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1// SPDX-License-Identifier: GPL-2.0-only2/*3 *4 * Copyright (C) 2015 Naveen N. Rao, IBM Corporation5 */6 7#include "dso.h"8#include "symbol.h"9#include "map.h"10#include "probe-event.h"11#include "probe-file.h"12 13int arch__choose_best_symbol(struct symbol *syma,14 struct symbol *symb __maybe_unused)15{16 char *sym = syma->name;17 18#if !defined(_CALL_ELF) || _CALL_ELF != 219 /* Skip over any initial dot */20 if (*sym == '.')21 sym++;22#endif23 24 /* Avoid "SyS" kernel syscall aliases */25 if (strlen(sym) >= 3 && !strncmp(sym, "SyS", 3))26 return SYMBOL_B;27 if (strlen(sym) >= 10 && !strncmp(sym, "compat_SyS", 10))28 return SYMBOL_B;29 30 return SYMBOL_A;31}32 33#if !defined(_CALL_ELF) || _CALL_ELF != 234/* Allow matching against dot variants */35int arch__compare_symbol_names(const char *namea, const char *nameb)36{37 /* Skip over initial dot */38 if (*namea == '.')39 namea++;40 if (*nameb == '.')41 nameb++;42 43 return strcmp(namea, nameb);44}45 46int arch__compare_symbol_names_n(const char *namea, const char *nameb,47 unsigned int n)48{49 /* Skip over initial dot */50 if (*namea == '.')51 namea++;52 if (*nameb == '.')53 nameb++;54 55 return strncmp(namea, nameb, n);56}57 58const char *arch__normalize_symbol_name(const char *name)59{60 /* Skip over initial dot */61 if (name && *name == '.')62 name++;63 return name;64}65#endif66 67#if defined(_CALL_ELF) && _CALL_ELF == 268 69#ifdef HAVE_LIBELF_SUPPORT70void arch__sym_update(struct symbol *s, GElf_Sym *sym)71{72 s->arch_sym = sym->st_other;73}74#endif75 76#define PPC64LE_LEP_OFFSET 877 78void arch__fix_tev_from_maps(struct perf_probe_event *pev,79 struct probe_trace_event *tev, struct map *map,80 struct symbol *sym)81{82 int lep_offset;83 84 /*85 * When probing at a function entry point, we normally always want the86 * LEP since that catches calls to the function through both the GEP and87 * the LEP. Hence, we would like to probe at an offset of 8 bytes if88 * the user only specified the function entry.89 *90 * However, if the user specifies an offset, we fall back to using the91 * GEP since all userspace applications (objdump/readelf) show function92 * disassembly with offsets from the GEP.93 */94 if (pev->point.offset || !map || !sym)95 return;96 97 /* For kretprobes, add an offset only if the kernel supports it */98 if (!pev->uprobes && pev->point.retprobe) {99#ifdef HAVE_LIBELF_SUPPORT100 if (!kretprobe_offset_is_supported())101#endif102 return;103 }104 105 lep_offset = PPC64_LOCAL_ENTRY_OFFSET(sym->arch_sym);106 107 if (map__dso(map)->symtab_type == DSO_BINARY_TYPE__KALLSYMS)108 tev->point.offset += PPC64LE_LEP_OFFSET;109 else if (lep_offset) {110 if (pev->uprobes)111 tev->point.address += lep_offset;112 else113 tev->point.offset += lep_offset;114 }115}116 117#ifdef HAVE_LIBELF_SUPPORT118void arch__post_process_probe_trace_events(struct perf_probe_event *pev,119 int ntevs)120{121 struct probe_trace_event *tev;122 struct map *map;123 struct symbol *sym = NULL;124 struct rb_node *tmp;125 int i = 0;126 127 map = get_target_map(pev->target, pev->nsi, pev->uprobes);128 if (!map || map__load(map) < 0)129 return;130 131 for (i = 0; i < ntevs; i++) {132 tev = &pev->tevs[i];133 map__for_each_symbol(map, sym, tmp) {134 if (map__unmap_ip(map, sym->start) == tev->point.address) {135 arch__fix_tev_from_maps(pev, tev, map, sym);136 break;137 }138 }139 }140}141#endif /* HAVE_LIBELF_SUPPORT */142 143#endif144