace.h>
14
15#include <asm/asm.h>
16#include <asm/asm-offsets.h>
17#include <asm/cacheflush.h>
18#include <asm/uasm.h>
19
20#include <asm-generic/sections.h>
21
22#if defined(KBUILD_MCOUNT_RA_ADDRESS) && defined(CONFIG_32BIT)
23#define MCOUNT_OFFSET_INSNS 5
24#else
25#define MCOUNT_OFFSET_INSNS 4
26#endif
27
28/*
29 * Check if the address is in kernel space
30 *
31 * Clone core_kernel_text() from kernel/extable.c, but doesn't call
32 * init_kernel_text() for Ftrace doesn't trace functions in init sections.
33 */
34static inline int in_kernel_space(unsigned long ip)
35{
36 if (ip >= (unsigned long)_stext &&
37 ip <= (unsigned long)_etext)
38 return 1;
39 return 0;
40}
41
42#ifdef CONFIG_DYNAMIC_FTRACE
43
44#define JAL 0x0c000000 /* jump & link: ip --> ra, jump to target */
45#define ADDR_MASK 0x03ffffff /* op_code|addr : 31...26|25 ....0 */
46#define JUMP_RANGE_MASK ((1UL << 28) - 1)
47
48#define INSN_NOP 0x00000000 /* nop */
49#define INSN_JAL(addr) \
50 ((unsigned int)(JAL | (((addr) >> 2) & ADDR_MASK)))
51
52static unsigned int insn_jal_ftrace_caller __read_mostly;
53static unsigned int insn_lui_v1_hi16_mcount __read_mostly;
54static unsigned int insn_j_ftrace_graph_caller __maybe_unused __read_mostly;
55
56static inline void ftrace_dyn_arch_init_insns(void)
57{
58 u32 *buf;
59 unsigned int v1;
60
61 /* lui v1, hi16_mcount */
62 v1 = 3;
63 buf = (u32 *)&insn_lui_v1_hi16_mcount;
64 UASM_i_LA_mostly(&buf, v1, MCOUNT_ADDR);
65
66 /* jal (ftrace_caller + 8), jump over the first two instruction */
67 buf = (u32 *)&insn_jal_ftrace_caller;
68 uasm_i_jal(&buf, (FTRACE_ADDR + 8) & JUMP_RANGE_MASK);
69
70#ifdef CONFIG_FUNCTION_GRAPH_TRACER
71 /* j ftrace_graph_caller */
72 buf = (u32 *)&insn_j_ftrace_graph_caller;
73 uasm_i_j(&buf, (unsigned long)ftrace_graph_caller & JUMP_RANGE_MASK);
74#endif
75}
76
77static int ftrace_modify_code(unsigned long ip, unsigned int new_code)
78{
79 int faulted;
80
81 /* *(unsigned int *)ip = new_code; */
82 safe_store_code(new_code, ip, faulted);
83
84 if (unlikely(faulted))
85 return -EFAULT;
86
87 flush_icache_range(ip, ip + 8);
88
89 return 0;
90}
91
92/*
93 * The details about the calling site of mcount on MIPS
94 *
95 * 1. For kernel:
96 *
97 * move at, ra
98 * jal _mcount --> nop
99 *
100 * 2. For modules:
101 *
102 * 2.1 For KBUILD_MCOUNT_RA_ADDRESS and CONFIG_32BIT
103 *
104 * lui v1, hi_16bit_of_mcount --> b 1f (0x10000005)
105 * addiu v1, v1, low_16bit_of_mcount
106 * move at, ra
107 * move $12, ra_address
108 * jalr v1
109 * sub sp, sp, 8
110 * 1: offset = 5 instructions
111 * 2.2 For the Other situations
112 *
113 * lui v1, hi_16bit_of_mcount --> b 1f (0x10000004)
114 * addiu v1, v1, low_16bit_of_mcount
115 * move at, ra
116 * jalr v1
117 * nop | move $12, ra_address | sub sp, sp, 8
118 * 1: offset = 4 instructions
119 */
120
121#define INSN_B_1F (0x10000000 | MCOUNT_OFFSET_INSNS)
122
123int ftrace_make_nop(struct module *mod,
124 struct dyn_ftrace *rec, unsigned long addr)
125{
126 unsigned int new;
127 unsigned long ip = rec->ip;
128
129 /*
130 * If ip is in kernel space, no long call, otherwise, long call is
131 * needed.
132 */
133 new = in_kernel_space(ip) ? INSN_NOP : INSN_B_1F;
134
135 return ftrace_modify_code(ip, new);
136}
137
138int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
139{
140 unsigned int new;
141 unsigned long ip = rec->ip;
142
143 new = in_kernel_space(ip) ? insn_jal_ftrace_caller :
144 insn_lui_v1_hi16_mcount;
145
146 return ftrace_modify_code(ip, new);
147}
148
149#define FTRACE_CALL_IP ((unsigned long)(&ftrace_call))
150
151int ftrace_update_ftrace_func(ftrace_func_t func)
152{
153 unsigned int new;
154
155 new = INSN_JAL((unsigned long)func);
156
157 return ftrace_modify_code(FTRACE_CALL_IP, new);
158}
159
160int __init ftrace_dyn_arch_init(void *data)
161{
162 /* Encode the instructions when booting */
163 ftrace_dyn_arch_init_insns();
164
165 /* Remove "b ftrace_stub" to ensure ftrace_caller() is executed */
166 ftrace_modify_code(MCOUNT_ADDR, INSN_NOP);
167
168 /* The return code is retured via data */
169 *(unsigned long *)data = 0;
170
171 return 0;
172}
173#endif /* CONFIG_DYNAMIC_FTRACE */
174
175#ifdef CONFIG_FUNCTION_GRAPH_TRACER
176
177#ifdef CONFIG_DYNAMIC_FTRACE
178
179extern void ftrace_graph_call(void);
180#define FTRACE_GRAPH_CALL_IP ((unsigned long)(&ftrace_graph_call))
181
182int ftrace_enable_ftrace_graph_caller(void)
183{
184 return ftrace_modify_code(FTRACE_GRAPH_CALL_IP,
185 insn_j_ftrace_graph_caller);
186}
187
188int ftrace_disable_ftrace_graph_caller(void)
189{
190 return ftrace_modify_code(FTRACE_GRAPH_CALL_IP, INSN_NOP);
191}
192
193#endif /* CONFIG_DYNAMIC_FTRACE */
194
195#ifndef KBUILD_MCOUNT_RA_ADDRESS
196
197#define S_RA_SP (0xafbf << 16) /* s{d,w} ra, offset(sp) */
198#define S_R_SP (0xafb0 << 16) /* s{d,w} R, offset(sp) */
199#define OFFSET_MASK 0xffff /* stack offset range: 0 ~ PT_SIZE */
200
201unsigned long ftrace_get_parent_ra_addr(unsigned long self_ra, unsigned long
202 old_parent_ra, unsigned long parent_ra_addr, unsigned long fp)
203{
204 unsigned long sp, ip, tmp;
205 unsigned int code;
206 int faulted;
207
208 /*
209 * For module, move the ip from the return address after the
210 * instruction "lui v1, hi_16bit_of_mcount"(offset is 24), but for
211 * kernel, move after the instruction "move ra, at"(offset is 16)
212 */
213 ip = self_ra - (in_kernel_space(self_ra) ? 16 : 24);
214
215 /*
216 * search the text until finding the non-store instruction or "s{d,w}
217 * ra, offset(sp)" instruction
218 */
219 do {
220 /* get the code at "ip": code = *(unsigned int *)ip; */
221 safe_load_code(code, ip, faulted);
222
223 if (unlikely(faulted))
224 return 0;
225 /*
226 * If we hit the non-store instruction before finding where the
227 * ra is stored, then this is a leaf function and it does not
228 * store the ra on the stack
229 */
230 if ((code & S_R_SP) != S_R_SP)
231 return parent_ra_addr;
232
233 /* Move to the next instruction */
234 ip -= 4;
235 } while ((code & S_RA_SP) != S_RA_SP);
236
237 sp = fp + (code & OFFSET_MASK);
238
239 /* tmp = *(unsigned long *)sp; */
240 safe_load_stack(tmp, sp, faulted);
241 if (unlikely(faulted))
242 return 0;
243
244 if (tmp == old_parent_ra)
245 return sp;
246 return 0;
247}
248
249#endif /* !KBUILD_MCOUNT_RA_ADDRESS */
250
251/*
252 * Hook the return address and push it in the stack of return addrs
253 * in current thread info.
254 */
255void prepare_ftrace_return(unsigned long *parent_ra_addr, unsigned long self_ra,
256 unsigned long fp)
257{
258 unsigned long old_parent_ra;
259 struct ftrace_graph_ent trace;
260 unsigned long return_hooker = (unsigned long)
261 &return_to_handler;
262 int faulted, insns;
263
264 if (unlikely(atomic_read(¤t->tracing_graph_pause)))
265 return;
266
267 /*
268 * "parent_ra_addr" is the stack address saved the return address of
269 * the caller of _mcount.
270 *
271 * if the gcc < 4.5, a leaf function does not save the return address
272 * in the stack address, so, we "emulate" one in _mcount's stack space,
273 * and hijack it directly, but for a non-leaf function, it save the
274 * return address to the its own stack space, we can not hijack it
275 * directly, but need to find the real stack address,
276 * ftrace_get_parent_addr() does it!
277 *
278 * if gcc>= 4.5, with the new -mmcount-ra-address option, for a
279 * non-leaf function, the location of the return address will be saved
280 * to $12 for us, and for a leaf function, only put a zero into $12. we
281 * do it in ftrace_graph_caller of mcount.S.
282 */
283
284 /* old_parent_ra = *parent_ra_addr; */
285 safe_load_stack(old_parent_ra, parent_ra_addr, faulted);
286 if (unlikely(faulted))
287 goto out;
288#ifndef KBUILD_MCOUNT_RA_ADDRESS
289 parent_ra_addr = (unsigned long *)ftrace_get_parent_ra_addr(self_ra,
290 old_parent_ra, (unsigned long)parent_ra_addr, fp);
291 /*
292 * If fails when getting the stack address of the non-leaf function's
293 * ra, stop function graph tracer and return
294 */
295 if (parent_ra_addr == 0)
296 goto out;
297#endif
298 /* *parent_ra_addr = return_hooker; */
299 safe_store_stack(return_hooker, parent_ra_addr, faulted);
300 if (unlikely(faulted))
301 goto out;
302
303 if (ftrace_push_return_trace(old_parent_ra, self_ra, &trace.depth, fp)
304 == -EBUSY) {
305 *parent_ra_addr = old_parent_ra;
306 return;
307 }
308
309 /*
310 * Get the recorded ip of the current mcount calling site in the
311 * __mcount_loc section, which will be used to filter the function
312 * entries configured through the tracing/set_graph_function interface.
313 */
314
315 insns = in_kernel_space(self_ra) ? 2 : MCOUNT_OFFSET_INSNS + 1;
316 trace.func = self_ra - (MCOUNT_INSN_SIZE * insns);
317
318 /* Only trace if the calling function expects to */
319 if (!ftrace_graph_entry(&trace)) {
320 current->curr_ret_stack--;
321 *parent_ra_addr = old_parent_ra;
322 }
323 return;
324out:
325 ftrace_graph_stop();
326 WARN_ON(1);
327}
328#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
1/*
2 * Code for replacing ftrace calls with jumps.
3 *
4 * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com>
5 * Copyright (C) 2009, 2010 DSLab, Lanzhou University, China
6 * Author: Wu Zhangjin <wuzhangjin@gmail.com>
7 *
8 * Thanks goes to Steven Rostedt for writing the original x86 version.
9 */
10
11#include <linux/uaccess.h>
12#include <linux/init.h>
13#include <linux/ftrace.h>
14#include <linux/syscalls.h>
15
16#include <asm/asm.h>
17#include <asm/asm-offsets.h>
18#include <asm/cacheflush.h>
19#include <asm/syscall.h>
20#include <asm/uasm.h>
21#include <asm/unistd.h>
22
23#include <asm-generic/sections.h>
24
25#if defined(KBUILD_MCOUNT_RA_ADDRESS) && defined(CONFIG_32BIT)
26#define MCOUNT_OFFSET_INSNS 5
27#else
28#define MCOUNT_OFFSET_INSNS 4
29#endif
30
31#ifdef CONFIG_DYNAMIC_FTRACE
32
33/* Arch override because MIPS doesn't need to run this from stop_machine() */
34void arch_ftrace_update_code(int command)
35{
36 ftrace_modify_all_code(command);
37}
38
39#endif
40
41/*
42 * Check if the address is in kernel space
43 *
44 * Clone core_kernel_text() from kernel/extable.c, but doesn't call
45 * init_kernel_text() for Ftrace doesn't trace functions in init sections.
46 */
47static inline int in_kernel_space(unsigned long ip)
48{
49 if (ip >= (unsigned long)_stext &&
50 ip <= (unsigned long)_etext)
51 return 1;
52 return 0;
53}
54
55#ifdef CONFIG_DYNAMIC_FTRACE
56
57#define JAL 0x0c000000 /* jump & link: ip --> ra, jump to target */
58#define ADDR_MASK 0x03ffffff /* op_code|addr : 31...26|25 ....0 */
59#define JUMP_RANGE_MASK ((1UL << 28) - 1)
60
61#define INSN_NOP 0x00000000 /* nop */
62#define INSN_JAL(addr) \
63 ((unsigned int)(JAL | (((addr) >> 2) & ADDR_MASK)))
64
65static unsigned int insn_jal_ftrace_caller __read_mostly;
66static unsigned int insn_lui_v1_hi16_mcount __read_mostly;
67static unsigned int insn_j_ftrace_graph_caller __maybe_unused __read_mostly;
68
69static inline void ftrace_dyn_arch_init_insns(void)
70{
71 u32 *buf;
72 unsigned int v1;
73
74 /* lui v1, hi16_mcount */
75 v1 = 3;
76 buf = (u32 *)&insn_lui_v1_hi16_mcount;
77 UASM_i_LA_mostly(&buf, v1, MCOUNT_ADDR);
78
79 /* jal (ftrace_caller + 8), jump over the first two instruction */
80 buf = (u32 *)&insn_jal_ftrace_caller;
81 uasm_i_jal(&buf, (FTRACE_ADDR + 8) & JUMP_RANGE_MASK);
82
83#ifdef CONFIG_FUNCTION_GRAPH_TRACER
84 /* j ftrace_graph_caller */
85 buf = (u32 *)&insn_j_ftrace_graph_caller;
86 uasm_i_j(&buf, (unsigned long)ftrace_graph_caller & JUMP_RANGE_MASK);
87#endif
88}
89
90static int ftrace_modify_code(unsigned long ip, unsigned int new_code)
91{
92 int faulted;
93 mm_segment_t old_fs;
94
95 /* *(unsigned int *)ip = new_code; */
96 safe_store_code(new_code, ip, faulted);
97
98 if (unlikely(faulted))
99 return -EFAULT;
100
101 old_fs = get_fs();
102 set_fs(get_ds());
103 flush_icache_range(ip, ip + 8);
104 set_fs(old_fs);
105
106 return 0;
107}
108
109#ifndef CONFIG_64BIT
110static int ftrace_modify_code_2(unsigned long ip, unsigned int new_code1,
111 unsigned int new_code2)
112{
113 int faulted;
114
115 safe_store_code(new_code1, ip, faulted);
116 if (unlikely(faulted))
117 return -EFAULT;
118 safe_store_code(new_code2, ip + 4, faulted);
119 if (unlikely(faulted))
120 return -EFAULT;
121 flush_icache_range(ip, ip + 8);
122 return 0;
123}
124#endif
125
126/*
127 * The details about the calling site of mcount on MIPS
128 *
129 * 1. For kernel:
130 *
131 * move at, ra
132 * jal _mcount --> nop
133 *
134 * 2. For modules:
135 *
136 * 2.1 For KBUILD_MCOUNT_RA_ADDRESS and CONFIG_32BIT
137 *
138 * lui v1, hi_16bit_of_mcount --> b 1f (0x10000005)
139 * addiu v1, v1, low_16bit_of_mcount
140 * move at, ra
141 * move $12, ra_address
142 * jalr v1
143 * sub sp, sp, 8
144 * 1: offset = 5 instructions
145 * 2.2 For the Other situations
146 *
147 * lui v1, hi_16bit_of_mcount --> b 1f (0x10000004)
148 * addiu v1, v1, low_16bit_of_mcount
149 * move at, ra
150 * jalr v1
151 * nop | move $12, ra_address | sub sp, sp, 8
152 * 1: offset = 4 instructions
153 */
154
155#define INSN_B_1F (0x10000000 | MCOUNT_OFFSET_INSNS)
156
157int ftrace_make_nop(struct module *mod,
158 struct dyn_ftrace *rec, unsigned long addr)
159{
160 unsigned int new;
161 unsigned long ip = rec->ip;
162
163 /*
164 * If ip is in kernel space, no long call, otherwise, long call is
165 * needed.
166 */
167 new = in_kernel_space(ip) ? INSN_NOP : INSN_B_1F;
168#ifdef CONFIG_64BIT
169 return ftrace_modify_code(ip, new);
170#else
171 /*
172 * On 32 bit MIPS platforms, gcc adds a stack adjust
173 * instruction in the delay slot after the branch to
174 * mcount and expects mcount to restore the sp on return.
175 * This is based on a legacy API and does nothing but
176 * waste instructions so it's being removed at runtime.
177 */
178 return ftrace_modify_code_2(ip, new, INSN_NOP);
179#endif
180}
181
182int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
183{
184 unsigned int new;
185 unsigned long ip = rec->ip;
186
187 new = in_kernel_space(ip) ? insn_jal_ftrace_caller :
188 insn_lui_v1_hi16_mcount;
189
190 return ftrace_modify_code(ip, new);
191}
192
193#define FTRACE_CALL_IP ((unsigned long)(&ftrace_call))
194
195int ftrace_update_ftrace_func(ftrace_func_t func)
196{
197 unsigned int new;
198
199 new = INSN_JAL((unsigned long)func);
200
201 return ftrace_modify_code(FTRACE_CALL_IP, new);
202}
203
204int __init ftrace_dyn_arch_init(void)
205{
206 /* Encode the instructions when booting */
207 ftrace_dyn_arch_init_insns();
208
209 /* Remove "b ftrace_stub" to ensure ftrace_caller() is executed */
210 ftrace_modify_code(MCOUNT_ADDR, INSN_NOP);
211
212 return 0;
213}
214#endif /* CONFIG_DYNAMIC_FTRACE */
215
216#ifdef CONFIG_FUNCTION_GRAPH_TRACER
217
218#ifdef CONFIG_DYNAMIC_FTRACE
219
220extern void ftrace_graph_call(void);
221#define FTRACE_GRAPH_CALL_IP ((unsigned long)(&ftrace_graph_call))
222
223int ftrace_enable_ftrace_graph_caller(void)
224{
225 return ftrace_modify_code(FTRACE_GRAPH_CALL_IP,
226 insn_j_ftrace_graph_caller);
227}
228
229int ftrace_disable_ftrace_graph_caller(void)
230{
231 return ftrace_modify_code(FTRACE_GRAPH_CALL_IP, INSN_NOP);
232}
233
234#endif /* CONFIG_DYNAMIC_FTRACE */
235
236#ifndef KBUILD_MCOUNT_RA_ADDRESS
237
238#define S_RA_SP (0xafbf << 16) /* s{d,w} ra, offset(sp) */
239#define S_R_SP (0xafb0 << 16) /* s{d,w} R, offset(sp) */
240#define OFFSET_MASK 0xffff /* stack offset range: 0 ~ PT_SIZE */
241
242unsigned long ftrace_get_parent_ra_addr(unsigned long self_ra, unsigned long
243 old_parent_ra, unsigned long parent_ra_addr, unsigned long fp)
244{
245 unsigned long sp, ip, tmp;
246 unsigned int code;
247 int faulted;
248
249 /*
250 * For module, move the ip from the return address after the
251 * instruction "lui v1, hi_16bit_of_mcount"(offset is 24), but for
252 * kernel, move after the instruction "move ra, at"(offset is 16)
253 */
254 ip = self_ra - (in_kernel_space(self_ra) ? 16 : 24);
255
256 /*
257 * search the text until finding the non-store instruction or "s{d,w}
258 * ra, offset(sp)" instruction
259 */
260 do {
261 /* get the code at "ip": code = *(unsigned int *)ip; */
262 safe_load_code(code, ip, faulted);
263
264 if (unlikely(faulted))
265 return 0;
266 /*
267 * If we hit the non-store instruction before finding where the
268 * ra is stored, then this is a leaf function and it does not
269 * store the ra on the stack
270 */
271 if ((code & S_R_SP) != S_R_SP)
272 return parent_ra_addr;
273
274 /* Move to the next instruction */
275 ip -= 4;
276 } while ((code & S_RA_SP) != S_RA_SP);
277
278 sp = fp + (code & OFFSET_MASK);
279
280 /* tmp = *(unsigned long *)sp; */
281 safe_load_stack(tmp, sp, faulted);
282 if (unlikely(faulted))
283 return 0;
284
285 if (tmp == old_parent_ra)
286 return sp;
287 return 0;
288}
289
290#endif /* !KBUILD_MCOUNT_RA_ADDRESS */
291
292/*
293 * Hook the return address and push it in the stack of return addrs
294 * in current thread info.
295 */
296void prepare_ftrace_return(unsigned long *parent_ra_addr, unsigned long self_ra,
297 unsigned long fp)
298{
299 unsigned long old_parent_ra;
300 struct ftrace_graph_ent trace;
301 unsigned long return_hooker = (unsigned long)
302 &return_to_handler;
303 int faulted, insns;
304
305 if (unlikely(atomic_read(¤t->tracing_graph_pause)))
306 return;
307
308 /*
309 * "parent_ra_addr" is the stack address saved the return address of
310 * the caller of _mcount.
311 *
312 * if the gcc < 4.5, a leaf function does not save the return address
313 * in the stack address, so, we "emulate" one in _mcount's stack space,
314 * and hijack it directly, but for a non-leaf function, it save the
315 * return address to the its own stack space, we can not hijack it
316 * directly, but need to find the real stack address,
317 * ftrace_get_parent_addr() does it!
318 *
319 * if gcc>= 4.5, with the new -mmcount-ra-address option, for a
320 * non-leaf function, the location of the return address will be saved
321 * to $12 for us, and for a leaf function, only put a zero into $12. we
322 * do it in ftrace_graph_caller of mcount.S.
323 */
324
325 /* old_parent_ra = *parent_ra_addr; */
326 safe_load_stack(old_parent_ra, parent_ra_addr, faulted);
327 if (unlikely(faulted))
328 goto out;
329#ifndef KBUILD_MCOUNT_RA_ADDRESS
330 parent_ra_addr = (unsigned long *)ftrace_get_parent_ra_addr(self_ra,
331 old_parent_ra, (unsigned long)parent_ra_addr, fp);
332 /*
333 * If fails when getting the stack address of the non-leaf function's
334 * ra, stop function graph tracer and return
335 */
336 if (parent_ra_addr == 0)
337 goto out;
338#endif
339 /* *parent_ra_addr = return_hooker; */
340 safe_store_stack(return_hooker, parent_ra_addr, faulted);
341 if (unlikely(faulted))
342 goto out;
343
344 if (ftrace_push_return_trace(old_parent_ra, self_ra, &trace.depth, fp)
345 == -EBUSY) {
346 *parent_ra_addr = old_parent_ra;
347 return;
348 }
349
350 /*
351 * Get the recorded ip of the current mcount calling site in the
352 * __mcount_loc section, which will be used to filter the function
353 * entries configured through the tracing/set_graph_function interface.
354 */
355
356 insns = in_kernel_space(self_ra) ? 2 : MCOUNT_OFFSET_INSNS + 1;
357 trace.func = self_ra - (MCOUNT_INSN_SIZE * insns);
358
359 /* Only trace if the calling function expects to */
360 if (!ftrace_graph_entry(&trace)) {
361 current->curr_ret_stack--;
362 *parent_ra_addr = old_parent_ra;
363 }
364 return;
365out:
366 ftrace_graph_stop();
367 WARN_ON(1);
368}
369#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
370
371#ifdef CONFIG_FTRACE_SYSCALLS
372
373#ifdef CONFIG_32BIT
374unsigned long __init arch_syscall_addr(int nr)
375{
376 return (unsigned long)sys_call_table[nr - __NR_O32_Linux];
377}
378#endif
379
380#ifdef CONFIG_64BIT
381
382unsigned long __init arch_syscall_addr(int nr)
383{
384#ifdef CONFIG_MIPS32_N32
385 if (nr >= __NR_N32_Linux && nr <= __NR_N32_Linux + __NR_N32_Linux_syscalls)
386 return (unsigned long)sysn32_call_table[nr - __NR_N32_Linux];
387#endif
388 if (nr >= __NR_64_Linux && nr <= __NR_64_Linux + __NR_64_Linux_syscalls)
389 return (unsigned long)sys_call_table[nr - __NR_64_Linux];
390#ifdef CONFIG_MIPS32_O32
391 if (nr >= __NR_O32_Linux && nr <= __NR_O32_Linux + __NR_O32_Linux_syscalls)
392 return (unsigned long)sys32_call_table[nr - __NR_O32_Linux];
393#endif
394
395 return (unsigned long) &sys_ni_syscall;
396}
397#endif
398
399#endif /* CONFIG_FTRACE_SYSCALLS */