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

Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:

User visible changes:

  - Allow callchain order (caller, callee) to the libdw and libunwind based DWARF
    unwinders (Jiri Olsa)

  - Add missing parent_val initialization in the callchain code, fixing a
    SEGFAULT when using callchains with 'perf top' (Jiri Olsa)

  - Add initial 'perf config' command, for now just with a --list command to the
    contents of the configuration file in use and a basic man page describing
    its format, commands for doing edits and detailed documentation are being
    reviewed and proof-read. (Taeung Song)

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

11 files changed, 272 insertions, 39 deletions

diff --git a/tools/perf/Build b/tools/perf/Build
index 72237455b400..2c7aaf2ba119 100644
--- a/tools/perf/Build
+++ b/tools/perf/Build
@@ -1,5 +1,6 @@
 perf-y += builtin-bench.o
 perf-y += builtin-annotate.o
+perf-y += builtin-config.o
 perf-y += builtin-diff.o
 perf-y += builtin-evlist.o
 perf-y += builtin-help.o
diff --git a/tools/perf/Documentation/perf-config.txt b/tools/perf/Documentation/perf-config.txt
new file mode 100644
index 000000000000..b9ca1e304158
--- /dev/null
+++ b/tools/perf/Documentation/perf-config.txt
@@ -0,0 +1,103 @@
+perf-config(1)
+==============
+
+NAME
+----
+perf-config - Get and set variables in a configuration file.
+
+SYNOPSIS
+--------
+[verse]
+'perf config' -l | --list
+
+DESCRIPTION
+-----------
+You can manage variables in a configuration file with this command.
+
+OPTIONS
+-------
+
+-l::
+--list::
+        Show current config variables, name and value, for all sections.
+
+CONFIGURATION FILE
+------------------
+
+The perf configuration file contains many variables to change various
+aspects of each of its tools, including output, disk usage, etc.
+The '$HOME/.perfconfig' file is used to store a per-user configuration.
+The file '$(sysconfdir)/perfconfig' can be used to
+store a system-wide default configuration.
+
+Syntax
+~~~~~~
+
+The file consist of sections. A section starts with its name
+surrounded by square brackets and continues till the next section
+begins. Each variable must be in a section, and have the form
+'name = value', for example:
+
+        [section]
+                name1 = value1
+                name2 = value2
+
+Section names are case sensitive and can contain any characters except
+newline (double quote `"` and backslash have to be escaped as `\"` and `\\`,
+respectively). Section headers can't span multiple lines.
+
+Example
+~~~~~~~
+
+Given a $HOME/.perfconfig like this:
+
+#
+# This is the config file, and
+# a '#' and ';' character indicates a comment
+#
+
+        [colors]
+                # Color variables
+                top = red, default
+                medium = green, default
+                normal = lightgray, default
+                selected = white, lightgray
+                code = blue, default
+                addr = magenta, default
+                root = white, blue
+
+        [tui]
+                # Defaults if linked with libslang
+                report = on
+                annotate = on
+                top = on
+
+        [buildid]
+                # Default, disable using /dev/null
+                dir = ~/.debug
+
+        [annotate]
+                # Defaults
+                hide_src_code = false
+                use_offset = true
+                jump_arrows = true
+                show_nr_jumps = false
+
+        [help]
+                # Format can be man, info, web or html
+                format = man
+                autocorrect = 0
+
+        [ui]
+                show-headers = true
+
+        [call-graph]
+                # fp (framepointer), dwarf
+                record-mode = fp
+                print-type = graph
+                order = caller
+                sort-key = function
+
+SEE ALSO
+--------
+linkperf:perf[1]
diff --git a/tools/perf/builtin-config.c b/tools/perf/builtin-config.c
new file mode 100644
index 000000000000..427ea7a705b8
--- /dev/null
+++ b/tools/perf/builtin-config.c
@@ -0,0 +1,66 @@
+/*
+ * builtin-config.c
+ *
+ * Copyright (C) 2015, Taeung Song <treeze.taeung@gmail.com>
+ *
+ */
+#include "builtin.h"
+
+#include "perf.h"
+
+#include "util/cache.h"
+#include "util/parse-options.h"
+#include "util/util.h"
+#include "util/debug.h"
+
+static const char * const config_usage[] = {
+        "perf config [options]",
+        NULL
+};
+
+enum actions {
+        ACTION_LIST = 1
+} actions;
+
+static struct option config_options[] = {
+        OPT_SET_UINT('l', "list", &actions,
+                     "show current config variables", ACTION_LIST),
+        OPT_END()
+};
+
+static int show_config(const char *key, const char *value,
+                       void *cb __maybe_unused)
+{
+        if (value)
+                printf("%s=%s\n", key, value);
+        else
+                printf("%s\n", key);
+
+        return 0;
+}
+
+int cmd_config(int argc, const char **argv, const char *prefix __maybe_unused)
+{
+        int ret = 0;
+
+        argc = parse_options(argc, argv, config_options, config_usage,
+                             PARSE_OPT_STOP_AT_NON_OPTION);
+
+        switch (actions) {
+        case ACTION_LIST:
+                if (argc) {
+                        pr_err("Error: takes no arguments\n");
+                        parse_options_usage(config_usage, config_options, "l", 1);
+                } else {
+                        ret = perf_config(show_config, NULL);
+                        if (ret < 0)
+                                pr_err("Nothing configured, "
+                                       "please check your ~/.perfconfig file\n");
+                }
+                break;
+        default:
+                usage_with_options(config_usage, config_options);
+        }
+
+        return ret;
+}
diff --git a/tools/perf/builtin.h b/tools/perf/builtin.h
index 3688ad29085f..3f871b54e261 100644
--- a/tools/perf/builtin.h
+++ b/tools/perf/builtin.h
@@ -17,6 +17,7 @@ extern int cmd_annotate(int argc, const char **argv, const char *prefix);
 extern int cmd_bench(int argc, const char **argv, const char *prefix);
 extern int cmd_buildid_cache(int argc, const char **argv, const char *prefix);
 extern int cmd_buildid_list(int argc, const char **argv, const char *prefix);
+extern int cmd_config(int argc, const char **argv, const char *prefix);
 extern int cmd_diff(int argc, const char **argv, const char *prefix);
 extern int cmd_evlist(int argc, const char **argv, const char *prefix);
 extern int cmd_help(int argc, const char **argv, const char *prefix);
diff --git a/tools/perf/command-list.txt b/tools/perf/command-list.txt
index 00fcaf8a5b8d..acc3ea7d90b7 100644
--- a/tools/perf/command-list.txt
+++ b/tools/perf/command-list.txt
@@ -9,6 +9,7 @@ perf-buildid-cache		mainporcelain common
 perf-buildid-list               mainporcelain common
 perf-data                       mainporcelain common
 perf-diff                       mainporcelain common
+perf-config                     mainporcelain common
 perf-evlist                     mainporcelain common
 perf-inject                     mainporcelain common
 perf-kmem                       mainporcelain common
diff --git a/tools/perf/perf.c b/tools/perf/perf.c
index 3d4c7c09adea..4bee53c3f796 100644
--- a/tools/perf/perf.c
+++ b/tools/perf/perf.c
@@ -39,6 +39,7 @@ struct cmd_struct {
 static struct cmd_struct commands[] = {
         { "buildid-cache", cmd_buildid_cache, 0 },
         { "buildid-list", cmd_buildid_list, 0 },
+        { "config",     cmd_config,     0 },
         { "diff",       cmd_diff,       0 },
         { "evlist",     cmd_evlist,     0 },
         { "help",       cmd_help,       0 },
diff --git a/tools/perf/tests/dwarf-unwind.c b/tools/perf/tests/dwarf-unwind.c
index 01f0b61de53d..b2357e8115a2 100644
--- a/tools/perf/tests/dwarf-unwind.c
+++ b/tools/perf/tests/dwarf-unwind.c
@@ -51,6 +51,12 @@ static int unwind_entry(struct unwind_entry *entry, void *arg)
                 "krava_1",
                 "test__dwarf_unwind"
         };
+        /*
+         * The funcs[MAX_STACK] array index, based on the
+         * callchain order setup.
+         */
+        int idx = callchain_param.order == ORDER_CALLER ?
+                  MAX_STACK - *cnt - 1 : *cnt;
 
         if (*cnt >= MAX_STACK) {
                 pr_debug("failed: crossed the max stack value %d\n", MAX_STACK);
@@ -63,8 +69,10 @@ static int unwind_entry(struct unwind_entry *entry, void *arg)
                 return -1;
         }
 
-        pr_debug("got: %s 0x%" PRIx64 "\n", symbol, entry->ip);
-        return strcmp((const char *) symbol, funcs[(*cnt)++]);
+        (*cnt)++;
+        pr_debug("got: %s 0x%" PRIx64 ", expecting %s\n",
+                 symbol, entry->ip, funcs[idx]);
+        return strcmp((const char *) symbol, funcs[idx]);
 }
 
 __attribute__ ((noinline))
@@ -105,8 +113,16 @@ static int compare(void *p1, void *p2)
         /* Any possible value should be 'thread' */
         struct thread *thread = *(struct thread **)p1;
 
-        if (global_unwind_retval == -INT_MAX)
+        if (global_unwind_retval == -INT_MAX) {
+                /* Call unwinder twice for both callchain orders. */
+                callchain_param.order = ORDER_CALLER;
+
                 global_unwind_retval = unwind_thread(thread);
+                if (!global_unwind_retval) {
+                        callchain_param.order = ORDER_CALLEE;
+                        global_unwind_retval = unwind_thread(thread);
+                }
+        }
 
         return p1 - p2;
 }
diff --git a/tools/perf/util/callchain.h b/tools/perf/util/callchain.h
index 6e9b5f2099e1..8ac8f043004c 100644
--- a/tools/perf/util/callchain.h
+++ b/tools/perf/util/callchain.h
@@ -143,6 +143,7 @@ extern __thread struct callchain_cursor callchain_cursor;
 static inline void callchain_init(struct callchain_root *root)
 {
         INIT_LIST_HEAD(&root->node.val);
+        INIT_LIST_HEAD(&root->node.parent_val);
 
         root->node.parent = NULL;
         root->node.hit = 0;
diff --git a/tools/perf/util/unwind-libdw.c b/tools/perf/util/unwind-libdw.c
index 2dcfe9a7c8d0..db8142ba7cb9 100644
--- a/tools/perf/util/unwind-libdw.c
+++ b/tools/perf/util/unwind-libdw.c
@@ -11,6 +11,7 @@
 #include <linux/types.h>
 #include "event.h"
 #include "perf_regs.h"
+#include "callchain.h"
 
 static char *debuginfo_path;
 
@@ -52,25 +53,28 @@ static int report_module(u64 ip, struct unwind_info *ui)
         return __report_module(&al, ip, ui);
 }
 
+/*
+ * Store all entries within entries array,
+ * we will process it after we finish unwind.
+ */
 static int entry(u64 ip, struct unwind_info *ui)
 
 {
-        struct unwind_entry e;
+        struct unwind_entry *e = &ui->entries[ui->idx++];
         struct addr_location al;
 
         if (__report_module(&al, ip, ui))
                 return -1;
 
-        e.ip  = ip;
-        e.map = al.map;
-        e.sym = al.sym;
+        e->ip  = ip;
+        e->map = al.map;
+        e->sym = al.sym;
 
         pr_debug("unwind: %s:ip = 0x%" PRIx64 " (0x%" PRIx64 ")\n",
                  al.sym ? al.sym->name : "''",
                  ip,
                  al.map ? al.map->map_ip(al.map, ip) : (u64) 0);
-
-        return ui->cb(&e, ui->arg);
+        return 0;
 }
 
 static pid_t next_thread(Dwfl *dwfl, void *arg, void **thread_argp)
@@ -168,7 +172,7 @@ int unwind__get_entries(unwind_entry_cb_t cb, void *arg,
                         struct perf_sample *data,
                         int max_stack)
 {
-        struct unwind_info ui = {
+        struct unwind_info *ui, ui_buf = {
                 .sample         = data,
                 .thread         = thread,
                 .machine        = thread->mg->machine,
@@ -177,35 +181,54 @@ int unwind__get_entries(unwind_entry_cb_t cb, void *arg,
                 .max_stack      = max_stack,
         };
         Dwarf_Word ip;
-        int err = -EINVAL;
+        int err = -EINVAL, i;
 
         if (!data->user_regs.regs)
                 return -EINVAL;
 
-        ui.dwfl = dwfl_begin(&offline_callbacks);
-        if (!ui.dwfl)
+        ui = zalloc(sizeof(ui_buf) + sizeof(ui_buf.entries[0]) * max_stack);
+        if (!ui)
+                return -ENOMEM;
+
+        *ui = ui_buf;
+
+        ui->dwfl = dwfl_begin(&offline_callbacks);
+        if (!ui->dwfl)
                 goto out;
 
         err = perf_reg_value(&ip, &data->user_regs, PERF_REG_IP);
         if (err)
                 goto out;
 
-        err = report_module(ip, &ui);
+        err = report_module(ip, ui);
         if (err)
                 goto out;
 
-        if (!dwfl_attach_state(ui.dwfl, EM_NONE, thread->tid, &callbacks, &ui))
+        if (!dwfl_attach_state(ui->dwfl, EM_NONE, thread->tid, &callbacks, ui))
                 goto out;
 
-        err = dwfl_getthread_frames(ui.dwfl, thread->tid, frame_callback, &ui);
+        err = dwfl_getthread_frames(ui->dwfl, thread->tid, frame_callback, ui);
 
-        if (err && !ui.max_stack)
+        if (err && !ui->max_stack)
                 err = 0;
 
+        /*
+         * Display what we got based on the order setup.
+         */
+        for (i = 0; i < ui->idx && !err; i++) {
+                int j = i;
+
+                if (callchain_param.order == ORDER_CALLER)
+                        j = ui->idx - i - 1;
+
+                err = ui->entries[j].ip ? ui->cb(&ui->entries[j], ui->arg) : 0;
+        }
+
  out:
         if (err)
                 pr_debug("unwind: failed with '%s'\n", dwfl_errmsg(-1));
 
-        dwfl_end(ui.dwfl);
+        dwfl_end(ui->dwfl);
+        free(ui);
         return 0;
 }
diff --git a/tools/perf/util/unwind-libdw.h b/tools/perf/util/unwind-libdw.h
index 417a1426f3ad..58328669ed16 100644
--- a/tools/perf/util/unwind-libdw.h
+++ b/tools/perf/util/unwind-libdw.h
@@ -16,6 +16,8 @@ struct unwind_info {
         unwind_entry_cb_t       cb;
         void                    *arg;
         int                     max_stack;
+        int                     idx;
+        struct unwind_entry     entries[];
 };
 
 #endif /* __PERF_UNWIND_LIBDW_H */
diff --git a/tools/perf/util/unwind-libunwind.c b/tools/perf/util/unwind-libunwind.c
index c83832b555e5..3c258a0e4092 100644
--- a/tools/perf/util/unwind-libunwind.c
+++ b/tools/perf/util/unwind-libunwind.c
@@ -614,23 +614,48 @@ void unwind__finish_access(struct thread *thread)
 static int get_entries(struct unwind_info *ui, unwind_entry_cb_t cb,
                        void *arg, int max_stack)
 {
+        u64 val;
+        unw_word_t ips[max_stack];
         unw_addr_space_t addr_space;
         unw_cursor_t c;
-        int ret;
-
-        addr_space = thread__priv(ui->thread);
-        if (addr_space == NULL)
-                return -1;
+        int ret, i = 0;
 
-        ret = unw_init_remote(&c, addr_space, ui);
+        ret = perf_reg_value(&val, &ui->sample->user_regs, PERF_REG_IP);
         if (ret)
-                display_error(ret);
+                return ret;
 
-        while (!ret && (unw_step(&c) > 0) && max_stack--) {
-                unw_word_t ip;
+        ips[i++] = (unw_word_t) val;
 
-                unw_get_reg(&c, UNW_REG_IP, &ip);
-                ret = ip ? entry(ip, ui->thread, cb, arg) : 0;
+        /*
+         * If we need more than one entry, do the DWARF
+         * unwind itself.
+         */
+        if (max_stack - 1 > 0) {
+                addr_space = thread__priv(ui->thread);
+                if (addr_space == NULL)
+                        return -1;
+
+                ret = unw_init_remote(&c, addr_space, ui);
+                if (ret)
+                        display_error(ret);
+
+                while (!ret && (unw_step(&c) > 0) && i < max_stack) {
+                        unw_get_reg(&c, UNW_REG_IP, &ips[i]);
+                        ++i;
+                }
+
+                max_stack = i;
+        }
+
+        /*
+         * Display what we got based on the order setup.
+         */
+        for (i = 0; i < max_stack && !ret; i++) {
+                int j = i;
+
+                if (callchain_param.order == ORDER_CALLER)
+                        j = max_stack - i - 1;
+                ret = ips[j] ? entry(ips[j], ui->thread, cb, arg) : 0;
         }
 
         return ret;
@@ -640,24 +665,17 @@ int unwind__get_entries(unwind_entry_cb_t cb, void *arg,
                         struct thread *thread,
                         struct perf_sample *data, int max_stack)
 {
-        u64 ip;
         struct unwind_info ui = {
                 .sample       = data,
                 .thread       = thread,
                 .machine      = thread->mg->machine,
         };
-        int ret;
 
         if (!data->user_regs.regs)
                 return -EINVAL;
 
-        ret = perf_reg_value(&ip, &data->user_regs, PERF_REG_IP);
-        if (ret)
-                return ret;
-
-        ret = entry(ip, thread, cb, arg);
-        if (ret)
-                return -ENOMEM;
+        if (max_stack <= 0)
+                return -EINVAL;
 
-        return --max_stack > 0 ? get_entries(&ui, cb, arg, max_stack) : 0;
+        return get_entries(&ui, cb, arg, max_stack);
 }