perf: Fix performance issue with perf report
[safe/jmp/linux-2.6] / tools / perf / util / header.c
index 726a0eb..8847bec 100644 (file)
@@ -1,15 +1,19 @@
+#define _FILE_OFFSET_BITS 64
+
 #include <sys/types.h>
+#include <byteswap.h>
 #include <unistd.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <linux/list.h>
+#include <linux/kernel.h>
 
 #include "util.h"
 #include "header.h"
 #include "../perf.h"
 #include "trace-event.h"
+#include "session.h"
 #include "symbol.h"
-#include "data_map.h"
 #include "debug.h"
 
 /*
@@ -58,36 +62,28 @@ int perf_header_attr__add_id(struct perf_header_attr *self, u64 id)
        return 0;
 }
 
-/*
- * Create new perf.data header:
- */
-struct perf_header *perf_header__new(void)
+int perf_header__init(struct perf_header *self)
 {
-       struct perf_header *self = calloc(sizeof(*self), 1);
-
-       if (self != NULL) {
-               self->size = 1;
-               self->attr = malloc(sizeof(void *));
-
-               if (self->attr == NULL) {
-                       free(self);
-                       self = NULL;
-               }
-       }
+       self->size = 1;
+       self->attr = malloc(sizeof(void *));
+       return self->attr == NULL ? -ENOMEM : 0;
+}
 
-       return self;
+void perf_header__exit(struct perf_header *self)
+{
+       int i;
+       for (i = 0; i < self->attrs; ++i)
+                perf_header_attr__delete(self->attr[i]);
+       free(self->attr);
 }
 
 int perf_header__add_attr(struct perf_header *self,
                          struct perf_header_attr *attr)
 {
-       int pos = self->attrs;
-
        if (self->frozen)
                return -1;
 
-       self->attrs++;
-       if (self->attrs > self->size) {
+       if (self->attrs == self->size) {
                int nsize = self->size * 2;
                struct perf_header_attr **nattr;
 
@@ -98,38 +94,36 @@ int perf_header__add_attr(struct perf_header *self,
                self->size = nsize;
                self->attr = nattr;
        }
-       self->attr[pos] = attr;
+
+       self->attr[self->attrs++] = attr;
        return 0;
 }
 
-#define MAX_EVENT_NAME 64
-
-struct perf_trace_event_type {
-       u64     event_id;
-       char    name[MAX_EVENT_NAME];
-};
-
 static int event_count;
 static struct perf_trace_event_type *events;
 
-void perf_header__push_event(u64 id, const char *name)
+int perf_header__push_event(u64 id, const char *name)
 {
        if (strlen(name) > MAX_EVENT_NAME)
                pr_warning("Event %s will be truncated\n", name);
 
        if (!events) {
                events = malloc(sizeof(struct perf_trace_event_type));
-               if (!events)
-                       die("nomem");
+               if (events == NULL)
+                       return -ENOMEM;
        } else {
-               events = realloc(events, (event_count + 1) * sizeof(struct perf_trace_event_type));
-               if (!events)
-                       die("nomem");
+               struct perf_trace_event_type *nevents;
+
+               nevents = realloc(events, (event_count + 1) * sizeof(*events));
+               if (nevents == NULL)
+                       return -ENOMEM;
+               events = nevents;
        }
        memset(&events[event_count], 0, sizeof(struct perf_trace_event_type));
        events[event_count].event_id = id;
        strncpy(events[event_count].name, name, MAX_EVENT_NAME - 1);
        event_count++;
+       return 0;
 }
 
 char *perf_header__find_event(u64 id)
@@ -161,53 +155,270 @@ bool perf_header__has_feat(const struct perf_header *self, int feat)
        return test_bit(feat, self->adds_features);
 }
 
-static void do_write(int fd, void *buf, size_t size)
+static int do_write(int fd, const void *buf, size_t size)
 {
        while (size) {
                int ret = write(fd, buf, size);
 
                if (ret < 0)
-                       die("failed to write");
+                       return -errno;
 
                size -= ret;
                buf += ret;
        }
+
+       return 0;
+}
+
+#define NAME_ALIGN 64
+
+static int write_padded(int fd, const void *bf, size_t count,
+                       size_t count_aligned)
+{
+       static const char zero_buf[NAME_ALIGN];
+       int err = do_write(fd, bf, count);
+
+       if (!err)
+               err = do_write(fd, zero_buf, count_aligned - count);
+
+       return err;
+}
+
+#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, pid_t pid,
+                               u16 misc, int fd)
+{
+       struct dso *pos;
+
+       dsos__for_each_with_build_id(pos, head) {
+               int err;
+               struct build_id_event b;
+               size_t len;
+
+               if (!pos->hit)
+                       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));
+               b.pid = pid;
+               b.header.misc = misc;
+               b.header.size = sizeof(b) + len;
+               err = do_write(fd, &b, sizeof(b));
+               if (err < 0)
+                       return err;
+               err = write_padded(fd, pos->long_name,
+                                  pos->long_name_len + 1, len);
+               if (err < 0)
+                       return err;
+       }
+
+       return 0;
 }
 
-static void write_buildid_table(int fd, struct list_head *id_head)
+static int dsos__write_buildid_table(struct perf_header *header, int fd)
 {
-       struct build_id_list *iter, *next;
+       struct perf_session *session = container_of(header,
+                       struct perf_session, header);
+       struct rb_node *nd;
+       int err = 0;
+       u16 kmisc, umisc;
+
+       for (nd = rb_first(&session->machines); nd; nd = rb_next(nd)) {
+               struct machine *pos = rb_entry(nd, struct machine, rb_node);
+               if (machine__is_host(pos)) {
+                       kmisc = PERF_RECORD_MISC_KERNEL;
+                       umisc = PERF_RECORD_MISC_USER;
+               } else {
+                       kmisc = PERF_RECORD_MISC_GUEST_KERNEL;
+                       umisc = PERF_RECORD_MISC_GUEST_USER;
+               }
 
-       list_for_each_entry_safe(iter, next, id_head, list) {
-               struct build_id_event *b = &iter->event;
+               err = __dsos__write_buildid_table(&pos->kernel_dsos, pos->pid,
+                                                 kmisc, fd);
+               if (err == 0)
+                       err = __dsos__write_buildid_table(&pos->user_dsos,
+                                                         pos->pid, umisc, fd);
+               if (err)
+                       break;
+       }
+       return err;
+}
 
-               do_write(fd, b, sizeof(*b));
-               do_write(fd, (void *)iter->dso_name, iter->len);
-               list_del(&iter->list);
-               free(iter);
+int build_id_cache__add_s(const char *sbuild_id, const char *debugdir,
+                         const char *name, bool is_kallsyms)
+{
+       const size_t size = PATH_MAX;
+       char *filename = malloc(size),
+            *linkname = malloc(size), *targetname;
+       int len, err = -1;
+
+       if (filename == NULL || linkname == NULL)
+               goto out_free;
+
+       len = snprintf(filename, size, "%s%s%s",
+                      debugdir, is_kallsyms ? "/" : "", name);
+       if (mkdir_p(filename, 0755))
+               goto out_free;
+
+       snprintf(filename + len, sizeof(filename) - len, "/%s", sbuild_id);
+
+       if (access(filename, F_OK)) {
+               if (is_kallsyms) {
+                        if (copyfile("/proc/kallsyms", filename))
+                               goto out_free;
+               } else if (link(name, filename) && copyfile(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 build_id_cache__add_b(const u8 *build_id, size_t build_id_size,
+                                const char *name, const char *debugdir,
+                                bool is_kallsyms)
+{
+       char sbuild_id[BUILD_ID_SIZE * 2 + 1];
+
+       build_id__sprintf(build_id, build_id_size, sbuild_id);
+
+       return build_id_cache__add_s(sbuild_id, debugdir, name, is_kallsyms);
+}
+
+int build_id_cache__remove_s(const char *sbuild_id, const char *debugdir)
+{
+       const size_t size = PATH_MAX;
+       char *filename = malloc(size),
+            *linkname = malloc(size);
+       int err = -1;
+
+       if (filename == NULL || linkname == NULL)
+               goto out_free;
+
+       snprintf(linkname, size, "%s/.build-id/%.2s/%s",
+                debugdir, sbuild_id, sbuild_id + 2);
+
+       if (access(linkname, F_OK))
+               goto out_free;
+
+       if (readlink(linkname, filename, size) < 0)
+               goto out_free;
+
+       if (unlink(linkname))
+               goto out_free;
+
+       /*
+        * Since the link is relative, we must make it absolute:
+        */
+       snprintf(linkname, size, "%s/.build-id/%.2s/%s",
+                debugdir, sbuild_id, filename);
+
+       if (unlink(linkname))
+               goto out_free;
+
+       err = 0;
+out_free:
+       free(filename);
+       free(linkname);
+       return err;
+}
+
+static int dso__cache_build_id(struct dso *self, const char *debugdir)
+{
+       bool is_kallsyms = self->kernel && self->long_name[0] != '/';
+
+       return build_id_cache__add_b(self->build_id, sizeof(self->build_id),
+                                    self->long_name, debugdir, is_kallsyms);
 }
 
-static void
-perf_header__adds_write(struct perf_header *self, int fd)
+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(struct perf_header *self)
+{
+       struct perf_session *session = container_of(self,
+                       struct perf_session, header);
+       struct rb_node *nd;
+       int ret = 0;
+       char debugdir[PATH_MAX];
+
+       snprintf(debugdir, sizeof(debugdir), "%s/%s", getenv("HOME"),
+                DEBUG_CACHE_DIR);
+
+       if (mkdir(debugdir, 0755) != 0 && errno != EEXIST)
+               return -1;
+
+       for (nd = rb_first(&session->machines); nd; nd = rb_next(nd)) {
+               struct machine *pos = rb_entry(nd, struct machine, rb_node);
+               ret |= __dsos__cache_build_ids(&pos->kernel_dsos, debugdir);
+               ret |= __dsos__cache_build_ids(&pos->user_dsos, debugdir);
+       }
+       return ret ? -1 : 0;
+}
+
+static bool dsos__read_build_ids(struct perf_header *self, bool with_hits)
+{
+       bool ret = false;
+       struct perf_session *session = container_of(self,
+                       struct perf_session, header);
+       struct rb_node *nd;
+
+       for (nd = rb_first(&session->machines); nd; nd = rb_next(nd)) {
+               struct machine *pos = rb_entry(nd, struct machine, rb_node);
+               ret |= __dsos__read_build_ids(&pos->kernel_dsos, with_hits);
+               ret |= __dsos__read_build_ids(&pos->user_dsos, with_hits);
+       }
+
+       return ret;
+}
+
+static int perf_header__adds_write(struct perf_header *self, int fd)
 {
-       LIST_HEAD(id_list);
        int nr_sections;
        struct perf_file_section *feat_sec;
        int sec_size;
        u64 sec_start;
-       int idx = 0;
+       int idx = 0, err;
 
-       if (fetch_build_id_table(&id_list))
+       if (dsos__read_build_ids(self, true))
                perf_header__set_feat(self, HEADER_BUILD_ID);
 
        nr_sections = bitmap_weight(self->adds_features, HEADER_FEAT_BITS);
        if (!nr_sections)
-               return;
+               return 0;
 
        feat_sec = calloc(sizeof(*feat_sec), nr_sections);
-       if (!feat_sec)
-               die("No memory");
+       if (feat_sec == NULL)
+               return -ENOMEM;
 
        sec_size = sizeof(*feat_sec) * nr_sections;
 
@@ -225,7 +436,6 @@ perf_header__adds_write(struct perf_header *self, int fd)
                trace_sec->size = lseek(fd, 0, SEEK_CUR) - trace_sec->offset;
        }
 
-
        if (perf_header__has_feat(self, HEADER_BUILD_ID)) {
                struct perf_file_section *buildid_sec;
 
@@ -233,21 +443,50 @@ perf_header__adds_write(struct perf_header *self, int fd)
 
                /* Write build-ids */
                buildid_sec->offset = lseek(fd, 0, SEEK_CUR);
-               write_buildid_table(fd, &id_list);
-               buildid_sec->size = lseek(fd, 0, SEEK_CUR) - buildid_sec->offset;
+               err = dsos__write_buildid_table(self, fd);
+               if (err < 0) {
+                       pr_debug("failed to write buildid table\n");
+                       goto out_free;
+               }
+               buildid_sec->size = lseek(fd, 0, SEEK_CUR) -
+                                         buildid_sec->offset;
+               dsos__cache_build_ids(self);
        }
 
        lseek(fd, sec_start, SEEK_SET);
-       do_write(fd, feat_sec, sec_size);
+       err = do_write(fd, feat_sec, sec_size);
+       if (err < 0)
+               pr_debug("failed to write feature section\n");
+out_free:
        free(feat_sec);
+       return err;
 }
 
-void perf_header__write(struct perf_header *self, int fd, bool at_exit)
+int perf_header__write_pipe(int fd)
+{
+       struct perf_pipe_file_header f_header;
+       int err;
+
+       f_header = (struct perf_pipe_file_header){
+               .magic     = PERF_MAGIC,
+               .size      = sizeof(f_header),
+       };
+
+       err = do_write(fd, &f_header, sizeof(f_header));
+       if (err < 0) {
+               pr_debug("failed to write perf pipe header\n");
+               return err;
+       }
+
+       return 0;
+}
+
+int perf_header__write(struct perf_header *self, int fd, bool at_exit)
 {
        struct perf_file_header f_header;
        struct perf_file_attr   f_attr;
        struct perf_header_attr *attr;
-       int i;
+       int i, err;
 
        lseek(fd, sizeof(f_header), SEEK_SET);
 
@@ -256,7 +495,11 @@ void perf_header__write(struct perf_header *self, int fd, bool at_exit)
                attr = self->attr[i];
 
                attr->id_offset = lseek(fd, 0, SEEK_CUR);
-               do_write(fd, attr->id, attr->ids * sizeof(u64));
+               err = do_write(fd, attr->id, attr->ids * sizeof(u64));
+               if (err < 0) {
+                       pr_debug("failed to write perf header\n");
+                       return err;
+               }
        }
 
 
@@ -272,18 +515,30 @@ void perf_header__write(struct perf_header *self, int fd, bool at_exit)
                                .size   = attr->ids * sizeof(u64),
                        }
                };
-               do_write(fd, &f_attr, sizeof(f_attr));
+               err = do_write(fd, &f_attr, sizeof(f_attr));
+               if (err < 0) {
+                       pr_debug("failed to write perf header attribute\n");
+                       return err;
+               }
        }
 
        self->event_offset = lseek(fd, 0, SEEK_CUR);
        self->event_size = event_count * sizeof(struct perf_trace_event_type);
-       if (events)
-               do_write(fd, events, self->event_size);
+       if (events) {
+               err = do_write(fd, events, self->event_size);
+               if (err < 0) {
+                       pr_debug("failed to write perf header events\n");
+                       return err;
+               }
+       }
 
        self->data_offset = lseek(fd, 0, SEEK_CUR);
 
-       if (at_exit)
-               perf_header__adds_write(self, fd);
+       if (at_exit) {
+               err = perf_header__adds_write(self, fd);
+               if (err < 0)
+                       return err;
+       }
 
        f_header = (struct perf_file_header){
                .magic     = PERF_MAGIC,
@@ -306,36 +561,39 @@ void perf_header__write(struct perf_header *self, int fd, bool at_exit)
        memcpy(&f_header.adds_features, &self->adds_features, sizeof(self->adds_features));
 
        lseek(fd, 0, SEEK_SET);
-       do_write(fd, &f_header, sizeof(f_header));
+       err = do_write(fd, &f_header, sizeof(f_header));
+       if (err < 0) {
+               pr_debug("failed to write perf header\n");
+               return err;
+       }
        lseek(fd, self->data_offset + self->data_size, SEEK_SET);
 
        self->frozen = 1;
+       return 0;
 }
 
-static void do_read(int fd, void *buf, size_t size)
+static int perf_header__getbuffer64(struct perf_header *self,
+                                   int fd, void *buf, size_t size)
 {
-       while (size) {
-               int ret = read(fd, buf, size);
+       if (do_read(fd, buf, size) <= 0)
+               return -1;
 
-               if (ret < 0)
-                       die("failed to read");
-               if (ret == 0)
-                       die("failed to read: missing data");
+       if (self->needs_swap)
+               mem_bswap_64(buf, size);
 
-               size -= ret;
-               buf += ret;
-       }
+       return 0;
 }
 
 int perf_header__process_sections(struct perf_header *self, int fd,
                                  int (*process)(struct perf_file_section *self,
+                                                struct perf_header *ph,
                                                 int feat, int fd))
 {
        struct perf_file_section *feat_sec;
        int nr_sections;
        int sec_size;
        int idx = 0;
-       int err = 0, feat = 1;
+       int err = -1, feat = 1;
 
        nr_sections = bitmap_weight(self->adds_features, HEADER_FEAT_BITS);
        if (!nr_sections)
@@ -349,33 +607,45 @@ int perf_header__process_sections(struct perf_header *self, int fd,
 
        lseek(fd, self->data_offset + self->data_size, SEEK_SET);
 
-       do_read(fd, feat_sec, sec_size);
+       if (perf_header__getbuffer64(self, fd, feat_sec, sec_size))
+               goto out_free;
 
+       err = 0;
        while (idx < nr_sections && feat < HEADER_LAST_FEATURE) {
                if (perf_header__has_feat(self, feat)) {
                        struct perf_file_section *sec = &feat_sec[idx++];
 
-                       err = process(sec, feat, fd);
+                       err = process(sec, self, feat, fd);
                        if (err < 0)
                                break;
                }
                ++feat;
        }
-
+out_free:
        free(feat_sec);
        return err;
-};
+}
 
 int perf_file_header__read(struct perf_file_header *self,
                           struct perf_header *ph, int fd)
 {
        lseek(fd, 0, SEEK_SET);
-       do_read(fd, self, sizeof(*self));
 
-       if (self->magic     != PERF_MAGIC ||
-           self->attr_size != sizeof(struct perf_file_attr))
+       if (do_read(fd, self, sizeof(*self)) <= 0 ||
+           memcmp(&self->magic, __perf_magic, sizeof(self->magic)))
                return -1;
 
+       if (self->attr_size != sizeof(struct perf_file_attr)) {
+               u64 attr_size = bswap_64(self->attr_size);
+
+               if (attr_size != sizeof(struct perf_file_attr))
+                       return -1;
+
+               mem_bswap_64(self, offsetof(struct perf_file_header,
+                                           adds_features));
+               ph->needs_swap = true;
+       }
+
        if (self->size != sizeof(*self)) {
                /* Support the previous format */
                if (self->size == offsetof(typeof(*self), adds_features))
@@ -385,19 +655,118 @@ int perf_file_header__read(struct perf_file_header *self,
        }
 
        memcpy(&ph->adds_features, &self->adds_features,
-              sizeof(self->adds_features));
+              sizeof(ph->adds_features));
+       /*
+        * FIXME: hack that assumes that if we need swap the perf.data file
+        * may be coming from an arch with a different word-size, ergo different
+        * DEFINE_BITMAP format, investigate more later, but for now its mostly
+        * safe to assume that we have a build-id section. Trace files probably
+        * have several other issues in this realm anyway...
+        */
+       if (ph->needs_swap) {
+               memset(&ph->adds_features, 0, sizeof(ph->adds_features));
+               perf_header__set_feat(ph, HEADER_BUILD_ID);
+       }
 
        ph->event_offset = self->event_types.offset;
-       ph->event_size   = self->event_types.size;
-       ph->data_offset  = self->data.offset;
+       ph->event_size   = self->event_types.size;
+       ph->data_offset  = self->data.offset;
        ph->data_size    = self->data.size;
        return 0;
 }
 
+static int __event_process_build_id(struct build_id_event *bev,
+                                   char *filename,
+                                   struct perf_session *session)
+{
+       int err = -1;
+       struct list_head *head;
+       struct machine *machine;
+       u16 misc;
+       struct dso *dso;
+       enum dso_kernel_type dso_type;
+
+       machine = perf_session__findnew_machine(session, bev->pid);
+       if (!machine)
+               goto out;
+
+       misc = bev->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
+
+       switch (misc) {
+       case PERF_RECORD_MISC_KERNEL:
+               dso_type = DSO_TYPE_KERNEL;
+               head = &machine->kernel_dsos;
+               break;
+       case PERF_RECORD_MISC_GUEST_KERNEL:
+               dso_type = DSO_TYPE_GUEST_KERNEL;
+               head = &machine->kernel_dsos;
+               break;
+       case PERF_RECORD_MISC_USER:
+       case PERF_RECORD_MISC_GUEST_USER:
+               dso_type = DSO_TYPE_USER;
+               head = &machine->user_dsos;
+               break;
+       default:
+               goto out;
+       }
+
+       dso = __dsos__findnew(head, filename);
+       if (dso != NULL) {
+               char sbuild_id[BUILD_ID_SIZE * 2 + 1];
+
+               dso__set_build_id(dso, &bev->build_id);
+
+               if (filename[0] == '[')
+                       dso->kernel = dso_type;
+
+               build_id__sprintf(dso->build_id, sizeof(dso->build_id),
+                                 sbuild_id);
+               pr_debug("build id event received for %s: %s\n",
+                        dso->long_name, sbuild_id);
+       }
+
+       err = 0;
+out:
+       return err;
+}
+
+static int perf_header__read_build_ids(struct perf_header *self,
+                       int input, u64 offset, u64 size)
+{
+       struct perf_session *session = container_of(self,
+                       struct perf_session, header);
+       struct build_id_event bev;
+       char filename[PATH_MAX];
+       u64 limit = offset + size;
+       int err = -1;
+
+       while (offset < limit) {
+               ssize_t len;
+
+               if (read(input, &bev, sizeof(bev)) != sizeof(bev))
+                       goto out;
+
+               if (self->needs_swap)
+                       perf_event_header__bswap(&bev.header);
+
+               len = bev.header.size - sizeof(bev);
+               if (read(input, filename, len) != len)
+                       goto out;
+
+               __event_process_build_id(&bev, filename, session);
+
+               offset += bev.header.size;
+       }
+       err = 0;
+out:
+       return err;
+}
+
 static int perf_file_section__process(struct perf_file_section *self,
+                                     struct perf_header *ph,
                                      int feat, int fd)
 {
-       if (lseek(fd, self->offset, SEEK_SET) < 0) {
+       if (lseek(fd, self->offset, SEEK_SET) == (off_t)-1) {
                pr_debug("Failed to lseek to %Ld offset for feature %d, "
                         "continuing...\n", self->offset, feat);
                return 0;
@@ -405,11 +774,11 @@ static int perf_file_section__process(struct perf_file_section *self,
 
        switch (feat) {
        case HEADER_TRACE_INFO:
-               trace_report(fd);
+               trace_report(fd, false);
                break;
 
        case HEADER_BUILD_ID:
-               if (perf_header__read_build_ids(fd, self->offset, self->size))
+               if (perf_header__read_build_ids(ph, fd, self->offset, self->size))
                        pr_debug("Failed to read buildids, continuing...\n");
                break;
        default:
@@ -419,19 +788,60 @@ static int perf_file_section__process(struct perf_file_section *self,
        return 0;
 }
 
-struct perf_header *perf_header__read(int fd)
+static int perf_file_header__read_pipe(struct perf_pipe_file_header *self,
+                                      struct perf_header *ph, int fd,
+                                      bool repipe)
 {
-       struct perf_header      *self = perf_header__new();
-       struct perf_file_header f_header;
+       if (do_read(fd, self, sizeof(*self)) <= 0 ||
+           memcmp(&self->magic, __perf_magic, sizeof(self->magic)))
+               return -1;
+
+       if (repipe && do_write(STDOUT_FILENO, self, sizeof(*self)) < 0)
+               return -1;
+
+       if (self->size != sizeof(*self)) {
+               u64 size = bswap_64(self->size);
+
+               if (size != sizeof(*self))
+                       return -1;
+
+               ph->needs_swap = true;
+       }
+
+       return 0;
+}
+
+static int perf_header__read_pipe(struct perf_session *session, int fd)
+{
+       struct perf_header *self = &session->header;
+       struct perf_pipe_file_header f_header;
+
+       if (perf_file_header__read_pipe(&f_header, self, fd,
+                                       session->repipe) < 0) {
+               pr_debug("incompatible file format\n");
+               return -EINVAL;
+       }
+
+       session->fd = fd;
+
+       return 0;
+}
+
+int perf_header__read(struct perf_session *session, int fd)
+{
+       struct perf_header *self = &session->header;
+       struct perf_file_header f_header;
        struct perf_file_attr   f_attr;
        u64                     f_id;
        int nr_attrs, nr_ids, i, j;
 
-       if (self == NULL)
-               die("nomem");
+       if (session->fd_pipe)
+               return perf_header__read_pipe(session, fd);
 
-       if (perf_file_header__read(&f_header, self, fd) < 0)
-               die("incompatible file format");
+       if (perf_file_header__read(&f_header, self, fd) < 0) {
+               pr_debug("incompatible file format\n");
+               return -EINVAL;
+       }
 
        nr_attrs = f_header.attrs.size / sizeof(f_attr);
        lseek(fd, f_header.attrs.offset, SEEK_SET);
@@ -440,24 +850,31 @@ struct perf_header *perf_header__read(int fd)
                struct perf_header_attr *attr;
                off_t tmp;
 
-               do_read(fd, &f_attr, sizeof(f_attr));
+               if (perf_header__getbuffer64(self, fd, &f_attr, sizeof(f_attr)))
+                       goto out_errno;
+
                tmp = lseek(fd, 0, SEEK_CUR);
 
                attr = perf_header_attr__new(&f_attr.attr);
                if (attr == NULL)
-                        die("nomem");
+                        return -ENOMEM;
 
                nr_ids = f_attr.ids.size / sizeof(u64);
                lseek(fd, f_attr.ids.offset, SEEK_SET);
 
                for (j = 0; j < nr_ids; j++) {
-                       do_read(fd, &f_id, sizeof(f_id));
+                       if (perf_header__getbuffer64(self, fd, &f_id, sizeof(f_id)))
+                               goto out_errno;
 
-                       if (perf_header_attr__add_id(attr, f_id) < 0)
-                               die("nomem");
+                       if (perf_header_attr__add_id(attr, f_id) < 0) {
+                               perf_header_attr__delete(attr);
+                               return -ENOMEM;
+                       }
+               }
+               if (perf_header__add_attr(self, attr) < 0) {
+                       perf_header_attr__delete(attr);
+                       return -ENOMEM;
                }
-               if (perf_header__add_attr(self, attr) < 0)
-                        die("nomem");
 
                lseek(fd, tmp, SEEK_SET);
        }
@@ -465,9 +882,11 @@ struct perf_header *perf_header__read(int fd)
        if (f_header.event_types.size) {
                lseek(fd, f_header.event_types.offset, SEEK_SET);
                events = malloc(f_header.event_types.size);
-               if (!events)
-                       die("nomem");
-               do_read(fd, events, f_header.event_types.size);
+               if (events == NULL)
+                       return -ENOMEM;
+               if (perf_header__getbuffer64(self, fd, events,
+                                            f_header.event_types.size))
+                       goto out_errno;
                event_count =  f_header.event_types.size / sizeof(struct perf_trace_event_type);
        }
 
@@ -476,8 +895,9 @@ struct perf_header *perf_header__read(int fd)
        lseek(fd, self->data_offset, SEEK_SET);
 
        self->frozen = 1;
-
-       return self;
+       return 0;
+out_errno:
+       return -errno;
 }
 
 u64 perf_header__sample_type(struct perf_header *header)
@@ -502,6 +922,14 @@ perf_header__find_attr(u64 id, struct perf_header *header)
 {
        int i;
 
+       /*
+        * We set id to -1 if the data file doesn't contain sample
+        * ids. Check for this and avoid walking through the entire
+        * list of ids which may be large.
+        */
+       if (id == -1ULL)
+               return NULL;
+
        for (i = 0; i < header->attrs; i++) {
                struct perf_header_attr *attr = header->attr[i];
                int j;
@@ -514,3 +942,231 @@ perf_header__find_attr(u64 id, struct perf_header *header)
 
        return NULL;
 }
+
+int event__synthesize_attr(struct perf_event_attr *attr, u16 ids, u64 *id,
+                          event__handler_t process,
+                          struct perf_session *session)
+{
+       event_t *ev;
+       size_t size;
+       int err;
+
+       size = sizeof(struct perf_event_attr);
+       size = ALIGN(size, sizeof(u64));
+       size += sizeof(struct perf_event_header);
+       size += ids * sizeof(u64);
+
+       ev = malloc(size);
+
+       ev->attr.attr = *attr;
+       memcpy(ev->attr.id, id, ids * sizeof(u64));
+
+       ev->attr.header.type = PERF_RECORD_HEADER_ATTR;
+       ev->attr.header.size = size;
+
+       err = process(ev, session);
+
+       free(ev);
+
+       return err;
+}
+
+int event__synthesize_attrs(struct perf_header *self,
+                           event__handler_t process,
+                           struct perf_session *session)
+{
+       struct perf_header_attr *attr;
+       int i, err = 0;
+
+       for (i = 0; i < self->attrs; i++) {
+               attr = self->attr[i];
+
+               err = event__synthesize_attr(&attr->attr, attr->ids, attr->id,
+                                            process, session);
+               if (err) {
+                       pr_debug("failed to create perf header attribute\n");
+                       return err;
+               }
+       }
+
+       return err;
+}
+
+int event__process_attr(event_t *self, struct perf_session *session)
+{
+       struct perf_header_attr *attr;
+       unsigned int i, ids, n_ids;
+
+       attr = perf_header_attr__new(&self->attr.attr);
+       if (attr == NULL)
+               return -ENOMEM;
+
+       ids = self->header.size;
+       ids -= (void *)&self->attr.id - (void *)self;
+       n_ids = ids / sizeof(u64);
+
+       for (i = 0; i < n_ids; i++) {
+               if (perf_header_attr__add_id(attr, self->attr.id[i]) < 0) {
+                       perf_header_attr__delete(attr);
+                       return -ENOMEM;
+               }
+       }
+
+       if (perf_header__add_attr(&session->header, attr) < 0) {
+               perf_header_attr__delete(attr);
+               return -ENOMEM;
+       }
+
+       perf_session__update_sample_type(session);
+
+       return 0;
+}
+
+int event__synthesize_event_type(u64 event_id, char *name,
+                                event__handler_t process,
+                                struct perf_session *session)
+{
+       event_t ev;
+       size_t size = 0;
+       int err = 0;
+
+       memset(&ev, 0, sizeof(ev));
+
+       ev.event_type.event_type.event_id = event_id;
+       memset(ev.event_type.event_type.name, 0, MAX_EVENT_NAME);
+       strncpy(ev.event_type.event_type.name, name, MAX_EVENT_NAME - 1);
+
+       ev.event_type.header.type = PERF_RECORD_HEADER_EVENT_TYPE;
+       size = strlen(name);
+       size = ALIGN(size, sizeof(u64));
+       ev.event_type.header.size = sizeof(ev.event_type) -
+               (sizeof(ev.event_type.event_type.name) - size);
+
+       err = process(&ev, session);
+
+       return err;
+}
+
+int event__synthesize_event_types(event__handler_t process,
+                                 struct perf_session *session)
+{
+       struct perf_trace_event_type *type;
+       int i, err = 0;
+
+       for (i = 0; i < event_count; i++) {
+               type = &events[i];
+
+               err = event__synthesize_event_type(type->event_id, type->name,
+                                                  process, session);
+               if (err) {
+                       pr_debug("failed to create perf header event type\n");
+                       return err;
+               }
+       }
+
+       return err;
+}
+
+int event__process_event_type(event_t *self,
+                             struct perf_session *session __unused)
+{
+       if (perf_header__push_event(self->event_type.event_type.event_id,
+                                   self->event_type.event_type.name) < 0)
+               return -ENOMEM;
+
+       return 0;
+}
+
+int event__synthesize_tracing_data(int fd, struct perf_event_attr *pattrs,
+                                  int nb_events,
+                                  event__handler_t process,
+                                  struct perf_session *session __unused)
+{
+       event_t ev;
+       ssize_t size = 0, aligned_size = 0, padding;
+       int err = 0;
+
+       memset(&ev, 0, sizeof(ev));
+
+       ev.tracing_data.header.type = PERF_RECORD_HEADER_TRACING_DATA;
+       size = read_tracing_data_size(fd, pattrs, nb_events);
+       if (size <= 0)
+               return size;
+       aligned_size = ALIGN(size, sizeof(u64));
+       padding = aligned_size - size;
+       ev.tracing_data.header.size = sizeof(ev.tracing_data);
+       ev.tracing_data.size = aligned_size;
+
+       process(&ev, session);
+
+       err = read_tracing_data(fd, pattrs, nb_events);
+       write_padded(fd, NULL, 0, padding);
+
+       return aligned_size;
+}
+
+int event__process_tracing_data(event_t *self,
+                               struct perf_session *session)
+{
+       ssize_t size_read, padding, size = self->tracing_data.size;
+       off_t offset = lseek(session->fd, 0, SEEK_CUR);
+       char buf[BUFSIZ];
+
+       /* setup for reading amidst mmap */
+       lseek(session->fd, offset + sizeof(struct tracing_data_event),
+             SEEK_SET);
+
+       size_read = trace_report(session->fd, session->repipe);
+
+       padding = ALIGN(size_read, sizeof(u64)) - size_read;
+
+       if (read(session->fd, buf, padding) < 0)
+               die("reading input file");
+       if (session->repipe) {
+               int retw = write(STDOUT_FILENO, buf, padding);
+               if (retw <= 0 || retw != padding)
+                       die("repiping tracing data padding");
+       }
+
+       if (size_read + padding != size)
+               die("tracing data size mismatch");
+
+       return size_read + padding;
+}
+
+int event__synthesize_build_id(struct dso *pos, u16 misc,
+                              event__handler_t process,
+                              struct machine *machine,
+                              struct perf_session *session)
+{
+       event_t ev;
+       size_t len;
+       int err = 0;
+
+       if (!pos->hit)
+               return err;
+
+       memset(&ev, 0, sizeof(ev));
+
+       len = pos->long_name_len + 1;
+       len = ALIGN(len, NAME_ALIGN);
+       memcpy(&ev.build_id.build_id, pos->build_id, sizeof(pos->build_id));
+       ev.build_id.header.type = PERF_RECORD_HEADER_BUILD_ID;
+       ev.build_id.header.misc = misc;
+       ev.build_id.pid = machine->pid;
+       ev.build_id.header.size = sizeof(ev.build_id) + len;
+       memcpy(&ev.build_id.filename, pos->long_name, pos->long_name_len);
+
+       err = process(&ev, session);
+
+       return err;
+}
+
+int event__process_build_id(event_t *self,
+                           struct perf_session *session)
+{
+       __event_process_build_id(&self->build_id,
+                                self->build_id.filename,
+                                session);
+       return 0;
+}