1 files changed, 1245 insertions, 316 deletions

diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 226f44a2357d..c458c4a371d1 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -1,111 +1,234 @@
 #include "util.h"
 #include "../perf.h"
+#include "sort.h"
 #include "string.h"
 #include "symbol.h"
+#include "thread.h"
 
 #include "debug.h"
 
+#include <asm/bug.h>
 #include <libelf.h>
 #include <gelf.h>
 #include <elf.h>
+#include <limits.h>
+#include <sys/utsname.h>
 
-const char *sym_hist_filter;
+#ifndef NT_GNU_BUILD_ID
+#define NT_GNU_BUILD_ID 3
+#endif
 
 enum dso_origin {
         DSO__ORIG_KERNEL = 0,
         DSO__ORIG_JAVA_JIT,
+        DSO__ORIG_BUILD_ID_CACHE,
         DSO__ORIG_FEDORA,
         DSO__ORIG_UBUNTU,
         DSO__ORIG_BUILDID,
         DSO__ORIG_DSO,
+        DSO__ORIG_KMODULE,
         DSO__ORIG_NOT_FOUND,
 };
 
-static struct symbol *symbol__new(u64 start, u64 len,
-                                  const char *name, unsigned int priv_size,
-                                  u64 obj_start, int v)
+static void dsos__add(struct list_head *head, struct dso *dso);
+static struct map *map__new2(u64 start, struct dso *dso, enum map_type type);
+static int dso__load_kernel_sym(struct dso *self, struct map *map,
+                                symbol_filter_t filter);
+static int vmlinux_path__nr_entries;
+static char **vmlinux_path;
+
+struct symbol_conf symbol_conf = {
+        .exclude_other    = true,
+        .use_modules      = true,
+        .try_vmlinux_path = true,
+};
+
+bool dso__loaded(const struct dso *self, enum map_type type)
 {
-        size_t namelen = strlen(name) + 1;
-        struct symbol *self = calloc(1, priv_size + sizeof(*self) + namelen);
+        return self->loaded & (1 << type);
+}
 
-        if (!self)
-                return NULL;
+bool dso__sorted_by_name(const struct dso *self, enum map_type type)
+{
+        return self->sorted_by_name & (1 << type);
+}
+
+static void dso__set_sorted_by_name(struct dso *self, enum map_type type)
+{
+        self->sorted_by_name |= (1 << type);
+}
+
+bool symbol_type__is_a(char symbol_type, enum map_type map_type)
+{
+        switch (map_type) {
+        case MAP__FUNCTION:
+                return symbol_type == 'T' || symbol_type == 'W';
+        case MAP__VARIABLE:
+                return symbol_type == 'D' || symbol_type == 'd';
+        default:
+                return false;
+        }
+}
 
-        if (v >= 2)
-                printf("new symbol: %016Lx [%08lx]: %s, hist: %p, obj_start: %p\n",
-                        (u64)start, (unsigned long)len, name, self->hist, (void *)(unsigned long)obj_start);
+static void symbols__fixup_end(struct rb_root *self)
+{
+        struct rb_node *nd, *prevnd = rb_first(self);
+        struct symbol *curr, *prev;
 
-        self->obj_start= obj_start;
-        self->hist = NULL;
-        self->hist_sum = 0;
+        if (prevnd == NULL)
+                return;
 
-        if (sym_hist_filter && !strcmp(name, sym_hist_filter))
-                self->hist = calloc(sizeof(u64), len);
+        curr = rb_entry(prevnd, struct symbol, rb_node);
 
-        if (priv_size) {
-                memset(self, 0, priv_size);
-                self = ((void *)self) + priv_size;
+        for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
+                prev = curr;
+                curr = rb_entry(nd, struct symbol, rb_node);
+
+                if (prev->end == prev->start)
+                        prev->end = curr->start - 1;
         }
+
+        /* Last entry */
+        if (curr->end == curr->start)
+                curr->end = roundup(curr->start, 4096);
+}
+
+static void __map_groups__fixup_end(struct map_groups *self, enum map_type type)
+{
+        struct map *prev, *curr;
+        struct rb_node *nd, *prevnd = rb_first(&self->maps[type]);
+
+        if (prevnd == NULL)
+                return;
+
+        curr = rb_entry(prevnd, struct map, rb_node);
+
+        for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
+                prev = curr;
+                curr = rb_entry(nd, struct map, rb_node);
+                prev->end = curr->start - 1;
+        }
+
+        /*
+         * We still haven't the actual symbols, so guess the
+         * last map final address.
+         */
+        curr->end = ~0UL;
+}
+
+static void map_groups__fixup_end(struct map_groups *self)
+{
+        int i;
+        for (i = 0; i < MAP__NR_TYPES; ++i)
+                __map_groups__fixup_end(self, i);
+}
+
+static struct symbol *symbol__new(u64 start, u64 len, const char *name)
+{
+        size_t namelen = strlen(name) + 1;
+        struct symbol *self = zalloc(symbol_conf.priv_size +
+                                     sizeof(*self) + namelen);
+        if (self == NULL)
+                return NULL;
+
+        if (symbol_conf.priv_size)
+                self = ((void *)self) + symbol_conf.priv_size;
+
         self->start = start;
         self->end   = len ? start + len - 1 : start;
+
+        pr_debug4("%s: %s %#Lx-%#Lx\n", __func__, name, start, self->end);
+
         memcpy(self->name, name, namelen);
 
         return self;
 }
 
-static void symbol__delete(struct symbol *self, unsigned int priv_size)
+void symbol__delete(struct symbol *self)
 {
-        free(((void *)self) - priv_size);
+        free(((void *)self) - symbol_conf.priv_size);
 }
 
 static size_t symbol__fprintf(struct symbol *self, FILE *fp)
 {
-        if (!self->module)
-                return fprintf(fp, " %llx-%llx %s\n",
+        return fprintf(fp, " %llx-%llx %s\n",
                        self->start, self->end, self->name);
-        else
-                return fprintf(fp, " %llx-%llx %s \t[%s]\n",
-                       self->start, self->end, self->name, self->module->name);
 }
 
-struct dso *dso__new(const char *name, unsigned int sym_priv_size)
+void dso__set_long_name(struct dso *self, char *name)
 {
-        struct dso *self = malloc(sizeof(*self) + strlen(name) + 1);
+        if (name == NULL)
+                return;
+        self->long_name = name;
+        self->long_name_len = strlen(name);
+}
+
+static void dso__set_short_name(struct dso *self, const char *name)
+{
+        if (name == NULL)
+                return;
+        self->short_name = name;
+        self->short_name_len = strlen(name);
+}
+
+static void dso__set_basename(struct dso *self)
+{
+        dso__set_short_name(self, basename(self->long_name));
+}
+
+struct dso *dso__new(const char *name)
+{
+        struct dso *self = zalloc(sizeof(*self) + strlen(name) + 1);
 
         if (self != NULL) {
+                int i;
                 strcpy(self->name, name);
-                self->syms = RB_ROOT;
-                self->sym_priv_size = sym_priv_size;
-                self->find_symbol = dso__find_symbol;
+                dso__set_long_name(self, self->name);
+                dso__set_short_name(self, self->name);
+                for (i = 0; i < MAP__NR_TYPES; ++i)
+                        self->symbols[i] = self->symbol_names[i] = RB_ROOT;
                 self->slen_calculated = 0;
                 self->origin = DSO__ORIG_NOT_FOUND;
+                self->loaded = 0;
+                self->sorted_by_name = 0;
+                self->has_build_id = 0;
         }
 
         return self;
 }
 
-static void dso__delete_symbols(struct dso *self)
+static void symbols__delete(struct rb_root *self)
 {
         struct symbol *pos;
-        struct rb_node *next = rb_first(&self->syms);
+        struct rb_node *next = rb_first(self);
 
         while (next) {
                 pos = rb_entry(next, struct symbol, rb_node);
                 next = rb_next(&pos->rb_node);
-                rb_erase(&pos->rb_node, &self->syms);
-                symbol__delete(pos, self->sym_priv_size);
+                rb_erase(&pos->rb_node, self);
+                symbol__delete(pos);
         }
 }
 
 void dso__delete(struct dso *self)
 {
-        dso__delete_symbols(self);
+        int i;
+        for (i = 0; i < MAP__NR_TYPES; ++i)
+                symbols__delete(&self->symbols[i]);
+        if (self->long_name != self->name)
+                free(self->long_name);
         free(self);
 }
 
-static void dso__insert_symbol(struct dso *self, struct symbol *sym)
+void dso__set_build_id(struct dso *self, void *build_id)
 {
-        struct rb_node **p = &self->syms.rb_node;
+        memcpy(self->build_id, build_id, sizeof(self->build_id));
+        self->has_build_id = 1;
+}
+
+static void symbols__insert(struct rb_root *self, struct symbol *sym)
+{
+        struct rb_node **p = &self->rb_node;
         struct rb_node *parent = NULL;
         const u64 ip = sym->start;
         struct symbol *s;
@@ -119,17 +242,17 @@ static void dso__insert_symbol(struct dso *self, struct symbol *sym)
                         p = &(*p)->rb_right;
         }
         rb_link_node(&sym->rb_node, parent, p);
-        rb_insert_color(&sym->rb_node, &self->syms);
+        rb_insert_color(&sym->rb_node, self);
 }
 
-struct symbol *dso__find_symbol(struct dso *self, u64 ip)
+static struct symbol *symbols__find(struct rb_root *self, u64 ip)
 {
         struct rb_node *n;
 
         if (self == NULL)
                 return NULL;
 
-        n = self->syms.rb_node;
+        n = self->rb_node;
 
         while (n) {
                 struct symbol *s = rb_entry(n, struct symbol, rb_node);
@@ -145,12 +268,120 @@ struct symbol *dso__find_symbol(struct dso *self, u64 ip)
         return NULL;
 }
 
-size_t dso__fprintf(struct dso *self, FILE *fp)
+struct symbol_name_rb_node {
+        struct rb_node  rb_node;
+        struct symbol   sym;
+};
+
+static void symbols__insert_by_name(struct rb_root *self, struct symbol *sym)
+{
+        struct rb_node **p = &self->rb_node;
+        struct rb_node *parent = NULL;
+        struct symbol_name_rb_node *symn = ((void *)sym) - sizeof(*parent), *s;
+
+        while (*p != NULL) {
+                parent = *p;
+                s = rb_entry(parent, struct symbol_name_rb_node, rb_node);
+                if (strcmp(sym->name, s->sym.name) < 0)
+                        p = &(*p)->rb_left;
+                else
+                        p = &(*p)->rb_right;
+        }
+        rb_link_node(&symn->rb_node, parent, p);
+        rb_insert_color(&symn->rb_node, self);
+}
+
+static void symbols__sort_by_name(struct rb_root *self, struct rb_root *source)
+{
+        struct rb_node *nd;
+
+        for (nd = rb_first(source); nd; nd = rb_next(nd)) {
+                struct symbol *pos = rb_entry(nd, struct symbol, rb_node);
+                symbols__insert_by_name(self, pos);
+        }
+}
+
+static struct symbol *symbols__find_by_name(struct rb_root *self, const char *name)
+{
+        struct rb_node *n;
+
+        if (self == NULL)
+                return NULL;
+
+        n = self->rb_node;
+
+        while (n) {
+                struct symbol_name_rb_node *s;
+                int cmp;
+
+                s = rb_entry(n, struct symbol_name_rb_node, rb_node);
+                cmp = strcmp(name, s->sym.name);
+
+                if (cmp < 0)
+                        n = n->rb_left;
+                else if (cmp > 0)
+                        n = n->rb_right;
+                else
+                        return &s->sym;
+        }
+
+        return NULL;
+}
+
+struct symbol *dso__find_symbol(struct dso *self,
+                                enum map_type type, u64 addr)
+{
+        return symbols__find(&self->symbols[type], addr);
+}
+
+struct symbol *dso__find_symbol_by_name(struct dso *self, enum map_type type,
+                                        const char *name)
+{
+        return symbols__find_by_name(&self->symbol_names[type], name);
+}
+
+void dso__sort_by_name(struct dso *self, enum map_type type)
+{
+        dso__set_sorted_by_name(self, type);
+        return symbols__sort_by_name(&self->symbol_names[type],
+                                     &self->symbols[type]);
+}
+
+int build_id__sprintf(const u8 *self, int len, char *bf)
+{
+        char *bid = bf;
+        const u8 *raw = self;
+        int i;
+
+        for (i = 0; i < len; ++i) {
+                sprintf(bid, "%02x", *raw);
+                ++raw;
+                bid += 2;
+        }
+
+        return raw - self;
+}
+
+size_t dso__fprintf_buildid(struct dso *self, FILE *fp)
 {
-        size_t ret = fprintf(fp, "dso: %s\n", self->name);
+        char sbuild_id[BUILD_ID_SIZE * 2 + 1];
+
+        build_id__sprintf(self->build_id, sizeof(self->build_id), sbuild_id);
+        return fprintf(fp, "%s", sbuild_id);
+}
 
+size_t dso__fprintf(struct dso *self, enum map_type type, FILE *fp)
+{
         struct rb_node *nd;
-        for (nd = rb_first(&self->syms); nd; nd = rb_next(nd)) {
+        size_t ret = fprintf(fp, "dso: %s (", self->short_name);
+
+        if (self->short_name != self->long_name)
+                ret += fprintf(fp, "%s, ", self->long_name);
+        ret += fprintf(fp, "%s, %sloaded, ", map_type__name[type],
+                       self->loaded ? "" : "NOT ");
+        ret += dso__fprintf_buildid(self, fp);
+        ret += fprintf(fp, ")\n");
+        for (nd = rb_first(&self->symbols[type]); nd; nd = rb_next(nd)) {
                 struct symbol *pos = rb_entry(nd, struct symbol, rb_node);
                 ret += symbol__fprintf(pos, fp);
         }
@@ -158,22 +389,23 @@ size_t dso__fprintf(struct dso *self, FILE *fp)
         return ret;
 }
 
-static int dso__load_kallsyms(struct dso *self, symbol_filter_t filter, int v)
+int kallsyms__parse(const char *filename, void *arg,
+                    int (*process_symbol)(void *arg, const char *name,
+                                                     char type, u64 start))
 {
-        struct rb_node *nd, *prevnd;
         char *line = NULL;
         size_t n;
-        FILE *file = fopen("/proc/kallsyms", "r");
-        int count = 0;
+        int err = 0;
+        FILE *file = fopen(filename, "r");
 
         if (file == NULL)
                 goto out_failure;
 
         while (!feof(file)) {
                 u64 start;
-                struct symbol *sym;
                 int line_len, len;
                 char symbol_type;
+                char *symbol_name;
 
                 line_len = getline(&line, &n, file);
                 if (line_len < 0)
@@ -191,64 +423,168 @@ static int dso__load_kallsyms(struct dso *self, symbol_filter_t filter, int v)
                         continue;
 
                 symbol_type = toupper(line[len]);
-                /*
-                 * We're interested only in code ('T'ext)
-                 */
-                if (symbol_type != 'T' && symbol_type != 'W')
-                        continue;
-                /*
-                 * Well fix up the end later, when we have all sorted.
-                 */
-                sym = symbol__new(start, 0xdead, line + len + 2,
-                                  self->sym_priv_size, 0, v);
+                symbol_name = line + len + 2;
 
-                if (sym == NULL)
-                        goto out_delete_line;
-
-                if (filter && filter(self, sym))
-                        symbol__delete(sym, self->sym_priv_size);
-                else {
-                        dso__insert_symbol(self, sym);
-                        count++;
-                }
+                err = process_symbol(arg, symbol_name, symbol_type, start);
+                if (err)
+                        break;
         }
 
+        free(line);
+        fclose(file);
+        return err;
+
+out_failure:
+        return -1;
+}
+
+struct process_kallsyms_args {
+        struct map *map;
+        struct dso *dso;
+};
+
+static int map__process_kallsym_symbol(void *arg, const char *name,
+                                       char type, u64 start)
+{
+        struct symbol *sym;
+        struct process_kallsyms_args *a = arg;
+        struct rb_root *root = &a->dso->symbols[a->map->type];
+
+        if (!symbol_type__is_a(type, a->map->type))
+                return 0;
+
         /*
-         * Now that we have all sorted out, just set the ->end of all
-         * symbols
+         * Will fix up the end later, when we have all symbols sorted.
          */
-        prevnd = rb_first(&self->syms);
+        sym = symbol__new(start, 0, name);
 
-        if (prevnd == NULL)
-                goto out_delete_line;
+        if (sym == NULL)
+                return -ENOMEM;
+        /*
+         * We will pass the symbols to the filter later, in
+         * map__split_kallsyms, when we have split the maps per module
+         */
+        symbols__insert(root, sym);
+        return 0;
+}
 
-        for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
-                struct symbol *prev = rb_entry(prevnd, struct symbol, rb_node),
-                              *curr = rb_entry(nd, struct symbol, rb_node);
+/*
+ * Loads the function entries in /proc/kallsyms into kernel_map->dso,
+ * so that we can in the next step set the symbol ->end address and then
+ * call kernel_maps__split_kallsyms.
+ */
+static int dso__load_all_kallsyms(struct dso *self, const char *filename,
+                                  struct map *map)
+{
+        struct process_kallsyms_args args = { .map = map, .dso = self, };
+        return kallsyms__parse(filename, &args, map__process_kallsym_symbol);
+}
 
-                prev->end = curr->start - 1;
-                prevnd = nd;
-        }
+/*
+ * Split the symbols into maps, making sure there are no overlaps, i.e. the
+ * 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 *self, struct map *map,
+                               symbol_filter_t filter)
+{
+        struct map_groups *kmaps = map__kmap(map)->kmaps;
+        struct map *curr_map = map;
+        struct symbol *pos;
+        int count = 0;
+        struct rb_root *root = &self->symbols[map->type];
+        struct rb_node *next = rb_first(root);
+        int kernel_range = 0;
 
-        free(line);
-        fclose(file);
+        while (next) {
+                char *module;
+
+                pos = rb_entry(next, struct symbol, rb_node);
+                next = rb_next(&pos->rb_node);
+
+                module = strchr(pos->name, '\t');
+                if (module) {
+                        if (!symbol_conf.use_modules)
+                                goto discard_symbol;
+
+                        *module++ = '\0';
+
+                        if (strcmp(curr_map->dso->short_name, module)) {
+                                curr_map = map_groups__find_by_name(kmaps, map->type, module);
+                                if (curr_map == NULL) {
+                                        pr_debug("/proc/{kallsyms,modules} "
+                                                 "inconsistency while looking "
+                                                 "for \"%s\" module!\n", module);
+                                        return -1;
+                                }
+
+                                if (curr_map->dso->loaded)
+                                        goto discard_symbol;
+                        }
+                        /*
+                         * So that we look just like we get from .ko files,
+                         * i.e. not prelinked, relative to map->start.
+                         */
+                        pos->start = curr_map->map_ip(curr_map, pos->start);
+                        pos->end   = curr_map->map_ip(curr_map, pos->end);
+                } else if (curr_map != map) {
+                        char dso_name[PATH_MAX];
+                        struct dso *dso;
+
+                        snprintf(dso_name, sizeof(dso_name), "[kernel].%d",
+                                 kernel_range++);
+
+                        dso = dso__new(dso_name);
+                        if (dso == NULL)
+                                return -1;
+
+                        curr_map = map__new2(pos->start, dso, map->type);
+                        if (curr_map == NULL) {
+                                dso__delete(dso);
+                                return -1;
+                        }
+
+                        curr_map->map_ip = curr_map->unmap_ip = identity__map_ip;
+                        map_groups__insert(kmaps, curr_map);
+                        ++kernel_range;
+                }
+
+                if (filter && filter(curr_map, pos)) {
+discard_symbol:         rb_erase(&pos->rb_node, root);
+                        symbol__delete(pos);
+                } else {
+                        if (curr_map != map) {
+                                rb_erase(&pos->rb_node, root);
+                                symbols__insert(&curr_map->dso->symbols[curr_map->type], pos);
+                        }
+                        count++;
+                }
+        }
 
         return count;
+}
 
-out_delete_line:
-        free(line);
-out_failure:
-        return -1;
+int dso__load_kallsyms(struct dso *self, const char *filename,
+                       struct map *map, symbol_filter_t filter)
+{
+        if (dso__load_all_kallsyms(self, filename, map) < 0)
+                return -1;
+
+        symbols__fixup_end(&self->symbols[map->type]);
+        self->origin = DSO__ORIG_KERNEL;
+
+        return dso__split_kallsyms(self, map, filter);
 }
 
-static int dso__load_perf_map(struct dso *self, symbol_filter_t filter, int v)
+static int dso__load_perf_map(struct dso *self, struct map *map,
+                              symbol_filter_t filter)
 {
         char *line = NULL;
         size_t n;
         FILE *file;
         int nr_syms = 0;
 
-        file = fopen(self->name, "r");
+        file = fopen(self->long_name, "r");
         if (file == NULL)
                 goto out_failure;
 
@@ -278,16 +614,15 @@ static int dso__load_perf_map(struct dso *self, symbol_filter_t filter, int v)
                 if (len + 2 >= line_len)
                         continue;
 
-                sym = symbol__new(start, size, line + len,
-                                  self->sym_priv_size, start, v);
+                sym = symbol__new(start, size, line + len);
 
                 if (sym == NULL)
                         goto out_delete_line;
 
-                if (filter && filter(self, sym))
-                        symbol__delete(sym, self->sym_priv_size);
+                if (filter && filter(map, sym))
+                        symbol__delete(sym);
                 else {
-                        dso__insert_symbol(self, sym);
+                        symbols__insert(&self->symbols[map->type], sym);
                         nr_syms++;
                 }
         }
@@ -327,6 +662,13 @@ static inline int elf_sym__is_function(const GElf_Sym *sym)
                sym->st_shndx != SHN_UNDEF;
 }
 
+static inline bool elf_sym__is_object(const GElf_Sym *sym)
+{
+        return elf_sym__type(sym) == STT_OBJECT &&
+                sym->st_name != 0 &&
+                sym->st_shndx != SHN_UNDEF;
+}
+
 static inline int elf_sym__is_label(const GElf_Sym *sym)
 {
         return elf_sym__type(sym) == STT_NOTYPE &&
@@ -347,6 +689,12 @@ static inline int elf_sec__is_text(const GElf_Shdr *shdr,
         return strstr(elf_sec__name(shdr, secstrs), "text") != NULL;
 }
 
+static inline bool elf_sec__is_data(const GElf_Shdr *shdr,
+                                    const Elf_Data *secstrs)
+{
+        return strstr(elf_sec__name(shdr, secstrs), "data") != NULL;
+}
+
 static inline const char *elf_sym__name(const GElf_Sym *sym,
                                         const Elf_Data *symstrs)
 {
@@ -393,7 +741,8 @@ static Elf_Scn *elf_section_by_name(Elf *elf, GElf_Ehdr *ep,
  * And always look at the original dso, not at debuginfo packages, that
  * have the PLT data stripped out (shdr_rel_plt.sh_type == SHT_NOBITS).
  */
-static int dso__synthesize_plt_symbols(struct  dso *self, int v)
+static int dso__synthesize_plt_symbols(struct  dso *self, struct map *map,
+                                       symbol_filter_t filter)
 {
         uint32_t nr_rel_entries, idx;
         GElf_Sym sym;
@@ -409,7 +758,7 @@ static int dso__synthesize_plt_symbols(struct  dso *self, int v)
         Elf *elf;
         int nr = 0, symidx, fd, err = 0;
 
-        fd = open(self->name, O_RDONLY);
+        fd = open(self->long_name, O_RDONLY);
         if (fd < 0)
                 goto out;
 
@@ -477,12 +826,16 @@ static int dso__synthesize_plt_symbols(struct  dso *self, int v)
                                  "%s@plt", elf_sym__name(&sym, symstrs));
 
                         f = symbol__new(plt_offset, shdr_plt.sh_entsize,
-                                        sympltname, self->sym_priv_size, 0, v);
+                                        sympltname);
                         if (!f)
                                 goto out_elf_end;
 
-                        dso__insert_symbol(self, f);
-                        ++nr;
+                        if (filter && filter(map, f))
+                                symbol__delete(f);
+                        else {
+                                symbols__insert(&self->symbols[map->type], f);
+                                ++nr;
+                        }
                 }
         } else if (shdr_rel_plt.sh_type == SHT_REL) {
                 GElf_Rel pos_mem, *pos;
@@ -495,12 +848,16 @@ static int dso__synthesize_plt_symbols(struct  dso *self, int v)
                                  "%s@plt", elf_sym__name(&sym, symstrs));
 
                         f = symbol__new(plt_offset, shdr_plt.sh_entsize,
-                                        sympltname, self->sym_priv_size, 0, v);
+                                        sympltname);
                         if (!f)
                                 goto out_elf_end;
 
-                        dso__insert_symbol(self, f);
-                        ++nr;
+                        if (filter && filter(map, f))
+                                symbol__delete(f);
+                        else {
+                                symbols__insert(&self->symbols[map->type], f);
+                                ++nr;
+                        }
                 }
         }
 
@@ -513,14 +870,41 @@ out_close:
         if (err == 0)
                 return nr;
 out:
-        fprintf(stderr, "%s: problems reading %s PLT info.\n",
-                __func__, self->name);
+        pr_warning("%s: problems reading %s PLT info.\n",
+                   __func__, self->long_name);
         return 0;
 }
 
-static int dso__load_sym(struct dso *self, int fd, const char *name,
-                         symbol_filter_t filter, int v, struct module *mod)
+static bool elf_sym__is_a(GElf_Sym *self, enum map_type type)
 {
+        switch (type) {
+        case MAP__FUNCTION:
+                return elf_sym__is_function(self);
+        case MAP__VARIABLE:
+                return elf_sym__is_object(self);
+        default:
+                return false;
+        }
+}
+
+static bool elf_sec__is_a(GElf_Shdr *self, Elf_Data *secstrs, enum map_type type)
+{
+        switch (type) {
+        case MAP__FUNCTION:
+                return elf_sec__is_text(self, secstrs);
+        case MAP__VARIABLE:
+                return elf_sec__is_data(self, secstrs);
+        default:
+                return false;
+        }
+}
+
+static int dso__load_sym(struct dso *self, struct map *map, const char *name,
+                         int fd, symbol_filter_t filter, int kmodule)
+{
+        struct kmap *kmap = self->kernel ? map__kmap(map) : NULL;
+        struct map *curr_map = map;
+        struct dso *curr_dso = self;
         Elf_Data *symstrs, *secstrs;
         uint32_t nr_syms;
         int err = -1;
@@ -531,19 +915,16 @@ static int dso__load_sym(struct dso *self, int fd, const char *name,
         GElf_Sym sym;
         Elf_Scn *sec, *sec_strndx;
         Elf *elf;
-        int nr = 0, kernel = !strcmp("[kernel]", self->name);
+        int nr = 0;
 
         elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
         if (elf == NULL) {
-                if (v)
-                        fprintf(stderr, "%s: cannot read %s ELF file.\n",
-                                __func__, name);
+                pr_err("%s: cannot read %s ELF file.\n", __func__, name);
                 goto out_close;
         }
 
         if (gelf_getehdr(elf, &ehdr) == NULL) {
-                if (v)
-                        fprintf(stderr, "%s: cannot get elf header.\n", __func__);
+                pr_err("%s: cannot get elf header.\n", __func__);
                 goto out_elf_end;
         }
 
@@ -577,7 +958,7 @@ static int dso__load_sym(struct dso *self, int fd, const char *name,
         nr_syms = shdr.sh_size / shdr.sh_entsize;
 
         memset(&sym, 0, sizeof(sym));
-        if (!kernel) {
+        if (!self->kernel) {
                 self->adjust_symbols = (ehdr.e_type == ET_EXEC ||
                                 elf_section_by_name(elf, &ehdr, &shdr,
                                                      ".gnu.prelink_undo",
@@ -586,14 +967,16 @@ static int dso__load_sym(struct dso *self, int fd, const char *name,
 
         elf_symtab__for_each_symbol(syms, nr_syms, idx, sym) {
                 struct symbol *f;
-                const char *elf_name;
-                char *demangled;
-                u64 obj_start;
-                struct section *section = NULL;
+                const char *elf_name = elf_sym__name(&sym, symstrs);
+                char *demangled = NULL;
                 int is_label = elf_sym__is_label(&sym);
                 const char *section_name;
 
-                if (!is_label && !elf_sym__is_function(&sym))
+                if (kmap && kmap->ref_reloc_sym && kmap->ref_reloc_sym->name &&
+                    strcmp(elf_name, kmap->ref_reloc_sym->name) == 0)
+                        kmap->ref_reloc_sym->unrelocated_addr = sym.st_value;
+
+                if (!is_label && !elf_sym__is_a(&sym, map->type))
                         continue;
 
                 sec = elf_getscn(elf, sym.st_shndx);
@@ -602,55 +985,98 @@ static int dso__load_sym(struct dso *self, int fd, const char *name,
 
                 gelf_getshdr(sec, &shdr);
 
-                if (is_label && !elf_sec__is_text(&shdr, secstrs))
+                if (is_label && !elf_sec__is_a(&shdr, secstrs, map->type))
                         continue;
 
                 section_name = elf_sec__name(&shdr, secstrs);
-                obj_start = sym.st_value;
 
-                if (self->adjust_symbols) {
-                        if (v >= 2)
-                                printf("adjusting symbol: st_value: %Lx sh_addr: %Lx sh_offset: %Lx\n",
-                                        (u64)sym.st_value, (u64)shdr.sh_addr, (u64)shdr.sh_offset);
+                if (self->kernel || kmodule) {
+                        char dso_name[PATH_MAX];
 
-                        sym.st_value -= shdr.sh_addr - shdr.sh_offset;
-                }
+                        if (strcmp(section_name,
+                                   (curr_dso->short_name +
+                                    self->short_name_len)) == 0)
+                                goto new_symbol;
 
-                if (mod) {
-                        section = mod->sections->find_section(mod->sections, section_name);
-                        if (section)
-                                sym.st_value += section->vma;
-                        else {
-                                fprintf(stderr, "dso__load_sym() module %s lookup of %s failed\n",
-                                        mod->name, section_name);
-                                goto out_elf_end;
+                        if (strcmp(section_name, ".text") == 0) {
+                                curr_map = map;
+                                curr_dso = self;
+                                goto new_symbol;
                         }
+
+                        snprintf(dso_name, sizeof(dso_name),
+                                 "%s%s", self->short_name, section_name);
+
+                        curr_map = map_groups__find_by_name(kmap->kmaps, map->type, dso_name);
+                        if (curr_map == NULL) {
+                                u64 start = sym.st_value;
+
+                                if (kmodule)
+                                        start += map->start + shdr.sh_offset;
+
+                                curr_dso = dso__new(dso_name);
+                                if (curr_dso == NULL)
+                                        goto out_elf_end;
+                                curr_map = map__new2(start, curr_dso,
+                                                     map->type);
+                                if (curr_map == NULL) {
+                                        dso__delete(curr_dso);
+                                        goto out_elf_end;
+                                }
+                                curr_map->map_ip = identity__map_ip;
+                                curr_map->unmap_ip = identity__map_ip;
+                                curr_dso->origin = DSO__ORIG_KERNEL;
+                                map_groups__insert(kmap->kmaps, curr_map);
+                                dsos__add(&dsos__kernel, curr_dso);
+                                dso__set_loaded(curr_dso, map->type);
+                        } else
+                                curr_dso = curr_map->dso;
+
+                        goto new_symbol;
+                }
+
+                if (curr_dso->adjust_symbols) {
+                        pr_debug4("%s: adjusting symbol: st_value: %#Lx "
+                                  "sh_addr: %#Lx sh_offset: %#Lx\n", __func__,
+                                  (u64)sym.st_value, (u64)shdr.sh_addr,
+                                  (u64)shdr.sh_offset);
+                        sym.st_value -= shdr.sh_addr - shdr.sh_offset;
                 }
                 /*
                  * 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
                  * to it...
                  */
-                elf_name = elf_sym__name(&sym, symstrs);
                 demangled = bfd_demangle(NULL, elf_name, DMGL_PARAMS | DMGL_ANSI);
                 if (demangled != NULL)
                         elf_name = demangled;
-
-                f = symbol__new(sym.st_value, sym.st_size, elf_name,
-                                self->sym_priv_size, obj_start, v);
+new_symbol:
+                f = symbol__new(sym.st_value, sym.st_size, elf_name);
                 free(demangled);
                 if (!f)
                         goto out_elf_end;
 
-                if (filter && filter(self, f))
-                        symbol__delete(f, self->sym_priv_size);
+                if (filter && filter(curr_map, f))
+                        symbol__delete(f);
                 else {
-                        f->module = mod;
-                        dso__insert_symbol(self, f);
+                        symbols__insert(&curr_dso->symbols[curr_map->type], f);
                         nr++;
                 }
         }
 
+        /*
+         * For misannotated, zeroed, ASM function sizes.
+         */
+        if (nr > 0) {
+                symbols__fixup_end(&self->symbols[map->type]);
+                if (kmap) {
+                        /*
+                         * We need to fixup this here too because we create new
+                         * maps here, for things like vsyscall sections.
+                         */
+                        __map_groups__fixup_end(kmap->kmaps, map->type);
+                }
+        }
         err = nr;
 out_elf_end:
         elf_end(elf);
@@ -658,63 +1084,157 @@ out_close:
         return err;
 }
 
-#define BUILD_ID_SIZE 128
+static bool dso__build_id_equal(const struct dso *self, u8 *build_id)
+{
+        return memcmp(self->build_id, build_id, sizeof(self->build_id)) == 0;
+}
 
-static char *dso__read_build_id(struct dso *self, int v)
+static bool __dsos__read_build_ids(struct list_head *head, bool with_hits)
 {
-        int i;
+        bool have_build_id = false;
+        struct dso *pos;
+
+        list_for_each_entry(pos, head, node) {
+                if (with_hits && !pos->hit)
+                        continue;
+                if (filename__read_build_id(pos->long_name, pos->build_id,
+                                            sizeof(pos->build_id)) > 0) {
+                        have_build_id     = true;
+                        pos->has_build_id = true;
+                }
+        }
+
+        return have_build_id;
+}
+
+bool dsos__read_build_ids(bool with_hits)
+{
+        bool kbuildids = __dsos__read_build_ids(&dsos__kernel, with_hits),
+             ubuildids = __dsos__read_build_ids(&dsos__user, with_hits);
+        return kbuildids || ubuildids;
+}
+
+/*
+ * Align offset to 4 bytes as needed for note name and descriptor data.
+ */
+#define NOTE_ALIGN(n) (((n) + 3) & -4U)
+
+int filename__read_build_id(const char *filename, void *bf, size_t size)
+{
+        int fd, err = -1;
         GElf_Ehdr ehdr;
         GElf_Shdr shdr;
-        Elf_Data *build_id_data;
+        Elf_Data *data;
         Elf_Scn *sec;
-        char *build_id = NULL, *bid;
-        unsigned char *raw;
+        Elf_Kind ek;
+        void *ptr;
         Elf *elf;
-        int fd = open(self->name, O_RDONLY);
 
+        if (size < BUILD_ID_SIZE)
+                goto out;
+
+        fd = open(filename, O_RDONLY);
         if (fd < 0)
                 goto out;
 
         elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
         if (elf == NULL) {
-                if (v)
-                        fprintf(stderr, "%s: cannot read %s ELF file.\n",
-                                __func__, self->name);
+                pr_debug2("%s: cannot read %s ELF file.\n", __func__, filename);
                 goto out_close;
         }
 
+        ek = elf_kind(elf);
+        if (ek != ELF_K_ELF)
+                goto out_elf_end;
+
         if (gelf_getehdr(elf, &ehdr) == NULL) {
-                if (v)
-                        fprintf(stderr, "%s: cannot get elf header.\n", __func__);
+                pr_err("%s: cannot get elf header.\n", __func__);
                 goto out_elf_end;
         }
 
-        sec = elf_section_by_name(elf, &ehdr, &shdr, ".note.gnu.build-id", NULL);
-        if (sec == NULL)
-                goto out_elf_end;
+        sec = elf_section_by_name(elf, &ehdr, &shdr,
+                                  ".note.gnu.build-id", NULL);
+        if (sec == NULL) {
+                sec = elf_section_by_name(elf, &ehdr, &shdr,
+                                          ".notes", NULL);
+                if (sec == NULL)
+                        goto out_elf_end;
+        }
 
-        build_id_data = elf_getdata(sec, NULL);
-        if (build_id_data == NULL)
+        data = elf_getdata(sec, NULL);
+        if (data == NULL)
                 goto out_elf_end;
-        build_id = malloc(BUILD_ID_SIZE);
-        if (build_id == NULL)
-                goto out_elf_end;
-        raw = build_id_data->d_buf + 16;
-        bid = build_id;
 
-        for (i = 0; i < 20; ++i) {
-                sprintf(bid, "%02x", *raw);
-                ++raw;
-                bid += 2;
+        ptr = data->d_buf;
+        while (ptr < (data->d_buf + data->d_size)) {
+                GElf_Nhdr *nhdr = ptr;
+                int namesz = NOTE_ALIGN(nhdr->n_namesz),
+                    descsz = NOTE_ALIGN(nhdr->n_descsz);
+                const char *name;
+
+                ptr += sizeof(*nhdr);
+                name = ptr;
+                ptr += namesz;
+                if (nhdr->n_type == NT_GNU_BUILD_ID &&
+                    nhdr->n_namesz == sizeof("GNU")) {
+                        if (memcmp(name, "GNU", sizeof("GNU")) == 0) {
+                                memcpy(bf, ptr, BUILD_ID_SIZE);
+                                err = BUILD_ID_SIZE;
+                                break;
+                        }
+                }
+                ptr += descsz;
         }
-        if (v >= 2)
-                printf("%s(%s): %s\n", __func__, self->name, build_id);
 out_elf_end:
         elf_end(elf);
 out_close:
         close(fd);
 out:
-        return build_id;
+        return err;
+}
+
+int sysfs__read_build_id(const char *filename, void *build_id, size_t size)
+{
+        int fd, err = -1;
+
+        if (size < BUILD_ID_SIZE)
+                goto out;
+
+        fd = open(filename, O_RDONLY);
+        if (fd < 0)
+                goto out;
+
+        while (1) {
+                char bf[BUFSIZ];
+                GElf_Nhdr nhdr;
+                int namesz, descsz;
+
+                if (read(fd, &nhdr, sizeof(nhdr)) != sizeof(nhdr))
+                        break;
+
+                namesz = NOTE_ALIGN(nhdr.n_namesz);
+                descsz = NOTE_ALIGN(nhdr.n_descsz);
+                if (nhdr.n_type == NT_GNU_BUILD_ID &&
+                    nhdr.n_namesz == sizeof("GNU")) {
+                        if (read(fd, bf, namesz) != namesz)
+                                break;
+                        if (memcmp(bf, "GNU", sizeof("GNU")) == 0) {
+                                if (read(fd, build_id,
+                                    BUILD_ID_SIZE) == BUILD_ID_SIZE) {
+                                        err = 0;
+                                        break;
+                                }
+                        } else if (read(fd, bf, descsz) != descsz)
+                                break;
+                } else {
+                        int n = namesz + descsz;
+                        if (read(fd, bf, n) != n)
+                                break;
+                }
+        }
+        close(fd);
+out:
+        return err;
 }
 
 char dso__symtab_origin(const struct dso *self)
@@ -722,10 +1242,12 @@ char dso__symtab_origin(const struct dso *self)
         static const char origin[] = {
                 [DSO__ORIG_KERNEL] =   'k',
                 [DSO__ORIG_JAVA_JIT] = 'j',
+                [DSO__ORIG_BUILD_ID_CACHE] = 'B',
                 [DSO__ORIG_FEDORA] =   'f',
                 [DSO__ORIG_UBUNTU] =   'u',
                 [DSO__ORIG_BUILDID] =  'b',
                 [DSO__ORIG_DSO] =      'd',
+                [DSO__ORIG_KMODULE] =  'K',
         };
 
         if (self == NULL || self->origin == DSO__ORIG_NOT_FOUND)
@@ -733,60 +1255,90 @@ char dso__symtab_origin(const struct dso *self)
         return origin[self->origin];
 }
 
-int dso__load(struct dso *self, symbol_filter_t filter, int v)
+int dso__load(struct dso *self, struct map *map, symbol_filter_t filter)
 {
         int size = PATH_MAX;
-        char *name = malloc(size), *build_id = NULL;
+        char *name;
+        u8 build_id[BUILD_ID_SIZE];
+        char build_id_hex[BUILD_ID_SIZE * 2 + 1];
         int ret = -1;
         int fd;
 
+        dso__set_loaded(self, map->type);
+
+        if (self->kernel)
+                return dso__load_kernel_sym(self, map, filter);
+
+        name = malloc(size);
         if (!name)
                 return -1;
 
         self->adjust_symbols = 0;
 
         if (strncmp(self->name, "/tmp/perf-", 10) == 0) {
-                ret = dso__load_perf_map(self, filter, v);
+                ret = dso__load_perf_map(self, map, filter);
                 self->origin = ret > 0 ? DSO__ORIG_JAVA_JIT :
                                          DSO__ORIG_NOT_FOUND;
                 return ret;
         }
 
-        self->origin = DSO__ORIG_FEDORA - 1;
+        self->origin = DSO__ORIG_BUILD_ID_CACHE;
 
+        if (self->has_build_id) {
+                build_id__sprintf(self->build_id, sizeof(self->build_id),
+                                  build_id_hex);
+                snprintf(name, size, "%s/%s/.build-id/%.2s/%s",
+                         getenv("HOME"), DEBUG_CACHE_DIR,
+                         build_id_hex, build_id_hex + 2);
+                goto open_file;
+        }
 more:
         do {
                 self->origin++;
                 switch (self->origin) {
                 case DSO__ORIG_FEDORA:
-                        snprintf(name, size, "/usr/lib/debug%s.debug", self->name);
+                        snprintf(name, size, "/usr/lib/debug%s.debug",
+                                 self->long_name);
                         break;
                 case DSO__ORIG_UBUNTU:
-                        snprintf(name, size, "/usr/lib/debug%s", self->name);
+                        snprintf(name, size, "/usr/lib/debug%s",
+                                 self->long_name);
                         break;
                 case DSO__ORIG_BUILDID:
-                        build_id = dso__read_build_id(self, v);
-                        if (build_id != NULL) {
+                        if (filename__read_build_id(self->long_name, build_id,
+                                                    sizeof(build_id))) {
+                                build_id__sprintf(build_id, sizeof(build_id),
+                                                  build_id_hex);
                                 snprintf(name, size,
                                          "/usr/lib/debug/.build-id/%.2s/%s.debug",
-                                        build_id, build_id + 2);
-                                free(build_id);
+                                        build_id_hex, build_id_hex + 2);
+                                if (self->has_build_id)
+                                        goto compare_build_id;
                                 break;
                         }
                         self->origin++;
                         /* Fall thru */
                 case DSO__ORIG_DSO:
-                        snprintf(name, size, "%s", self->name);
+                        snprintf(name, size, "%s", self->long_name);
                         break;
 
                 default:
                         goto out;
                 }
 
+                if (self->has_build_id) {
+                        if (filename__read_build_id(name, build_id,
+                                                    sizeof(build_id)) < 0)
+                                goto more;
+compare_build_id:
+                        if (!dso__build_id_equal(self, build_id))
+                                goto more;
+                }
+open_file:
                 fd = open(name, O_RDONLY);
         } while (fd < 0);
 
-        ret = dso__load_sym(self, fd, name, filter, v, NULL);
+        ret = dso__load_sym(self, map, name, fd, filter, 0);
         close(fd);
 
         /*
@@ -796,7 +1348,7 @@ more:
                 goto more;
 
         if (ret > 0) {
-                int nr_plt = dso__synthesize_plt_symbols(self, v);
+                int nr_plt = dso__synthesize_plt_symbols(self, map, filter);
                 if (nr_plt > 0)
                         ret += nr_plt;
         }
@@ -807,231 +1359,608 @@ out:
         return ret;
 }
 
-static int dso__load_module(struct dso *self, struct mod_dso *mods, const char *name,
-                             symbol_filter_t filter, int v)
+struct map *map_groups__find_by_name(struct map_groups *self,
+                                     enum map_type type, const char *name)
 {
-        struct module *mod = mod_dso__find_module(mods, name);
-        int err = 0, fd;
+        struct rb_node *nd;
 
-        if (mod == NULL || !mod->active)
-                return err;
+        for (nd = rb_first(&self->maps[type]); nd; nd = rb_next(nd)) {
+                struct map *map = rb_entry(nd, struct map, rb_node);
 
-        fd = open(mod->path, O_RDONLY);
+                if (map->dso && strcmp(map->dso->short_name, name) == 0)
+                        return map;
+        }
 
-        if (fd < 0)
-                return err;
+        return NULL;
+}
 
-        err = dso__load_sym(self, fd, name, filter, v, mod);
-        close(fd);
+static int dso__kernel_module_get_build_id(struct dso *self)
+{
+        char filename[PATH_MAX];
+        /*
+         * kernel module short names are of the form "[module]" and
+         * we need just "module" here.
+         */
+        const char *name = self->short_name + 1;
 
-        return err;
+        snprintf(filename, sizeof(filename),
+                 "/sys/module/%.*s/notes/.note.gnu.build-id",
+                 (int)strlen(name - 1), name);
+
+        if (sysfs__read_build_id(filename, self->build_id,
+                                 sizeof(self->build_id)) == 0)
+                self->has_build_id = true;
+
+        return 0;
 }
 
-int dso__load_modules(struct dso *self, symbol_filter_t filter, int v)
+static int map_groups__set_modules_path_dir(struct map_groups *self, char *dirname)
 {
-        struct mod_dso *mods = mod_dso__new_dso("modules");
-        struct module *pos;
-        struct rb_node *next;
-        int err, count = 0;
+        struct dirent *dent;
+        DIR *dir = opendir(dirname);
 
-        err = mod_dso__load_modules(mods);
+        if (!dir) {
+                pr_debug("%s: cannot open %s dir\n", __func__, dirname);
+                return -1;
+        }
 
-        if (err <= 0)
-                return err;
+        while ((dent = readdir(dir)) != NULL) {
+                char path[PATH_MAX];
+
+                if (dent->d_type == DT_DIR) {
+                        if (!strcmp(dent->d_name, ".") ||
+                            !strcmp(dent->d_name, ".."))
+                                continue;
+
+                        snprintf(path, sizeof(path), "%s/%s",
+                                 dirname, dent->d_name);
+                        if (map_groups__set_modules_path_dir(self, path) < 0)
+                                goto failure;
+                } else {
+                        char *dot = strrchr(dent->d_name, '.'),
+                             dso_name[PATH_MAX];
+                        struct map *map;
+                        char *long_name;
+
+                        if (dot == NULL || strcmp(dot, ".ko"))
+                                continue;
+                        snprintf(dso_name, sizeof(dso_name), "[%.*s]",
+                                 (int)(dot - dent->d_name), dent->d_name);
+
+                        strxfrchar(dso_name, '-', '_');
+                        map = map_groups__find_by_name(self, MAP__FUNCTION, dso_name);
+                        if (map == NULL)
+                                continue;
+
+                        snprintf(path, sizeof(path), "%s/%s",
+                                 dirname, dent->d_name);
+
+                        long_name = strdup(path);
+                        if (long_name == NULL)
+                                goto failure;
+                        dso__set_long_name(map->dso, long_name);
+                        dso__kernel_module_get_build_id(map->dso);
+                }
+        }
 
-        /*
-         * Iterate over modules, and load active symbols.
-         */
-        next = rb_first(&mods->mods);
-        while (next) {
-                pos = rb_entry(next, struct module, rb_node);
-                err = dso__load_module(self, mods, pos->name, filter, v);
+        return 0;
+failure:
+        closedir(dir);
+        return -1;
+}
 
-                if (err < 0)
-                        break;
+static int map_groups__set_modules_path(struct map_groups *self)
+{
+        struct utsname uts;
+        char modules_path[PATH_MAX];
 
-                next = rb_next(&pos->rb_node);
-                count += err;
-        }
+        if (uname(&uts) < 0)
+                return -1;
+
+        snprintf(modules_path, sizeof(modules_path), "/lib/modules/%s/kernel",
+                 uts.release);
+
+        return map_groups__set_modules_path_dir(self, modules_path);
+}
 
-        if (err < 0) {
-                mod_dso__delete_modules(mods);
-                mod_dso__delete_self(mods);
-                return err;
+/*
+ * Constructor variant for modules (where we know from /proc/modules where
+ * they are loaded) and for vmlinux, where only after we load all the
+ * symbols we'll know where it starts and ends.
+ */
+static struct map *map__new2(u64 start, struct dso *dso, enum map_type type)
+{
+        struct map *self = zalloc(sizeof(*self) +
+                                  (dso->kernel ? sizeof(struct kmap) : 0));
+        if (self != NULL) {
+                /*
+                 * ->end will be filled after we load all the symbols
+                 */
+                map__init(self, type, start, 0, 0, dso);
         }
 
-        return count;
+        return self;
 }
 
-static inline void dso__fill_symbol_holes(struct dso *self)
+struct map *map_groups__new_module(struct map_groups *self, u64 start,
+                                   const char *filename)
 {
-        struct symbol *prev = NULL;
-        struct rb_node *nd;
+        struct map *map;
+        struct dso *dso = __dsos__findnew(&dsos__kernel, filename);
 
-        for (nd = rb_last(&self->syms); nd; nd = rb_prev(nd)) {
-                struct symbol *pos = rb_entry(nd, struct symbol, rb_node);
+        if (dso == NULL)
+                return NULL;
 
-                if (prev) {
-                        u64 hole = 0;
-                        int alias = pos->start == prev->start;
+        map = map__new2(start, dso, MAP__FUNCTION);
+        if (map == NULL)
+                return NULL;
 
-                        if (!alias)
-                                hole = prev->start - pos->end - 1;
+        dso->origin = DSO__ORIG_KMODULE;
+        map_groups__insert(self, map);
+        return map;
+}
 
-                        if (hole || alias) {
-                                if (alias)
-                                        pos->end = prev->end;
-                                else if (hole)
-                                        pos->end = prev->start - 1;
-                        }
-                }
-                prev = pos;
+static int map_groups__create_modules(struct map_groups *self)
+{
+        char *line = NULL;
+        size_t n;
+        FILE *file = fopen("/proc/modules", "r");
+        struct map *map;
+
+        if (file == NULL)
+                return -1;
+
+        while (!feof(file)) {
+                char name[PATH_MAX];
+                u64 start;
+                char *sep;
+                int line_len;
+
+                line_len = getline(&line, &n, file);
+                if (line_len < 0)
+                        break;
+
+                if (!line)
+                        goto out_failure;
+
+                line[--line_len] = '\0'; /* \n */
+
+                sep = strrchr(line, 'x');
+                if (sep == NULL)
+                        continue;
+
+                hex2u64(sep + 1, &start);
+
+                sep = strchr(line, ' ');
+                if (sep == NULL)
+                        continue;
+
+                *sep = '\0';
+
+                snprintf(name, sizeof(name), "[%s]", line);
+                map = map_groups__new_module(self, start, name);
+                if (map == NULL)
+                        goto out_delete_line;
+                dso__kernel_module_get_build_id(map->dso);
         }
+
+        free(line);
+        fclose(file);
+
+        return map_groups__set_modules_path(self);
+
+out_delete_line:
+        free(line);
+out_failure:
+        return -1;
 }
 
-static int dso__load_vmlinux(struct dso *self, const char *vmlinux,
-                             symbol_filter_t filter, int v)
+static int dso__load_vmlinux(struct dso *self, struct map *map,
+                             const char *vmlinux, symbol_filter_t filter)
 {
-        int err, fd = open(vmlinux, O_RDONLY);
+        int err = -1, fd;
+
+        if (self->has_build_id) {
+                u8 build_id[BUILD_ID_SIZE];
+
+                if (filename__read_build_id(vmlinux, build_id,
+                                            sizeof(build_id)) < 0) {
+                        pr_debug("No build_id in %s, ignoring it\n", vmlinux);
+                        return -1;
+                }
+                if (!dso__build_id_equal(self, build_id)) {
+                        char expected_build_id[BUILD_ID_SIZE * 2 + 1],
+                             vmlinux_build_id[BUILD_ID_SIZE * 2 + 1];
+
+                        build_id__sprintf(self->build_id,
+                                          sizeof(self->build_id),
+                                          expected_build_id);
+                        build_id__sprintf(build_id, sizeof(build_id),
+                                          vmlinux_build_id);
+                        pr_debug("build_id in %s is %s while expected is %s, "
+                                 "ignoring it\n", vmlinux, vmlinux_build_id,
+                                 expected_build_id);
+                        return -1;
+                }
+        }
 
+        fd = open(vmlinux, O_RDONLY);
         if (fd < 0)
                 return -1;
 
-        err = dso__load_sym(self, fd, vmlinux, filter, v, NULL);
+        dso__set_loaded(self, map->type);
+        err = dso__load_sym(self, map, vmlinux, fd, filter, 0);
+        close(fd);
 
         if (err > 0)
-                dso__fill_symbol_holes(self);
+                pr_debug("Using %s for symbols\n", vmlinux);
 
-        close(fd);
+        return err;
+}
+
+int dso__load_vmlinux_path(struct dso *self, struct map *map,
+                           symbol_filter_t filter)
+{
+        int i, err = 0;
+
+        pr_debug("Looking at the vmlinux_path (%d entries long)\n",
+                 vmlinux_path__nr_entries);
+
+        for (i = 0; i < vmlinux_path__nr_entries; ++i) {
+                err = dso__load_vmlinux(self, map, vmlinux_path[i], filter);
+                if (err > 0) {
+                        dso__set_long_name(self, strdup(vmlinux_path[i]));
+                        break;
+                }
+        }
 
         return err;
 }
 
-int dso__load_kernel(struct dso *self, const char *vmlinux,
-                     symbol_filter_t filter, int v, int use_modules)
+static int dso__load_kernel_sym(struct dso *self, struct map *map,
+                                symbol_filter_t filter)
 {
-        int err = -1;
+        int err;
+        const char *kallsyms_filename = NULL;
+        char *kallsyms_allocated_filename = NULL;
+        /*
+         * Step 1: if the user specified a vmlinux filename, use it and only
+         * it, reporting errors to the user if it cannot be used.
+         *
+         * For instance, try to analyse an ARM perf.data file _without_ a
+         * build-id, or if the user specifies the wrong path to the right
+         * vmlinux file, obviously we can't fallback to another vmlinux (a
+         * x86_86 one, on the machine where analysis is being performed, say),
+         * or worse, /proc/kallsyms.
+         *
+         * If the specified file _has_ a build-id and there is a build-id
+         * section in the perf.data file, we will still do the expected
+         * validation in dso__load_vmlinux and will bail out if they don't
+         * match.
+         */
+        if (symbol_conf.vmlinux_name != NULL) {
+                err = dso__load_vmlinux(self, map,
+                                        symbol_conf.vmlinux_name, filter);
+                goto out_try_fixup;
+        }
 
-        if (vmlinux) {
-                err = dso__load_vmlinux(self, vmlinux, filter, v);
-                if (err > 0 && use_modules) {
-                        int syms = dso__load_modules(self, filter, v);
+        if (vmlinux_path != NULL) {
+                err = dso__load_vmlinux_path(self, map, filter);
+                if (err > 0)
+                        goto out_fixup;
+        }
 
-                        if (syms < 0) {
-                                fprintf(stderr, "dso__load_modules failed!\n");
-                                return syms;
+        /*
+         * Say the kernel DSO was created when processing the build-id header table,
+         * we have a build-id, so check if it is the same as the running kernel,
+         * using it if it is.
+         */
+        if (self->has_build_id) {
+                u8 kallsyms_build_id[BUILD_ID_SIZE];
+                char sbuild_id[BUILD_ID_SIZE * 2 + 1];
+
+                if (sysfs__read_build_id("/sys/kernel/notes", kallsyms_build_id,
+                                         sizeof(kallsyms_build_id)) == 0) {
+                        if (dso__build_id_equal(self, kallsyms_build_id)) {
+                                kallsyms_filename = "/proc/kallsyms";
+                                goto do_kallsyms;
                         }
-                        err += syms;
                 }
-        }
+                /*
+                 * Now look if we have it on the build-id cache in
+                 * $HOME/.debug/[kernel.kallsyms].
+                 */
+                build_id__sprintf(self->build_id, sizeof(self->build_id),
+                                  sbuild_id);
+
+                if (asprintf(&kallsyms_allocated_filename,
+                             "%s/.debug/[kernel.kallsyms]/%s",
+                             getenv("HOME"), sbuild_id) == -1) {
+                        pr_err("Not enough memory for kallsyms file lookup\n");
+                        return -1;
+                }
 
-        if (err <= 0)
-                err = dso__load_kallsyms(self, filter, v);
+                kallsyms_filename = kallsyms_allocated_filename;
 
+                if (access(kallsyms_filename, F_OK)) {
+                        pr_err("No kallsyms or vmlinux with build-id %s "
+                               "was found\n", sbuild_id);
+                        free(kallsyms_allocated_filename);
+                        return -1;
+                }
+        } else {
+                /*
+                 * Last resort, if we don't have a build-id and couldn't find
+                 * any vmlinux file, try the running kernel kallsyms table.
+                 */
+                kallsyms_filename = "/proc/kallsyms";
+        }
+
+do_kallsyms:
+        err = dso__load_kallsyms(self, kallsyms_filename, map, filter);
         if (err > 0)
-                self->origin = DSO__ORIG_KERNEL;
+                pr_debug("Using %s for symbols\n", kallsyms_filename);
+        free(kallsyms_allocated_filename);
+
+out_try_fixup:
+        if (err > 0) {
+out_fixup:
+                if (kallsyms_filename != NULL)
+                        dso__set_long_name(self, strdup("[kernel.kallsyms]"));
+                map__fixup_start(map);
+                map__fixup_end(map);
+        }
 
         return err;
 }
 
-LIST_HEAD(dsos);
-struct dso      *kernel_dso;
-struct dso      *vdso;
-struct dso      *hypervisor_dso;
-
-const char      *vmlinux_name = "vmlinux";
-int             modules;
+LIST_HEAD(dsos__user);
+LIST_HEAD(dsos__kernel);
 
-static void dsos__add(struct dso *dso)
+static void dsos__add(struct list_head *head, struct dso *dso)
 {
-        list_add_tail(&dso->node, &dsos);
+        list_add_tail(&dso->node, head);
 }
 
-static struct dso *dsos__find(const char *name)
+static struct dso *dsos__find(struct list_head *head, const char *name)
 {
         struct dso *pos;
 
-        list_for_each_entry(pos, &dsos, node)
-                if (strcmp(pos->name, name) == 0)
+        list_for_each_entry(pos, head, node)
+                if (strcmp(pos->long_name, name) == 0)
                         return pos;
         return NULL;
 }
 
-struct dso *dsos__findnew(const char *name)
+struct dso *__dsos__findnew(struct list_head *head, const char *name)
 {
-        struct dso *dso = dsos__find(name);
-        int nr;
-
-        if (dso)
-                return dso;
-
-        dso = dso__new(name, 0);
-        if (!dso)
-                goto out_delete_dso;
+        struct dso *dso = dsos__find(head, name);
 
-        nr = dso__load(dso, NULL, verbose);
-        if (nr < 0) {
-                eprintf("Failed to open: %s\n", name);
-                goto out_delete_dso;
+        if (!dso) {
+                dso = dso__new(name);
+                if (dso != NULL) {
+                        dsos__add(head, dso);
+                        dso__set_basename(dso);
+                }
         }
-        if (!nr)
-                eprintf("No symbols found in: %s, maybe install a debug package?\n", name);
-
-        dsos__add(dso);
 
         return dso;
+}
 
-out_delete_dso:
-        dso__delete(dso);
-        return NULL;
+static void __dsos__fprintf(struct list_head *head, FILE *fp)
+{
+        struct dso *pos;
+
+        list_for_each_entry(pos, head, node) {
+                int i;
+                for (i = 0; i < MAP__NR_TYPES; ++i)
+                        dso__fprintf(pos, i, fp);
+        }
 }
 
 void dsos__fprintf(FILE *fp)
 {
+        __dsos__fprintf(&dsos__kernel, fp);
+        __dsos__fprintf(&dsos__user, fp);
+}
+
+static size_t __dsos__fprintf_buildid(struct list_head *head, FILE *fp,
+                                      bool with_hits)
+{
         struct dso *pos;
+        size_t ret = 0;
 
-        list_for_each_entry(pos, &dsos, node)
-                dso__fprintf(pos, fp);
+        list_for_each_entry(pos, head, node) {
+                if (with_hits && !pos->hit)
+                        continue;
+                ret += dso__fprintf_buildid(pos, fp);
+                ret += fprintf(fp, " %s\n", pos->long_name);
+        }
+        return ret;
 }
 
-static struct symbol *vdso__find_symbol(struct dso *dso, u64 ip)
+size_t dsos__fprintf_buildid(FILE *fp, bool with_hits)
 {
-        return dso__find_symbol(dso, ip);
+        return (__dsos__fprintf_buildid(&dsos__kernel, fp, with_hits) +
+                __dsos__fprintf_buildid(&dsos__user, fp, with_hits));
 }
 
-int load_kernel(void)
+struct dso *dso__new_kernel(const char *name)
 {
-        int err;
+        struct dso *self = dso__new(name ?: "[kernel.kallsyms]");
 
-        kernel_dso = dso__new("[kernel]", 0);
-        if (!kernel_dso)
-                return -1;
+        if (self != NULL) {
+                dso__set_short_name(self, "[kernel]");
+                self->kernel     = 1;
+        }
 
-        err = dso__load_kernel(kernel_dso, vmlinux_name, NULL, verbose, modules);
-        if (err <= 0) {
-                dso__delete(kernel_dso);
-                kernel_dso = NULL;
-        } else
-                dsos__add(kernel_dso);
+        return self;
+}
 
-        vdso = dso__new("[vdso]", 0);
-        if (!vdso)
-                return -1;
+void dso__read_running_kernel_build_id(struct dso *self)
+{
+        if (sysfs__read_build_id("/sys/kernel/notes", self->build_id,
+                                 sizeof(self->build_id)) == 0)
+                self->has_build_id = true;
+}
+
+static struct dso *dsos__create_kernel(const char *vmlinux)
+{
+        struct dso *kernel = dso__new_kernel(vmlinux);
+
+        if (kernel != NULL) {
+                dso__read_running_kernel_build_id(kernel);
+                dsos__add(&dsos__kernel, kernel);
+        }
+
+        return kernel;
+}
+
+int __map_groups__create_kernel_maps(struct map_groups *self,
+                                     struct map *vmlinux_maps[MAP__NR_TYPES],
+                                     struct dso *kernel)
+{
+        enum map_type type;
+
+        for (type = 0; type < MAP__NR_TYPES; ++type) {
+                struct kmap *kmap;
+
+                vmlinux_maps[type] = map__new2(0, kernel, type);
+                if (vmlinux_maps[type] == NULL)
+                        return -1;
+
+                vmlinux_maps[type]->map_ip =
+                        vmlinux_maps[type]->unmap_ip = identity__map_ip;
+
+                kmap = map__kmap(vmlinux_maps[type]);
+                kmap->kmaps = self;
+                map_groups__insert(self, vmlinux_maps[type]);
+        }
+
+        return 0;
+}
+
+static void vmlinux_path__exit(void)
+{
+        while (--vmlinux_path__nr_entries >= 0) {
+                free(vmlinux_path[vmlinux_path__nr_entries]);
+                vmlinux_path[vmlinux_path__nr_entries] = NULL;
+        }
 
-        vdso->find_symbol = vdso__find_symbol;
+        free(vmlinux_path);
+        vmlinux_path = NULL;
+}
 
-        dsos__add(vdso);
+static int vmlinux_path__init(void)
+{
+        struct utsname uts;
+        char bf[PATH_MAX];
 
-        hypervisor_dso = dso__new("[hypervisor]", 0);
-        if (!hypervisor_dso)
+        if (uname(&uts) < 0)
                 return -1;
-        dsos__add(hypervisor_dso);
 
-        return err;
+        vmlinux_path = malloc(sizeof(char *) * 5);
+        if (vmlinux_path == NULL)
+                return -1;
+
+        vmlinux_path[vmlinux_path__nr_entries] = strdup("vmlinux");
+        if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
+                goto out_fail;
+        ++vmlinux_path__nr_entries;
+        vmlinux_path[vmlinux_path__nr_entries] = strdup("/boot/vmlinux");
+        if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
+                goto out_fail;
+        ++vmlinux_path__nr_entries;
+        snprintf(bf, sizeof(bf), "/boot/vmlinux-%s", uts.release);
+        vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
+        if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
+                goto out_fail;
+        ++vmlinux_path__nr_entries;
+        snprintf(bf, sizeof(bf), "/lib/modules/%s/build/vmlinux", uts.release);
+        vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
+        if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
+                goto out_fail;
+        ++vmlinux_path__nr_entries;
+        snprintf(bf, sizeof(bf), "/usr/lib/debug/lib/modules/%s/vmlinux",
+                 uts.release);
+        vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
+        if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
+                goto out_fail;
+        ++vmlinux_path__nr_entries;
+
+        return 0;
+
+out_fail:
+        vmlinux_path__exit();
+        return -1;
 }
 
+static int setup_list(struct strlist **list, const char *list_str,
+                      const char *list_name)
+{
+        if (list_str == NULL)
+                return 0;
+
+        *list = strlist__new(true, list_str);
+        if (!*list) {
+                pr_err("problems parsing %s list\n", list_name);
+                return -1;
+        }
+        return 0;
+}
 
-void symbol__init(void)
+int symbol__init(void)
 {
         elf_version(EV_CURRENT);
+        if (symbol_conf.sort_by_name)
+                symbol_conf.priv_size += (sizeof(struct symbol_name_rb_node) -
+                                          sizeof(struct symbol));
+
+        if (symbol_conf.try_vmlinux_path && vmlinux_path__init() < 0)
+                return -1;
+
+        if (symbol_conf.field_sep && *symbol_conf.field_sep == '.') {
+                pr_err("'.' is the only non valid --field-separator argument\n");
+                return -1;
+        }
+
+        if (setup_list(&symbol_conf.dso_list,
+                       symbol_conf.dso_list_str, "dso") < 0)
+                return -1;
+
+        if (setup_list(&symbol_conf.comm_list,
+                       symbol_conf.comm_list_str, "comm") < 0)
+                goto out_free_dso_list;
+
+        if (setup_list(&symbol_conf.sym_list,
+                       symbol_conf.sym_list_str, "symbol") < 0)
+                goto out_free_comm_list;
+
+        return 0;
+
+out_free_dso_list:
+        strlist__delete(symbol_conf.dso_list);
+out_free_comm_list:
+        strlist__delete(symbol_conf.comm_list);
+        return -1;
+}
+
+int map_groups__create_kernel_maps(struct map_groups *self,
+                                   struct map *vmlinux_maps[MAP__NR_TYPES])
+{
+        struct dso *kernel = dsos__create_kernel(symbol_conf.vmlinux_name);
+
+        if (kernel == NULL)
+                return -1;
+
+        if (__map_groups__create_kernel_maps(self, vmlinux_maps, kernel) < 0)
+                return -1;
+
+        if (symbol_conf.use_modules && map_groups__create_modules(self) < 0)
+                pr_debug("Problems creating module maps, continuing anyway...\n");
+        /*
+         * Now that we have all the maps created, just set the ->end of them:
+         */
+        map_groups__fixup_end(self);
+        return 0;
 }