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source: trunk/kernel/kern/thread.h @ 408

Last change on this file since 408 was 408, checked in by alain, 7 years ago
Fix several bugs in the fork() syscall.
File size: 27.8 KB

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1	/*
2	* thread.h - Thread and related operations definition.
3	*
4	* Author Ghassan Almaless (2008,2009,2010,2011,2012)
5	* Alain Greiner (2016)
6	*
7	* Copyright (c) UPMC Sorbonne Universites
8	*
9	* This file is part of ALMOS-MKH.
10	*
11	* ALMOS-MKH is free software; you can redistribute it and/or modify it
12	* under the terms of the GNU General Public License as published by
13	* the Free Software Foundation; version 2.0 of the License.
14	*
15	* ALMOS-MKH is distributed in the hope that it will be useful, but
16	* WITHOUT ANY WARRANTY; without even the implied warranty of
17	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18	* General Public License for more details.
19	*
20	* You should have received a copy of the GNU General Public License
21	* along with ALMOS-MKH; if not, write to the Free Software Foundation,
22	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
23	*/
24
25	#ifndef _THREAD_H_
26	#define _THREAD_H_
27
28	#include <hal_types.h>
29	#include <shared_syscalls.h>
30	#include <hal_special.h>
31	#include <xlist.h>
32	#include <list.h>
33	#include <hal_context.h>
34	#include <spinlock.h>
35	#include <core.h>
36	#include <chdev.h>
37	#include <cluster.h>
38	#include <process.h>
39	#include <dev_ioc.h>
40	#include <dev_nic.h>
41	#include <dev_txt.h>
42	#include <dev_mmc.h>
43	#include <dev_dma.h>
44
45	/***************************************************************************************
46	* These macros are used to compose or decompose global thread identifier (TRDID)
47	* to or from cluster identifier / local thread index (CXY , LTID)
48	**************************************************************************************/
49
50	#define LTID_FROM_TRDID( trdid ) (ltid_t)(trdid & 0x0000FFFF)
51	#define CXY_FROM_TRDID( trdid ) (cxy_t)(trdid >> 16)
52	#define TRDID( cxy , ltid ) (trdid_t)((cxy << 16) \| ltid )
53
54	/***************************************************************************************
55	* This enum defines the thread types.
56	**************************************************************************************/
57
58	typedef enum
59	{
60	THREAD_USER = 0, /! user thread (pthread) /
61	THREAD_RPC = 1, /! kernel thread executing pending RPCs /
62	THREAD_DEV = 2, /! kernel thread executing I/O device commands /
63	THREAD_IDLE = 3, /! kernel idle thread /
64	}
65	thread_type_t;
66
67	/***************************************************************************************
68	* This defines the thread flags bit-vector.
69	**************************************************************************************/
70
71	#define THREAD_FLAG_LOADABLE 0x0001 /! This thread has not been executed yet /
72	#define THREAD_FLAG_DETACHED 0x0002 /! This thread is detached from parent /
73	#define THREAD_FLAG_JOIN 0x0004 /! Parent thread made a join /
74	#define THREAD_FLAG_EXIT 0x0008 /! This thread made an exit /
75	#define THREAD_FLAG_SCHED 0x0010 /! Scheduling required for this thread /
76
77	/***************************************************************************************
78	* This defines the masks associated to the thread signals.
79	**************************************************************************************/
80
81	#define THREAD_SIG_KILL 0x0001 /! This thread killed by another thread /
82	#define THREAD_SIG_SUICIDE 0x0002 /! This thread required exit /
83
84	/***************************************************************************************
85	* This defines the masks associated to the blocking causes.
86	**************************************************************************************/
87
88	#define THREAD_BLOCKED_GLOBAL 0x0001 /! thread deactivated / wait activation /
89	#define THREAD_BLOCKED_IO 0x0002 /! thread wait IO operation completion /
90	#define THREAD_BLOCKED_MAPPER 0x0004 /! thread wait mapper /
91	#define THREAD_BLOCKED_JOIN 0x0008 /! thread blocked in join / wait exit /
92	#define THREAD_BLOCKED_EXIT 0x0010 /! thread blocked in exit / wait join /
93	#define THREAD_BLOCKED_KILL 0x0020 /! thread received kill signal /
94	#define THREAD_BLOCKED_SEM 0x0040 /! thread wait semaphore /
95	#define THREAD_BLOCKED_PAGE 0x0080 /! thread wait page access /
96	#define THREAD_BLOCKED_USERSYNC 0x0100 /! thread wait POSIX (cond/mutex/barrier) /
97	#define THREAD_BLOCKED_RPC 0x0200 /! thread wait RPC completion /
98
99	#define THREAD_BLOCKED_DEV_ISR 0x4000 /! thread DEV wait ISR /
100
101	/***************************************************************************************
102	* This structure defines thread instrumentation informations.
103	**************************************************************************************/
104
105	typedef struct thread_info_s
106	{
107	uint32_t pgfault_nr; /! cumulated number of page fault /
108	uint32_t sched_nr; /! TODO ??? [AG] /
109	uint32_t u_err_nr; /! TODO ??? [AG] /
110	uint32_t m_err_nr; /! TODO ??? [AG] /
111	uint32_t tm_tmp; /! temp date to compute execution duration /
112	uint32_t tm_exec; /! TODO ??? [AG] /
113	uint32_t tm_create; /! date of the creation /
114	uint32_t tm_born; /! date of the thread loading /
115	uint32_t tm_dead; /! date of the death /
116	cycle_t tm_sleep; /! TODO ??? [AG] /
117	cycle_t tm_wait; /! TODO ??? [AG] /
118	cycle_t tm_usr; /! user execution duration /
119	cycle_t tm_sys; /! system execution duration /
120	}
121	thread_info_t;
122
123	/***************************************************************************************
124	* This structure defines a thread descriptor.
125	* It is used for both the user threads and the kernel threads.
126	* In a process, a user thread is identified by a unique TRDID (thread identifier),
127	* that is returned by the kernel to the user:
128	* - The TRDID 16 LSB bits contain the LTID (Local Thread Index).
129	* - The TRDID 16 MSB bits contain the CXY of cluster containing the thread.
130	* - The LTID is used to index the th_tbl[] array in the local process descriptor.
131	* This TRDID is computed by the process_register_thread() function, when the user
132	* thread is registered in the local copy of the process descriptor.
133	*
134	* WARNING : Don't modify the first 3 fields order, as this order is used by the
135	* hal_kentry assembly code for the TSAR architecture.
136	**************************************************************************************/
137
138	#define THREAD_SIGNATURE 0xDEADBEEF
139
140	typedef struct thread_s
141	{
142	void * cpu_context; /! pointer on CPU context switch /
143	void * fpu_context; /! pointer on FPU context switch /
144	void * uzone; /! pointer on uzone for hal_kentry /
145
146	intptr_t k_stack_base; /! kernel stack base address /
147	uint32_t k_stack_size; /! kernel stack size (bytes) /
148
149	uint32_t trdid; /! thread index (cxy.ltid) /
150	thread_type_t type; /! thread type /
151	uint32_t quantum; /! number of clock ticks given to thread /
152	uint32_t ticks_nr; /! number of ticks used /
153	uint32_t time_last_check; /! last cpu_time_stamp /
154	core_t * core; /! pointer to the owner core /
155	process_t * process; /! pointer on local process descriptor /
156	xptr_t parent; /! extended pointer on parent thread /
157
158	void * exit_value; /! exit_value used in case of join /
159
160	uint32_t local_locks; /! number of local locks owned by thread /
161	list_entry_t locks_root; /! root of local locks list /
162
163	remote_spinlock_t * flags_lock; /! lock protecting the flags /
164
165	uint32_t remote_locks; /! number of local locks owned by thread /
166	xlist_entry_t xlocks_root; /! root of remote locks list /
167
168	intptr_t u_stack_base; /! user stack base address /
169	uint32_t u_stack_size; /! user stack size (bytes) /
170
171	void * entry_func; /! pointer on entry function /
172	void * entry_args; /! pointer on entry function arguments /
173
174	uint32_t flags; /! bit vector of flags /
175	uint32_t signals; /! bit vector of (KILL / SUICIDE) signals /
176	uint32_t blocked; /! bit vector of blocking causes /
177
178	error_t errno; /! errno value set by last system call /
179	uint32_t utls; /! user thread local storage /
180
181	bool_t fork_user; /! user defined placement for next fork() /
182	cxy_t fork_cxy; /! target cluster for next fork() /
183
184	xlist_entry_t children_root; /! root of list of attached children /
185	uint32_t children_nr; /! number of attached children threads /
186	remote_spinlock_t * children_lock; /! lock protecting the children list /
187
188	xlist_entry_t brothers_list; /! list of attached threads to same parent /
189
190	list_entry_t sched_list; /! member of threads attached to same core /
191
192	chdev_t * chdev; /! chdev pointer (for a DEV thread only) /
193
194	reg_t save_sr; /! used by sched_yield() function /
195
196	ioc_command_t ioc_cmd; /! IOC device generic command /
197	txt_command_t txt_cmd; /! TXT device generic command /
198	nic_command_t nic_cmd; /! NIC device generic command /
199	mmc_command_t mmc_cmd; /! MMC device generic command /
200	dma_command_t dma_cmd; /! DMA device generic command /
201
202	cxy_t rpc_client_cxy; /! client cluster index (for a RPC thread) /
203
204	xlist_entry_t wait_list; /! member of threads blocked on same cond /
205
206	thread_info_t info; /! embedded thread_info_t /
207
208	uint32_t signature; /! for kernel stack overflow detection /
209	}
210	thread_t;
211
212	/***************************************************************************************
213	* This macro returns a pointer on the calling thread from the core hardware register.
214	**************************************************************************************/
215
216	#define CURRENT_THREAD (hal_get_current_thread())
217
218	/***************************************************************************************
219	* This function returns a printable string for a thread type.
220	***************************************************************************************
221	* @ type : thread type.
222	* returns pointer on string.
223	**************************************************************************************/
224	char * thread_type_str( uint32_t type );
225
226	/***************************************************************************************
227	* This function is used by the pthread_create() system call to create a "new" thread
228	* in an existing process. It allocates memory for an user thread descriptor in the
229	* local cluster, and initializes it from information contained in the arguments.
230	* The CPU context is initialized from scratch. If required by the <attr> argument,
231	* the new thread is attached to the core specified in <attr>.
232	* It is registered in the local process descriptor specified by the <pid> argument.
233	* The thread descriptor pointer is returned to allow the parent thread to register it
234	* in its children list.
235	* The THREAD_BLOCKED_GLOBAL bit is set => the thread must be activated to start.
236	***************************************************************************************
237	* @ pid : process identifier.
238	* @ start_func : pointer on entry function.
239	* @ start_args : pointer on function argument (can be NULL).
240	* @ attr : pointer on pthread attributes descriptor.
241	* @ new_thread : [out] address of buffer for new thread descriptor pointer.
242	* @ returns 0 if success / returns ENOMEM if error.
243	**************************************************************************************/
244	error_t thread_user_create( pid_t pid,
245	void * start_func,
246	void * start_arg,
247	pthread_attr_t * attr,
248	thread_t ** new_thread );
249
250	/***************************************************************************************
251	* This function is used by the sys_fork() system call to create the "child" thread
252	* in the local cluster. It allocates memory for a thread descriptor, and initializes
253	* it from the "parent" thread descriptor defined by the <parent_thread_xp> argument.
254	* The new thread is attached to the core that has the lowest load in local cluster.
255	* It is registered in the "child" process defined by the <child_process> argument.
256	* This new thread inherits its user stack from the parent thread, as it uses the
257	* Copy-On-Write mechanism to get a private stack when required.
258	* The content of the parent kernel stack is copied into the child kernel stack, as
259	* the Copy-On-Write mechanism cannot be used for kernel segments (because kernel
260	* uses physical addressing on some architectures).
261	* The CPU and FPU execution contexts are created and linked to the new thread.
262	* but the actual context copy is NOT done, and must be done by by the sys_fork().
263	* The THREAD_BLOCKED_GLOBAL bit is set => the thread must be activated to start.
264	***************************************************************************************
265	* @ parent_thread_xp : extended pointer on parent thread descriptor.
266	* @ child_process : local pointer on child process descriptor.
267	* @ child_thread : [out] address of buffer for child thread descriptor pointer.
268	* @ returns 0 if success / returns -1 if error.
269	**************************************************************************************/
270	error_t thread_user_fork( xptr_t parent_thread_xp,
271	process_t * child_process,
272	thread_t ** child_thread );
273
274	/***************************************************************************************
275	* This function allocates memory for a kernel thread descriptor in the local cluster,
276	* and initializes it from arguments values.
277	* It is called by kernel_init() to statically create all DEV server threads
278	* It is also called to dynamically create RPC threads when required.
279	* The THREAD_BLOCKED_GLOBAL bit is set, and the thread must be activated to start.
280	***************************************************************************************
281	* @ new_thread : address of buffer for new thread pointer.
282	* @ type : kernel thread type.
283	* @ func : pointer on function.
284	* @ args : function arguments.
285	* @ core_lid : local core index.
286	* @ returns 0 if success / returns ENOMEM if error
287	**************************************************************************************/
288	error_t thread_kernel_create( thread_t ** new_thread,
289	thread_type_t type,
290	void * func,
291	void * args,
292	lid_t core_lid );
293
294	/***************************************************************************************
295	* This function initializes an existing thread descriptor from arguments values.
296	* The THREAD_BLOCKED_GLOBAL bit is set, and the thread must be activated to start.
297	* It is called by the kernel_init() function to initialize the IDLE thread.
298	***************************************************************************************
299	* @ thread : pointer on existing thread descriptor.
300	* @ type : kernel thread type.
301	* @ func : pointer on function.
302	* @ args : function arguments.
303	* @ core_lid : local core index.
304	* @ returns 0 if success / returns EINVAL if error
305	**************************************************************************************/
306	error_t thread_kernel_init( thread_t * thread,
307	thread_type_t type,
308	void * func,
309	void * args,
310	lid_t core_lid );
311
312	/***************************************************************************************
313	* This function releases the physical memory allocated for a thread descriptor
314	* in the local cluster. It can be used for both an user and a kernel thread.
315	* The physical memory dynamically allocated in the HEAP or MMAP zones by an user
316	* thread will be released when the process is killed, and the page table flushed.
317	***************************************************************************************
318	* @ thread : pointer on the thread descriptor to release.
319	**************************************************************************************/
320	void thread_destroy( thread_t * thread );
321
322	/***************************************************************************************
323	* This function defines the code of the thread executed by all cores after kernel_init,
324	* or when no other thread is runnable for a given core.
325	*
326	* TODO: In the TSAR architecture, it enters an infinite loop, in wich it forces
327	* the core in sleep (low-power) mode. Any IRQ will force the core to exit this sleep
328	* mode, but no ISR is executed.
329	* TODO: We must analyse if we have the same behaviour for I86 architectures...
330	**************************************************************************************/
331	void thread_idle_func();
332
333	/***************************************************************************************
334	* This function registers a child thread in the global list of attached
335	* children threads of a parent thread.
336	* It does NOT take a lock, as this function is always called by the parent thread.
337	***************************************************************************************
338	* @ parent_xp : extended pointer on the parent thread descriptor.
339	* @ child_xp : extended pointer on the child thread descriptor.
340	**************************************************************************************/
341	void thread_child_parent_link( xptr_t parent_xp,
342	xptr_t child_xp );
343
344	/***************************************************************************************
345	* This function removes an user thread from the parent thread global list
346	* of attached children threads.
347	***************************************************************************************
348	* @ parent_xp : extended pointer on the parent thread descriptor.
349	* @ child_xp : extended pointer on the child thread descriptor.
350	**************************************************************************************/
351	void thread_child_parent_unlink( xptr_t parent_xp,
352	xptr_t child_xp );
353
354	/***************************************************************************************
355	* This function atomically sets a signal in a thread descriptor.
356	***************************************************************************************
357	* @ thread : local pointer on target thread.
358	*s released all locks @ mask : mask on selected signal.
359	**************************************************************************************/
360	inline void thread_set_signal( thread_t * thread,
361	uint32_t mask );
362
363	/***************************************************************************************
364	* This function resets a signal in a thread descriptor.
365	***************************************************************************************
366	* @ thread : local pointer on target thread.
367	* @ mask : mask on selected signal.
368	**************************************************************************************/
369	inline void thread_reset_signal( thread_t * thread,
370	uint32_t mask );
371
372	/***************************************************************************************
373	* This function checks if the calling thread can deschedule.
374	***************************************************************************************
375	* @ returns true if no locks taken.
376	**************************************************************************************/
377	inline bool_t thread_can_yield();
378
379	/***************************************************************************************
380	* This function implements the delayed descheduling mechanism : It is called by
381	* all lock release functions, and calls the sched_yield() function when all locks
382	* have beeen released and the calling thread THREAD_FLAG_SCHED flag is set.
383	**************************************************************************************/
384	void thread_check_sched();
385
386	/***************************************************************************************
387	* This function is used by the calling thread to suicide.
388	* All locks must be previously released. The scenario depends on the DETACHED flag.
389	* if detached :
390	* 1) the calling thread sets the SIG_SUICIDE bit in the "signals" bit_vector,
391	* registers the BLOCKED_GLOBAL bit in the "blocked" bit_vector, and deschedule.
392	* 2) the scheduler, detecting the SIG_SUICIDE bit, remove the thread from the
393	* scheduler list, remove the thread from its process, and destroys the thread.
394	* if attached :
395	* 1) the calling thread simply sets the BLOCKED_EXIT bit in the "blocked" bit vector
396	* and deschedule.
397	* 2) The SIG_KILL bit and BLOCKED_SIGNAL bits are set by the parent thread when
398	* executing the pthread_join(), and detecting the BLOCKED_EXIT bit.
399	* The scenario is a standard kill as described below.
400	***************************************************************************************
401	* @ returns 0 if success / returns EINVAL if locks_count is not zero.
402	**************************************************************************************/
403	error_t thread_exit();
404
405	/***************************************************************************************
406	* This function request to kill a local target thread, with the following scenario:
407	* 1. This function set the BLOCKED_GLOBAL bit in target thread "blocked" bit_vector,
408	* set the SIG_KILL bit in target thread "signals" bit_vector, and send an IPI
409	* to the target thread core to force scheduling.
410	* 2. The scheduler, detecting the SIG_KILL set, removes the thread from the scheduler
411	* list, and reset the SIG_KILL bit to acknowledge the killer.
412	* 3. The caller of this function, (such as the process_kill() function), must poll
413	* SIG_KILL bit until reset, detach the thread from its parent if the thread is
414	* attached, remove the thread from its process, and destroys the thread.
415	*
416	* NOTE: The third step must be done by the caller to allows the process_kill()
417	* function to parallelize the work on all schedulers in a given cluster.
418	***************************************************************************************
419	* @ thread : local pointer on the target thread.
420	**************************************************************************************/
421	void thread_kill( thread_t * thread );
422
423	/***************************************************************************************
424	* This function registers a blocking cause in the target thread "blocked" bit vector.
425	* Warning : this function does not deschedule the calling thread, and the descheduling
426	* must be explicitely forced by a sched_yield().
427	***************************************************************************************
428	* @ thread : local pointer on target thread descriptor.
429	* @ cause : mask defining the cause (one hot).
430	**************************************************************************************/
431	void thread_block( thread_t * thread,
432	uint32_t cause );
433
434	/***************************************************************************************
435	* This function resets the bit identified by the cause argument in the "blocked"
436	* bit vector of a remote thread descriptor, using an atomic access.
437	* We need an extended pointer, because the client thread of an I/O operation on a
438	* given device is not in the same cluster as the associated device descriptor.
439	* Warning : this function does not reschedule the remote thread.
440	* The scheduling can be forced by sending an IPI to the core running the remote thread.
441	***************************************************************************************
442	* @ thread : extended pointer on the remote thread.
443	* @ cause : mask defining the cause (one hot).
444	* @ return non zero if the bit-vector was actually modified / return 0 otherwise
445	**************************************************************************************/
446	uint32_t thread_unblock( xptr_t thread,
447	uint32_t cause );
448
449	/***************************************************************************************
450	* This function updates the calling thread user_time counter, and resets the thread
451	* cycles counter.
452	* TODO This function is not implemented.
453	***************************************************************************************
454	* @ thread : local pointer on target thread.
455	**************************************************************************************/
456	void thread_user_time_update( thread_t * thread );
457
458	/**************************************************************************************n
459	* This function updates the calling thread kernel_time counter, and resets the thread
460	* cycles counter.
461	* TODO This function is not implemented.
462	***************************************************************************************
463	* @ thread : local pointer on target thread.
464	**************************************************************************************/
465	void thread_kernel_time_update( thread_t * thread );
466
467	/***************************************************************************************
468	* This function handles all pending signals for the thread identified by the <thread>
469	* argument. It is called each time the core exits the kernel, after handling an
470	* interrupt, exception or syscall.
471	* TODO This function is not implemented.
472	***************************************************************************************
473	* @ thread : local pointer on target thread.
474	**************************************************************************************/
475	void thread_signals_handle( thread_t * thread );
476
477	/***************************************************************************************
478	* This function returns the extended pointer on a thread descriptor identified
479	* by its thread identifier, and process identifier.
480	* It can be called by any thread running in any cluster.
481	***************************************************************************************
482	* @ pid : process identifier.
483	* @ trdid : thread identifier.
484	* @ return the extended pointer if thread found / return XPTR_NULL if not found.
485	**************************************************************************************/
486	xptr_t thread_get_xptr( pid_t pid,
487	trdid_t trdid );
488
489
490	#endif /* _THREAD_H_ */

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