From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751736AbaBIIBZ (ORCPT ); Sun, 9 Feb 2014 03:01:25 -0500 Received: from mail-ea0-f171.google.com ([209.85.215.171]:34951 "EHLO mail-ea0-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751481AbaBIIBY (ORCPT ); Sun, 9 Feb 2014 03:01:24 -0500 Date: Sun, 9 Feb 2014 09:01:18 +0100 From: Ingo Molnar To: Linus Torvalds Cc: linux-kernel@vger.kernel.org, Peter Zijlstra , Arnaldo Carvalho de Melo , Thomas Gleixner , Andrew Morton Subject: [GIT PULL] perf fixes Message-ID: <20140209080118.GA17003@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Linus, Please pull the latest perf-urgent-for-linus git tree from: git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git perf-urgent-for-linus # HEAD: 2737fce8bc8dea2852289df29b4f92e6a7fb7c91 Merge tag 'perf-urgent-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent Tooling fixes, mostly related to the KASLR fallout, but also other fixes. Thanks, Ingo ------------------> Adrian Hunter (9): perf symbols: Fix symbol annotation for relocated kernel perf tools: Add kallsyms__get_function_start() perf machine: Add machine__get_kallsyms_filename() perf machine: Set up ref_reloc_sym in machine__create_kernel_maps() perf record: Get ref_reloc_sym from kernel map perf symbols: Prevent the use of kcore if the kernel has moved perf tests: No need to set up ref_reloc_sym perf tools: Adjust kallsyms for relocated kernel perf buildid-cache: Check relocation when checking for existing kcore Avi Kivity (1): perf tools: Demangle kernel and kernel module symbols too Baruch Siach (1): perf/doc: Remove mention of non-existent set_perf_event_pending() from design.txt Francesco Fusco (1): perf tools: Fix include for non x86 architectures Peter Zijlstra (1): perf tools: Fix AAAAARGH64 memory barriers tools/perf/builtin-buildid-cache.c | 33 ++++++++++++++++--- tools/perf/builtin-record.c | 10 ++---- tools/perf/design.txt | 1 - tools/perf/perf.h | 4 +-- tools/perf/tests/vmlinux-kallsyms.c | 10 ------ tools/perf/util/event.c | 36 ++++++++++---------- tools/perf/util/event.h | 6 ++-- tools/perf/util/include/asm/hash.h | 6 ++++ tools/perf/util/machine.c | 42 +++++++++++++++++++----- tools/perf/util/machine.h | 2 ++ tools/perf/util/map.c | 5 +-- tools/perf/util/map.h | 1 + tools/perf/util/symbol-elf.c | 4 ++- tools/perf/util/symbol.c | 65 +++++++++++++++++++++++++++++++++---- 14 files changed, 162 insertions(+), 63 deletions(-) create mode 100644 tools/perf/util/include/asm/hash.h diff --git a/tools/perf/builtin-buildid-cache.c b/tools/perf/builtin-buildid-cache.c index cfede86..b22dbb1 100644 --- a/tools/perf/builtin-buildid-cache.c +++ b/tools/perf/builtin-buildid-cache.c @@ -63,11 +63,35 @@ static int build_id_cache__kcore_dir(char *dir, size_t sz) return 0; } +static bool same_kallsyms_reloc(const char *from_dir, char *to_dir) +{ + char from[PATH_MAX]; + char to[PATH_MAX]; + const char *name; + u64 addr1 = 0, addr2 = 0; + int i; + + scnprintf(from, sizeof(from), "%s/kallsyms", from_dir); + scnprintf(to, sizeof(to), "%s/kallsyms", to_dir); + + for (i = 0; (name = ref_reloc_sym_names[i]) != NULL; i++) { + addr1 = kallsyms__get_function_start(from, name); + if (addr1) + break; + } + + if (name) + addr2 = kallsyms__get_function_start(to, name); + + return addr1 == addr2; +} + static int build_id_cache__kcore_existing(const char *from_dir, char *to_dir, size_t to_dir_sz) { char from[PATH_MAX]; char to[PATH_MAX]; + char to_subdir[PATH_MAX]; struct dirent *dent; int ret = -1; DIR *d; @@ -86,10 +110,11 @@ static int build_id_cache__kcore_existing(const char *from_dir, char *to_dir, continue; scnprintf(to, sizeof(to), "%s/%s/modules", to_dir, dent->d_name); - if (!compare_proc_modules(from, to)) { - scnprintf(to, sizeof(to), "%s/%s", to_dir, - dent->d_name); - strlcpy(to_dir, to, to_dir_sz); + scnprintf(to_subdir, sizeof(to_subdir), "%s/%s", + to_dir, dent->d_name); + if (!compare_proc_modules(from, to) && + same_kallsyms_reloc(from_dir, to_subdir)) { + strlcpy(to_dir, to_subdir, to_dir_sz); ret = 0; break; } diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index 3c394bf..af47531 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -287,10 +287,7 @@ static void perf_event__synthesize_guest_os(struct machine *machine, void *data) * have no _text sometimes. */ err = perf_event__synthesize_kernel_mmap(tool, process_synthesized_event, - machine, "_text"); - if (err < 0) - err = perf_event__synthesize_kernel_mmap(tool, process_synthesized_event, - machine, "_stext"); + machine); if (err < 0) pr_err("Couldn't record guest kernel [%d]'s reference" " relocation symbol.\n", machine->pid); @@ -457,10 +454,7 @@ static int __cmd_record(struct record *rec, int argc, const char **argv) } err = perf_event__synthesize_kernel_mmap(tool, process_synthesized_event, - machine, "_text"); - if (err < 0) - err = perf_event__synthesize_kernel_mmap(tool, process_synthesized_event, - machine, "_stext"); + machine); if (err < 0) pr_err("Couldn't record kernel reference relocation symbol\n" "Symbol resolution may be skewed if relocation was used (e.g. kexec).\n" diff --git a/tools/perf/design.txt b/tools/perf/design.txt index 67e5d0c..63a0e6f 100644 --- a/tools/perf/design.txt +++ b/tools/perf/design.txt @@ -454,7 +454,6 @@ So to start with, in order to add HAVE_PERF_EVENTS to your Kconfig, you will need at least this: - asm/perf_event.h - a basic stub will suffice at first - support for atomic64 types (and associated helper functions) - - set_perf_event_pending() implemented If your architecture does have hardware capabilities, you can override the weak stub hw_perf_event_init() to register hardware counters. diff --git a/tools/perf/perf.h b/tools/perf/perf.h index 7daa806..e84fa26 100644 --- a/tools/perf/perf.h +++ b/tools/perf/perf.h @@ -100,8 +100,8 @@ #ifdef __aarch64__ #define mb() asm volatile("dmb ish" ::: "memory") -#define wmb() asm volatile("dmb ishld" ::: "memory") -#define rmb() asm volatile("dmb ishst" ::: "memory") +#define wmb() asm volatile("dmb ishst" ::: "memory") +#define rmb() asm volatile("dmb ishld" ::: "memory") #define cpu_relax() asm volatile("yield" ::: "memory") #endif diff --git a/tools/perf/tests/vmlinux-kallsyms.c b/tools/perf/tests/vmlinux-kallsyms.c index 2bd13ed..3d90880 100644 --- a/tools/perf/tests/vmlinux-kallsyms.c +++ b/tools/perf/tests/vmlinux-kallsyms.c @@ -26,7 +26,6 @@ int test__vmlinux_matches_kallsyms(void) struct map *kallsyms_map, *vmlinux_map; struct machine kallsyms, vmlinux; enum map_type type = MAP__FUNCTION; - struct ref_reloc_sym ref_reloc_sym = { .name = "_stext", }; u64 mem_start, mem_end; /* @@ -70,14 +69,6 @@ int test__vmlinux_matches_kallsyms(void) */ kallsyms_map = machine__kernel_map(&kallsyms, type); - sym = map__find_symbol_by_name(kallsyms_map, ref_reloc_sym.name, NULL); - if (sym == NULL) { - pr_debug("dso__find_symbol_by_name "); - goto out; - } - - ref_reloc_sym.addr = UM(sym->start); - /* * Step 5: * @@ -89,7 +80,6 @@ int test__vmlinux_matches_kallsyms(void) } vmlinux_map = machine__kernel_map(&vmlinux, type); - map__kmap(vmlinux_map)->ref_reloc_sym = &ref_reloc_sym; /* * Step 6: diff --git a/tools/perf/util/event.c b/tools/perf/util/event.c index 1fc1c2f..b0f3ca8 100644 --- a/tools/perf/util/event.c +++ b/tools/perf/util/event.c @@ -470,23 +470,32 @@ static int find_symbol_cb(void *arg, const char *name, char type, return 1; } +u64 kallsyms__get_function_start(const char *kallsyms_filename, + const char *symbol_name) +{ + struct process_symbol_args args = { .name = symbol_name, }; + + if (kallsyms__parse(kallsyms_filename, &args, find_symbol_cb) <= 0) + return 0; + + return args.start; +} + int perf_event__synthesize_kernel_mmap(struct perf_tool *tool, perf_event__handler_t process, - struct machine *machine, - const char *symbol_name) + struct machine *machine) { size_t size; - const char *filename, *mmap_name; - char path[PATH_MAX]; + const char *mmap_name; char name_buff[PATH_MAX]; struct map *map; + struct kmap *kmap; int err; /* * We should get this from /sys/kernel/sections/.text, but till that is * available use this, and after it is use this as a fallback for older * kernels. */ - struct process_symbol_args args = { .name = symbol_name, }; union perf_event *event = zalloc((sizeof(event->mmap) + machine->id_hdr_size)); if (event == NULL) { @@ -502,30 +511,19 @@ int perf_event__synthesize_kernel_mmap(struct perf_tool *tool, * see kernel/perf_event.c __perf_event_mmap */ event->header.misc = PERF_RECORD_MISC_KERNEL; - filename = "/proc/kallsyms"; } else { event->header.misc = PERF_RECORD_MISC_GUEST_KERNEL; - if (machine__is_default_guest(machine)) - filename = (char *) symbol_conf.default_guest_kallsyms; - else { - sprintf(path, "%s/proc/kallsyms", machine->root_dir); - filename = path; - } - } - - if (kallsyms__parse(filename, &args, find_symbol_cb) <= 0) { - free(event); - return -ENOENT; } map = machine->vmlinux_maps[MAP__FUNCTION]; + kmap = map__kmap(map); size = snprintf(event->mmap.filename, sizeof(event->mmap.filename), - "%s%s", mmap_name, symbol_name) + 1; + "%s%s", mmap_name, kmap->ref_reloc_sym->name) + 1; size = PERF_ALIGN(size, sizeof(u64)); event->mmap.header.type = PERF_RECORD_MMAP; event->mmap.header.size = (sizeof(event->mmap) - (sizeof(event->mmap.filename) - size) + machine->id_hdr_size); - event->mmap.pgoff = args.start; + event->mmap.pgoff = kmap->ref_reloc_sym->addr; event->mmap.start = map->start; event->mmap.len = map->end - event->mmap.start; event->mmap.pid = machine->pid; diff --git a/tools/perf/util/event.h b/tools/perf/util/event.h index faf6e21..851fa06 100644 --- a/tools/perf/util/event.h +++ b/tools/perf/util/event.h @@ -214,8 +214,7 @@ int perf_event__synthesize_threads(struct perf_tool *tool, struct machine *machine, bool mmap_data); int perf_event__synthesize_kernel_mmap(struct perf_tool *tool, perf_event__handler_t process, - struct machine *machine, - const char *symbol_name); + struct machine *machine); int perf_event__synthesize_modules(struct perf_tool *tool, perf_event__handler_t process, @@ -279,4 +278,7 @@ size_t perf_event__fprintf_mmap2(union perf_event *event, FILE *fp); size_t perf_event__fprintf_task(union perf_event *event, FILE *fp); size_t perf_event__fprintf(union perf_event *event, FILE *fp); +u64 kallsyms__get_function_start(const char *kallsyms_filename, + const char *symbol_name); + #endif /* __PERF_RECORD_H */ diff --git a/tools/perf/util/include/asm/hash.h b/tools/perf/util/include/asm/hash.h new file mode 100644 index 0000000..d82b170b --- /dev/null +++ b/tools/perf/util/include/asm/hash.h @@ -0,0 +1,6 @@ +#ifndef __ASM_GENERIC_HASH_H +#define __ASM_GENERIC_HASH_H + +/* Stub */ + +#endif /* __ASM_GENERIC_HASH_H */ diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c index ded7459..c872991 100644 --- a/tools/perf/util/machine.c +++ b/tools/perf/util/machine.c @@ -496,19 +496,22 @@ static int symbol__in_kernel(void *arg, const char *name, return 1; } +static 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); + else + scnprintf(buf, bufsz, "%s/proc/kallsyms", machine->root_dir); +} + /* Figure out the start address of kernel map from /proc/kallsyms */ static u64 machine__get_kernel_start_addr(struct machine *machine) { - const char *filename; - char path[PATH_MAX]; + char filename[PATH_MAX]; struct process_args args; - if (machine__is_default_guest(machine)) - filename = (char *)symbol_conf.default_guest_kallsyms; - else { - sprintf(path, "%s/proc/kallsyms", machine->root_dir); - filename = path; - } + machine__get_kallsyms_filename(machine, filename, PATH_MAX); if (symbol__restricted_filename(filename, "/proc/kallsyms")) return 0; @@ -829,9 +832,25 @@ static int machine__create_modules(struct machine *machine) return 0; } +const char *ref_reloc_sym_names[] = {"_text", "_stext", NULL}; + int machine__create_kernel_maps(struct machine *machine) { struct dso *kernel = machine__get_kernel(machine); + char filename[PATH_MAX]; + const char *name; + u64 addr = 0; + int i; + + machine__get_kallsyms_filename(machine, filename, PATH_MAX); + + for (i = 0; (name = ref_reloc_sym_names[i]) != NULL; i++) { + addr = kallsyms__get_function_start(filename, name); + if (addr) + break; + } + if (!addr) + return -1; if (kernel == NULL || __machine__create_kernel_maps(machine, kernel) < 0) @@ -850,6 +869,13 @@ int machine__create_kernel_maps(struct machine *machine) * Now that we have all the maps created, just set the ->end of them: */ map_groups__fixup_end(&machine->kmaps); + + if (maps__set_kallsyms_ref_reloc_sym(machine->vmlinux_maps, name, + addr)) { + machine__destroy_kernel_maps(machine); + return -1; + } + return 0; } diff --git a/tools/perf/util/machine.h b/tools/perf/util/machine.h index 4771330..f77e91e 100644 --- a/tools/perf/util/machine.h +++ b/tools/perf/util/machine.h @@ -18,6 +18,8 @@ union perf_event; #define HOST_KERNEL_ID (-1) #define DEFAULT_GUEST_KERNEL_ID (0) +extern const char *ref_reloc_sym_names[]; + struct machine { struct rb_node rb_node; pid_t pid; diff --git a/tools/perf/util/map.c b/tools/perf/util/map.c index 3b97513..39cd2d0 100644 --- a/tools/perf/util/map.c +++ b/tools/perf/util/map.c @@ -39,6 +39,7 @@ void map__init(struct map *map, enum map_type type, map->start = start; map->end = end; map->pgoff = pgoff; + map->reloc = 0; map->dso = dso; map->map_ip = map__map_ip; map->unmap_ip = map__unmap_ip; @@ -288,7 +289,7 @@ u64 map__rip_2objdump(struct map *map, u64 rip) if (map->dso->rel) return rip - map->pgoff; - return map->unmap_ip(map, rip); + return map->unmap_ip(map, rip) - map->reloc; } /** @@ -311,7 +312,7 @@ u64 map__objdump_2mem(struct map *map, u64 ip) if (map->dso->rel) return map->unmap_ip(map, ip + map->pgoff); - return ip; + return ip + map->reloc; } void map_groups__init(struct map_groups *mg) diff --git a/tools/perf/util/map.h b/tools/perf/util/map.h index 18068c6..257e513 100644 --- a/tools/perf/util/map.h +++ b/tools/perf/util/map.h @@ -36,6 +36,7 @@ struct map { bool erange_warned; u32 priv; u64 pgoff; + u64 reloc; u32 maj, min; /* only valid for MMAP2 record */ u64 ino; /* only valid for MMAP2 record */ u64 ino_generation;/* only valid for MMAP2 record */ diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c index 7594567..3e9f336 100644 --- a/tools/perf/util/symbol-elf.c +++ b/tools/perf/util/symbol-elf.c @@ -751,6 +751,8 @@ int dso__load_sym(struct dso *dso, struct map *map, if (strcmp(elf_name, kmap->ref_reloc_sym->name)) continue; kmap->ref_reloc_sym->unrelocated_addr = sym.st_value; + map->reloc = kmap->ref_reloc_sym->addr - + kmap->ref_reloc_sym->unrelocated_addr; break; } } @@ -922,6 +924,7 @@ int dso__load_sym(struct dso *dso, struct map *map, (u64)shdr.sh_offset); sym.st_value -= shdr.sh_addr - shdr.sh_offset; } +new_symbol: /* * We need to figure out if the object was created from C++ sources * DWARF DW_compile_unit has this, but we don't always have access @@ -933,7 +936,6 @@ int dso__load_sym(struct dso *dso, struct map *map, if (demangled != NULL) elf_name = demangled; } -new_symbol: f = symbol__new(sym.st_value, sym.st_size, GELF_ST_BIND(sym.st_info), elf_name); free(demangled); diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c index 39ce9ad..a9d758a 100644 --- a/tools/perf/util/symbol.c +++ b/tools/perf/util/symbol.c @@ -627,7 +627,7 @@ static int dso__split_kallsyms_for_kcore(struct dso *dso, struct map *map, * kernel range is broken in several maps, named [kernel].N, as we don't have * the original ELF section names vmlinux have. */ -static int dso__split_kallsyms(struct dso *dso, struct map *map, +static int dso__split_kallsyms(struct dso *dso, struct map *map, u64 delta, symbol_filter_t filter) { struct map_groups *kmaps = map__kmap(map)->kmaps; @@ -692,6 +692,12 @@ static int dso__split_kallsyms(struct dso *dso, struct map *map, char dso_name[PATH_MAX]; struct dso *ndso; + if (delta) { + /* Kernel was relocated at boot time */ + pos->start -= delta; + pos->end -= delta; + } + if (count == 0) { curr_map = map; goto filter_symbol; @@ -721,6 +727,10 @@ static int dso__split_kallsyms(struct dso *dso, struct map *map, curr_map->map_ip = curr_map->unmap_ip = identity__map_ip; map_groups__insert(kmaps, curr_map); ++kernel_range; + } else if (delta) { + /* Kernel was relocated at boot time */ + pos->start -= delta; + pos->end -= delta; } filter_symbol: if (filter && filter(curr_map, pos)) { @@ -976,6 +986,23 @@ static int validate_kcore_modules(const char *kallsyms_filename, return 0; } +static int validate_kcore_addresses(const char *kallsyms_filename, + struct map *map) +{ + struct kmap *kmap = map__kmap(map); + + if (kmap->ref_reloc_sym && kmap->ref_reloc_sym->name) { + u64 start; + + start = kallsyms__get_function_start(kallsyms_filename, + kmap->ref_reloc_sym->name); + if (start != kmap->ref_reloc_sym->addr) + return -EINVAL; + } + + return validate_kcore_modules(kallsyms_filename, map); +} + struct kcore_mapfn_data { struct dso *dso; enum map_type type; @@ -1019,8 +1046,8 @@ static int dso__load_kcore(struct dso *dso, struct map *map, kallsyms_filename)) return -EINVAL; - /* All modules must be present at their original addresses */ - if (validate_kcore_modules(kallsyms_filename, map)) + /* Modules and kernel must be present at their original addresses */ + if (validate_kcore_addresses(kallsyms_filename, map)) return -EINVAL; md.dso = dso; @@ -1113,15 +1140,41 @@ out_err: return -EINVAL; } +/* + * If the kernel is relocated at boot time, kallsyms won't match. Compute the + * delta based on the relocation reference symbol. + */ +static int kallsyms__delta(struct map *map, const char *filename, u64 *delta) +{ + struct kmap *kmap = map__kmap(map); + u64 addr; + + if (!kmap->ref_reloc_sym || !kmap->ref_reloc_sym->name) + return 0; + + addr = kallsyms__get_function_start(filename, + kmap->ref_reloc_sym->name); + if (!addr) + return -1; + + *delta = addr - kmap->ref_reloc_sym->addr; + return 0; +} + int dso__load_kallsyms(struct dso *dso, const char *filename, struct map *map, symbol_filter_t filter) { + u64 delta = 0; + if (symbol__restricted_filename(filename, "/proc/kallsyms")) return -1; if (dso__load_all_kallsyms(dso, filename, map) < 0) return -1; + if (kallsyms__delta(map, filename, &delta)) + return -1; + symbols__fixup_duplicate(&dso->symbols[map->type]); symbols__fixup_end(&dso->symbols[map->type]); @@ -1133,7 +1186,7 @@ int dso__load_kallsyms(struct dso *dso, const char *filename, if (!dso__load_kcore(dso, map, filename)) return dso__split_kallsyms_for_kcore(dso, map, filter); else - return dso__split_kallsyms(dso, map, filter); + return dso__split_kallsyms(dso, map, delta, filter); } static int dso__load_perf_map(struct dso *dso, struct map *map, @@ -1424,7 +1477,7 @@ static int find_matching_kcore(struct map *map, char *dir, size_t dir_sz) continue; scnprintf(kallsyms_filename, sizeof(kallsyms_filename), "%s/%s/kallsyms", dir, dent->d_name); - if (!validate_kcore_modules(kallsyms_filename, map)) { + if (!validate_kcore_addresses(kallsyms_filename, map)) { strlcpy(dir, kallsyms_filename, dir_sz); ret = 0; break; @@ -1479,7 +1532,7 @@ static char *dso__find_kallsyms(struct dso *dso, struct map *map) if (fd != -1) { close(fd); /* If module maps match go with /proc/kallsyms */ - if (!validate_kcore_modules("/proc/kallsyms", map)) + if (!validate_kcore_addresses("/proc/kallsyms", map)) goto proc_kallsyms; }