1 
2 /*--------------------------------------------------------------------*/
3 /*--- The thread state.                            m_threadstate.c ---*/
4 /*--------------------------------------------------------------------*/
5 
6 /*
7    This file is part of Valgrind, a dynamic binary instrumentation
8    framework.
9 
10    Copyright (C) 2000-2015 Julian Seward
11       jseward@acm.org
12 
13    This program is free software; you can redistribute it and/or
14    modify it under the terms of the GNU General Public License as
15    published by the Free Software Foundation; either version 2 of the
16    License, or (at your option) any later version.
17 
18    This program is distributed in the hope that it will be useful, but
19    WITHOUT ANY WARRANTY; without even the implied warranty of
20    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
21    General Public License for more details.
22 
23    You should have received a copy of the GNU General Public License
24    along with this program; if not, write to the Free Software
25    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
26    02111-1307, USA.
27 
28    The GNU General Public License is contained in the file COPYING.
29 */
30 
31 #include "pub_core_basics.h"
32 #include "pub_core_vki.h"
33 #include "pub_core_threadstate.h"
34 #include "pub_core_mallocfree.h"    // VG_(malloc)
35 #include "pub_core_libcassert.h"
36 #include "pub_core_inner.h"
37 #if defined(ENABLE_INNER_CLIENT_REQUEST)
38 #include "helgrind/helgrind.h"
39 #endif
40 
41 /*------------------------------------------------------------*/
42 /*--- Data structures.                                     ---*/
43 /*------------------------------------------------------------*/
44 
45 ThreadId VG_(running_tid) = VG_INVALID_THREADID;
46 
47 ThreadState *VG_(threads);
48 UInt VG_N_THREADS;
49 
50 /*------------------------------------------------------------*/
51 /*--- Operations.                                          ---*/
52 /*------------------------------------------------------------*/
53 
VG_(init_Threads)54 void VG_(init_Threads)(void)
55 {
56    ThreadId tid;
57 
58    VG_(threads) = VG_(arena_memalign) (VG_AR_CORE, "init_Threads",
59                                        LibVEX_GUEST_STATE_ALIGN,
60                                        VG_N_THREADS * sizeof VG_(threads)[0]);
61 
62    for (tid = 1; tid < VG_N_THREADS; tid++) {
63       INNER_REQUEST(
64          ANNOTATE_BENIGN_RACE_SIZED(&VG_(threads)[tid].status,
65                                     sizeof(VG_(threads)[tid].status), ""));
66       INNER_REQUEST(
67          ANNOTATE_BENIGN_RACE_SIZED(&VG_(threads)[tid].os_state.exitcode,
68                                     sizeof(VG_(threads)[tid].os_state.exitcode),
69                                     ""));
70    }
71 }
72 
VG_(name_of_ThreadStatus)73 const HChar* VG_(name_of_ThreadStatus) ( ThreadStatus status )
74 {
75    switch (status) {
76    case VgTs_Empty:     return "VgTs_Empty";
77    case VgTs_Init:      return "VgTs_Init";
78    case VgTs_Runnable:  return "VgTs_Runnable";
79    case VgTs_WaitSys:   return "VgTs_WaitSys";
80    case VgTs_Yielding:  return "VgTs_Yielding";
81    case VgTs_Zombie:    return "VgTs_Zombie";
82    default:             return "VgTs_???";
83   }
84 }
85 
VG_(name_of_VgSchedReturnCode)86 const HChar* VG_(name_of_VgSchedReturnCode) ( VgSchedReturnCode retcode )
87 {
88    switch (retcode) {
89    case VgSrc_None:        return "VgSrc_None";
90    case VgSrc_ExitThread:  return "VgSrc_ExitThread";
91    case VgSrc_ExitProcess: return "VgSrc_ExitProcess";
92    case VgSrc_FatalSig:    return "VgSrc_FatalSig";
93    default:                return "VgSrc_???";
94   }
95 }
96 
VG_(get_ThreadState)97 ThreadState *VG_(get_ThreadState)(ThreadId tid)
98 {
99    vg_assert(tid >= 0 && tid < VG_N_THREADS);
100    vg_assert(VG_(threads)[tid].tid == tid);
101    return &VG_(threads)[tid];
102 }
103 
VG_(is_valid_tid)104 Bool VG_(is_valid_tid) ( ThreadId tid )
105 {
106    /* tid is unsigned, hence no < 0 test. */
107    if (tid == 0) return False;
108    if (tid >= VG_N_THREADS) return False;
109    if (VG_(threads)[tid].status == VgTs_Empty) return False;
110    return True;
111 }
112 
113 // This function is for tools to call.
VG_(get_running_tid)114 ThreadId VG_(get_running_tid)(void)
115 {
116    return VG_(running_tid);
117 }
118 
VG_(is_running_thread)119 Bool VG_(is_running_thread)(ThreadId tid)
120 {
121    ThreadState *tst = VG_(get_ThreadState)(tid);
122 
123    return
124 //      tst->os_state.lwpid == VG_(gettid)() &&	// check we're this tid
125       VG_(running_tid) == tid	           &&	// and that we've got the lock
126       tst->status == VgTs_Runnable;		// and we're runnable
127 }
128 
129 /* Return true if the thread is still alive but in the process of exiting. */
VG_(is_exiting)130 inline Bool VG_(is_exiting)(ThreadId tid)
131 {
132    vg_assert(VG_(is_valid_tid)(tid));
133    return VG_(threads)[tid].exitreason != VgSrc_None;
134 }
135 
136 /* Return the number of non-dead Threads */
VG_(count_living_threads)137 Int VG_(count_living_threads)(void)
138 {
139    Int count = 0;
140    ThreadId tid;
141 
142    for(tid = 1; tid < VG_N_THREADS; tid++)
143       if (VG_(threads)[tid].status != VgTs_Empty &&
144 	  VG_(threads)[tid].status != VgTs_Zombie)
145 	 count++;
146 
147    return count;
148 }
149 
150 /* Return the number of threads in VgTs_Runnable state */
VG_(count_runnable_threads)151 Int VG_(count_runnable_threads)(void)
152 {
153    Int count = 0;
154    ThreadId tid;
155 
156    for(tid = 1; tid < VG_N_THREADS; tid++)
157       if (VG_(threads)[tid].status == VgTs_Runnable)
158 	 count++;
159 
160    return count;
161 }
162 
163 /* Given an LWP id (ie, real kernel thread id), find the corresponding
164    ThreadId */
VG_(lwpid_to_vgtid)165 ThreadId VG_(lwpid_to_vgtid)(Int lwp)
166 {
167    ThreadId tid;
168 
169    for(tid = 1; tid < VG_N_THREADS; tid++)
170       if (VG_(threads)[tid].status != VgTs_Empty
171           && VG_(threads)[tid].os_state.lwpid == lwp)
172 	 return tid;
173 
174    return VG_INVALID_THREADID;
175 }
176 
177 /*--------------------------------------------------------------------*/
178 /*--- end                                                          ---*/
179 /*--------------------------------------------------------------------*/
180