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Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar: "Tooling fixes, mostly related to the KASLR fallout, but also other fixes" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf buildid-cache: Check relocation when checking for existing kcore perf tools: Adjust kallsyms for relocated kernel perf tests: No need to set up ref_reloc_sym perf symbols: Prevent the use of kcore if the kernel has moved perf record: Get ref_reloc_sym from kernel map perf machine: Set up ref_reloc_sym in machine__create_kernel_maps() perf machine: Add machine__get_kallsyms_filename() perf tools: Add kallsyms__get_function_start() perf symbols: Fix symbol annotation for relocated kernel perf tools: Fix include for non x86 architectures perf tools: Fix AAAAARGH64 memory barriers perf tools: Demangle kernel and kernel module symbols too perf/doc: Remove mention of non-existent set_perf_event_pending() from design.txt
This commit is contained in:
commit
6f2a1c1e78
@ -63,11 +63,35 @@ static int build_id_cache__kcore_dir(char *dir, size_t sz)
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return 0;
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}
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static bool same_kallsyms_reloc(const char *from_dir, char *to_dir)
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{
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char from[PATH_MAX];
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char to[PATH_MAX];
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const char *name;
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u64 addr1 = 0, addr2 = 0;
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int i;
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scnprintf(from, sizeof(from), "%s/kallsyms", from_dir);
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scnprintf(to, sizeof(to), "%s/kallsyms", to_dir);
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for (i = 0; (name = ref_reloc_sym_names[i]) != NULL; i++) {
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addr1 = kallsyms__get_function_start(from, name);
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if (addr1)
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break;
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}
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if (name)
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addr2 = kallsyms__get_function_start(to, name);
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return addr1 == addr2;
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}
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static int build_id_cache__kcore_existing(const char *from_dir, char *to_dir,
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size_t to_dir_sz)
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{
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char from[PATH_MAX];
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char to[PATH_MAX];
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char to_subdir[PATH_MAX];
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struct dirent *dent;
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int ret = -1;
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DIR *d;
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@ -86,10 +110,11 @@ static int build_id_cache__kcore_existing(const char *from_dir, char *to_dir,
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continue;
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scnprintf(to, sizeof(to), "%s/%s/modules", to_dir,
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dent->d_name);
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if (!compare_proc_modules(from, to)) {
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scnprintf(to, sizeof(to), "%s/%s", to_dir,
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dent->d_name);
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strlcpy(to_dir, to, to_dir_sz);
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scnprintf(to_subdir, sizeof(to_subdir), "%s/%s",
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to_dir, dent->d_name);
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if (!compare_proc_modules(from, to) &&
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same_kallsyms_reloc(from_dir, to_subdir)) {
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strlcpy(to_dir, to_subdir, to_dir_sz);
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ret = 0;
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break;
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}
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@ -287,10 +287,7 @@ static void perf_event__synthesize_guest_os(struct machine *machine, void *data)
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* have no _text sometimes.
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*/
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err = perf_event__synthesize_kernel_mmap(tool, process_synthesized_event,
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machine, "_text");
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if (err < 0)
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err = perf_event__synthesize_kernel_mmap(tool, process_synthesized_event,
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machine, "_stext");
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machine);
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if (err < 0)
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pr_err("Couldn't record guest kernel [%d]'s reference"
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" relocation symbol.\n", machine->pid);
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@ -457,10 +454,7 @@ static int __cmd_record(struct record *rec, int argc, const char **argv)
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}
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err = perf_event__synthesize_kernel_mmap(tool, process_synthesized_event,
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machine, "_text");
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if (err < 0)
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err = perf_event__synthesize_kernel_mmap(tool, process_synthesized_event,
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machine, "_stext");
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machine);
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if (err < 0)
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pr_err("Couldn't record kernel reference relocation symbol\n"
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"Symbol resolution may be skewed if relocation was used (e.g. kexec).\n"
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@ -454,7 +454,6 @@ So to start with, in order to add HAVE_PERF_EVENTS to your Kconfig, you
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will need at least this:
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- asm/perf_event.h - a basic stub will suffice at first
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- support for atomic64 types (and associated helper functions)
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- set_perf_event_pending() implemented
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If your architecture does have hardware capabilities, you can override the
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weak stub hw_perf_event_init() to register hardware counters.
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|
@ -100,8 +100,8 @@
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#ifdef __aarch64__
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#define mb() asm volatile("dmb ish" ::: "memory")
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#define wmb() asm volatile("dmb ishld" ::: "memory")
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#define rmb() asm volatile("dmb ishst" ::: "memory")
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#define wmb() asm volatile("dmb ishst" ::: "memory")
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#define rmb() asm volatile("dmb ishld" ::: "memory")
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#define cpu_relax() asm volatile("yield" ::: "memory")
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#endif
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|
@ -26,7 +26,6 @@ int test__vmlinux_matches_kallsyms(void)
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struct map *kallsyms_map, *vmlinux_map;
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struct machine kallsyms, vmlinux;
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enum map_type type = MAP__FUNCTION;
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struct ref_reloc_sym ref_reloc_sym = { .name = "_stext", };
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u64 mem_start, mem_end;
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/*
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@ -70,14 +69,6 @@ int test__vmlinux_matches_kallsyms(void)
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*/
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kallsyms_map = machine__kernel_map(&kallsyms, type);
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sym = map__find_symbol_by_name(kallsyms_map, ref_reloc_sym.name, NULL);
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if (sym == NULL) {
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pr_debug("dso__find_symbol_by_name ");
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goto out;
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}
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ref_reloc_sym.addr = UM(sym->start);
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/*
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* Step 5:
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*
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@ -89,7 +80,6 @@ int test__vmlinux_matches_kallsyms(void)
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}
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vmlinux_map = machine__kernel_map(&vmlinux, type);
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map__kmap(vmlinux_map)->ref_reloc_sym = &ref_reloc_sym;
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/*
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* Step 6:
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|
@ -470,23 +470,32 @@ static int find_symbol_cb(void *arg, const char *name, char type,
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return 1;
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}
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u64 kallsyms__get_function_start(const char *kallsyms_filename,
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const char *symbol_name)
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{
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struct process_symbol_args args = { .name = symbol_name, };
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if (kallsyms__parse(kallsyms_filename, &args, find_symbol_cb) <= 0)
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return 0;
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return args.start;
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}
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int perf_event__synthesize_kernel_mmap(struct perf_tool *tool,
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perf_event__handler_t process,
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struct machine *machine,
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const char *symbol_name)
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struct machine *machine)
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{
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size_t size;
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const char *filename, *mmap_name;
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char path[PATH_MAX];
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const char *mmap_name;
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char name_buff[PATH_MAX];
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struct map *map;
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struct kmap *kmap;
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int err;
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/*
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* We should get this from /sys/kernel/sections/.text, but till that is
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* available use this, and after it is use this as a fallback for older
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* kernels.
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*/
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struct process_symbol_args args = { .name = symbol_name, };
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union perf_event *event = zalloc((sizeof(event->mmap) +
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machine->id_hdr_size));
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if (event == NULL) {
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@ -502,30 +511,19 @@ int perf_event__synthesize_kernel_mmap(struct perf_tool *tool,
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* see kernel/perf_event.c __perf_event_mmap
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*/
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event->header.misc = PERF_RECORD_MISC_KERNEL;
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filename = "/proc/kallsyms";
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} else {
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event->header.misc = PERF_RECORD_MISC_GUEST_KERNEL;
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if (machine__is_default_guest(machine))
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filename = (char *) symbol_conf.default_guest_kallsyms;
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else {
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sprintf(path, "%s/proc/kallsyms", machine->root_dir);
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filename = path;
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}
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}
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if (kallsyms__parse(filename, &args, find_symbol_cb) <= 0) {
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free(event);
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return -ENOENT;
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}
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map = machine->vmlinux_maps[MAP__FUNCTION];
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kmap = map__kmap(map);
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size = snprintf(event->mmap.filename, sizeof(event->mmap.filename),
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"%s%s", mmap_name, symbol_name) + 1;
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"%s%s", mmap_name, kmap->ref_reloc_sym->name) + 1;
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size = PERF_ALIGN(size, sizeof(u64));
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event->mmap.header.type = PERF_RECORD_MMAP;
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event->mmap.header.size = (sizeof(event->mmap) -
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(sizeof(event->mmap.filename) - size) + machine->id_hdr_size);
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event->mmap.pgoff = args.start;
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event->mmap.pgoff = kmap->ref_reloc_sym->addr;
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event->mmap.start = map->start;
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event->mmap.len = map->end - event->mmap.start;
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event->mmap.pid = machine->pid;
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@ -214,8 +214,7 @@ int perf_event__synthesize_threads(struct perf_tool *tool,
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struct machine *machine, bool mmap_data);
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int perf_event__synthesize_kernel_mmap(struct perf_tool *tool,
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perf_event__handler_t process,
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struct machine *machine,
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const char *symbol_name);
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struct machine *machine);
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int perf_event__synthesize_modules(struct perf_tool *tool,
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perf_event__handler_t process,
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@ -279,4 +278,7 @@ size_t perf_event__fprintf_mmap2(union perf_event *event, FILE *fp);
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size_t perf_event__fprintf_task(union perf_event *event, FILE *fp);
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size_t perf_event__fprintf(union perf_event *event, FILE *fp);
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u64 kallsyms__get_function_start(const char *kallsyms_filename,
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const char *symbol_name);
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#endif /* __PERF_RECORD_H */
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|
6
tools/perf/util/include/asm/hash.h
Normal file
6
tools/perf/util/include/asm/hash.h
Normal file
@ -0,0 +1,6 @@
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#ifndef __ASM_GENERIC_HASH_H
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#define __ASM_GENERIC_HASH_H
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/* Stub */
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#endif /* __ASM_GENERIC_HASH_H */
|
@ -496,19 +496,22 @@ static int symbol__in_kernel(void *arg, const char *name,
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return 1;
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}
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static void machine__get_kallsyms_filename(struct machine *machine, char *buf,
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size_t bufsz)
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{
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if (machine__is_default_guest(machine))
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scnprintf(buf, bufsz, "%s", symbol_conf.default_guest_kallsyms);
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else
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scnprintf(buf, bufsz, "%s/proc/kallsyms", machine->root_dir);
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}
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/* Figure out the start address of kernel map from /proc/kallsyms */
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static u64 machine__get_kernel_start_addr(struct machine *machine)
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{
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const char *filename;
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char path[PATH_MAX];
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char filename[PATH_MAX];
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struct process_args args;
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|
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if (machine__is_default_guest(machine))
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filename = (char *)symbol_conf.default_guest_kallsyms;
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else {
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sprintf(path, "%s/proc/kallsyms", machine->root_dir);
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filename = path;
|
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}
|
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machine__get_kallsyms_filename(machine, filename, PATH_MAX);
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|
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if (symbol__restricted_filename(filename, "/proc/kallsyms"))
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return 0;
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@ -829,9 +832,25 @@ static int machine__create_modules(struct machine *machine)
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return 0;
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}
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|
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const char *ref_reloc_sym_names[] = {"_text", "_stext", NULL};
|
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|
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int machine__create_kernel_maps(struct machine *machine)
|
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{
|
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struct dso *kernel = machine__get_kernel(machine);
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char filename[PATH_MAX];
|
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const char *name;
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u64 addr = 0;
|
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int i;
|
||||
|
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machine__get_kallsyms_filename(machine, filename, PATH_MAX);
|
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|
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for (i = 0; (name = ref_reloc_sym_names[i]) != NULL; i++) {
|
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addr = kallsyms__get_function_start(filename, name);
|
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if (addr)
|
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break;
|
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}
|
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if (!addr)
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return -1;
|
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|
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if (kernel == NULL ||
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__machine__create_kernel_maps(machine, kernel) < 0)
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@ -850,6 +869,13 @@ int machine__create_kernel_maps(struct machine *machine)
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* Now that we have all the maps created, just set the ->end of them:
|
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*/
|
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map_groups__fixup_end(&machine->kmaps);
|
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|
||||
if (maps__set_kallsyms_ref_reloc_sym(machine->vmlinux_maps, name,
|
||||
addr)) {
|
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machine__destroy_kernel_maps(machine);
|
||||
return -1;
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
|
@ -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;
|
||||
|
@ -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)
|
||||
|
@ -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 */
|
||||
|
@ -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);
|
||||
|
@ -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;
|
||||
}
|
||||
|
||||
|
Loading…
Reference in New Issue
Block a user