1 // SPDX-License-Identifier: GPL-2.0
3 * Code for replacing ftrace calls with jumps.
5 * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com>
7 * Thanks goes out to P.A. Semi, Inc for supplying me with a PPC64 box.
9 * Added function graph tracer code, taken from x86 that was written
10 * by Frederic Weisbecker, and ported to PPC by Steven Rostedt.
14 #define pr_fmt(fmt) "ftrace-powerpc: " fmt
16 #include <linux/spinlock.h>
17 #include <linux/hardirq.h>
18 #include <linux/uaccess.h>
19 #include <linux/module.h>
20 #include <linux/ftrace.h>
21 #include <linux/percpu.h>
22 #include <linux/init.h>
23 #include <linux/list.h>
25 #include <asm/asm-prototypes.h>
26 #include <asm/cacheflush.h>
27 #include <asm/code-patching.h>
28 #include <asm/ftrace.h>
29 #include <asm/syscall.h>
33 #ifdef CONFIG_DYNAMIC_FTRACE
36 * We generally only have a single long_branch tramp and at most 2 or 3 plt
37 * tramps generated. But, we don't use the plt tramps currently. We also allot
38 * 2 tramps after .text and .init.text. So, we only end up with around 3 usable
39 * tramps in total. Set aside 8 just to be sure.
41 #define NUM_FTRACE_TRAMPS 8
42 static unsigned long ftrace_tramps[NUM_FTRACE_TRAMPS];
44 static struct ppc_inst
45 ftrace_call_replace(unsigned long ip, unsigned long addr, int link)
49 addr = ppc_function_entry((void *)addr);
51 /* if (link) set op to 'bl' else 'b' */
52 create_branch(&op, (struct ppc_inst *)ip, addr, link ? 1 : 0);
58 ftrace_modify_code(unsigned long ip, struct ppc_inst old, struct ppc_inst new)
60 struct ppc_inst replaced;
64 * We are paranoid about modifying text, as if a bug was to happen, it
65 * could cause us to read or write to someplace that could cause harm.
66 * Carefully read and modify the code with probe_kernel_*(), and make
67 * sure what we read is what we expected it to be before modifying it.
70 /* read the text we want to modify */
71 if (probe_kernel_read_inst(&replaced, (void *)ip))
74 /* Make sure it is what we expect it to be */
75 if (!ppc_inst_equal(replaced, old)) {
76 pr_err("%p: replaced (%#x) != old (%#x)",
77 (void *)ip, ppc_inst_val(replaced), ppc_inst_val(old));
81 /* replace the text with the new text */
82 if (patch_instruction((struct ppc_inst *)ip, new))
89 * Helper functions that are the same for both PPC64 and PPC32.
91 static int test_24bit_addr(unsigned long ip, unsigned long addr)
94 addr = ppc_function_entry((void *)addr);
96 /* use the create_branch to verify that this offset can be branched */
97 return create_branch(&op, (struct ppc_inst *)ip, addr, 0) == 0;
100 static int is_bl_op(struct ppc_inst op)
102 return (ppc_inst_val(op) & 0xfc000003) == 0x48000001;
105 static int is_b_op(struct ppc_inst op)
107 return (ppc_inst_val(op) & 0xfc000003) == 0x48000000;
110 static unsigned long find_bl_target(unsigned long ip, struct ppc_inst op)
114 offset = (ppc_inst_val(op) & 0x03fffffc);
116 if (offset & 0x02000000)
117 offset |= 0xfe000000;
119 return ip + (long)offset;
122 #ifdef CONFIG_MODULES
125 __ftrace_make_nop(struct module *mod,
126 struct dyn_ftrace *rec, unsigned long addr)
128 unsigned long entry, ptr, tramp;
129 unsigned long ip = rec->ip;
130 struct ppc_inst op, pop;
132 /* read where this goes */
133 if (probe_kernel_read_inst(&op, (void *)ip)) {
134 pr_err("Fetching opcode failed.\n");
138 /* Make sure that that this is still a 24bit jump */
140 pr_err("Not expected bl: opcode is %x\n", ppc_inst_val(op));
144 /* lets find where the pointer goes */
145 tramp = find_bl_target(ip, op);
147 pr_devel("ip:%lx jumps to %lx", ip, tramp);
149 if (module_trampoline_target(mod, tramp, &ptr)) {
150 pr_err("Failed to get trampoline target\n");
154 pr_devel("trampoline target %lx", ptr);
156 entry = ppc_global_function_entry((void *)addr);
157 /* This should match what was called */
159 pr_err("addr %lx does not match expected %lx\n", ptr, entry);
163 #ifdef CONFIG_MPROFILE_KERNEL
164 /* When using -mkernel_profile there is no load to jump over */
165 pop = ppc_inst(PPC_INST_NOP);
167 if (probe_kernel_read_inst(&op, (void *)(ip - 4))) {
168 pr_err("Fetching instruction at %lx failed.\n", ip - 4);
172 /* We expect either a mflr r0, or a std r0, LRSAVE(r1) */
173 if (!ppc_inst_equal(op, ppc_inst(PPC_INST_MFLR)) &&
174 !ppc_inst_equal(op, ppc_inst(PPC_INST_STD_LR))) {
175 pr_err("Unexpected instruction %08x around bl _mcount\n",
181 * Our original call site looks like:
186 * Milton Miller pointed out that we can not simply nop the branch.
187 * If a task was preempted when calling a trace function, the nops
188 * will remove the way to restore the TOC in r2 and the r2 TOC will
191 * Use a b +8 to jump over the load.
194 pop = ppc_inst(PPC_INST_BRANCH | 8); /* b +8 */
197 * Check what is in the next instruction. We can see ld r2,40(r1), but
198 * on first pass after boot we will see mflr r0.
200 if (probe_kernel_read_inst(&op, (void *)(ip + 4))) {
201 pr_err("Fetching op failed.\n");
205 if (!ppc_inst_equal(op, ppc_inst(PPC_INST_LD_TOC))) {
206 pr_err("Expected %08x found %08x\n", PPC_INST_LD_TOC, ppc_inst_val(op));
209 #endif /* CONFIG_MPROFILE_KERNEL */
211 if (patch_instruction((struct ppc_inst *)ip, pop)) {
212 pr_err("Patching NOP failed.\n");
221 __ftrace_make_nop(struct module *mod,
222 struct dyn_ftrace *rec, unsigned long addr)
226 unsigned long ip = rec->ip;
229 if (copy_from_kernel_nofault(&op, (void *)ip, MCOUNT_INSN_SIZE))
232 /* Make sure that that this is still a 24bit jump */
234 pr_err("Not expected bl: opcode is %x\n", ppc_inst_val(op));
238 /* lets find where the pointer goes */
239 tramp = find_bl_target(ip, op);
242 * On PPC32 the trampoline looks like:
243 * 0x3d, 0x80, 0x00, 0x00 lis r12,sym@ha
244 * 0x39, 0x8c, 0x00, 0x00 addi r12,r12,sym@l
245 * 0x7d, 0x89, 0x03, 0xa6 mtctr r12
246 * 0x4e, 0x80, 0x04, 0x20 bctr
249 pr_devel("ip:%lx jumps to %lx", ip, tramp);
251 /* Find where the trampoline jumps to */
252 if (copy_from_kernel_nofault(jmp, (void *)tramp, sizeof(jmp))) {
253 pr_err("Failed to read %lx\n", tramp);
257 pr_devel(" %08x %08x ", jmp[0], jmp[1]);
259 /* verify that this is what we expect it to be */
260 if (((jmp[0] & 0xffff0000) != 0x3d800000) ||
261 ((jmp[1] & 0xffff0000) != 0x398c0000) ||
262 (jmp[2] != 0x7d8903a6) ||
263 (jmp[3] != 0x4e800420)) {
264 pr_err("Not a trampoline\n");
268 tramp = (jmp[1] & 0xffff) |
269 ((jmp[0] & 0xffff) << 16);
273 pr_devel(" %lx ", tramp);
276 pr_err("Trampoline location %08lx does not match addr\n",
281 op = ppc_inst(PPC_INST_NOP);
283 if (patch_instruction((struct ppc_inst *)ip, op))
289 #endif /* CONFIG_MODULES */
291 static unsigned long find_ftrace_tramp(unsigned long ip)
294 struct ppc_inst instr;
297 * We have the compiler generated long_branch tramps at the end
298 * and we prefer those
300 for (i = NUM_FTRACE_TRAMPS - 1; i >= 0; i--)
301 if (!ftrace_tramps[i])
303 else if (create_branch(&instr, (void *)ip,
304 ftrace_tramps[i], 0) == 0)
305 return ftrace_tramps[i];
310 static int add_ftrace_tramp(unsigned long tramp)
314 for (i = 0; i < NUM_FTRACE_TRAMPS; i++)
315 if (!ftrace_tramps[i]) {
316 ftrace_tramps[i] = tramp;
324 * If this is a compiler generated long_branch trampoline (essentially, a
325 * trampoline that has a branch to _mcount()), we re-write the branch to
326 * instead go to ftrace_[regs_]caller() and note down the location of this
329 static int setup_mcount_compiler_tramp(unsigned long tramp)
334 struct ppc_inst instr;
335 static unsigned long ftrace_plt_tramps[NUM_FTRACE_TRAMPS];
337 /* Is this a known long jump tramp? */
338 for (i = 0; i < NUM_FTRACE_TRAMPS; i++)
339 if (!ftrace_tramps[i])
341 else if (ftrace_tramps[i] == tramp)
344 /* Is this a known plt tramp? */
345 for (i = 0; i < NUM_FTRACE_TRAMPS; i++)
346 if (!ftrace_plt_tramps[i])
348 else if (ftrace_plt_tramps[i] == tramp)
351 /* New trampoline -- read where this goes */
352 if (probe_kernel_read_inst(&op, (void *)tramp)) {
353 pr_debug("Fetching opcode failed.\n");
357 /* Is this a 24 bit branch? */
359 pr_debug("Trampoline is not a long branch tramp.\n");
363 /* lets find where the pointer goes */
364 ptr = find_bl_target(tramp, op);
366 if (ptr != ppc_global_function_entry((void *)_mcount)) {
367 pr_debug("Trampoline target %p is not _mcount\n", (void *)ptr);
371 /* Let's re-write the tramp to go to ftrace_[regs_]caller */
372 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
373 ptr = ppc_global_function_entry((void *)ftrace_regs_caller);
375 ptr = ppc_global_function_entry((void *)ftrace_caller);
377 if (create_branch(&instr, (void *)tramp, ptr, 0)) {
378 pr_debug("%ps is not reachable from existing mcount tramp\n",
383 if (patch_branch((struct ppc_inst *)tramp, ptr, 0)) {
384 pr_debug("REL24 out of range!\n");
388 if (add_ftrace_tramp(tramp)) {
389 pr_debug("No tramp locations left\n");
396 static int __ftrace_make_nop_kernel(struct dyn_ftrace *rec, unsigned long addr)
398 unsigned long tramp, ip = rec->ip;
401 /* Read where this goes */
402 if (probe_kernel_read_inst(&op, (void *)ip)) {
403 pr_err("Fetching opcode failed.\n");
407 /* Make sure that that this is still a 24bit jump */
409 pr_err("Not expected bl: opcode is %x\n", ppc_inst_val(op));
413 /* Let's find where the pointer goes */
414 tramp = find_bl_target(ip, op);
416 pr_devel("ip:%lx jumps to %lx", ip, tramp);
418 if (setup_mcount_compiler_tramp(tramp)) {
419 /* Are other trampolines reachable? */
420 if (!find_ftrace_tramp(ip)) {
421 pr_err("No ftrace trampolines reachable from %ps\n",
427 if (patch_instruction((struct ppc_inst *)ip, ppc_inst(PPC_INST_NOP))) {
428 pr_err("Patching NOP failed.\n");
435 int ftrace_make_nop(struct module *mod,
436 struct dyn_ftrace *rec, unsigned long addr)
438 unsigned long ip = rec->ip;
439 struct ppc_inst old, new;
442 * If the calling address is more that 24 bits away,
443 * then we had to use a trampoline to make the call.
444 * Otherwise just update the call site.
446 if (test_24bit_addr(ip, addr)) {
448 old = ftrace_call_replace(ip, addr, 1);
449 new = ppc_inst(PPC_INST_NOP);
450 return ftrace_modify_code(ip, old, new);
451 } else if (core_kernel_text(ip))
452 return __ftrace_make_nop_kernel(rec, addr);
454 #ifdef CONFIG_MODULES
456 * Out of range jumps are called from modules.
457 * We should either already have a pointer to the module
458 * or it has been passed in.
460 if (!rec->arch.mod) {
462 pr_err("No module loaded addr=%lx\n", addr);
467 if (mod != rec->arch.mod) {
468 pr_err("Record mod %p not equal to passed in mod %p\n",
472 /* nothing to do if mod == rec->arch.mod */
476 return __ftrace_make_nop(mod, rec, addr);
478 /* We should not get here without modules */
480 #endif /* CONFIG_MODULES */
483 #ifdef CONFIG_MODULES
486 * Examine the existing instructions for __ftrace_make_call.
487 * They should effectively be a NOP, and follow formal constraints,
488 * depending on the ABI. Return false if they don't.
490 #ifndef CONFIG_MPROFILE_KERNEL
492 expected_nop_sequence(void *ip, struct ppc_inst op0, struct ppc_inst op1)
500 * The load offset is different depending on the ABI. For simplicity
501 * just mask it out when doing the compare.
503 if (!ppc_inst_equal(op0, ppc_inst(0x48000008)) ||
504 (ppc_inst_val(op1) & 0xffff0000) != 0xe8410000)
510 expected_nop_sequence(void *ip, struct ppc_inst op0, struct ppc_inst op1)
512 /* look for patched "NOP" on ppc64 with -mprofile-kernel */
513 if (!ppc_inst_equal(op0, ppc_inst(PPC_INST_NOP)))
520 __ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
522 struct ppc_inst op[2];
523 struct ppc_inst instr;
524 void *ip = (void *)rec->ip;
525 unsigned long entry, ptr, tramp;
526 struct module *mod = rec->arch.mod;
528 /* read where this goes */
529 if (probe_kernel_read_inst(op, ip))
532 if (probe_kernel_read_inst(op + 1, ip + 4))
535 if (!expected_nop_sequence(ip, op[0], op[1])) {
536 pr_err("Unexpected call sequence at %p: %x %x\n",
537 ip, ppc_inst_val(op[0]), ppc_inst_val(op[1]));
541 /* If we never set up ftrace trampoline(s), then bail */
542 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
543 if (!mod->arch.tramp || !mod->arch.tramp_regs) {
545 if (!mod->arch.tramp) {
547 pr_err("No ftrace trampoline\n");
551 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
552 if (rec->flags & FTRACE_FL_REGS)
553 tramp = mod->arch.tramp_regs;
556 tramp = mod->arch.tramp;
558 if (module_trampoline_target(mod, tramp, &ptr)) {
559 pr_err("Failed to get trampoline target\n");
563 pr_devel("trampoline target %lx", ptr);
565 entry = ppc_global_function_entry((void *)addr);
566 /* This should match what was called */
568 pr_err("addr %lx does not match expected %lx\n", ptr, entry);
572 /* Ensure branch is within 24 bits */
573 if (create_branch(&instr, ip, tramp, BRANCH_SET_LINK)) {
574 pr_err("Branch out of range\n");
578 if (patch_branch(ip, tramp, BRANCH_SET_LINK)) {
579 pr_err("REL24 out of range!\n");
586 #else /* !CONFIG_PPC64: */
588 __ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
592 unsigned long ip = rec->ip;
594 /* read where this goes */
595 if (probe_kernel_read_inst(&op, (void *)ip))
598 /* It should be pointing to a nop */
599 if (!ppc_inst_equal(op, ppc_inst(PPC_INST_NOP))) {
600 pr_err("Expected NOP but have %x\n", ppc_inst_val(op));
604 /* If we never set up a trampoline to ftrace_caller, then bail */
605 if (!rec->arch.mod->arch.tramp) {
606 pr_err("No ftrace trampoline\n");
610 /* create the branch to the trampoline */
611 err = create_branch(&op, (struct ppc_inst *)ip,
612 rec->arch.mod->arch.tramp, BRANCH_SET_LINK);
614 pr_err("REL24 out of range!\n");
618 pr_devel("write to %lx\n", rec->ip);
620 if (patch_instruction((struct ppc_inst *)ip, op))
625 #endif /* CONFIG_PPC64 */
626 #endif /* CONFIG_MODULES */
628 static int __ftrace_make_call_kernel(struct dyn_ftrace *rec, unsigned long addr)
631 void *ip = (void *)rec->ip;
632 unsigned long tramp, entry, ptr;
634 /* Make sure we're being asked to patch branch to a known ftrace addr */
635 entry = ppc_global_function_entry((void *)ftrace_caller);
636 ptr = ppc_global_function_entry((void *)addr);
639 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
640 entry = ppc_global_function_entry((void *)ftrace_regs_caller);
643 pr_err("Unknown ftrace addr to patch: %ps\n", (void *)ptr);
645 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
650 /* Make sure we have a nop */
651 if (probe_kernel_read_inst(&op, ip)) {
652 pr_err("Unable to read ftrace location %p\n", ip);
656 if (!ppc_inst_equal(op, ppc_inst(PPC_INST_NOP))) {
657 pr_err("Unexpected call sequence at %p: %x\n", ip, ppc_inst_val(op));
661 tramp = find_ftrace_tramp((unsigned long)ip);
663 pr_err("No ftrace trampolines reachable from %ps\n", ip);
667 if (patch_branch(ip, tramp, BRANCH_SET_LINK)) {
668 pr_err("Error patching branch to ftrace tramp!\n");
675 int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
677 unsigned long ip = rec->ip;
678 struct ppc_inst old, new;
681 * If the calling address is more that 24 bits away,
682 * then we had to use a trampoline to make the call.
683 * Otherwise just update the call site.
685 if (test_24bit_addr(ip, addr)) {
687 old = ppc_inst(PPC_INST_NOP);
688 new = ftrace_call_replace(ip, addr, 1);
689 return ftrace_modify_code(ip, old, new);
690 } else if (core_kernel_text(ip))
691 return __ftrace_make_call_kernel(rec, addr);
693 #ifdef CONFIG_MODULES
695 * Out of range jumps are called from modules.
696 * Being that we are converting from nop, it had better
697 * already have a module defined.
699 if (!rec->arch.mod) {
700 pr_err("No module loaded\n");
704 return __ftrace_make_call(rec, addr);
706 /* We should not get here without modules */
708 #endif /* CONFIG_MODULES */
711 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
712 #ifdef CONFIG_MODULES
714 __ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr,
718 unsigned long ip = rec->ip;
719 unsigned long entry, ptr, tramp;
720 struct module *mod = rec->arch.mod;
722 /* If we never set up ftrace trampolines, then bail */
723 if (!mod->arch.tramp || !mod->arch.tramp_regs) {
724 pr_err("No ftrace trampoline\n");
728 /* read where this goes */
729 if (probe_kernel_read_inst(&op, (void *)ip)) {
730 pr_err("Fetching opcode failed.\n");
734 /* Make sure that that this is still a 24bit jump */
736 pr_err("Not expected bl: opcode is %x\n", ppc_inst_val(op));
740 /* lets find where the pointer goes */
741 tramp = find_bl_target(ip, op);
742 entry = ppc_global_function_entry((void *)old_addr);
744 pr_devel("ip:%lx jumps to %lx", ip, tramp);
746 if (tramp != entry) {
747 /* old_addr is not within range, so we must have used a trampoline */
748 if (module_trampoline_target(mod, tramp, &ptr)) {
749 pr_err("Failed to get trampoline target\n");
753 pr_devel("trampoline target %lx", ptr);
755 /* This should match what was called */
757 pr_err("addr %lx does not match expected %lx\n", ptr, entry);
762 /* The new target may be within range */
763 if (test_24bit_addr(ip, addr)) {
765 if (patch_branch((struct ppc_inst *)ip, addr, BRANCH_SET_LINK)) {
766 pr_err("REL24 out of range!\n");
773 if (rec->flags & FTRACE_FL_REGS)
774 tramp = mod->arch.tramp_regs;
776 tramp = mod->arch.tramp;
778 if (module_trampoline_target(mod, tramp, &ptr)) {
779 pr_err("Failed to get trampoline target\n");
783 pr_devel("trampoline target %lx", ptr);
785 entry = ppc_global_function_entry((void *)addr);
786 /* This should match what was called */
788 pr_err("addr %lx does not match expected %lx\n", ptr, entry);
792 /* Ensure branch is within 24 bits */
793 if (create_branch(&op, (struct ppc_inst *)ip, tramp, BRANCH_SET_LINK)) {
794 pr_err("Branch out of range\n");
798 if (patch_branch((struct ppc_inst *)ip, tramp, BRANCH_SET_LINK)) {
799 pr_err("REL24 out of range!\n");
807 int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr,
810 unsigned long ip = rec->ip;
811 struct ppc_inst old, new;
814 * If the calling address is more that 24 bits away,
815 * then we had to use a trampoline to make the call.
816 * Otherwise just update the call site.
818 if (test_24bit_addr(ip, addr) && test_24bit_addr(ip, old_addr)) {
820 old = ftrace_call_replace(ip, old_addr, 1);
821 new = ftrace_call_replace(ip, addr, 1);
822 return ftrace_modify_code(ip, old, new);
823 } else if (core_kernel_text(ip)) {
825 * We always patch out of range locations to go to the regs
826 * variant, so there is nothing to do here
831 #ifdef CONFIG_MODULES
833 * Out of range jumps are called from modules.
835 if (!rec->arch.mod) {
836 pr_err("No module loaded\n");
840 return __ftrace_modify_call(rec, old_addr, addr);
842 /* We should not get here without modules */
844 #endif /* CONFIG_MODULES */
848 int ftrace_update_ftrace_func(ftrace_func_t func)
850 unsigned long ip = (unsigned long)(&ftrace_call);
851 struct ppc_inst old, new;
854 old = ppc_inst_read((struct ppc_inst *)&ftrace_call);
855 new = ftrace_call_replace(ip, (unsigned long)func, 1);
856 ret = ftrace_modify_code(ip, old, new);
858 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
859 /* Also update the regs callback function */
861 ip = (unsigned long)(&ftrace_regs_call);
862 old = ppc_inst_read((struct ppc_inst *)&ftrace_regs_call);
863 new = ftrace_call_replace(ip, (unsigned long)func, 1);
864 ret = ftrace_modify_code(ip, old, new);
872 * Use the default ftrace_modify_all_code, but without
875 void arch_ftrace_update_code(int command)
877 ftrace_modify_all_code(command);
881 #define PACATOC offsetof(struct paca_struct, kernel_toc)
883 extern unsigned int ftrace_tramp_text[], ftrace_tramp_init[];
885 int __init ftrace_dyn_arch_init(void)
888 unsigned int *tramp[] = { ftrace_tramp_text, ftrace_tramp_init };
890 0xe98d0000 | PACATOC, /* ld r12,PACATOC(r13) */
891 0x3d8c0000, /* addis r12,r12,<high> */
892 0x398c0000, /* addi r12,r12,<low> */
893 0x7d8903a6, /* mtctr r12 */
894 0x4e800420, /* bctr */
896 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
897 unsigned long addr = ppc_global_function_entry((void *)ftrace_regs_caller);
899 unsigned long addr = ppc_global_function_entry((void *)ftrace_caller);
901 long reladdr = addr - kernel_toc_addr();
903 if (reladdr > 0x7FFFFFFF || reladdr < -(0x80000000L)) {
904 pr_err("Address of %ps out of range of kernel_toc.\n",
909 for (i = 0; i < 2; i++) {
910 memcpy(tramp[i], stub_insns, sizeof(stub_insns));
911 tramp[i][1] |= PPC_HA(reladdr);
912 tramp[i][2] |= PPC_LO(reladdr);
913 add_ftrace_tramp((unsigned long)tramp[i]);
919 int __init ftrace_dyn_arch_init(void)
924 #endif /* CONFIG_DYNAMIC_FTRACE */
926 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
928 extern void ftrace_graph_call(void);
929 extern void ftrace_graph_stub(void);
931 int ftrace_enable_ftrace_graph_caller(void)
933 unsigned long ip = (unsigned long)(&ftrace_graph_call);
934 unsigned long addr = (unsigned long)(&ftrace_graph_caller);
935 unsigned long stub = (unsigned long)(&ftrace_graph_stub);
936 struct ppc_inst old, new;
938 old = ftrace_call_replace(ip, stub, 0);
939 new = ftrace_call_replace(ip, addr, 0);
941 return ftrace_modify_code(ip, old, new);
944 int ftrace_disable_ftrace_graph_caller(void)
946 unsigned long ip = (unsigned long)(&ftrace_graph_call);
947 unsigned long addr = (unsigned long)(&ftrace_graph_caller);
948 unsigned long stub = (unsigned long)(&ftrace_graph_stub);
949 struct ppc_inst old, new;
951 old = ftrace_call_replace(ip, addr, 0);
952 new = ftrace_call_replace(ip, stub, 0);
954 return ftrace_modify_code(ip, old, new);
958 * Hook the return address and push it in the stack of return addrs
959 * in current thread info. Return the address we want to divert to.
961 unsigned long prepare_ftrace_return(unsigned long parent, unsigned long ip,
964 unsigned long return_hooker;
966 if (unlikely(ftrace_graph_is_dead()))
969 if (unlikely(atomic_read(¤t->tracing_graph_pause)))
972 return_hooker = ppc_function_entry(return_to_handler);
974 if (!function_graph_enter(parent, ip, 0, (unsigned long *)sp))
975 parent = return_hooker;
979 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
981 #ifdef PPC64_ELF_ABI_v1
982 char *arch_ftrace_match_adjust(char *str, const char *search)
984 if (str[0] == '.' && search[0] != '.')
989 #endif /* PPC64_ELF_ABI_v1 */