diff options
Diffstat (limited to 'tools/perf/arch/x86/util/machine.c')
-rw-r--r-- | tools/perf/arch/x86/util/machine.c | 103 |
1 files changed, 103 insertions, 0 deletions
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 <linux/types.h> +#include <linux/string.h> +#include <stdlib.h> + +#include "../../util/machine.h" +#include "../../util/map.h" +#include "../../util/symbol.h" +#include "../../util/sane_ctype.h" + +#include <symbol/kallsyms.h> + +#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 |