diff --git a/tools/perf/arch/x86/util/Build b/tools/perf/arch/x86/util/Build index f95e6f46ef0d..aa1ce5f6cc00 100644 --- a/tools/perf/arch/x86/util/Build +++ b/tools/perf/arch/x86/util/Build @@ -4,6 +4,7 @@ libperf-y += pmu.o libperf-y += kvm-stat.o libperf-y += perf_regs.o libperf-y += group.o +libperf-y += machine.o libperf-$(CONFIG_DWARF) += dwarf-regs.o libperf-$(CONFIG_BPF_PROLOGUE) += dwarf-regs.o diff --git a/tools/perf/arch/x86/util/machine.c b/tools/perf/arch/x86/util/machine.c new file mode 100644 index 000000000000..4520ac53caa9 --- /dev/null +++ b/tools/perf/arch/x86/util/machine.c @@ -0,0 +1,103 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include + +#include "../../util/machine.h" +#include "../../util/map.h" +#include "../../util/symbol.h" +#include "../../util/sane_ctype.h" + +#include + +#if defined(__x86_64__) + +struct extra_kernel_map_info { + int cnt; + int max_cnt; + struct extra_kernel_map *maps; + bool get_entry_trampolines; + u64 entry_trampoline; +}; + +static int add_extra_kernel_map(struct extra_kernel_map_info *mi, u64 start, + u64 end, u64 pgoff, const char *name) +{ + if (mi->cnt >= mi->max_cnt) { + void *buf; + size_t sz; + + mi->max_cnt = mi->max_cnt ? mi->max_cnt * 2 : 32; + sz = sizeof(struct extra_kernel_map) * mi->max_cnt; + buf = realloc(mi->maps, sz); + if (!buf) + return -1; + mi->maps = buf; + } + + mi->maps[mi->cnt].start = start; + mi->maps[mi->cnt].end = end; + mi->maps[mi->cnt].pgoff = pgoff; + strlcpy(mi->maps[mi->cnt].name, name, KMAP_NAME_LEN); + + mi->cnt += 1; + + return 0; +} + +static int find_extra_kernel_maps(void *arg, const char *name, char type, + u64 start) +{ + struct extra_kernel_map_info *mi = arg; + + if (!mi->entry_trampoline && kallsyms2elf_binding(type) == STB_GLOBAL && + !strcmp(name, "_entry_trampoline")) { + mi->entry_trampoline = start; + return 0; + } + + if (is_entry_trampoline(name)) { + u64 end = start + page_size; + + return add_extra_kernel_map(mi, start, end, 0, name); + } + + return 0; +} + +int machine__create_extra_kernel_maps(struct machine *machine, + struct dso *kernel) +{ + struct extra_kernel_map_info mi = { .cnt = 0, }; + char filename[PATH_MAX]; + int ret; + int i; + + machine__get_kallsyms_filename(machine, filename, PATH_MAX); + + if (symbol__restricted_filename(filename, "/proc/kallsyms")) + return 0; + + ret = kallsyms__parse(filename, &mi, find_extra_kernel_maps); + if (ret) + goto out_free; + + if (!mi.entry_trampoline) + goto out_free; + + for (i = 0; i < mi.cnt; i++) { + struct extra_kernel_map *xm = &mi.maps[i]; + + xm->pgoff = mi.entry_trampoline; + ret = machine__create_extra_kernel_map(machine, kernel, xm); + if (ret) + goto out_free; + } + + machine->trampolines_mapped = mi.cnt; +out_free: + free(mi.maps); + return ret; +} + +#endif diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c index 355d23bcd443..dd7ab0731167 100644 --- a/tools/perf/util/machine.c +++ b/tools/perf/util/machine.c @@ -807,8 +807,8 @@ struct process_args { u64 start; }; -static void machine__get_kallsyms_filename(struct machine *machine, char *buf, - size_t bufsz) +void machine__get_kallsyms_filename(struct machine *machine, char *buf, + size_t bufsz) { if (machine__is_default_guest(machine)) scnprintf(buf, bufsz, "%s", symbol_conf.default_guest_kallsyms); @@ -851,17 +851,9 @@ static int machine__get_running_kernel_start(struct machine *machine, return 0; } -/* Kernel-space maps for symbols that are outside the main kernel map and module maps */ -struct extra_kernel_map { - u64 start; - u64 end; - u64 pgoff; - char name[KMAP_NAME_LEN]; -}; - -static int machine__create_extra_kernel_map(struct machine *machine, - struct dso *kernel, - struct extra_kernel_map *xm) +int machine__create_extra_kernel_map(struct machine *machine, + struct dso *kernel, + struct extra_kernel_map *xm) { struct kmap *kmap; struct map *map; @@ -923,9 +915,33 @@ static u64 find_entry_trampoline(struct dso *dso) int machine__map_x86_64_entry_trampolines(struct machine *machine, struct dso *kernel) { - u64 pgoff = find_entry_trampoline(kernel); + struct map_groups *kmaps = &machine->kmaps; + struct maps *maps = &kmaps->maps; int nr_cpus_avail, cpu; + bool found = false; + struct map *map; + u64 pgoff; + /* + * In the vmlinux case, pgoff is a virtual address which must now be + * mapped to a vmlinux offset. + */ + for (map = maps__first(maps); map; map = map__next(map)) { + struct kmap *kmap = __map__kmap(map); + struct map *dest_map; + + if (!kmap || !is_entry_trampoline(kmap->name)) + continue; + + dest_map = map_groups__find(kmaps, map->pgoff); + if (dest_map != map) + map->pgoff = dest_map->map_ip(dest_map, map->pgoff); + found = true; + } + if (found || machine->trampolines_mapped) + return 0; + + pgoff = find_entry_trampoline(kernel); if (!pgoff) return 0; @@ -948,6 +964,14 @@ int machine__map_x86_64_entry_trampolines(struct machine *machine, return -1; } + machine->trampolines_mapped = nr_cpus_avail; + + return 0; +} + +int __weak machine__create_extra_kernel_maps(struct machine *machine __maybe_unused, + struct dso *kernel __maybe_unused) +{ return 0; } @@ -1306,9 +1330,8 @@ int machine__create_kernel_maps(struct machine *machine) return -1; ret = __machine__create_kernel_maps(machine, kernel); - dso__put(kernel); if (ret < 0) - return -1; + goto out_put; if (symbol_conf.use_modules && machine__create_modules(machine) < 0) { if (machine__is_host(machine)) @@ -1323,7 +1346,8 @@ int machine__create_kernel_maps(struct machine *machine) if (name && map__set_kallsyms_ref_reloc_sym(machine->vmlinux_map, name, addr)) { machine__destroy_kernel_maps(machine); - return -1; + ret = -1; + goto out_put; } /* we have a real start address now, so re-order the kmaps */ @@ -1339,12 +1363,16 @@ int machine__create_kernel_maps(struct machine *machine) map__put(map); } + 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); - - return 0; +out_put: + dso__put(kernel); + return ret; } static bool machine__uses_kcore(struct machine *machine) diff --git a/tools/perf/util/machine.h b/tools/perf/util/machine.h index b6a1c3eb3d65..1de7660d93e9 100644 --- a/tools/perf/util/machine.h +++ b/tools/perf/util/machine.h @@ -56,6 +56,7 @@ struct machine { void *priv; u64 db_id; }; + bool trampolines_mapped; }; static inline struct threads *machine__threads(struct machine *machine, pid_t tid) @@ -268,6 +269,24 @@ int machine__set_current_tid(struct machine *machine, int cpu, pid_t pid, */ char *machine__resolve_kernel_addr(void *vmachine, unsigned long long *addrp, char **modp); +void machine__get_kallsyms_filename(struct machine *machine, char *buf, + size_t bufsz); + +int machine__create_extra_kernel_maps(struct machine *machine, + struct dso *kernel); + +/* Kernel-space maps for symbols that are outside the main kernel map and module maps */ +struct extra_kernel_map { + u64 start; + u64 end; + u64 pgoff; + char name[KMAP_NAME_LEN]; +}; + +int machine__create_extra_kernel_map(struct machine *machine, + struct dso *kernel, + struct extra_kernel_map *xm); + int machine__map_x86_64_entry_trampolines(struct machine *machine, struct dso *kernel); diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c index cdddae67f40c..8c84437f2a10 100644 --- a/tools/perf/util/symbol.c +++ b/tools/perf/util/symbol.c @@ -1158,6 +1158,7 @@ static int dso__load_kcore(struct dso *dso, struct map *map, struct map_groups *kmaps = map__kmaps(map); struct kcore_mapfn_data md; struct map *old_map, *new_map, *replacement_map = NULL; + struct machine *machine; bool is_64_bit; int err, fd; char kcore_filename[PATH_MAX]; @@ -1166,6 +1167,8 @@ static int dso__load_kcore(struct dso *dso, struct map *map, if (!kmaps) return -EINVAL; + machine = kmaps->machine; + /* This function requires that the map is the kernel map */ if (!__map__is_kernel(map)) return -EINVAL; @@ -1209,6 +1212,7 @@ static int dso__load_kcore(struct dso *dso, struct map *map, map_groups__remove(kmaps, old_map); old_map = next; } + machine->trampolines_mapped = false; /* Find the kernel map using the '_stext' symbol */ if (!kallsyms__get_function_start(kallsyms_filename, "_stext", &stext)) { @@ -1245,6 +1249,19 @@ static int dso__load_kcore(struct dso *dso, struct map *map, map__put(new_map); } + if (machine__is(machine, "x86_64")) { + u64 addr; + + /* + * If one of the corresponding symbols is there, assume the + * entry trampoline maps are too. + */ + if (!kallsyms__get_function_start(kallsyms_filename, + ENTRY_TRAMPOLINE_NAME, + &addr)) + machine->trampolines_mapped = true; + } + /* * Set the data type and long name so that kcore can be read via * dso__data_read_addr().