Merge tag 'perf-core-for-mingo-4.11-20170126' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core

Pull the latest perf/core updates from Arnaldo Carvalho de Melo:

New features:

 - Introduce 'perf ftrace' a perf front end to the kernel's ftrace
   function and function_graph tracer, defaulting to the "function_graph"
   tracer, more work will be done in reviving this effort, forward porting
   it from its initial patch submission (Namhyung Kim)

 - Add 'e' and 'c' hotkeys to expand/collapse call chains for a single
   hist entry in the 'perf report' and 'perf top' TUI (Jiri Olsa)

Fixes:

 - Fix wrong register name for arm64, used in 'perf probe' (He Kuang)

 - Fix map offsets in relocation in libbpf (Joe Stringer)

 - Fix looking up dwarf unwind stack info (Matija Glavinic Pecotic)

Infrastructure changes:

 - libbpf prog functions sync with what is exported via uapi (Joe Stringer)

Trivial changes:

 - Remove unnecessary checks and assignments in 'perf probe's
   try_to_find_absolute_address() (Markus Elfring)

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

20 files changed, 546 insertions, 67 deletions

diff --git a/tools/perf/Build b/tools/perf/Build
index 7039ecb89170..9b79f8d7db50 100644
--- a/tools/perf/Build
+++ b/tools/perf/Build
@@ -3,6 +3,7 @@ perf-y += builtin-annotate.o
 perf-y += builtin-config.o
 perf-y += builtin-diff.o
 perf-y += builtin-evlist.o
+perf-y += builtin-ftrace.o
 perf-y += builtin-help.o
 perf-y += builtin-sched.o
 perf-y += builtin-buildid-list.o
diff --git a/tools/perf/Documentation/perf-c2c.txt b/tools/perf/Documentation/perf-c2c.txt
index 3f06730c7f47..2da07e51e119 100644
--- a/tools/perf/Documentation/perf-c2c.txt
+++ b/tools/perf/Documentation/perf-c2c.txt
@@ -248,7 +248,7 @@ output fields set for caheline offsets output:
              Code address, Code symbol, Shared Object, Source line
   dso   - coalesced by shared object
 
-By default the coalescing is setup with 'pid,tid,iaddr'.
+By default the coalescing is setup with 'pid,iaddr'.
 
 STDIO OUTPUT
 ------------
diff --git a/tools/perf/Documentation/perf-ftrace.txt b/tools/perf/Documentation/perf-ftrace.txt
new file mode 100644
index 000000000000..2d96de6132a9
--- /dev/null
+++ b/tools/perf/Documentation/perf-ftrace.txt
@@ -0,0 +1,36 @@
+perf-ftrace(1)
+=============
+
+NAME
+----
+perf-ftrace - simple wrapper for kernel's ftrace functionality
+
+
+SYNOPSIS
+--------
+[verse]
+'perf ftrace' <command>
+
+DESCRIPTION
+-----------
+The 'perf ftrace' command is a simple wrapper of kernel's ftrace
+functionality.  It only supports single thread tracing currently and
+just reads trace_pipe in text and then write it to stdout.
+
+The following options apply to perf ftrace.
+
+OPTIONS
+-------
+
+-t::
+--tracer=::
+        Tracer to use: function_graph or function.
+
+-v::
+--verbose=::
+        Verbosity level.
+
+
+SEE ALSO
+--------
+linkperf:perf-record[1], linkperf:perf-trace[1]
diff --git a/tools/perf/arch/arm64/include/dwarf-regs-table.h b/tools/perf/arch/arm64/include/dwarf-regs-table.h
index 26759363f921..36e375f5a211 100644
--- a/tools/perf/arch/arm64/include/dwarf-regs-table.h
+++ b/tools/perf/arch/arm64/include/dwarf-regs-table.h
@@ -2,12 +2,12 @@
 /* This is included in perf/util/dwarf-regs.c */
 
 static const char * const aarch64_regstr_tbl[] = {
-        "%r0", "%r1", "%r2", "%r3", "%r4",
-        "%r5", "%r6", "%r7", "%r8", "%r9",
-        "%r10", "%r11", "%r12", "%r13", "%r14",
-        "%r15", "%r16", "%r17", "%r18", "%r19",
-        "%r20", "%r21", "%r22", "%r23", "%r24",
-        "%r25", "%r26", "%r27", "%r28", "%r29",
+        "%x0", "%x1", "%x2", "%x3", "%x4",
+        "%x5", "%x6", "%x7", "%x8", "%x9",
+        "%x10", "%x11", "%x12", "%x13", "%x14",
+        "%x15", "%x16", "%x17", "%x18", "%x19",
+        "%x20", "%x21", "%x22", "%x23", "%x24",
+        "%x25", "%x26", "%x27", "%x28", "%x29",
         "%lr", "%sp",
 };
 #endif
diff --git a/tools/perf/builtin-c2c.c b/tools/perf/builtin-c2c.c
index f8ca7a4ebabc..e2b21723bbf8 100644
--- a/tools/perf/builtin-c2c.c
+++ b/tools/perf/builtin-c2c.c
@@ -58,7 +58,7 @@ struct c2c_hist_entry {
         struct hist_entry       he;
 };
 
-static char const *coalesce_default = "pid,tid,iaddr";
+static char const *coalesce_default = "pid,iaddr";
 
 struct perf_c2c {
         struct perf_tool        tool;
@@ -2476,6 +2476,7 @@ static int build_cl_output(char *cl_sort, bool no_source)
                 "mean_rmt,"
                 "mean_lcl,"
                 "mean_load,"
+                "tot_recs,"
                 "cpucnt,",
                 add_sym ? "symbol," : "",
                 add_dso ? "dso," : "",
diff --git a/tools/perf/builtin-ftrace.c b/tools/perf/builtin-ftrace.c
new file mode 100644
index 000000000000..d05658d2b8f1
--- /dev/null
+++ b/tools/perf/builtin-ftrace.c
@@ -0,0 +1,243 @@
+/*
+ * builtin-ftrace.c
+ *
+ * Copyright (c) 2013  LG Electronics,  Namhyung Kim <namhyung@kernel.org>
+ *
+ * Released under the GPL v2.
+ */
+
+#include "builtin.h"
+#include "perf.h"
+
+#include <unistd.h>
+#include <signal.h>
+
+#include "debug.h"
+#include <subcmd/parse-options.h>
+#include "evlist.h"
+#include "target.h"
+#include "thread_map.h"
+
+
+#define DEFAULT_TRACER  "function_graph"
+
+struct perf_ftrace {
+        struct perf_evlist *evlist;
+        struct target target;
+        const char *tracer;
+};
+
+static bool done;
+
+static void sig_handler(int sig __maybe_unused)
+{
+        done = true;
+}
+
+/*
+ * perf_evlist__prepare_workload will send a SIGUSR1 if the fork fails, since
+ * we asked by setting its exec_error to the function below,
+ * ftrace__workload_exec_failed_signal.
+ *
+ * XXX We need to handle this more appropriately, emitting an error, etc.
+ */
+static void ftrace__workload_exec_failed_signal(int signo __maybe_unused,
+                                                siginfo_t *info __maybe_unused,
+                                                void *ucontext __maybe_unused)
+{
+        /* workload_exec_errno = info->si_value.sival_int; */
+        done = true;
+}
+
+static int write_tracing_file(const char *name, const char *val)
+{
+        char *file;
+        int fd, ret = -1;
+        ssize_t size = strlen(val);
+
+        file = get_tracing_file(name);
+        if (!file) {
+                pr_debug("cannot get tracing file: %s\n", name);
+                return -1;
+        }
+
+        fd = open(file, O_WRONLY);
+        if (fd < 0) {
+                pr_debug("cannot open tracing file: %s\n", name);
+                goto out;
+        }
+
+        if (write(fd, val, size) == size)
+                ret = 0;
+        else
+                pr_debug("write '%s' to tracing/%s failed\n", val, name);
+
+        close(fd);
+out:
+        put_tracing_file(file);
+        return ret;
+}
+
+static int reset_tracing_files(struct perf_ftrace *ftrace __maybe_unused)
+{
+        if (write_tracing_file("tracing_on", "0") < 0)
+                return -1;
+
+        if (write_tracing_file("current_tracer", "nop") < 0)
+                return -1;
+
+        if (write_tracing_file("set_ftrace_pid", " ") < 0)
+                return -1;
+
+        return 0;
+}
+
+static int __cmd_ftrace(struct perf_ftrace *ftrace, int argc, const char **argv)
+{
+        char *trace_file;
+        int trace_fd;
+        char *trace_pid;
+        char buf[4096];
+        struct pollfd pollfd = {
+                .events = POLLIN,
+        };
+
+        if (geteuid() != 0) {
+                pr_err("ftrace only works for root!\n");
+                return -1;
+        }
+
+        if (argc < 1)
+                return -1;
+
+        signal(SIGINT, sig_handler);
+        signal(SIGUSR1, sig_handler);
+        signal(SIGCHLD, sig_handler);
+
+        reset_tracing_files(ftrace);
+
+        /* reset ftrace buffer */
+        if (write_tracing_file("trace", "0") < 0)
+                goto out;
+
+        if (perf_evlist__prepare_workload(ftrace->evlist, &ftrace->target,
+                                          argv, false, ftrace__workload_exec_failed_signal) < 0)
+                goto out;
+
+        if (write_tracing_file("current_tracer", ftrace->tracer) < 0) {
+                pr_err("failed to set current_tracer to %s\n", ftrace->tracer);
+                goto out;
+        }
+
+        if (asprintf(&trace_pid, "%d", thread_map__pid(ftrace->evlist->threads, 0)) < 0) {
+                pr_err("failed to allocate pid string\n");
+                goto out;
+        }
+
+        if (write_tracing_file("set_ftrace_pid", trace_pid) < 0) {
+                pr_err("failed to set pid: %s\n", trace_pid);
+                goto out_free_pid;
+        }
+
+        trace_file = get_tracing_file("trace_pipe");
+        if (!trace_file) {
+                pr_err("failed to open trace_pipe\n");
+                goto out_free_pid;
+        }
+
+        trace_fd = open(trace_file, O_RDONLY);
+
+        put_tracing_file(trace_file);
+
+        if (trace_fd < 0) {
+                pr_err("failed to open trace_pipe\n");
+                goto out_free_pid;
+        }
+
+        fcntl(trace_fd, F_SETFL, O_NONBLOCK);
+        pollfd.fd = trace_fd;
+
+        if (write_tracing_file("tracing_on", "1") < 0) {
+                pr_err("can't enable tracing\n");
+                goto out_close_fd;
+        }
+
+        perf_evlist__start_workload(ftrace->evlist);
+
+        while (!done) {
+                if (poll(&pollfd, 1, -1) < 0)
+                        break;
+
+                if (pollfd.revents & POLLIN) {
+                        int n = read(trace_fd, buf, sizeof(buf));
+                        if (n < 0)
+                                break;
+                        if (fwrite(buf, n, 1, stdout) != 1)
+                                break;
+                }
+        }
+
+        write_tracing_file("tracing_on", "0");
+
+        /* read remaining buffer contents */
+        while (true) {
+                int n = read(trace_fd, buf, sizeof(buf));
+                if (n <= 0)
+                        break;
+                if (fwrite(buf, n, 1, stdout) != 1)
+                        break;
+        }
+
+out_close_fd:
+        close(trace_fd);
+out_free_pid:
+        free(trace_pid);
+out:
+        reset_tracing_files(ftrace);
+
+        return done ? 0 : -1;
+}
+
+int cmd_ftrace(int argc, const char **argv, const char *prefix __maybe_unused)
+{
+        int ret;
+        struct perf_ftrace ftrace = {
+                .tracer = "function_graph",
+                .target = { .uid = UINT_MAX, },
+        };
+        const char * const ftrace_usage[] = {
+                "perf ftrace [<options>] <command>",
+                "perf ftrace [<options>] -- <command> [<options>]",
+                NULL
+        };
+        const struct option ftrace_options[] = {
+        OPT_STRING('t', "tracer", &ftrace.tracer, "tracer",
+                   "tracer to use: function_graph(default) or function"),
+        OPT_INCR('v', "verbose", &verbose,
+                 "be more verbose"),
+        OPT_END()
+        };
+
+        argc = parse_options(argc, argv, ftrace_options, ftrace_usage,
+                            PARSE_OPT_STOP_AT_NON_OPTION);
+        if (!argc)
+                usage_with_options(ftrace_usage, ftrace_options);
+
+        ftrace.evlist = perf_evlist__new();
+        if (ftrace.evlist == NULL)
+                return -ENOMEM;
+
+        ret = perf_evlist__create_maps(ftrace.evlist, &ftrace.target);
+        if (ret < 0)
+                goto out_delete_evlist;
+
+        if (ftrace.tracer == NULL)
+                ftrace.tracer = DEFAULT_TRACER;
+
+        ret = __cmd_ftrace(&ftrace, argc, argv);
+
+out_delete_evlist:
+        perf_evlist__delete(ftrace.evlist);
+
+        return ret;
+}
diff --git a/tools/perf/builtin.h b/tools/perf/builtin.h
index b55f5be486a1..036e1e35b1a8 100644
--- a/tools/perf/builtin.h
+++ b/tools/perf/builtin.h
@@ -41,6 +41,7 @@ int cmd_trace(int argc, const char **argv, const char *prefix);
 int cmd_inject(int argc, const char **argv, const char *prefix);
 int cmd_mem(int argc, const char **argv, const char *prefix);
 int cmd_data(int argc, const char **argv, const char *prefix);
+int cmd_ftrace(int argc, const char **argv, const char *prefix);
 
 int find_scripts(char **scripts_array, char **scripts_path_array);
 #endif
diff --git a/tools/perf/command-list.txt b/tools/perf/command-list.txt
index fb45613dba9e..ac3efd396a72 100644
--- a/tools/perf/command-list.txt
+++ b/tools/perf/command-list.txt
@@ -11,6 +11,7 @@ perf-data			mainporcelain common
 perf-diff                       mainporcelain common
 perf-config                     mainporcelain common
 perf-evlist                     mainporcelain common
+perf-ftrace                     mainporcelain common
 perf-inject                     mainporcelain common
 perf-kallsyms                   mainporcelain common
 perf-kmem                       mainporcelain common
diff --git a/tools/perf/perf.c b/tools/perf/perf.c
index 0324cd15e42a..34bcf90f8871 100644
--- a/tools/perf/perf.c
+++ b/tools/perf/perf.c
@@ -71,6 +71,7 @@ static struct cmd_struct commands[] = {
         { "inject",     cmd_inject,     0 },
         { "mem",        cmd_mem,        0 },
         { "data",       cmd_data,       0 },
+        { "ftrace",     cmd_ftrace,     0 },
 };
 
 struct pager_config {
diff --git a/tools/perf/tests/llvm.c b/tools/perf/tests/llvm.c
index 02a33ebcd992..d357dab72e68 100644
--- a/tools/perf/tests/llvm.c
+++ b/tools/perf/tests/llvm.c
@@ -13,7 +13,7 @@ static int test__bpf_parsing(void *obj_buf, size_t obj_buf_sz)
         struct bpf_object *obj;
 
         obj = bpf_object__open_buffer(obj_buf, obj_buf_sz, NULL);
-        if (IS_ERR(obj))
+        if (libbpf_get_error(obj))
                 return TEST_FAIL;
         bpf_object__close(obj);
         return TEST_OK;
diff --git a/tools/perf/ui/browsers/hists.c b/tools/perf/ui/browsers/hists.c
index 641b40234a9d..fc4fb669ceee 100644
--- a/tools/perf/ui/browsers/hists.c
+++ b/tools/perf/ui/browsers/hists.c
@@ -501,8 +501,8 @@ static int hierarchy_set_folding(struct hist_browser *hb, struct hist_entry *he,
         return n;
 }
 
-static void hist_entry__set_folding(struct hist_entry *he,
-                                    struct hist_browser *hb, bool unfold)
+static void __hist_entry__set_folding(struct hist_entry *he,
+                                      struct hist_browser *hb, bool unfold)
 {
         hist_entry__init_have_children(he);
         he->unfolded = unfold ? he->has_children : false;
@@ -520,12 +520,34 @@ static void hist_entry__set_folding(struct hist_entry *he,
                 he->nr_rows = 0;
 }
 
+static void hist_entry__set_folding(struct hist_entry *he,
+                                    struct hist_browser *browser, bool unfold)
+{
+        double percent;
+
+        percent = hist_entry__get_percent_limit(he);
+        if (he->filtered || percent < browser->min_pcnt)
+                return;
+
+        __hist_entry__set_folding(he, browser, unfold);
+
+        if (!he->depth || unfold)
+                browser->nr_hierarchy_entries++;
+        if (he->leaf)
+                browser->nr_callchain_rows += he->nr_rows;
+        else if (unfold && !hist_entry__has_hierarchy_children(he, browser->min_pcnt)) {
+                browser->nr_hierarchy_entries++;
+                he->has_no_entry = true;
+                he->nr_rows = 1;
+        } else
+                he->has_no_entry = false;
+}
+
 static void
 __hist_browser__set_folding(struct hist_browser *browser, bool unfold)
 {
         struct rb_node *nd;
         struct hist_entry *he;
-        double percent;
 
         nd = rb_first(&browser->hists->entries);
         while (nd) {
@@ -535,21 +557,6 @@ __hist_browser__set_folding(struct hist_browser *browser, bool unfold)
                 nd = __rb_hierarchy_next(nd, HMD_FORCE_CHILD);
 
                 hist_entry__set_folding(he, browser, unfold);
-
-                percent = hist_entry__get_percent_limit(he);
-                if (he->filtered || percent < browser->min_pcnt)
-                        continue;
-
-                if (!he->depth || unfold)
-                        browser->nr_hierarchy_entries++;
-                if (he->leaf)
-                        browser->nr_callchain_rows += he->nr_rows;
-                else if (unfold && !hist_entry__has_hierarchy_children(he, browser->min_pcnt)) {
-                        browser->nr_hierarchy_entries++;
-                        he->has_no_entry = true;
-                        he->nr_rows = 1;
-                } else
-                        he->has_no_entry = false;
         }
 }
 
@@ -564,6 +571,15 @@ static void hist_browser__set_folding(struct hist_browser *browser, bool unfold)
         ui_browser__reset_index(&browser->b);
 }
 
+static void hist_browser__set_folding_selected(struct hist_browser *browser, bool unfold)
+{
+        if (!browser->he_selection)
+                return;
+
+        hist_entry__set_folding(browser->he_selection, browser, unfold);
+        browser->b.nr_entries = hist_browser__nr_entries(browser);
+}
+
 static void ui_browser__warn_lost_events(struct ui_browser *browser)
 {
         ui_browser__warning(browser, 4,
@@ -637,10 +653,18 @@ int hist_browser__run(struct hist_browser *browser, const char *help)
                         /* Collapse the whole world. */
                         hist_browser__set_folding(browser, false);
                         break;
+                case 'c':
+                        /* Collapse the selected entry. */
+                        hist_browser__set_folding_selected(browser, false);
+                        break;
                 case 'E':
                         /* Expand the whole world. */
                         hist_browser__set_folding(browser, true);
                         break;
+                case 'e':
+                        /* Expand the selected entry. */
+                        hist_browser__set_folding_selected(browser, true);
+                        break;
                 case 'H':
                         browser->show_headers = !browser->show_headers;
                         hist_browser__update_rows(browser);
diff --git a/tools/perf/util/dso.c b/tools/perf/util/dso.c
index d2c6cdd9d42b..28d41e709128 100644
--- a/tools/perf/util/dso.c
+++ b/tools/perf/util/dso.c
@@ -9,6 +9,13 @@
 #include "debug.h"
 #include "vdso.h"
 
+static const char * const debuglink_paths[] = {
+        "%.0s%s",
+        "%s/%s",
+        "%s/.debug/%s",
+        "/usr/lib/debug%s/%s"
+};
+
 char dso__symtab_origin(const struct dso *dso)
 {
         static const char origin[] = {
@@ -44,24 +51,43 @@ int dso__read_binary_type_filename(const struct dso *dso,
         size_t len;
 
         switch (type) {
-        case DSO_BINARY_TYPE__DEBUGLINK: {
-                char *debuglink;
+        case DSO_BINARY_TYPE__DEBUGLINK:
+        {
+                const char *last_slash;
+                char dso_dir[PATH_MAX];
+                char symfile[PATH_MAX];
+                unsigned int i;
 
                 len = __symbol__join_symfs(filename, size, dso->long_name);
-                debuglink = filename + len;
-                while (debuglink != filename && *debuglink != '/')
-                        debuglink--;
-                if (*debuglink == '/')
-                        debuglink++;
+                last_slash = filename + len;
+                while (last_slash != filename && *last_slash != '/')
+                        last_slash--;
 
-                ret = -1;
-                if (!is_regular_file(filename))
+                strncpy(dso_dir, filename, last_slash - filename);
+                dso_dir[last_slash-filename] = '\0';
+
+                if (!is_regular_file(filename)) {
+                        ret = -1;
+                        break;
+                }
+
+                ret = filename__read_debuglink(filename, symfile, PATH_MAX);
+                if (ret)
                         break;
 
-                ret = filename__read_debuglink(filename, debuglink,
-                                               size - (debuglink - filename));
+                /* Check predefined locations where debug file might reside */
+                ret = -1;
+                for (i = 0; i < ARRAY_SIZE(debuglink_paths); i++) {
+                        snprintf(filename, size,
+                                        debuglink_paths[i], dso_dir, symfile);
+                        if (is_regular_file(filename)) {
+                                ret = 0;
+                                break;
+                        }
                 }
+
                 break;
+        }
         case DSO_BINARY_TYPE__BUILD_ID_CACHE:
                 if (dso__build_id_filename(dso, filename, size) == NULL)
                         ret = -1;
diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index 00fd8a8850d3..c567d9f0aa92 100644
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -2803,8 +2803,10 @@ static int perf_evsel__prepare_tracepoint_event(struct perf_evsel *evsel,
         }
 
         event = pevent_find_event(pevent, evsel->attr.config);
-        if (event == NULL)
+        if (event == NULL) {
+                pr_debug("cannot find event format for %d\n", (int)evsel->attr.config);
                 return -1;
+        }
 
         if (!evsel->name) {
                 snprintf(bf, sizeof(bf), "%s:%s", event->system, event->name);
diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index 6a6f44dd594b..2c1bca240597 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -3023,20 +3023,17 @@ static int try_to_find_absolute_address(struct perf_probe_event *pev,
 
         tev->nargs = pev->nargs;
         tev->args = zalloc(sizeof(struct probe_trace_arg) * tev->nargs);
-        if (!tev->args) {
-                err = -ENOMEM;
+        if (!tev->args)
                 goto errout;
-        }
+
         for (i = 0; i < tev->nargs; i++)
                 copy_to_probe_trace_arg(&tev->args[i], &pev->args[i]);
 
         return 1;
 
 errout:
-        if (*tevs) {
-                clear_probe_trace_events(*tevs, 1);
-                *tevs = NULL;
-        }
+        clear_probe_trace_events(*tevs, 1);
+        *tevs = NULL;
         return err;
 }
 
diff --git a/tools/perf/util/scripting-engines/trace-event-perl.c b/tools/perf/util/scripting-engines/trace-event-perl.c
index e55a132f69b7..014ecd6f67c4 100644
--- a/tools/perf/util/scripting-engines/trace-event-perl.c
+++ b/tools/perf/util/scripting-engines/trace-event-perl.c
@@ -350,8 +350,10 @@ static void perl_process_tracepoint(struct perf_sample *sample,
         if (evsel->attr.type != PERF_TYPE_TRACEPOINT)
                 return;
 
-        if (!event)
-                die("ug! no event found for type %" PRIu64, (u64)evsel->attr.config);
+        if (!event) {
+                pr_debug("ug! no event found for type %" PRIu64, (u64)evsel->attr.config);
+                return;
+        }
 
         pid = raw_field_value(event, "common_pid", data);
 
diff --git a/tools/perf/util/trace-event-info.c b/tools/perf/util/trace-event-info.c
index d995743cb673..ceb0e2720223 100644
--- a/tools/perf/util/trace-event-info.c
+++ b/tools/perf/util/trace-event-info.c
@@ -42,7 +42,7 @@
 #include "evsel.h"
 #include "debug.h"
 
-#define VERSION "0.5"
+#define VERSION "0.6"
 
 static int output_fd;
 
@@ -379,6 +379,34 @@ out:
         return err;
 }
 
+static int record_saved_cmdline(void)
+{
+        unsigned int size;
+        char *path;
+        struct stat st;
+        int ret, err = 0;
+
+        path = get_tracing_file("saved_cmdlines");
+        if (!path) {
+                pr_debug("can't get tracing/saved_cmdline");
+                return -ENOMEM;
+        }
+
+        ret = stat(path, &st);
+        if (ret < 0) {
+                /* not found */
+                size = 0;
+                if (write(output_fd, &size, 8) != 8)
+                        err = -EIO;
+                goto out;
+        }
+        err = record_file(path, 8);
+
+out:
+        put_tracing_file(path);
+        return err;
+}
+
 static void
 put_tracepoints_path(struct tracepoint_path *tps)
 {
@@ -539,6 +567,9 @@ struct tracing_data *tracing_data_get(struct list_head *pattrs,
         if (err)
                 goto out;
         err = record_ftrace_printk();
+        if (err)
+                goto out;
+        err = record_saved_cmdline();
 
 out:
         /*
diff --git a/tools/perf/util/trace-event-parse.c b/tools/perf/util/trace-event-parse.c
index 33b52eaa39db..de0078e21408 100644
--- a/tools/perf/util/trace-event-parse.c
+++ b/tools/perf/util/trace-event-parse.c
@@ -160,6 +160,23 @@ void parse_ftrace_printk(struct pevent *pevent,
         }
 }
 
+void parse_saved_cmdline(struct pevent *pevent,
+                         char *file, unsigned int size __maybe_unused)
+{
+        char *comm;
+        char *line;
+        char *next = NULL;
+        int pid;
+
+        line = strtok_r(file, "\n", &next);
+        while (line) {
+                sscanf(line, "%d %ms", &pid, &comm);
+                pevent_register_comm(pevent, comm, pid);
+                free(comm);
+                line = strtok_r(NULL, "\n", &next);
+        }
+}
+
 int parse_ftrace_file(struct pevent *pevent, char *buf, unsigned long size)
 {
         return pevent_parse_event(pevent, buf, size, "ftrace");
diff --git a/tools/perf/util/trace-event-read.c b/tools/perf/util/trace-event-read.c
index b67a0ccf5ab9..27420159bf69 100644
--- a/tools/perf/util/trace-event-read.c
+++ b/tools/perf/util/trace-event-read.c
@@ -260,39 +260,53 @@ static int read_header_files(struct pevent *pevent)
 
 static int read_ftrace_file(struct pevent *pevent, unsigned long long size)
 {
+        int ret;
         char *buf;
 
         buf = malloc(size);
-        if (buf == NULL)
+        if (buf == NULL) {
+                pr_debug("memory allocation failure\n");
                 return -1;
+        }
 
-        if (do_read(buf, size) < 0) {
-                free(buf);
-                return -1;
+        ret = do_read(buf, size);
+        if (ret < 0) {
+                pr_debug("error reading ftrace file.\n");
+                goto out;
         }
 
-        parse_ftrace_file(pevent, buf, size);
+        ret = parse_ftrace_file(pevent, buf, size);
+        if (ret < 0)
+                pr_debug("error parsing ftrace file.\n");
+out:
         free(buf);
-        return 0;
+        return ret;
 }
 
 static int read_event_file(struct pevent *pevent, char *sys,
                             unsigned long long size)
 {
+        int ret;
         char *buf;
 
         buf = malloc(size);
-        if (buf == NULL)
+        if (buf == NULL) {
+                pr_debug("memory allocation failure\n");
                 return -1;
+        }
 
-        if (do_read(buf, size) < 0) {
+        ret = do_read(buf, size);
+        if (ret < 0) {
                 free(buf);
-                return -1;
+                goto out;
         }
 
-        parse_event_file(pevent, buf, size, sys);
+        ret = parse_event_file(pevent, buf, size, sys);
+        if (ret < 0)
+                pr_debug("error parsing event file.\n");
+out:
         free(buf);
-        return 0;
+        return ret;
 }
 
 static int read_ftrace_files(struct pevent *pevent)
@@ -341,6 +355,36 @@ static int read_event_files(struct pevent *pevent)
         return 0;
 }
 
+static int read_saved_cmdline(struct pevent *pevent)
+{
+        unsigned long long size;
+        char *buf;
+        int ret;
+
+        /* it can have 0 size */
+        size = read8(pevent);
+        if (!size)
+                return 0;
+
+        buf = malloc(size + 1);
+        if (buf == NULL) {
+                pr_debug("memory allocation failure\n");
+                return -1;
+        }
+
+        ret = do_read(buf, size);
+        if (ret < 0) {
+                pr_debug("error reading saved cmdlines\n");
+                goto out;
+        }
+
+        parse_saved_cmdline(pevent, buf, size);
+        ret = 0;
+out:
+        free(buf);
+        return ret;
+}
+
 ssize_t trace_report(int fd, struct trace_event *tevent, bool __repipe)
 {
         char buf[BUFSIZ];
@@ -379,10 +423,11 @@ ssize_t trace_report(int fd, struct trace_event *tevent, bool __repipe)
                 return -1;
         if (show_version)
                 printf("version = %s\n", version);
-        free(version);
 
-        if (do_read(buf, 1) < 0)
+        if (do_read(buf, 1) < 0) {
+                free(version);
                 return -1;
+        }
         file_bigendian = buf[0];
         host_bigendian = bigendian();
 
@@ -423,6 +468,11 @@ ssize_t trace_report(int fd, struct trace_event *tevent, bool __repipe)
         err = read_ftrace_printk(pevent);
         if (err)
                 goto out;
+        if (atof(version) >= 0.6) {
+                err = read_saved_cmdline(pevent);
+                if (err)
+                        goto out;
+        }
 
         size = trace_data_size;
         repipe = false;
@@ -438,5 +488,6 @@ ssize_t trace_report(int fd, struct trace_event *tevent, bool __repipe)
 out:
         if (pevent)
                 trace_event__cleanup(tevent);
+        free(version);
         return size;
 }
diff --git a/tools/perf/util/trace-event.h b/tools/perf/util/trace-event.h
index b0af9c81bb0d..1fbc044f9eb0 100644
--- a/tools/perf/util/trace-event.h
+++ b/tools/perf/util/trace-event.h
@@ -42,6 +42,7 @@ raw_field_value(struct event_format *event, const char *name, void *data);
 
 void parse_proc_kallsyms(struct pevent *pevent, char *file, unsigned int size);
 void parse_ftrace_printk(struct pevent *pevent, char *file, unsigned int size);
+void parse_saved_cmdline(struct pevent *pevent, char *file, unsigned int size);
 
 ssize_t trace_report(int fd, struct trace_event *tevent, bool repipe);
 
diff --git a/tools/perf/util/unwind-libunwind-local.c b/tools/perf/util/unwind-libunwind-local.c
index 6fec84dff3f7..bfb9b7987692 100644
--- a/tools/perf/util/unwind-libunwind-local.c
+++ b/tools/perf/util/unwind-libunwind-local.c
@@ -35,6 +35,7 @@
 #include "util.h"
 #include "debug.h"
 #include "asm/bug.h"
+#include "dso.h"
 
 extern int
 UNW_OBJ(dwarf_search_unwind_table) (unw_addr_space_t as,
@@ -297,15 +298,58 @@ static int read_unwind_spec_debug_frame(struct dso *dso,
         int fd;
         u64 ofs = dso->data.debug_frame_offset;
 
+        /* debug_frame can reside in:
+         *  - dso
+         *  - debug pointed by symsrc_filename
+         *  - gnu_debuglink, which doesn't necessary
+         *    has to be pointed by symsrc_filename
+         */
         if (ofs == 0) {
                 fd = dso__data_get_fd(dso, machine);
-                if (fd < 0)
-                        return -EINVAL;
+                if (fd >= 0) {
+                        ofs = elf_section_offset(fd, ".debug_frame");
+                        dso__data_put_fd(dso);
+                }
+
+                if (ofs <= 0) {
+                        fd = open(dso->symsrc_filename, O_RDONLY);
+                        if (fd >= 0) {
+                                ofs = elf_section_offset(fd, ".debug_frame");
+                                close(fd);
+                        }
+                }
+
+                if (ofs <= 0) {
+                        char *debuglink = malloc(PATH_MAX);
+                        int ret = 0;
+
+                        ret = dso__read_binary_type_filename(
+                                dso, DSO_BINARY_TYPE__DEBUGLINK,
+                                machine->root_dir, debuglink, PATH_MAX);
+                        if (!ret) {
+                                fd = open(debuglink, O_RDONLY);
+                                if (fd >= 0) {
+                                        ofs = elf_section_offset(fd,
+                                                        ".debug_frame");
+                                        close(fd);
+                                }
+                        }
+                        if (ofs > 0) {
+                                if (dso->symsrc_filename != NULL) {
+                                        pr_warning(
+                                                "%s: overwrite symsrc(%s,%s)\n",
+                                                        __func__,
+                                                        dso->symsrc_filename,
+                                                        debuglink);
+                                        free(dso->symsrc_filename);
+                                }
+                                dso->symsrc_filename = debuglink;
+                        } else {
+                                free(debuglink);
+                        }
+                }
 
-                /* Check the .debug_frame section for unwinding info */
-                ofs = elf_section_offset(fd, ".debug_frame");
                 dso->data.debug_frame_offset = ofs;
-                dso__data_put_fd(dso);
         }
 
         *offset = ofs;