6 files changed, 165 insertions, 9 deletions

diff --git a/tools/perf/Makefile b/tools/perf/Makefile
index fafea0b6f323..7c846424aebf 100644
--- a/tools/perf/Makefile
+++ b/tools/perf/Makefile
@@ -425,6 +425,7 @@ LIB_OBJS += util/svghelper.o
 LIB_OBJS += util/sort.o
 LIB_OBJS += util/hist.o
 LIB_OBJS += util/probe-event.o
+LIB_OBJS += util/util.o
 
 BUILTIN_OBJS += builtin-annotate.o
 
diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index 8a0bca55106f..df237c3a041b 100644
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -169,20 +169,23 @@ static int do_write(int fd, const void *buf, size_t size)
         return 0;
 }
 
+#define dsos__for_each_with_build_id(pos, head) \
+        list_for_each_entry(pos, head, node)    \
+                if (!pos->has_build_id)         \
+                        continue;               \
+                else
+
 static int __dsos__write_buildid_table(struct list_head *head, int fd)
 {
 #define NAME_ALIGN      64
         struct dso *pos;
         static const char zero_buf[NAME_ALIGN];
 
-        list_for_each_entry(pos, head, node) {
+        dsos__for_each_with_build_id(pos, head) {
                 int err;
                 struct build_id_event b;
-                size_t len;
+                size_t len = pos->long_name_len + 1;
 
-                if (!pos->has_build_id)
-                        continue;
-                len = pos->long_name_len + 1;
                 len = ALIGN(len, NAME_ALIGN);
                 memset(&b, 0, sizeof(b));
                 memcpy(&b.build_id, pos->build_id, sizeof(pos->build_id));
@@ -209,6 +212,74 @@ static int dsos__write_buildid_table(int fd)
         return err;
 }
 
+static int dso__cache_build_id(struct dso *self, const char *debugdir)
+{
+        const size_t size = PATH_MAX;
+        char *filename = malloc(size),
+             *linkname = malloc(size), *targetname, *sbuild_id;
+        int len, err = -1;
+
+        if (filename == NULL || linkname == NULL)
+                goto out_free;
+
+        len = snprintf(filename, size, "%s%s", debugdir, self->long_name);
+        if (mkdir_p(filename, 0755))
+                goto out_free;
+
+        len += snprintf(filename + len, sizeof(filename) - len, "/");
+        sbuild_id = filename + len;
+        build_id__sprintf(self->build_id, sizeof(self->build_id), sbuild_id);
+
+        if (access(filename, F_OK) && link(self->long_name, filename) &&
+            copyfile(self->long_name, filename))
+                goto out_free;
+
+        len = snprintf(linkname, size, "%s/.build-id/%.2s",
+                       debugdir, sbuild_id);
+
+        if (access(linkname, X_OK) && mkdir_p(linkname, 0755))
+                goto out_free;
+
+        snprintf(linkname + len, size - len, "/%s", sbuild_id + 2);
+        targetname = filename + strlen(debugdir) - 5;
+        memcpy(targetname, "../..", 5);
+
+        if (symlink(targetname, linkname) == 0)
+                err = 0;
+out_free:
+        free(filename);
+        free(linkname);
+        return err;
+}
+
+static int __dsos__cache_build_ids(struct list_head *head, const char *debugdir)
+{
+        struct dso *pos;
+        int err = 0;
+
+        dsos__for_each_with_build_id(pos, head)
+                if (dso__cache_build_id(pos, debugdir))
+                        err = -1;
+
+        return err;
+}
+
+static int dsos__cache_build_ids(void)
+{
+        int err_kernel, err_user;
+        char debugdir[PATH_MAX];
+
+        snprintf(debugdir, sizeof(debugdir), "%s/%s", getenv("HOME"),
+                 DEBUG_CACHE_DIR);
+
+        if (mkdir(debugdir, 0755) != 0 && errno != EEXIST)
+                return -1;
+
+        err_kernel = __dsos__cache_build_ids(&dsos__kernel, debugdir);
+        err_user   = __dsos__cache_build_ids(&dsos__user, debugdir);
+        return err_kernel || err_user ? -1 : 0;
+}
+
 static int perf_header__adds_write(struct perf_header *self, int fd)
 {
         int nr_sections;
@@ -258,6 +329,7 @@ static int perf_header__adds_write(struct perf_header *self, int fd)
                         goto out_free;
                 }
                 buildid_sec->size = lseek(fd, 0, SEEK_CUR) - buildid_sec->offset;
+                dsos__cache_build_ids();
         }
 
         lseek(fd, sec_start, SEEK_SET);
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index ab92763edb03..79ca6a099f96 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -22,6 +22,7 @@
 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,
@@ -1191,6 +1192,7 @@ 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',
@@ -1209,6 +1211,7 @@ int dso__load(struct dso *self, struct map *map, struct perf_session *session,
         int size = PATH_MAX;
         char *name;
         u8 build_id[BUILD_ID_SIZE];
+        char build_id_hex[BUILD_ID_SIZE * 2 + 1];
         int ret = -1;
         int fd;
 
@@ -1230,8 +1233,16 @@ int dso__load(struct dso *self, struct map *map, struct perf_session *session,
                 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++;
@@ -1247,8 +1258,6 @@ more:
                 case DSO__ORIG_BUILDID:
                         if (filename__read_build_id(self->long_name, build_id,
                                                     sizeof(build_id))) {
-                                char build_id_hex[BUILD_ID_SIZE * 2 + 1];
-
                                 build_id__sprintf(build_id, sizeof(build_id),
                                                   build_id_hex);
                                 snprintf(name, size,
@@ -1276,7 +1285,7 @@ compare_build_id:
                         if (!dso__build_id_equal(self, build_id))
                                 goto more;
                 }
-
+open_file:
                 fd = open(name, O_RDONLY);
         } while (fd < 0);
 
diff --git a/tools/perf/util/symbol.h b/tools/perf/util/symbol.h
index 9eabd60f819d..f27e158943e9 100644
--- a/tools/perf/util/symbol.h
+++ b/tools/perf/util/symbol.h
@@ -8,6 +8,8 @@
 #include <linux/rbtree.h>
 #include "event.h"
 
+#define DEBUG_CACHE_DIR ".debug"
+
 #ifdef HAVE_CPLUS_DEMANGLE
 extern char *cplus_demangle(const char *, int);
 
diff --git a/tools/perf/util/util.c b/tools/perf/util/util.c
new file mode 100644
index 000000000000..f3c0798a5e78
--- /dev/null
+++ b/tools/perf/util/util.c
@@ -0,0 +1,69 @@
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <fcntl.h>
+#include <string.h>
+#include <unistd.h>
+#include "util.h"
+
+int mkdir_p(char *path, mode_t mode)
+{
+        struct stat st;
+        int err;
+        char *d = path;
+
+        if (*d != '/')
+                return -1;
+
+        if (stat(path, &st) == 0)
+                return 0;
+
+        while (*++d == '/');
+
+        while ((d = strchr(d, '/'))) {
+                *d = '\0';
+                err = stat(path, &st) && mkdir(path, mode);
+                *d++ = '/';
+                if (err)
+                        return -1;
+                while (*d == '/')
+                        ++d;
+        }
+        return (stat(path, &st) && mkdir(path, mode)) ? -1 : 0;
+}
+
+int copyfile(const char *from, const char *to)
+{
+        int fromfd, tofd;
+        struct stat st;
+        void *addr;
+        int err = -1;
+
+        if (stat(from, &st))
+                goto out;
+
+        fromfd = open(from, O_RDONLY);
+        if (fromfd < 0)
+                goto out;
+
+        tofd = creat(to, 0755);
+        if (tofd < 0)
+                goto out_close_from;
+
+        addr = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fromfd, 0);
+        if (addr == MAP_FAILED)
+                goto out_close_to;
+
+        if (write(tofd, addr, st.st_size) == st.st_size)
+                err = 0;
+
+        munmap(addr, st.st_size);
+out_close_to:
+        close(tofd);
+        if (err)
+                unlink(to);
+out_close_from:
+        close(fromfd);
+out:
+        return err;
+}
diff --git a/tools/perf/util/util.h b/tools/perf/util/util.h
index c673d8825883..0f5b2a6f1080 100644
--- a/tools/perf/util/util.h
+++ b/tools/perf/util/util.h
@@ -403,4 +403,7 @@ void git_qsort(void *base, size_t nmemb, size_t size,
 #endif
 #endif
 
+int mkdir_p(char *path, mode_t mode);
+int copyfile(const char *from, const char *to);
+
 #endif