Commit 4e0d1e8b authored by Arnaldo Carvalho de Melo's avatar Arnaldo Carvalho de Melo
Browse files

perf symbols: Split kernel symbol processing from dso__load_sym() 

More should be done to split this function, removing stuff map
relocation steps from the actual symbol table loading.

Arch specific stuff also should go elsewhere, to tools/arch/ and
we should have it keyed by data from the perf_env either in the
perf.data header or from the running environment.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-236gyo6cx6iet90u3uc01cws@git.kernel.org


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent 857140e8

tools/perf/util/symbol-elf.c

+108 −97
Original line number Diff line number Diff line
@@ -797,6 +797,110 @@ static u64 ref_reloc(struct kmap *kmap) 
void __weak arch__sym_update(struct symbol *s __maybe_unused,

		GElf_Sym *sym __maybe_unused) { }



static int dso__process_kernel_symbol(struct dso *dso, struct map *map,

				      GElf_Sym *sym, GElf_Shdr *shdr,

				      struct map_groups *kmaps, struct kmap *kmap,

				      struct dso **curr_dsop, struct map **curr_mapp,

				      const char *section_name,

				      bool adjust_kernel_syms, bool kmodule, bool *remap_kernel)

{

	struct dso *curr_dso = *curr_dsop;

	struct map *curr_map;

	char dso_name[PATH_MAX];



	/* Adjust symbol to map to file offset */

	if (adjust_kernel_syms)

		sym->st_value -= shdr->sh_addr - shdr->sh_offset;



	if (strcmp(section_name, (curr_dso->short_name + dso->short_name_len)) == 0)

		return 0;



	if (strcmp(section_name, ".text") == 0) {

		/*

		 * The initial kernel mapping is based on

		 * kallsyms and identity maps.  Overwrite it to

		 * map to the kernel dso.

		 */

		if (*remap_kernel && dso->kernel) {

			*remap_kernel = false;

			map->start = shdr->sh_addr + ref_reloc(kmap);

			map->end = map->start + shdr->sh_size;

			map->pgoff = shdr->sh_offset;

			map->map_ip = map__map_ip;

			map->unmap_ip = map__unmap_ip;

			/* Ensure maps are correctly ordered */

			if (kmaps) {

				map__get(map);

				map_groups__remove(kmaps, map);

				map_groups__insert(kmaps, map);

				map__put(map);

			}

		}



		/*

		 * The initial module mapping is based on

		 * /proc/modules mapped to offset zero.

		 * Overwrite it to map to the module dso.

		 */

		if (*remap_kernel && kmodule) {

			*remap_kernel = false;

			map->pgoff = shdr->sh_offset;

		}



		*curr_mapp = map;

		*curr_dsop = dso;

		return 0;

	}



	if (!kmap)

		return 0;



	snprintf(dso_name, sizeof(dso_name), "%s%s", dso->short_name, section_name);



	curr_map = map_groups__find_by_name(kmaps, dso_name);

	if (curr_map == NULL) {

		u64 start = sym->st_value;



		if (kmodule)

			start += map->start + shdr->sh_offset;



		curr_dso = dso__new(dso_name);

		if (curr_dso == NULL)

			return -1;

		curr_dso->kernel = dso->kernel;

		curr_dso->long_name = dso->long_name;

		curr_dso->long_name_len = dso->long_name_len;

		curr_map = map__new2(start, curr_dso);

		dso__put(curr_dso);

		if (curr_map == NULL)

			return -1;



		if (adjust_kernel_syms) {

			curr_map->start  = shdr->sh_addr + ref_reloc(kmap);

			curr_map->end	 = curr_map->start + shdr->sh_size;

			curr_map->pgoff	 = shdr->sh_offset;

		} else {

			curr_map->map_ip = curr_map->unmap_ip = identity__map_ip;

		}

		curr_dso->symtab_type = dso->symtab_type;

		map_groups__insert(kmaps, curr_map);

		/*

		 * Add it before we drop the referece to curr_map, i.e. while

		 * we still are sure to have a reference to this DSO via

		 * *curr_map->dso.

		 */

		dsos__add(&map->groups->machine->dsos, curr_dso);

		/* kmaps already got it */

		map__put(curr_map);

		dso__set_loaded(curr_dso);

		*curr_mapp = curr_map;

		*curr_dsop = curr_dso;

	} else

		*curr_dsop = curr_map->dso;



	return 0;

}



int dso__load_sym(struct dso *dso, struct map *map, struct symsrc *syms_ss,

		  struct symsrc *runtime_ss, int kmodule)

{
@@ -973,102 +1077,9 @@ int dso__load_sym(struct dso *dso, struct map *map, struct symsrc *syms_ss, 
			--sym.st_value;



		if (dso->kernel || kmodule) {

			char dso_name[PATH_MAX];



			/* Adjust symbol to map to file offset */

			if (adjust_kernel_syms)

				sym.st_value -= shdr.sh_addr - shdr.sh_offset;



			if (strcmp(section_name,

				   (curr_dso->short_name +

				    dso->short_name_len)) == 0)

				goto new_symbol;



			if (strcmp(section_name, ".text") == 0) {

				/*

				 * The initial kernel mapping is based on

				 * kallsyms and identity maps.  Overwrite it to

				 * map to the kernel dso.

				 */

				if (remap_kernel && dso->kernel) {

					remap_kernel = false;

					map->start = shdr.sh_addr +

						     ref_reloc(kmap);

					map->end = map->start + shdr.sh_size;

					map->pgoff = shdr.sh_offset;

					map->map_ip = map__map_ip;

					map->unmap_ip = map__unmap_ip;

					/* Ensure maps are correctly ordered */

					if (kmaps) {

						map__get(map);

						map_groups__remove(kmaps, map);

						map_groups__insert(kmaps, map);

						map__put(map);

					}

				}



				/*

				 * The initial module mapping is based on

				 * /proc/modules mapped to offset zero.

				 * Overwrite it to map to the module dso.

				 */

				if (remap_kernel && kmodule) {

					remap_kernel = false;

					map->pgoff = shdr.sh_offset;

				}



				curr_map = map;

				curr_dso = dso;

				goto new_symbol;

			}



			if (!kmap)

				goto new_symbol;



			snprintf(dso_name, sizeof(dso_name),

				 "%s%s", dso->short_name, section_name);



			curr_map = map_groups__find_by_name(kmaps, dso_name);

			if (curr_map == NULL) {

				u64 start = sym.st_value;



				if (kmodule)

					start += map->start + shdr.sh_offset;



				curr_dso = dso__new(dso_name);

				if (curr_dso == NULL)

			if (dso__process_kernel_symbol(dso, map, &sym, &shdr, kmaps, kmap, &curr_dso, &curr_map,

						       section_name, adjust_kernel_syms, kmodule, &remap_kernel))

				goto out_elf_end;

				curr_dso->kernel = dso->kernel;

				curr_dso->long_name = dso->long_name;

				curr_dso->long_name_len = dso->long_name_len;

				curr_map = map__new2(start, curr_dso);

				dso__put(curr_dso);

				if (curr_map == NULL) {

					goto out_elf_end;

				}

				if (adjust_kernel_syms) {

					curr_map->start = shdr.sh_addr +

							  ref_reloc(kmap);

					curr_map->end = curr_map->start +

							shdr.sh_size;

					curr_map->pgoff = shdr.sh_offset;

				} else {

					curr_map->map_ip = identity__map_ip;

					curr_map->unmap_ip = identity__map_ip;

				}

				curr_dso->symtab_type = dso->symtab_type;

				map_groups__insert(kmaps, curr_map);

				/*

				 * Add it before we drop the referece to curr_map,

				 * i.e. while we still are sure to have a reference

				 * to this DSO via curr_map->dso.

				 */

				dsos__add(&map->groups->machine->dsos, curr_dso);

				/* kmaps already got it */

				map__put(curr_map);

				dso__set_loaded(curr_dso);

			} else

				curr_dso = curr_map->dso;

		} else if ((used_opd && runtime_ss->adjust_symbols) ||

			   (!used_opd && syms_ss->adjust_symbols)) {

			pr_debug4("%s: adjusting symbol: st_value: %#" PRIx64 " "
@@ -1077,7 +1088,7 @@ int dso__load_sym(struct dso *dso, struct map *map, struct symsrc *syms_ss, 
				  (u64)shdr.sh_offset);

			sym.st_value -= shdr.sh_addr - shdr.sh_offset;

		}

new_symbol:



		demangled = demangle_sym(dso, kmodule, elf_name);

		if (demangled != NULL)

			elf_name = demangled;

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