From ed9adb2035b5be5896d465b19040262be5f4a824 Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Wed, 8 May 2019 15:20:03 +0200 Subject: perf machine: Read also the end of the kernel We mark the end of kernel based on the first module, but that could cover some bpf program maps. Reading _etext symbol if it's present to get precise kernel map end. Signed-off-by: Jiri Olsa Acked-by: Song Liu Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Andi Kleen Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Stanislav Fomichev Cc: Thomas Richter Link: http://lkml.kernel.org/r/20190508132010.14512-6-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/machine.c | 27 ++++++++++++++++++--------- 1 file changed, 18 insertions(+), 9 deletions(-) (limited to 'tools') diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c index 28a9541c4835..dc7aafe45a2b 100644 --- a/tools/perf/util/machine.c +++ b/tools/perf/util/machine.c @@ -924,7 +924,8 @@ const char *ref_reloc_sym_names[] = {"_text", "_stext", NULL}; * symbol_name if it's not that important. */ static int machine__get_running_kernel_start(struct machine *machine, - const char **symbol_name, u64 *start) + const char **symbol_name, + u64 *start, u64 *end) { char filename[PATH_MAX]; int i, err = -1; @@ -949,6 +950,11 @@ static int machine__get_running_kernel_start(struct machine *machine, *symbol_name = name; *start = addr; + + err = kallsyms__get_function_start(filename, "_etext", &addr); + if (!err) + *end = addr; + return 0; } @@ -1441,7 +1447,7 @@ int machine__create_kernel_maps(struct machine *machine) struct dso *kernel = machine__get_kernel(machine); const char *name = NULL; struct map *map; - u64 addr = 0; + u64 start = 0, end = ~0ULL; int ret; if (kernel == NULL) @@ -1460,9 +1466,9 @@ int machine__create_kernel_maps(struct machine *machine) "continuing anyway...\n", machine->pid); } - if (!machine__get_running_kernel_start(machine, &name, &addr)) { + if (!machine__get_running_kernel_start(machine, &name, &start, &end)) { if (name && - map__set_kallsyms_ref_reloc_sym(machine->vmlinux_map, name, addr)) { + map__set_kallsyms_ref_reloc_sym(machine->vmlinux_map, name, start)) { machine__destroy_kernel_maps(machine); ret = -1; goto out_put; @@ -1472,16 +1478,19 @@ int machine__create_kernel_maps(struct machine *machine) * we have a real start address now, so re-order the kmaps * assume it's the last in the kmaps */ - machine__update_kernel_mmap(machine, addr, ~0ULL); + machine__update_kernel_mmap(machine, start, end); } if (machine__create_extra_kernel_maps(machine, kernel)) pr_debug("Problems creating extra kernel maps, continuing anyway...\n"); - /* update end address of the kernel map using adjacent module address */ - map = map__next(machine__kernel_map(machine)); - if (map) - machine__set_kernel_mmap(machine, addr, map->start); + if (end == ~0ULL) { + /* update end address of the kernel map using adjacent module address */ + map = map__next(machine__kernel_map(machine)); + if (map) + machine__set_kernel_mmap(machine, start, map->start); + } + out_put: dso__put(kernel); return ret; -- cgit v1.2.3