From: Athira Rajeev Date: Fri, 11 Aug 2023 05:15:46 +0000 (+0530) Subject: perf symbols: Fix DSO kernel load and symbol process to correctly map DSO to its... X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=e59fea47f83e8a9ac5b772d140a0d67d50ba0ed8;p=tomoyo%2Ftomoyo-test1.git perf symbols: Fix DSO kernel load and symbol process to correctly map DSO to its long_name, type and adjust_symbols Test "object code reading" fails sometimes for kernel address as below: Reading object code for memory address: 0xc000000000004c3c File is: [kernel.kallsyms] On file address is: 0x14c3c dso__data_read_offset failed test child finished with -1 ---- end ---- Object code reading: FAILED! Here dso__data_read_offset() fails for symbol address 0xc000000000004c3c. This is because the DSO long_name here is "[kernel.kallsyms]" and hence open_dso() fails to open this file. There is an incorrect DSO to map handling here. The key points here are: - The DSO long_name is set to "[kernel.kallsyms]". This file is not present and hence returns error - The DSO binary type is set to DSO_BINARY_TYPE__NOT_FOUND - The DSO adjust_symbols member is set to zero In the end dso__data_read_offset() returns -1 and the address 0x14c3c can not be resolved. Hence the test fails. But the address actually maps to the kernel DSO # objdump -z -d --start-address=0xc000000000004c3c --stop-address=0xc000000000004cbc /home/athira/linux/vmlinux /home/athira/linux/vmlinux: file format elf64-powerpcle Disassembly of section .head.text: c000000000004c3c : c000000000004c3c: a6 02 9b 7d mfsrr1 r12 c000000000004c40: 78 13 42 7c mr r2,r2 c000000000004c44: 18 00 4d e9 ld r10,24(r13) c000000000004c48: 60 c6 4a 61 ori r10,r10,50784 c000000000004c4c: a6 03 49 7d mtctr r10 Fix dso__process_kernel_symbol() to set the binary_type and adjust_symbols members. dso->adjust_symbols is used by map__rip_2objdump() which converts the symbol start address to the objdump address. Also set dso->long_name in dso__load_vmlinux(). Suggested-by: Adrian Hunter Signed-off-by: Athira Rajeev Acked-by: Adrian Hunter Cc: Disha Goel Cc: Ian Rogers Cc: Jiri Olsa Cc: Kajol Jain Cc: Madhavan Srinivasan Cc: Namhyung Kim Cc: linuxppc-dev@lists.ozlabs.org Link: https://lore.kernel.org/r/20230811051546.70039-1-atrajeev@linux.vnet.ibm.com Signed-off-by: Arnaldo Carvalho de Melo --- diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c index 8bd466d1c2bd..95e99c332d7e 100644 --- a/tools/perf/util/symbol-elf.c +++ b/tools/perf/util/symbol-elf.c @@ -1440,6 +1440,8 @@ static int dso__process_kernel_symbol(struct dso *dso, struct map *map, curr_dso->kernel = dso->kernel; curr_dso->long_name = dso->long_name; curr_dso->long_name_len = dso->long_name_len; + curr_dso->binary_type = dso->binary_type; + curr_dso->adjust_symbols = dso->adjust_symbols; curr_map = map__new2(start, curr_dso); dso__put(curr_dso); if (curr_map == NULL) diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c index f849f9ef68e6..3f36675b7c8f 100644 --- a/tools/perf/util/symbol.c +++ b/tools/perf/util/symbol.c @@ -2204,15 +2204,20 @@ int dso__load_vmlinux(struct dso *dso, struct map *map, if (symsrc__init(&ss, dso, symfs_vmlinux, symtab_type)) return -1; + /* + * dso__load_sym() may copy 'dso' which will result in the copies having + * an incorrect long name unless we set it here first. + */ + dso__set_long_name(dso, vmlinux, vmlinux_allocated); + if (dso->kernel == DSO_SPACE__KERNEL_GUEST) + dso->binary_type = DSO_BINARY_TYPE__GUEST_VMLINUX; + else + dso->binary_type = DSO_BINARY_TYPE__VMLINUX; + err = dso__load_sym(dso, map, &ss, &ss, 0); symsrc__destroy(&ss); if (err > 0) { - if (dso->kernel == DSO_SPACE__KERNEL_GUEST) - dso->binary_type = DSO_BINARY_TYPE__GUEST_VMLINUX; - else - dso->binary_type = DSO_BINARY_TYPE__VMLINUX; - dso__set_long_name(dso, vmlinux, vmlinux_allocated); dso__set_loaded(dso); pr_debug("Using %s for symbols\n", symfs_vmlinux); }