1// SPDX-License-Identifier: LGPL-2.1
  2/*
  3 * Copyright (C) 2017 National Instruments Corp.
  4 *
  5 * Author: Julia Cartwright <julia@ni.com>
  6 *
  7 */
  8#include <stdio.h>
  9#include <stdlib.h>
 10#include <string.h>
 11#include <linux/futex.h>
 12
 13#include "event-parse.h"
 14
 15#define ARRAY_SIZE(_a) (sizeof(_a) / sizeof((_a)[0]))
 16
 17struct futex_args {
 18	unsigned long long	uaddr;
 19	unsigned long long	op;
 20	unsigned long long	val;
 21	unsigned long long	utime; /* or val2 */
 22	unsigned long long	uaddr2;
 23	unsigned long long	val3;
 24};
 25
 26struct futex_op {
 27	const char	*name;
 28	const char	*fmt_val;
 29	const char	*fmt_utime;
 30	const char	*fmt_uaddr2;
 31	const char	*fmt_val3;
 32};
 33
 34static const struct futex_op futex_op_tbl[] = {
 35	{            "FUTEX_WAIT", " val=0x%08llx", " utime=0x%08llx",               NULL,             NULL },
 36	{            "FUTEX_WAKE",     " val=%llu",              NULL,               NULL,             NULL },
 37	{              "FUTEX_FD",     " val=%llu",              NULL,               NULL,             NULL },
 38	{         "FUTEX_REQUEUE",     " val=%llu",      " val2=%llu", " uaddr2=0x%08llx",             NULL },
 39	{     "FUTEX_CMP_REQUEUE",     " val=%llu",      " val2=%llu", " uaddr2=0x%08llx", " val3=0x%08llx" },
 40	{         "FUTEX_WAKE_OP",     " val=%llu",      " val2=%llu", " uaddr2=0x%08llx", " val3=0x%08llx" },
 41	{         "FUTEX_LOCK_PI",            NULL, " utime=0x%08llx",               NULL,             NULL },
 42	{       "FUTEX_UNLOCK_PI",            NULL,              NULL,               NULL,             NULL },
 43	{      "FUTEX_TRYLOCK_PI",            NULL,              NULL,               NULL,             NULL },
 44	{     "FUTEX_WAIT_BITSET", " val=0x%08llx", " utime=0x%08llx",               NULL, " val3=0x%08llx" },
 45	{     "FUTEX_WAKE_BITSET",     " val=%llu",              NULL,               NULL, " val3=0x%08llx" },
 46	{ "FUTEX_WAIT_REQUEUE_PI", " val=0x%08llx", " utime=0x%08llx", " uaddr2=0x%08llx", " val3=0x%08llx" },
 47	{  "FUTEX_CMP_REQUEUE_PI",     " val=%llu",      " val2=%llu", " uaddr2=0x%08llx", " val3=0x%08llx" },
 48};
 49
 50
 51static void futex_print(struct trace_seq *s, const struct futex_args *args,
 52			const struct futex_op *fop)
 53{
 54	trace_seq_printf(s, " uaddr=0x%08llx", args->uaddr);
 55
 56	if (fop->fmt_val)
 57		trace_seq_printf(s, fop->fmt_val, args->val);
 58
 59	if (fop->fmt_utime)
 60		trace_seq_printf(s,fop->fmt_utime, args->utime);
 61
 62	if (fop->fmt_uaddr2)
 63		trace_seq_printf(s, fop->fmt_uaddr2, args->uaddr2);
 64
 65	if (fop->fmt_val3)
 66		trace_seq_printf(s, fop->fmt_val3, args->val3);
 67}
 68
 69static int futex_handler(struct trace_seq *s, struct tep_record *record,
 70			 struct tep_event *event, void *context)
 71{
 72	const struct futex_op *fop;
 73	struct futex_args args;
 74	unsigned long long cmd;
 75
 76	if (tep_get_field_val(s, event, "uaddr", record, &args.uaddr, 1))
 77		return 1;
 78
 79	if (tep_get_field_val(s, event, "op", record, &args.op, 1))
 80		return 1;
 81
 82	if (tep_get_field_val(s, event, "val", record, &args.val, 1))
 83		return 1;
 84
 85	if (tep_get_field_val(s, event, "utime", record, &args.utime, 1))
 86		return 1;
 87
 88	if (tep_get_field_val(s, event, "uaddr2", record, &args.uaddr2, 1))
 89		return 1;
 90
 91	if (tep_get_field_val(s, event, "val3", record, &args.val3, 1))
 92		return 1;
 93
 94	cmd = args.op & FUTEX_CMD_MASK;
 95	if (cmd >= ARRAY_SIZE(futex_op_tbl))
 96		return 1;
 97
 98	fop = &futex_op_tbl[cmd];
 99
100	trace_seq_printf(s, "op=%s", fop->name);
101
102	if (args.op & FUTEX_PRIVATE_FLAG)
103		trace_seq_puts(s, "|FUTEX_PRIVATE_FLAG");
104
105	if (args.op & FUTEX_CLOCK_REALTIME)
106		trace_seq_puts(s, "|FUTEX_CLOCK_REALTIME");
107
108	futex_print(s, &args, fop);
109	return 0;
110}
111
112int TEP_PLUGIN_LOADER(struct tep_handle *tep)
113{
114	tep_register_event_handler(tep, -1, "syscalls", "sys_enter_futex",
115				   futex_handler, NULL);
116	return 0;
117}
118
119void TEP_PLUGIN_UNLOADER(struct tep_handle *tep)
120{
121	tep_unregister_event_handler(tep, -1, "syscalls", "sys_enter_futex",
122				     futex_handler, NULL);
123}