tools/lib/traceevent/plugins/plugin_futex.c

   1 /*
   2  * Copyright (C) 2017 National Instruments Corp.
   3  *
   4  * Author: Julia Cartwright <julia@ni.com>
   5  *
   6  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   7  * This program is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation;
  10  * version 2.1 of the License (not later!)
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with this program; if not,  see <http://www.gnu.org/licenses>
  19  *
  20  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  21  */
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <string.h>
  25 #include <linux/futex.h>
  26
  27 #include "event-parse.h"
  28
  29 #define ARRAY_SIZE(_a) (sizeof(_a) / sizeof((_a)[0]))
  30
  31 struct futex_args {
  32         unsigned long long      uaddr;
  33         unsigned long long      op;
  34         unsigned long long      val;
  35         unsigned long long      utime; /* or val2 */
  36         unsigned long long      uaddr2;
  37         unsigned long long      val3;
  38 };
  39
  40 struct futex_op {
  41         const char      *name;
  42         const char      *fmt_val;
  43         const char      *fmt_utime;
  44         const char      *fmt_uaddr2;
  45         const char      *fmt_val3;
  46 };
  47
  48 static const struct futex_op futex_op_tbl[] = {
  49         {            "FUTEX_WAIT", " val=0x%08llx", " utime=0x%08llx",               NULL,             NULL },
  50         {            "FUTEX_WAKE",     " val=%llu",              NULL,               NULL,             NULL },
  51         {              "FUTEX_FD",     " val=%llu",              NULL,               NULL,             NULL },
  52         {         "FUTEX_REQUEUE",     " val=%llu",      " val2=%llu", " uaddr2=0x%08llx",             NULL },
  53         {     "FUTEX_CMP_REQUEUE",     " val=%llu",      " val2=%llu", " uaddr2=0x%08llx", " val3=0x%08llx" },
  54         {         "FUTEX_WAKE_OP",     " val=%llu",      " val2=%llu", " uaddr2=0x%08llx", " val3=0x%08llx" },
  55         {         "FUTEX_LOCK_PI",            NULL, " utime=0x%08llx",               NULL,             NULL },
  56         {       "FUTEX_UNLOCK_PI",            NULL,              NULL,               NULL,             NULL },
  57         {      "FUTEX_TRYLOCK_PI",            NULL,              NULL,               NULL,             NULL },
  58         {     "FUTEX_WAIT_BITSET", " val=0x%08llx", " utime=0x%08llx",               NULL, " val3=0x%08llx" },
  59         {     "FUTEX_WAKE_BITSET",     " val=%llu",              NULL,               NULL, " val3=0x%08llx" },
  60         { "FUTEX_WAIT_REQUEUE_PI", " val=0x%08llx", " utime=0x%08llx", " uaddr2=0x%08llx", " val3=0x%08llx" },
  61         {  "FUTEX_CMP_REQUEUE_PI",     " val=%llu",      " val2=%llu", " uaddr2=0x%08llx", " val3=0x%08llx" },
  62 };
  63
  64
  65 static void futex_print(struct trace_seq *s, const struct futex_args *args,
  66                         const struct futex_op *fop)
  67 {
  68         trace_seq_printf(s, " uaddr=0x%08llx", args->uaddr);
  69
  70         if (fop->fmt_val)
  71                 trace_seq_printf(s, fop->fmt_val, args->val);
  72
  73         if (fop->fmt_utime)
  74                 trace_seq_printf(s,fop->fmt_utime, args->utime);
  75
  76         if (fop->fmt_uaddr2)
  77                 trace_seq_printf(s, fop->fmt_uaddr2, args->uaddr2);
  78
  79         if (fop->fmt_val3)
  80                 trace_seq_printf(s, fop->fmt_val3, args->val3);
  81 }
  82
  83 static int futex_handler(struct trace_seq *s, struct tep_record *record,
  84                          struct tep_event *event, void *context)
  85 {
  86         const struct futex_op *fop;
  87         struct futex_args args;
  88         unsigned long long cmd;
  89
  90         if (tep_get_field_val(s, event, "uaddr", record, &args.uaddr, 1))
  91                 return 1;
  92
  93         if (tep_get_field_val(s, event, "op", record, &args.op, 1))
  94                 return 1;
  95
  96         if (tep_get_field_val(s, event, "val", record, &args.val, 1))
  97                 return 1;
  98
  99         if (tep_get_field_val(s, event, "utime", record, &args.utime, 1))
 100                 return 1;
 101
 102         if (tep_get_field_val(s, event, "uaddr2", record, &args.uaddr2, 1))
 103                 return 1;
 104
 105         if (tep_get_field_val(s, event, "val3", record, &args.val3, 1))
 106                 return 1;
 107
 108         cmd = args.op & FUTEX_CMD_MASK;
 109         if (cmd >= ARRAY_SIZE(futex_op_tbl))
 110                 return 1;
 111
 112         fop = &futex_op_tbl[cmd];
 113
 114         trace_seq_printf(s, "op=%s", fop->name);
 115
 116         if (args.op & FUTEX_PRIVATE_FLAG)
 117                 trace_seq_puts(s, "|FUTEX_PRIVATE_FLAG");
 118
 119         if (args.op & FUTEX_CLOCK_REALTIME)
 120                 trace_seq_puts(s, "|FUTEX_CLOCK_REALTIME");
 121
 122         futex_print(s, &args, fop);
 123         return 0;
 124 }
 125
 126 int TEP_PLUGIN_LOADER(struct tep_handle *tep)
 127 {
 128         tep_register_event_handler(tep, -1, "syscalls", "sys_enter_futex",
 129                                    futex_handler, NULL);
 130         return 0;
 131 }
 132
 133 void TEP_PLUGIN_UNLOADER(struct tep_handle *tep)
 134 {
 135         tep_unregister_event_handler(tep, -1, "syscalls", "sys_enter_futex",
 136                                      futex_handler, NULL);
 137 }