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/* -----------------------------------------------------------------------------
*
* (c) The GHC Team, 1998-1999
*
* The definitions for Thread State Objects.
*
* ---------------------------------------------------------------------------*/
#ifndef TSO_H
#define TSO_H
#if DEBUG
#define TSO_MAGIC 4321
#endif
typedef struct {
StgInt pri;
StgInt magic;
StgInt sparkname;
rtsTime startedat;
rtsBool exported;
StgInt basicblocks;
StgInt allocs;
rtsTime exectime;
rtsTime fetchtime;
rtsTime fetchcount;
rtsTime blocktime;
StgInt blockcount;
rtsTime blockedat;
StgInt globalsparks;
StgInt localsparks;
rtsTime clock;
} StgTSOStatBuf;
/*
* PROFILING info in a TSO
*/
typedef struct {
CostCentreStack *CCCS; /* thread's current CCS */
} StgTSOProfInfo;
/*
* There is no TICKY info in a TSO at this time.
*/
/*
* Thread IDs are 32 bits.
*/
typedef StgWord32 StgThreadID;
#define tsoDirty(tso) ((tso)->flags & TSO_DIRTY)
#define tsoLocked(tso) ((tso)->flags & TSO_LOCKED)
/*
* Type returned after running a thread. Values of this type
* include HeapOverflow, StackOverflow etc. See Constants.h for the
* full list.
*/
typedef unsigned int StgThreadReturnCode;
#if defined(mingw32_HOST_OS)
/* results from an async I/O request + its request ID. */
typedef struct {
unsigned int reqID;
int len;
int errCode;
} StgAsyncIOResult;
#endif
/* Reason for thread being blocked. See comment above struct StgTso_. */
typedef union {
StgClosure *closure;
struct StgTSO_ *tso;
StgInt fd; /* StgInt instead of int, so that it's the same size as the ptrs */
#if defined(mingw32_HOST_OS)
StgAsyncIOResult *async_result;
#endif
StgWord target;
} StgTSOBlockInfo;
/*
* TSOs live on the heap, and therefore look just like heap objects.
* Large TSOs will live in their own "block group" allocated by the
* storage manager, and won't be copied during garbage collection.
*/
/*
* Threads may be blocked for several reasons. A blocked thread will
* have the reason in the why_blocked field of the TSO, and some
* further info (such as the closure the thread is blocked on, or the
* file descriptor if the thread is waiting on I/O) in the block_info
* field.
*/
typedef struct StgTSO_ {
StgHeader header;
/* The link field, for linking threads together in lists (e.g. the
run queue on a Capability.
*/
struct StgTSO_* _link;
/*
NOTE!!! do not modify _link directly, it is subject to
a write barrier for generational GC. Instead use the
setTSOLink() function. Exceptions to this rule are:
* setting the link field to END_TSO_QUEUE
* putting a TSO on the blackhole_queue
* setting the link field of the currently running TSO, as it
will already be dirty.
*/
struct StgTSO_* global_link; /* Links all threads together */
StgWord16 what_next; /* Values defined in Constants.h */
StgWord16 why_blocked; /* Values defined in Constants.h */
StgWord32 flags;
StgTSOBlockInfo block_info;
StgThreadID id;
int saved_errno;
struct Task_* bound;
struct Capability_* cap;
struct StgTRecHeader_ * trec; /* STM transaction record */
/*
A list of threads blocked on this TSO waiting to throw
exceptions. In order to access this field, the TSO must be
locked using lockClosure/unlockClosure (see SMP.h).
*/
struct StgTSO_ * blocked_exceptions;
#ifdef TICKY_TICKY
/* TICKY-specific stuff would go here. */
#endif
#ifdef PROFILING
StgTSOProfInfo prof;
#endif
#ifdef mingw32_HOST_OS
StgWord32 saved_winerror;
#endif
/* The thread stack... */
StgWord32 stack_size; /* stack size in *words* */
StgWord32 max_stack_size; /* maximum stack size in *words* */
StgPtr sp;
StgWord stack[FLEXIBLE_ARRAY];
} StgTSO;
/* -----------------------------------------------------------------------------
functions
-------------------------------------------------------------------------- */
extern void dirty_TSO (Capability *cap, StgTSO *tso);
extern void setTSOLink (Capability *cap, StgTSO *tso, StgTSO *target);
/* -----------------------------------------------------------------------------
Invariants:
An active thread has the following properties:
tso->stack < tso->sp < tso->stack+tso->stack_size
tso->stack_size <= tso->max_stack_size
RESERVED_STACK_WORDS is large enough for any heap-check or
stack-check failure.
The size of the TSO struct plus the stack is either
(a) smaller than a block, or
(b) a multiple of BLOCK_SIZE
tso->why_blocked tso->block_info location
----------------------------------------------------------------------
NotBlocked NULL runnable_queue, or running
BlockedOnBlackHole the BLACKHOLE_BQ the BLACKHOLE_BQ's queue
BlockedOnMVar the MVAR the MVAR's queue
BlockedOnSTM END_TSO_QUEUE STM wait queue(s)
BlockedOnException the TSO TSO->blocked_exception
BlockedOnRead NULL blocked_queue
BlockedOnWrite NULL blocked_queue
BlockedOnDelay NULL blocked_queue
BlockedOnGA closure TSO blocks on BQ of that closure
BlockedOnGA_NoSend closure TSO blocks on BQ of that closure
tso->link == END_TSO_QUEUE, if the thread is currently running.
A zombie thread has the following properties:
tso->what_next == ThreadComplete or ThreadKilled
tso->link == (could be on some queue somewhere)
tso->su == tso->stack + tso->stack_size
tso->sp == tso->stack + tso->stack_size - 1 (i.e. top stack word)
tso->sp[0] == return value of thread, if what_next == ThreadComplete,
exception , if what_next == ThreadKilled
(tso->sp is left pointing at the top word on the stack so that
the return value or exception will be retained by a GC).
The 2 cases BlockedOnGA and BlockedOnGA_NoSend are needed in a GUM
setup only. They mark a TSO that has entered a FETCH_ME or
FETCH_ME_BQ closure, respectively; only the first TSO hitting the
closure will send a Fetch message.
Currently we have no separate code for blocking on an RBH; we use the
BlockedOnBlackHole case for that. -- HWL
---------------------------------------------------------------------------- */
/* Workaround for a bug/quirk in gcc on certain architectures.
* symptom is that (&tso->stack - &tso->header) /= sizeof(StgTSO)
* in other words, gcc pads the structure at the end.
*/
extern StgTSO dummy_tso;
#define TSO_STRUCT_SIZE \
((char *)&dummy_tso.stack - (char *)&dummy_tso.header)
#define TSO_STRUCT_SIZEW (TSO_STRUCT_SIZE / sizeof(W_))
/* this is the NIL ptr for a TSO queue (e.g. runnable queue) */
#define END_TSO_QUEUE ((StgTSO *)(void*)&stg_END_TSO_QUEUE_closure)
#endif /* TSO_H */
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