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<div class="Head1">
<h2>Current Thread State</h2>
</div>
<div>
<p>The current thread is the thread that was executing when the fault
occurred. The 23 lines starting at line 10 of the output gives information
relating to the current thread:</p>
<p class="listing">TheCurrentThread=64039408<br>
THREAD at 64039408 VPTR=f803423c AccessCount=3 Owner=64038d5c<br>Full name test2.exe::Main<br>Thread MState READY<br>Default priority 16 WaitLink Priority 16<br>ExitInfo 2,100,USER<br>Flags 00000004, Handles 640330bc<br>Supervisor stack base 6571f000 size 1000<br>User stack base 00402000 size 2000<br>Id=26, Alctr=00600000, Created alctr=00600000, Frame=00000000<br>Trap handler=00000000, ActiveScheduler=00000000, Exception handler=00000000<br>TempObj=00000000 TempAlloc=00000000 IpcCount=00000000<br>NThread @ 640396b0 Pri 16 NState READY<br>Next=640396b0 Prev=640396b0 Att=03 iUserContextType=0b<br>HeldFM=00000000 WaitFM=00000000 AddrSp=64038d5c<br>Time=17 Timeslice=20 ReqCount=0<br>SuspendCount=0 CsCount=1 CsFunction=fffffffe<br>SavedSP=6571ff34 ExtraContext=00000000 ExtraContextSize=0000<br>DACR 63990000<br>R13_USR 6571ff88 R14_USR f8025bc0 SPSR_SVC 10000004<br>
R4 f8033794 R5 64039408 R6 640396b0 R7 f8028518<br>
R8 640396b0 R9 640396b0 R10 00000000 R11 f80284d8<br>
PC 00000000</p>
<ul>
<li>
<p><b><a href="CrashDebuggerInfoAboutKernel.guide03.html" title="Extracting information about the kernel / Current thread state / Thread object and access count">Thread object and access count</a></b></p>
</li>
<li class="style14">
<p><a href="CrashDebuggerInfoAboutKernel.guide03.html#debugging%2einfo%2dabout%2dkernel%2ethread%2dstate%2ename" title="Extracting information about the kernel / Current thread state / The thread name">The thread name</a></p>
</li>
<li class="style14">
<p><a href="CrashDebuggerInfoAboutKernel.guide03.html#debugging%2einfo%2dabout%2dkernel%2ethread%2dstate%2estate" title="Extracting information about the kernel / Current thread state / The thread state, exit information, priority">The thread state, exit information, priority</a></p>
</li>
<li class="style14">
<p><a href="CrashDebuggerInfoAboutKernel.guide03.html#debugging%2einfo%2dabout%2dkernel%2ethread%2dstate%2eflags" title="Extracting information about the kernel / Current thread state / Thread flags">Thread flags</a></p>
</li>
<li class="style14">
<p><a href="CrashDebuggerInfoAboutKernel.guide03.html#debugging%2einfo%2dabout%2dkernel%2ethread%2dstate%2ehandles" title="Extracting information about the kernel / Current thread state / Handles">Handles</a></p>
</li>
<li class="style14">
<p><a href="CrashDebuggerInfoAboutKernel.guide03.html#debugging%2einfo%2dabout%2dkernel%2ethread%2dstate%2estack%2dadrs" title="Extracting information about the kernel / Current thread state / Kernel & user stack addresses">Kernel & user stack addresses</a></p>
</li>
<li class="style14">
<p><a href="CrashDebuggerInfoAboutKernel.guide03.html#debugging%2einfo%2dabout%2dkernel%2ethread%2dstate%2ethreadid" title="Extracting information about the kernel / Current thread state / Thread id, RAllocator instances, trap frame">Thread id, RAllocator instances, trap frame</a></p>
</li>
<li class="style14">
<p><a href="CrashDebuggerInfoAboutKernel.guide03.html#debugging%2einfo%2dabout%2dkernel%2ethread%2dstate%2etrap%2dhandler" title="Extracting information about the kernel / Current thread state / Trap handler, active scheduler, user-side exception handler">Trap handler, active scheduler and user-side exception handler</a></p>
</li>
<li class="style14">
<p><a href="CrashDebuggerInfoAboutKernel.guide03.html#debugging%2einfo%2dabout%2dkernel%2ethread%2dstate%2etemp" title="Extracting information about the kernel / Current thread state / Temporary object, temporary allocation, IPC count">Temporary object, temporary allocation, IPC count</a></p>
</li>
<li class="style14">
<p><a href="CrashDebuggerInfoAboutKernel.guide03.html#debugging%2einfo%2dabout%2dkernel%2ethread%2dstate%2enthread" title="Extracting information about the kernel / Current thread state / Underlying nanokernel thread">Underlying nanokernel thread</a></p>
</li>
<li class="style14">
<p><a href="CrashDebuggerInfoAboutKernel.guide03.html#debugging%2einfo%2dabout%2dkernel%2ethread%2dstate%2efast%2dmutexes" title="Extracting information about the kernel / Current thread state / Fast mutexes">Fast mutexes</a></p>
</li>
<li>
<p><b><a href="CrashDebuggerInfoAboutKernel.guide03.html#debugging%2einfo%2dabout%2dkernel%2ethread%2dstate%2etiming" title="Extracting information about the kernel / Current thread state / Timing, request semaphore count">Timing, request semaphore count</a></b></p>
</li>
</ul>
</div>
<div class="Head3">
<h3><span class="Bodytext"><a name="debugging%2einfo%2dabout%2dkernel%2ethread%2dstate%2ethread%2dobject"></a></span>Thread object and access count</h3>
</div><div>
<p class="CodeBlock">THREAD at 64039408 VPTR=f803423c AccessCount=3 Owner=64038d5c</p>
<p>The THread at field contains a pointer to the
DThread object representing the thread.</p>
<p>The AccessCount field contains the reference count
on the thread object.</p>
<p>The owner field contains a pointer to the object
that owns this DThread object.</p>
</div>
<div class="Head3">
<h3><span class="Bodytext"><a name="debugging%2einfo%2dabout%2dkernel%2ethread%2dstate%2ename"></a></span>The thread name</h3>
</div><div>
<p class="CodeBlock">Full name test2.exe::Main</p>
<p>The thread name is the part after the colons. The part before the
colons is the process name. This means that the thread is called
<b>Main</b> inside the process <b>test2.exe</b>.</p>
</div>
<div class="Head3">
<h3><span class="Bodytext"><a name="debugging%2einfo%2dabout%2dkernel%2ethread%2dstate%2estate"></a></span>The thread state, exit information, priority</h3>
</div><div>
<p class="CodeBlock">Thread MState READY<br>Default priority 16 WaitLink Priority 16<br>ExitInfo 2,100,USER</p>
<p>The information that characterises the thread exit is described
by ExitInfo; this is shown as exit type, exit reason and exit
category. In this example:</p>
<ul>
<li>
<p>the thread has panicked, as indicated by: <b>exit type
2</b>; See also TExitType.</p>
</li>
<li>
<p>the panic category was: <b>USER</b></p>
</li>
<li>
<p>the panic number was:<b>100</b></p>
</li>
<li>
<p>the thread was running or it was in a ready-to-run state:
<b>MState READY</b></p>
</li>
</ul>
<p>The priority shown is for the underlying thread, see also
<a href="CrashDebugger_cmd_m.guide.html" title="Process, thread, stack and memory useful information / Process and thread priorities">Process and thread priorities</a>.</p>
</div>
<div class="Head3">
<h3><span class="Bodytext"><a name="debugging%2einfo%2dabout%2dkernel%2ethread%2dstate%2eflags"></a></span>Thread flags</h3>
</div><div>
<p class="CodeBlock">Flags 00000004, Handles 640330bc</p>
<p>The Flags field contains information about the state
of the thread. The possible values in this field are defined by the
KThread... constants in u32std.h. While the symbols
are internal to Symbian OS, the following table summarises the values and their
meaning.</p>
<table cellpadding="1" border="0" cellspacing="0"><tr><td
class="TableWrap"><table cellpadding="5" cellspacing="1"
border="0"><tr valign="top"><td class="Cell">
<p><b>Symbol</b></p></td><td class="Cell">
<p><b>Value</b></p></td><td class="Cell">
<p><b>Meaning</b></p></td></tr>
<tr valign="top"><td class="Cell">
<p>KThreadFlagProcessCritical</p></td><td class="Cell">
<p>0x00000001</p></td><td class="Cell">
<p>A thread panic causes the process to
panic.</p></td></tr>
<tr valign="top"><td class="Cell">
<p>KThreadFlagProcessPermanent</p></td><td class="Cell">
<p>0x00000002</p></td><td class="Cell">
<p>If the thread exits for any reason, then this causes the
process to exit.</p></td></tr>
<tr valign="top"><td class="Cell">
<p>KThreadFlagSystemCritical</p></td><td class="Cell">
<p>0x00000004</p></td><td class="Cell">
<p>If the thread panics, then this causes the entire system to
reboot.</p></td></tr>
<tr valign="top"><td class="Cell">
<p>KThreadFlagSystemPermanent</p></td><td class="Cell">
<p>0x00000008</p></td><td class="Cell">
<p>If the thread exits for any reason, then this causes the
entire system to reboot.</p></td></tr>
<tr valign="top"><td class="Cell">
<p>KThreadFlagOriginal</p></td><td class="Cell">
<p>0x00000010</p></td><td class="Cell">
<p>Reserved for future use.</p></td></tr>
<tr valign="top"><td class="Cell">
<p>KThreadFlagLastChance</p></td><td class="Cell">
<p>0x00000020</p></td><td class="Cell">
<p>Set if the thread is currently handling an
exception.</p></td></tr>
</table></td></tr></table>
</div>
<div class="Head3">
<h3><span class="Bodytext"><a name="debugging%2einfo%2dabout%2dkernel%2ethread%2dstate%2ehandles"></a></span>Handles</h3>
</div><div>
<p class="CodeBlock">Flags 00000004, Handles 640330bc</p>
<p>The Handles field contains the address of a
DObjectIx object that contains the handles owned by the
thread.</p>
</div>
<div class="Head3">
<h3><span class="Bodytext"><a name="debugging%2einfo%2dabout%2dkernel%2ethread%2dstate%2estack%2dadrs"></a></span>Kernel & user stack addresses</h3>
</div><div>
<p class="CodeBlock">Supervisor stack base 6571f000 size 1000<br>User stack base 00402000 size 2000</p>
<p>These fields give the base address and size, in bytes, of the
kernel and user stacks respectively.</p>
</div>
<div class="Head3">
<h3><span class="Bodytext"><a name="debugging%2einfo%2dabout%2dkernel%2ethread%2dstate%2ethreadid"></a></span>Thread id, RAllocator instances, trap frame</h3>
</div><div>
<p class="CodeBlock">Id=26, Alctr=00600000, Created alctr=00600000, Frame=00000000</p>
<p>The Id field contains the thread id.</p>
<p>The Alctr field contains a pointer to the current RAllocator instance used for heap allocation.</p>
<p>The Created alctr field contains a pointer to the
original RAllocator instance used for heap allocation.
This may be different from the current instance if User::SwitchAllocator() has been called.</p>
<p>The Frame field contains a pointer to the current
trap frame, an instance of the TTrap class, on the cleanup
stack.</p>
</div>
<div class="Head3">
<h3><span class="Bodytext"><a name="debugging%2einfo%2dabout%2dkernel%2ethread%2dstate%2etrap%2dhandler"></a></span>Trap handler, active scheduler, user-side exception
handler</h3>
</div><div>
<p class="CodeBlock">Trap handler=00000000, ActiveScheduler=00000000, Exception handler=00000000</p>
<p>The Trap handler field contains a pointer to the
current trap handler, an instance of TTrapHandler, for the
cleanup stack.</p>
<p>The ActiveScheduler field contains a pointer to the
current active scheduler.</p>
<p> The Exception handler field contains a pointer to
the current user-side exception handler.</p>
</div>
<div class="Head3">
<h3><span class="Bodytext"><a name="debugging%2einfo%2dabout%2dkernel%2ethread%2dstate%2etemp"></a></span>Temporary object, temporary allocation, IPC
count</h3>
</div><div>
<p class="CodeBlock">TempObj=00000000 TempAlloc=00000000 IpcCount=00000000</p>
<p>The Tempobj field contains a pointer to an instance
of a DObject derived class that must be closed when the
thread terminates.</p>
<p>The TempAlloc field contains a pointer to a kernel
heap cell that must be freed when the thread terminates. Both this and
Tempobj are used to avoid leaks if the thread terminates
unexpectedly.</p>
<p>The IpcCount field contains the number of messages
currently queued to this thread.</p>
</div>
<div class="Head3">
<h3><span class="Bodytext"><a name="debugging%2einfo%2dabout%2dkernel%2ethread%2dstate%2enthread"></a></span>Underlying nanokernel thread</h3>
</div><div>
<p class="CodeBlock">NThread @ 640396b0 Pri 16 NState READY<br>Next=640396b0 Prev=640396b0 Att=03 iUserContextType=0b</p>
<p>The NThread field contains a pointer to the
underlying nanokernel thread object, an instance of the
NThread class.</p>
<p>The Pri field contains the current priority of the
underlying nanokernel thread.</p>
<p> The NState field shows the current state of the
underlying nanokernel thread. Note that this state is often referred to as the
N-state, as compared to the to M-state, the state of a Symbian OS thread. See
the <a href="CrashDebugger_cmd_m.guide.html" title="Process, thread, stack and memory useful information / Thread state summary">Thread state summary</a>.</p>
<p>The Next field points to the next nanokernel thread
object.</p>
<p>The Prev field points to the previous nanokernel
thread object.</p>
<p>The Att field contains the nanokernel thread
attributes, which is an 8-bit mask that controls how the thread is scheduled in
certain cases. Two attributes are defined:</p><table cellpadding="1" border="0" cellspacing="0"><tr><td
class="TableWrap"><table cellpadding="5" cellspacing="1"
border="0"><tr valign="top"><td class="Cell">
<p> KThreadAttImplicitSystemLock</p></td><td class="Cell">
<p> This attribute signifies that the thread may not be
scheduled if another thread currently holds the system lock, unless the the
former thread holds another fast mutex. This attribute is used in implementing
address space switching in the moving memory model and also in implementing
change of user context in order to allow exceptions to be raised on other
threads.</p></td></tr><tr valign="top"><td class="Cell">
<p>KThreadAttAddressSpace</p></td><td class="Cell">
<p>This attribute signifies that the thread may require a
change of address space to schedule it. This attribute is used in conjunction
with the thread’s iAddressSpace field; if this does not match the
scheduler’s iAddressSpace field at the point where the thread is
scheduled an address space switch will occur. Note that this is not required if
the address space change is limited to the ARM domain permissions since these
are saved and restored as part of the thread context.</p></td></tr></table></td></tr></table>
</div>
<div class="Head3">
<h3><span class="Bodytext"><a name="debugging%2einfo%2dabout%2dkernel%2ethread%2dstate%2efast%2dmutexes"></a></span>Fast mutexes</h3>
</div><div>
<p class="CodeBlock">HeldFM=00000000 WaitFM=00000000 AddrSp=64038d5c</p>
<p>The HeldFM field contains a pointer to the fast
mutex held by this thread; this is NULL if no fast mutext was held.</p>
<p>The WaitFM field contains a pointer to the fast
mutex that this thread was waiting on; this is NULL if this thread was not
waiting on a fast mutex.</p>
<p>The AddrSp field is the address space identifier
used by the scheduler to determine whether an address space change is required
when scheduling in a new thread.</p>
</div>
<div class="Head3">
<h3><span class="Bodytext"><a name="debugging%2einfo%2dabout%2dkernel%2ethread%2dstate%2etiming"></a></span>Timing, request semaphore count</h3>
</div><div>
<p class="CodeBlock">Time=17 Timeslice=20 ReqCount=0</p>
<p>The Time field contains the number of nanokernel
ticks, usually in milliseconds, to go before the thread is preempted.</p>
<p>The Timeslice field contains the maximum number of
ticks for which the thread can run before being preempted.</p>
<p>The ReqCount contains the request semaphore counter.
If the value is negative, then the thread is blocked waiting for a request to
complete; if it is positive, then one or more requests have completed.</p>
</div><div class="Head3">
<h3><span class="Bodytext"><a name="debugging%2einfo%2dabout%2dkernel%2ethread%2dstate%2esuspend"></a></span>Suspend count, critical section counter, register
values</h3>
</div>
<div>
<p class="CodeBlock">SuspendCount=0 CsCount=1 CsFunction=fffffffe<br>SavedSP=6571ff34 ExtraContext=00000000 ExtraContextSize=0000<br>DACR 63990000<br>R13_USR 6571ff88 R14_USR f8025bc0 SPSR_SVC 10000004<br> R4 f8033794 R5 64039408 R6 640396b0 R7 f8028518<br> R8 640396b0 R9 640396b0 R10 00000000 R11 f80284d8<br> PC 00000000</p>
<p>The SuspendCount field contains the number of times
that the thread has been suspended.</p>
<p>The CsCount field critical section counter. When
this value is greater than zero, then the thread is in a critical section and
cannot be suspended or killed.</p>
<p>The remaining content is a list of register values. <em>Note
that they are not the register values when the thread panicked.</em> They are
the values in the registers the last time that this thread was
pre-empted.</p>
</div>
<h5>Related tasks</h5>
<ul>
<li><a href="CrashDebuggerInfoAboutKernel.guide.html">Extracting Kernel Information</a> </li>
<li><a href="CrashDebuggerInfoAboutKernel.guide02.html">Scheduler State</a></li>
<li><a href="CrashDebuggerInfoAboutKernel.guide04.html">Current Process State</a></li>
<li><a href="CrashDebuggerInfoAboutKernel.guide05.html">Current Data Section Process</a></li>
</ul>
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