Context Navigation

kernel.cfa@ 77d601f

Visit:

ADT arm-eh ast-experimental enum forall-pointer-decay jacob/cs343-translation new-ast-unique-expr pthread-emulation qualifiedEnum

Last change on this file since 77d601f was 55d6affb, checked in by Thierry Delisle <tdelisle@…>, 5 years ago
Fixed stupid copy past mistake where I used eventfd_read (wait) instead of eventfd_write (signal).
Property mode set to `100644`
File size: 23.9 KB

Rev	Line
[8118303]	1	//
	2	// Cforall Version 1.0.0 Copyright (C) 2016 University of Waterloo
	3	//
	4	// The contents of this file are covered under the licence agreement in the
	5	// file "LICENCE" distributed with Cforall.
	6	//
	7	// kernel.c --
	8	//
	9	// Author : Thierry Delisle
[75f3522]	10	// Created On : Tue Jan 17 12:27:26 2017
[6b0b624]	11	// Last Modified By : Peter A. Buhr
[0190480]	12	// Last Modified On : Mon Aug 31 07:08:20 2020
	13	// Update Count : 71
[8118303]	14	//
	15
[2026bb6]	16	#define __cforall_thread__
[4069faad]	17	// #define __CFA_DEBUG_PRINT_RUNTIME_CORE__
[2026bb6]	18
[8118303]	19	//C Includes
[214e8da]	20	#include <errno.h>
[9d944b2]	21	#include <stdio.h>
[58b6d1b]	22	#include <signal.h>
[9d944b2]	23	#include <unistd.h>
[dddb3dd0]	24	extern "C" {
	25	#include <sys/eventfd.h>
	26	}
[8118303]	27
	28	//CFA Includes
[73abe95]	29	#include "kernel_private.hfa"
	30	#include "preemption.hfa"
[8118303]	31
	32	//Private includes
	33	#define __CFA_INVOKE_PRIVATE__
	34	#include "invoke.h"
	35
[4069faad]	36
[deca0f5]	37	//-----------------------------------------------------------------------------
	38	// Some assembly required
[1805b1b]	39	#if defined( __i386 )
[deca0f5]	40	// mxcr : SSE Status and Control bits (control bits are preserved across function calls)
	41	// fcw : X87 FPU control word (preserved across function calls)
	42	#define __x87_store \
	43	uint32_t __mxcr; \
	44	uint16_t __fcw; \
	45	__asm__ volatile ( \
	46	"stmxcsr %0\n" \
	47	"fnstcw %1\n" \
	48	: "=m" (__mxcr),\
	49	"=m" (__fcw) \
	50	)
	51
	52	#define __x87_load \
	53	__asm__ volatile ( \
	54	"fldcw %1\n" \
	55	"ldmxcsr %0\n" \
	56	::"m" (__mxcr),\
	57	"m" (__fcw) \
	58	)
	59
	60	#elif defined( __x86_64 )
	61	#define __x87_store \
	62	uint32_t __mxcr; \
	63	uint16_t __fcw; \
	64	__asm__ volatile ( \
	65	"stmxcsr %0\n" \
	66	"fnstcw %1\n" \
	67	: "=m" (__mxcr),\
	68	"=m" (__fcw) \
	69	)
	70
	71	#define __x87_load \
	72	__asm__ volatile ( \
	73	"fldcw %1\n" \
	74	"ldmxcsr %0\n" \
	75	:: "m" (__mxcr),\
	76	"m" (__fcw) \
	77	)
	78
[0190480]	79	#elif defined( __arm__ )
	80	#define __x87_store
	81	#define __x87_load
	82
	83	#elif defined( __aarch64__ )
[74f5c83]	84	#define __x87_store \
	85	uint32_t __fpcntl[2]; \
	86	__asm__ volatile ( \
	87	"mrs x9, FPCR\n" \
	88	"mrs x10, FPSR\n" \
	89	"stp x9, x10, %0\n" \
	90	: "=m" (__fpcntl) : : "x9", "x10" \
	91	)
	92
	93	#define __x87_load \
	94	__asm__ volatile ( \
	95	"ldp x9, x10, %0\n" \
	96	"msr FPSR, x10\n" \
	97	"msr FPCR, x9\n" \
	98	: "=m" (__fpcntl) : : "x9", "x10" \
	99	)
	100
[deca0f5]	101	#else
[0190480]	102	#error unsupported hardware architecture
[deca0f5]	103	#endif
	104
[e660761]	105	extern $thread * mainThread;
	106	extern processor * mainProcessor;
[2ac095d]	107
[92e7631]	108	//-----------------------------------------------------------------------------
	109	// Kernel Scheduling logic
	110	static $thread * __next_thread(cluster * this);
[1eb239e4]	111	static $thread * __next_thread_slow(cluster * this);
[92e7631]	112	static void __run_thread(processor * this, $thread * dst);
[e873838]	113	static void __wake_one(cluster * cltr);
[1eb239e4]	114
	115	static void push (__cluster_idles & idles, processor & proc);
	116	static void remove(__cluster_idles & idles, processor & proc);
	117	static [unsigned idle, unsigned total, * processor] query( & __cluster_idles idles );
	118
[dddb3dd0]	119	extern void __cfa_io_start( processor * );
	120	extern void __cfa_io_drain( processor * );
	121	extern void __cfa_io_flush( processor * );
	122	extern void __cfa_io_stop ( processor * );
	123	static inline void __maybe_io_drain( processor * );
	124
	125	extern void __disable_interrupts_hard();
	126	extern void __enable_interrupts_hard();
[c84e80a]	127
[75f3522]	128	//=============================================================================================
	129	// Kernel Scheduling logic
	130	//=============================================================================================
[8fcbb4c]	131	//Main of the processor contexts
[83a071f9]	132	void main(processorCtx_t & runner) {
[21184e3]	133	// Because of a bug, we couldn't initialized the seed on construction
	134	// Do it here
[8fc652e0]	135	__cfaabi_tls.rand_seed ^= rdtscl();
	136	__cfaabi_tls.ready_rng.fwd_seed = 25214903917_l64u * (rdtscl() ^ (uintptr_t)&runner);
[f2384c9a]	137	__tls_rand_advance_bck();
[21184e3]	138
[83a071f9]	139	processor * this = runner.proc;
[094476d]	140	verify(this);
[c81ebf9]	141
[dddb3dd0]	142	__cfa_io_start( this );
	143
[4069faad]	144	__cfadbg_print_safe(runtime_core, "Kernel : core %p starting\n", this);
[28d73c1]	145	#if !defined(__CFA_NO_STATISTICS__)
	146	if( this->print_halts ) {
	147	__cfaabi_bits_print_safe( STDOUT_FILENO, "Processor : %d - %s (%p)\n", this->id, this->name, (void*)this);
	148	}
	149	#endif
[b798713]	150
[75f3522]	151	{
[c81ebf9]	152	// Setup preemption data
	153	preemption_scope scope = { this };
	154
[325e6ea]	155	#if !defined(__CFA_NO_STATISTICS__)
	156	unsigned long long last_tally = rdtscl();
	157	#endif
	158
	159
[4069faad]	160	__cfadbg_print_safe(runtime_core, "Kernel : core %p started\n", this);
[8118303]	161
[ac2b598]	162	$thread * readyThread = 0p;
[1eb239e4]	163	MAIN_LOOP:
	164	for() {
[dddb3dd0]	165	// Check if there is pending io
	166	__maybe_io_drain( this );
	167
[92e7631]	168	// Try to get the next thread
[8c50aed]	169	readyThread = __next_thread( this->cltr );
[75f3522]	170
[1eb239e4]	171	if( !readyThread ) {
[dddb3dd0]	172	__cfa_io_flush( this );
[1eb239e4]	173	readyThread = __next_thread_slow( this->cltr );
	174	}
[4e6fb8e]	175
[1eb239e4]	176	HALT:
	177	if( !readyThread ) {
	178	// Don't block if we are done
	179	if( __atomic_load_n(&this->do_terminate, __ATOMIC_SEQ_CST) ) break MAIN_LOOP;
[c81ebf9]	180
[1eb239e4]	181	#if !defined(__CFA_NO_STATISTICS__)
	182	__tls_stats()->ready.sleep.halts++;
	183	#endif
[398e8e9]	184
[1eb239e4]	185	// Push self to idle stack
	186	push(this->cltr->idles, * this);
[398e8e9]	187
[1eb239e4]	188	// Confirm the ready-queue is empty
	189	readyThread = __next_thread_slow( this->cltr );
	190	if( readyThread ) {
	191	// A thread was found, cancel the halt
	192	remove(this->cltr->idles, * this);
	193
	194	#if !defined(__CFA_NO_STATISTICS__)
	195	__tls_stats()->ready.sleep.cancels++;
	196	#endif
	197
	198	// continue the mai loop
	199	break HALT;
	200	}
	201
	202	#if !defined(__CFA_NO_STATISTICS__)
	203	if(this->print_halts) {
	204	__cfaabi_bits_print_safe( STDOUT_FILENO, "PH:%d - %lld 0\n", this->id, rdtscl());
	205	}
	206	#endif
	207
[dddb3dd0]	208	__cfadbg_print_safe(runtime_core, "Kernel : core %p waiting on eventfd %d\n", this, this->idle);
	209
	210	__disable_interrupts_hard();
	211	eventfd_t val;
	212	eventfd_read( this->idle, &val );
	213	__enable_interrupts_hard();
[1eb239e4]	214
	215	#if !defined(__CFA_NO_STATISTICS__)
	216	if(this->print_halts) {
	217	__cfaabi_bits_print_safe( STDOUT_FILENO, "PH:%d - %lld 1\n", this->id, rdtscl());
	218	}
	219	#endif
	220
	221	// We were woken up, remove self from idle
	222	remove(this->cltr->idles, * this);
	223
	224	// DON'T just proceed, start looking again
	225	continue MAIN_LOOP;
[64a7146]	226	}
[1eb239e4]	227
	228	/* paranoid */ verify( readyThread );
	229
[dddb3dd0]	230	// Reset io dirty bit
	231	this->io.dirty = false;
	232
[1eb239e4]	233	// We found a thread run it
	234	__run_thread(this, readyThread);
	235
	236	// Are we done?
	237	if( __atomic_load_n(&this->do_terminate, __ATOMIC_SEQ_CST) ) break MAIN_LOOP;
[325e6ea]	238
	239	#if !defined(__CFA_NO_STATISTICS__)
	240	unsigned long long curr = rdtscl();
	241	if(curr > (last_tally + 500000000)) {
	242	__tally_stats(this->cltr->stats, __cfaabi_tls.this_stats);
	243	last_tally = curr;
	244	}
	245	#endif
[dddb3dd0]	246
	247	if(this->io.pending && !this->io.dirty) {
	248	__cfa_io_flush( this );
	249	}
[c81ebf9]	250	}
	251
[4069faad]	252	__cfadbg_print_safe(runtime_core, "Kernel : core %p stopping\n", this);
[c84e80a]	253	}
[8118303]	254
[dddb3dd0]	255	__cfa_io_stop( this );
	256
[454f478]	257	post( this->terminated );
[bdeba0b]	258
[dddb3dd0]	259
[28d73c1]	260	if(this == mainProcessor) {
[6a490b2]	261	// HACK : the coroutine context switch expects this_thread to be set
	262	// and it make sense for it to be set in all other cases except here
	263	// fake it
[8fc652e0]	264	__cfaabi_tls.this_thread = mainThread;
[6a490b2]	265	}
[7768b8d]	266
[4069faad]	267	__cfadbg_print_safe(runtime_core, "Kernel : core %p terminated\n", this);
[c84e80a]	268	}
	269
[5c1a531]	270	static int * __volatile_errno() __attribute__((noinline));
	271	static int * __volatile_errno() { asm(""); return &errno; }
	272
[14a61b5]	273	// KERNEL ONLY
[1c273d0]	274	// runThread runs a thread by context switching
	275	// from the processor coroutine to the target thread
[ac2b598]	276	static void __run_thread(processor * this, $thread * thrd_dst) {
[8fc652e0]	277	/* paranoid */ verify( ! __preemption_enabled() );
[1eb239e4]	278	/* paranoid */ verifyf( thrd_dst->state == Ready \|\| thrd_dst->preempted != __NO_PREEMPTION, "state : %d, preempted %d\n", thrd_dst->state, thrd_dst->preempted);
	279	/* paranoid */ verifyf( thrd_dst->link.next == 0p, "Expected null got %p", thrd_dst->link.next );
	280	__builtin_prefetch( thrd_dst->context.SP );
	281
[dddb3dd0]	282	__cfadbg_print_safe(runtime_core, "Kernel : core %p running thread %p (%s)\n", this, thrd_dst, thrd_dst->self_cor.name);
	283
[ac2b598]	284	$coroutine * proc_cor = get_coroutine(this->runner);
[8fcbb4c]	285
[9f575ea]	286	// set state of processor coroutine to inactive
	287	verify(proc_cor->state == Active);
[ae7be7a]	288	proc_cor->state = Blocked;
[e8e457e]	289
[9f575ea]	290	// Actually run the thread
[3381ed7]	291	RUNNING: while(true) {
[ff79d5e]	292	thrd_dst->preempted = __NO_PREEMPTION;
	293	thrd_dst->state = Active;
[e8e457e]	294
[58d64a4]	295	// Update global state
[8fc652e0]	296	kernelTLS().this_thread = thrd_dst;
[75f3522]	297
[8fc652e0]	298	/* paranoid */ verify( ! __preemption_enabled() );
	299	/* paranoid */ verify( kernelTLS().this_thread == thrd_dst );
[9d6e1b8a]	300	/* paranoid */ verify( thrd_dst->curr_cluster == this->cltr );
[b4b63e8]	301	/* paranoid */ verify( thrd_dst->context.SP );
[5afb49a]	302	/* paranoid */ verify( thrd_dst->state != Halted );
[210b8b3]	303	/* paranoid */ verifyf( ((uintptr_t)thrd_dst->context.SP) < ((uintptr_t)__get_stack(thrd_dst->curr_cor)->base ) \|\| thrd_dst->curr_cor == proc_cor, "ERROR : Destination $thread %p has been corrupted.\n StackPointer too small.\n", thrd_dst ); // add escape condition if we are setting up the processor
	304	/* paranoid */ verifyf( ((uintptr_t)thrd_dst->context.SP) > ((uintptr_t)__get_stack(thrd_dst->curr_cor)->limit) \|\| thrd_dst->curr_cor == proc_cor, "ERROR : Destination $thread %p has been corrupted.\n StackPointer too large.\n", thrd_dst ); // add escape condition if we are setting up the processor
[ac12f1f]	305	/* paranoid */ verify( 0x0D15EA5E0D15EA5Ep == thrd_dst->canary );
[b4b63e8]	306
[3381ed7]	307
[58d64a4]	308
[9f575ea]	309	// set context switch to the thread that the processor is executing
[c7a900a]	310	__cfactx_switch( &proc_cor->context, &thrd_dst->context );
	311	// when __cfactx_switch returns we are back in the processor coroutine
[9f575ea]	312
[ac12f1f]	313	/* paranoid */ verify( 0x0D15EA5E0D15EA5Ep == thrd_dst->canary );
[210b8b3]	314	/* paranoid */ verifyf( ((uintptr_t)thrd_dst->context.SP) > ((uintptr_t)__get_stack(thrd_dst->curr_cor)->limit), "ERROR : Destination $thread %p has been corrupted.\n StackPointer too large.\n", thrd_dst );
	315	/* paranoid */ verifyf( ((uintptr_t)thrd_dst->context.SP) < ((uintptr_t)__get_stack(thrd_dst->curr_cor)->base ), "ERROR : Destination $thread %p has been corrupted.\n StackPointer too small.\n", thrd_dst );
[b4b63e8]	316	/* paranoid */ verify( thrd_dst->context.SP );
[9d6e1b8a]	317	/* paranoid */ verify( thrd_dst->curr_cluster == this->cltr );
[8fc652e0]	318	/* paranoid */ verify( kernelTLS().this_thread == thrd_dst );
	319	/* paranoid */ verify( ! __preemption_enabled() );
[75f3522]	320
[58d64a4]	321	// Reset global state
[8fc652e0]	322	kernelTLS().this_thread = 0p;
[3381ed7]	323
	324	// We just finished running a thread, there are a few things that could have happened.
	325	// 1 - Regular case : the thread has blocked and now one has scheduled it yet.
	326	// 2 - Racy case : the thread has blocked but someone has already tried to schedule it.
	327	// 4 - Preempted
	328	// In case 1, we may have won a race so we can't write to the state again.
	329	// In case 2, we lost the race so we now own the thread.
	330
	331	if(unlikely(thrd_dst->preempted != __NO_PREEMPTION)) {
	332	// The thread was preempted, reschedule it and reset the flag
[e873838]	333	__schedule_thread( thrd_dst );
[3381ed7]	334	break RUNNING;
	335	}
[75f3522]	336
[3ea8ad1]	337	if(unlikely(thrd_dst->state == Halting)) {
[ff79d5e]	338	// The thread has halted, it should never be scheduled/run again
[5afb49a]	339	// finish the thread
	340	__thread_finish( thrd_dst );
[ff79d5e]	341	break RUNNING;
	342	}
	343
	344	/* paranoid */ verify( thrd_dst->state == Active );
	345	thrd_dst->state = Blocked;
	346
[3381ed7]	347	// set state of processor coroutine to active and the thread to inactive
[ff79d5e]	348	int old_ticket = __atomic_fetch_sub(&thrd_dst->ticket, 1, __ATOMIC_SEQ_CST);
	349	switch(old_ticket) {
[6a77224]	350	case TICKET_RUNNING:
[3381ed7]	351	// This is case 1, the regular case, nothing more is needed
	352	break RUNNING;
[6a77224]	353	case TICKET_UNBLOCK:
[3381ed7]	354	// This is case 2, the racy case, someone tried to run this thread before it finished blocking
	355	// In this case, just run it again.
	356	continue RUNNING;
	357	default:
	358	// This makes no sense, something is wrong abort
[ff79d5e]	359	abort();
[3381ed7]	360	}
[9f575ea]	361	}
[e8e457e]	362
[9f575ea]	363	// Just before returning to the processor, set the processor coroutine to active
[e8e457e]	364	proc_cor->state = Active;
[1eb239e4]	365
[dddb3dd0]	366	__cfadbg_print_safe(runtime_core, "Kernel : core %p finished running thread %p\n", this, thrd_dst);
	367
[8fc652e0]	368	/* paranoid */ verify( ! __preemption_enabled() );
[82c948c]	369	}
	370
[14a61b5]	371	// KERNEL_ONLY
[b0c7419]	372	void returnToKernel() {
[8fc652e0]	373	/* paranoid */ verify( ! __preemption_enabled() );
	374	$coroutine * proc_cor = get_coroutine(kernelTLS().this_processor->runner);
	375	$thread * thrd_src = kernelTLS().this_thread;
[e8e457e]	376
[29cb302]	377	#if !defined(__CFA_NO_STATISTICS__)
[8fc652e0]	378	struct processor * last_proc = kernelTLS().this_processor;
[29cb302]	379	#endif
	380
[9f575ea]	381	// Run the thread on this processor
	382	{
	383	int local_errno = *__volatile_errno();
	384	#if defined( __i386 ) \|\| defined( __x86_64 )
	385	__x87_store;
	386	#endif
[b4b63e8]	387	/* paranoid */ verify( proc_cor->context.SP );
[ac12f1f]	388	/* paranoid */ verify( 0x0D15EA5E0D15EA5Ep == thrd_src->canary );
[c7a900a]	389	__cfactx_switch( &thrd_src->context, &proc_cor->context );
[ac12f1f]	390	/* paranoid */ verify( 0x0D15EA5E0D15EA5Ep == thrd_src->canary );
[9f575ea]	391	#if defined( __i386 ) \|\| defined( __x86_64 )
	392	__x87_load;
	393	#endif
	394	*__volatile_errno() = local_errno;
[8fcbb4c]	395	}
[deca0f5]	396
[29cb302]	397	#if !defined(__CFA_NO_STATISTICS__)
[8fc652e0]	398	if(last_proc != kernelTLS().this_processor) {
[29cb302]	399	__tls_stats()->ready.threads.migration++;
	400	}
	401	#endif
	402
[8fc652e0]	403	/* paranoid */ verify( ! __preemption_enabled() );
[210b8b3]	404	/* paranoid */ verifyf( ((uintptr_t)thrd_src->context.SP) < ((uintptr_t)__get_stack(thrd_src->curr_cor)->base ), "ERROR : Returning $thread %p has been corrupted.\n StackPointer too small.\n", thrd_src );
	405	/* paranoid */ verifyf( ((uintptr_t)thrd_src->context.SP) > ((uintptr_t)__get_stack(thrd_src->curr_cor)->limit), "ERROR : Returning $thread %p has been corrupted.\n StackPointer too large.\n", thrd_src );
[c84e80a]	406	}
	407
[8def349]	408	//-----------------------------------------------------------------------------
	409	// Scheduler routines
[14a61b5]	410	// KERNEL ONLY
[e873838]	411	void __schedule_thread( $thread * thrd ) {
[8fc652e0]	412	/* paranoid */ verify( ! __preemption_enabled() );
[9d6e1b8a]	413	/* paranoid */ verify( kernelTLS().this_proc_id );
[6a490b2]	414	/* paranoid */ verify( thrd );
	415	/* paranoid */ verify( thrd->state != Halted );
[9d6e1b8a]	416	/* paranoid */ verify( thrd->curr_cluster );
[3381ed7]	417	/* paranoid */ #if defined( __CFA_WITH_VERIFY__ )
[504a7dc]	418	/* paranoid */ if( thrd->state == Blocked \|\| thrd->state == Start ) assertf( thrd->preempted == __NO_PREEMPTION,
	419	"Error inactive thread marked as preempted, state %d, preemption %d\n", thrd->state, thrd->preempted );
[ff79d5e]	420	/* paranoid */ if( thrd->preempted != __NO_PREEMPTION ) assertf(thrd->state == Active,
[504a7dc]	421	"Error preempted thread marked as not currently running, state %d, preemption %d\n", thrd->state, thrd->preempted );
[3381ed7]	422	/* paranoid */ #endif
[6a490b2]	423	/* paranoid */ verifyf( thrd->link.next == 0p, "Expected null got %p", thrd->link.next );
[ac12f1f]	424	/* paranoid */ verify( 0x0D15EA5E0D15EA5Ep == thrd->canary );
[b4b63e8]	425
[9f575ea]	426
[ae7be7a]	427	if (thrd->preempted == __NO_PREEMPTION) thrd->state = Ready;
[6b4cdd3]	428
[e873838]	429	ready_schedule_lock();
[32a8b61]	430	// Dereference the thread now because once we push it, there is not guaranteed it's still valid.
	431	struct cluster * cl = thrd->curr_cluster;
	432
	433	// push the thread to the cluster ready-queue
	434	push( cl, thrd );
	435
	436	// variable thrd is no longer safe to use
	437
	438	// wake the cluster using the save variable.
	439	__wake_one( cl );
[e873838]	440	ready_schedule_unlock();
[1c273d0]	441
[8fc652e0]	442	/* paranoid */ verify( ! __preemption_enabled() );
[db6f06a]	443	}
	444
[14a61b5]	445	// KERNEL ONLY
[1eb239e4]	446	static inline $thread * __next_thread(cluster * this) with( *this ) {
[8fc652e0]	447	/* paranoid */ verify( ! __preemption_enabled() );
	448	/* paranoid */ verify( kernelTLS().this_proc_id );
[7768b8d]	449
[e873838]	450	ready_schedule_lock();
[1eb239e4]	451	$thread * thrd = pop( this );
[e873838]	452	ready_schedule_unlock();
[7768b8d]	453
[8fc652e0]	454	/* paranoid */ verify( kernelTLS().this_proc_id );
	455	/* paranoid */ verify( ! __preemption_enabled() );
[1eb239e4]	456	return thrd;
[eb2e723]	457	}
	458
[64a7146]	459	// KERNEL ONLY
[1eb239e4]	460	static inline $thread * __next_thread_slow(cluster * this) with( *this ) {
[8fc652e0]	461	/* paranoid */ verify( ! __preemption_enabled() );
	462	/* paranoid */ verify( kernelTLS().this_proc_id );
[64a7146]	463
[e873838]	464	ready_schedule_lock();
[1eb239e4]	465	$thread * thrd = pop_slow( this );
[e873838]	466	ready_schedule_unlock();
[64a7146]	467
[8fc652e0]	468	/* paranoid */ verify( kernelTLS().this_proc_id );
	469	/* paranoid */ verify( ! __preemption_enabled() );
[1eb239e4]	470	return thrd;
[64a7146]	471	}
	472
[e873838]	473	void unpark( $thread * thrd ) {
	474	if( !thrd ) return;
	475
[ff79d5e]	476	int old_ticket = __atomic_fetch_add(&thrd->ticket, 1, __ATOMIC_SEQ_CST);
	477	switch(old_ticket) {
[6a77224]	478	case TICKET_RUNNING:
[3381ed7]	479	// Wake won the race, the thread will reschedule/rerun itself
	480	break;
[6a77224]	481	case TICKET_BLOCKED:
[3381ed7]	482	/* paranoid */ verify( ! thrd->preempted != __NO_PREEMPTION );
[ff79d5e]	483	/* paranoid */ verify( thrd->state == Blocked );
[0b33412]	484
[8fc652e0]	485	{
	486	/* paranoid */ verify( publicTLS_get(this_proc_id) );
	487	bool full = publicTLS_get(this_proc_id)->full_proc;
	488	if(full) disable_interrupts();
	489
	490	/* paranoid */ verify( ! __preemption_enabled() );
	491
	492	// Wake lost the race,
	493	__schedule_thread( thrd );
	494
	495	/* paranoid */ verify( ! __preemption_enabled() );
	496
	497	if(full) enable_interrupts( __cfaabi_dbg_ctx );
	498	/* paranoid */ verify( publicTLS_get(this_proc_id) );
	499	}
	500
[3381ed7]	501	break;
	502	default:
	503	// This makes no sense, something is wrong abort
[7ee8153]	504	abort("Thread %p (%s) has mismatch park/unpark\n", thrd, thrd->self_cor.name);
[de6319f]	505	}
[eb2e723]	506	}
	507
[e235429]	508	void park( void ) {
[8fc652e0]	509	/* paranoid */ verify( __preemption_enabled() );
[82ff5845]	510	disable_interrupts();
[8fc652e0]	511	/* paranoid */ verify( ! __preemption_enabled() );
	512	/* paranoid */ verify( kernelTLS().this_thread->preempted == __NO_PREEMPTION );
[0b33412]	513
[82c948c]	514	returnToKernel();
[0b33412]	515
[8fc652e0]	516	/* paranoid */ verify( ! __preemption_enabled() );
[36982fc]	517	enable_interrupts( __cfaabi_dbg_ctx );
[8fc652e0]	518	/* paranoid */ verify( __preemption_enabled() );
[0c78741]	519
	520	}
[09800e9]	521
[5afb49a]	522	extern "C" {
	523	// Leave the thread monitor
	524	// last routine called by a thread.
	525	// Should never return
	526	void __cfactx_thrd_leave() {
[8fc652e0]	527	$thread * thrd = active_thread();
[5afb49a]	528	$monitor * this = &thrd->self_mon;
	529
	530	// Lock the monitor now
	531	lock( this->lock __cfaabi_dbg_ctx2 );
	532
	533	disable_interrupts();
	534
[9d6e1b8a]	535	/* paranoid */ verify( ! __preemption_enabled() );
	536	/* paranoid */ verify( thrd->state == Active );
	537	/* paranoid */ verify( 0x0D15EA5E0D15EA5Ep == thrd->canary );
	538	/* paranoid */ verify( kernelTLS().this_thread == thrd );
	539	/* paranoid */ verify( thrd->context.SP );
	540	/* paranoid */ verifyf( ((uintptr_t)thrd->context.SP) > ((uintptr_t)__get_stack(thrd->curr_cor)->limit), "ERROR : $thread %p has been corrupted.\n StackPointer too large.\n", thrd );
	541	/* paranoid */ verifyf( ((uintptr_t)thrd->context.SP) < ((uintptr_t)__get_stack(thrd->curr_cor)->base ), "ERROR : $thread %p has been corrupted.\n StackPointer too small.\n", thrd );
	542
[3ea8ad1]	543	thrd->state = Halting;
[58688bf]	544	if( TICKET_RUNNING != thrd->ticket ) { abort( "Thread terminated with pending unpark" ); }
[9d6e1b8a]	545	if( thrd != this->owner ) { abort( "Thread internal monitor has incorrect owner" ); }
	546	if( this->recursion != 1) { abort( "Thread internal monitor has unbalanced recursion" ); }
[5afb49a]	547
	548	// Leave the thread
	549	returnToKernel();
	550
	551	// Control flow should never reach here!
[9d6e1b8a]	552	abort();
[5afb49a]	553	}
[09800e9]	554	}
	555
[14a61b5]	556	// KERNEL ONLY
[3381ed7]	557	bool force_yield( __Preemption_Reason reason ) {
[8fc652e0]	558	/* paranoid */ verify( __preemption_enabled() );
[09800e9]	559	disable_interrupts();
[8fc652e0]	560	/* paranoid */ verify( ! __preemption_enabled() );
[09800e9]	561
[8fc652e0]	562	$thread * thrd = kernelTLS().this_thread;
[ff79d5e]	563	/* paranoid */ verify(thrd->state == Active);
[3381ed7]	564
	565	// SKULLDUGGERY: It is possible that we are preempting this thread just before
	566	// it was going to park itself. If that is the case and it is already using the
	567	// intrusive fields then we can't use them to preempt the thread
	568	// If that is the case, abandon the preemption.
	569	bool preempted = false;
[504a7dc]	570	if(thrd->link.next == 0p) {
[3381ed7]	571	preempted = true;
	572	thrd->preempted = reason;
	573	returnToKernel();
[de6319f]	574	}
[f2b12406]	575
[8fc652e0]	576	/* paranoid */ verify( ! __preemption_enabled() );
[3381ed7]	577	enable_interrupts_noPoll();
[8fc652e0]	578	/* paranoid */ verify( __preemption_enabled() );
[f2b12406]	579
[3381ed7]	580	return preempted;
[f2b12406]	581	}
	582
[14a61b5]	583	//=============================================================================================
[92e7631]	584	// Kernel Idle Sleep
[14a61b5]	585	//=============================================================================================
[64a7146]	586	// Wake a thread from the front if there are any
[e873838]	587	static void __wake_one(cluster * this) {
[8fc652e0]	588	/* paranoid */ verify( ! __preemption_enabled() );
[e873838]	589	/* paranoid */ verify( ready_schedule_islocked() );
[14a61b5]	590
[64a7146]	591	// Check if there is a sleeping processor
[1eb239e4]	592	processor * p;
	593	unsigned idle;
	594	unsigned total;
	595	[idle, total, p] = query(this->idles);
[14a61b5]	596
[64a7146]	597	// If no one is sleeping, we are done
[1eb239e4]	598	if( idle == 0 ) return;
[14a61b5]	599
[64a7146]	600	// We found a processor, wake it up
[dddb3dd0]	601	eventfd_t val;
	602	val = 1;
	603	eventfd_write( p->idle, val );
[14a61b5]	604
[1eb239e4]	605	#if !defined(__CFA_NO_STATISTICS__)
	606	__tls_stats()->ready.sleep.wakes++;
	607	#endif
	608
[e873838]	609	/* paranoid */ verify( ready_schedule_islocked() );
[8fc652e0]	610	/* paranoid */ verify( ! __preemption_enabled() );
[1eb239e4]	611
	612	return;
[64a7146]	613	}
[14a61b5]	614
[64a7146]	615	// Unconditionnaly wake a thread
[1eb239e4]	616	void __wake_proc(processor * this) {
[64a7146]	617	__cfadbg_print_safe(runtime_core, "Kernel : waking Processor %p\n", this);
[14a61b5]	618
[64a7146]	619	disable_interrupts();
[8fc652e0]	620	/* paranoid */ verify( ! __preemption_enabled() );
[dddb3dd0]	621	eventfd_t val;
	622	val = 1;
[55d6affb]	623	eventfd_write( this->idle, val );
[64a7146]	624	enable_interrupts( __cfaabi_dbg_ctx );
[92e7631]	625	}
	626
[1eb239e4]	627	static void push (__cluster_idles & this, processor & proc) {
[8fc652e0]	628	/* paranoid */ verify( ! __preemption_enabled() );
[1eb239e4]	629	lock( this );
	630	this.idle++;
	631	/* paranoid */ verify( this.idle <= this.total );
[8e16177]	632
[1eb239e4]	633	insert_first(this.list, proc);
	634	unlock( this );
[8fc652e0]	635	/* paranoid */ verify( ! __preemption_enabled() );
[1eb239e4]	636	}
[8e16177]	637
[1eb239e4]	638	static void remove(__cluster_idles & this, processor & proc) {
[8fc652e0]	639	/* paranoid */ verify( ! __preemption_enabled() );
[1eb239e4]	640	lock( this );
	641	this.idle--;
	642	/* paranoid */ verify( this.idle >= 0 );
[c34ebf2]	643
[1eb239e4]	644	remove(proc);
	645	unlock( this );
[8fc652e0]	646	/* paranoid */ verify( ! __preemption_enabled() );
[1eb239e4]	647	}
[c34ebf2]	648
[1eb239e4]	649	static [unsigned idle, unsigned total, * processor] query( & __cluster_idles this ) {
	650	for() {
	651	uint64_t l = __atomic_load_n(&this.lock, __ATOMIC_SEQ_CST);
	652	if( 1 == (l % 2) ) { Pause(); continue; }
	653	unsigned idle = this.idle;
	654	unsigned total = this.total;
	655	processor * proc = &this.list`first;
[7fdae38]	656	// Compiler fence is unnecessary, but gcc-8 and older incorrectly reorder code without it
	657	asm volatile("": : :"memory");
[1eb239e4]	658	if(l != __atomic_load_n(&this.lock, __ATOMIC_SEQ_CST)) { Pause(); continue; }
	659	return [idle, total, proc];
	660	}
[6b4cdd3]	661	}
	662
[dbe9b08]	663	//=============================================================================================
	664	// Unexpected Terminating logic
	665	//=============================================================================================
[92bfda0]	666	void __kernel_abort_msg( char * abort_text, int abort_text_size ) {
	667	$thread * thrd = __cfaabi_tls.this_thread;
[9d944b2]	668
[de94a60]	669	if(thrd) {
	670	int len = snprintf( abort_text, abort_text_size, "Error occurred while executing thread %.256s (%p)", thrd->self_cor.name, thrd );
[1c40091]	671	__cfaabi_bits_write( STDERR_FILENO, abort_text, len );
[de94a60]	672
[212c2187]	673	if ( &thrd->self_cor != thrd->curr_cor ) {
	674	len = snprintf( abort_text, abort_text_size, " in coroutine %.256s (%p).\n", thrd->curr_cor->name, thrd->curr_cor );
[1c40091]	675	__cfaabi_bits_write( STDERR_FILENO, abort_text, len );
[de94a60]	676	}
	677	else {
[1c40091]	678	__cfaabi_bits_write( STDERR_FILENO, ".\n", 2 );
[de94a60]	679	}
[1c273d0]	680	}
[9d944b2]	681	else {
[de94a60]	682	int len = snprintf( abort_text, abort_text_size, "Error occurred outside of any thread.\n" );
[1c40091]	683	__cfaabi_bits_write( STDERR_FILENO, abort_text, len );
[9d944b2]	684	}
	685	}
	686
[92bfda0]	687	int __kernel_abort_lastframe( void ) __attribute__ ((__nothrow__)) {
	688	return get_coroutine(__cfaabi_tls.this_thread) == get_coroutine(mainThread) ? 4 : 2;
[2b8bc41]	689	}
	690
[de94a60]	691	static __spinlock_t kernel_debug_lock;
	692
[9d944b2]	693	extern "C" {
[1c40091]	694	void __cfaabi_bits_acquire() {
[36982fc]	695	lock( kernel_debug_lock __cfaabi_dbg_ctx2 );
[9d944b2]	696	}
	697
[1c40091]	698	void __cfaabi_bits_release() {
[ea7d2b0]	699	unlock( kernel_debug_lock );
[9d944b2]	700	}
[8118303]	701	}
	702
[fa21ac9]	703	//=============================================================================================
	704	// Kernel Utilities
	705	//=============================================================================================
[dddb3dd0]	706	#if defined(CFA_HAVE_LINUX_IO_URING_H)
	707	#include "io/types.hfa"
	708	#endif
	709
	710	static inline void __maybe_io_drain( processor * proc ) {
	711	#if defined(CFA_HAVE_LINUX_IO_URING_H)
	712	__cfadbg_print_safe(runtime_core, "Kernel : core %p checking io for ring %d\n", proc, proc->io.ctx->fd);
	713
	714	// Check if we should drain the queue
	715	$io_context * ctx = proc->io.ctx;
	716	unsigned head = *ctx->cq.head;
	717	unsigned tail = *ctx->cq.tail;
	718	if(head != tail) __cfa_io_drain( proc );
	719	#endif
	720	}
	721
[de94a60]	722	//-----------------------------------------------------------------------------
	723	// Debug
	724	__cfaabi_dbg_debug_do(
[1997b4e]	725	extern "C" {
[ae66348]	726	void __cfaabi_dbg_record_lock(__spinlock_t & this, const char prev_name[]) {
[1997b4e]	727	this.prev_name = prev_name;
[8fc652e0]	728	this.prev_thrd = kernelTLS().this_thread;
[1997b4e]	729	}
[9181f1d]	730	}
[f7d6bb0]	731	)
[2026bb6]	732
	733	//-----------------------------------------------------------------------------
	734	// Debug
[8c50aed]	735	bool threading_enabled(void) __attribute__((const)) {
[2026bb6]	736	return true;
	737	}
[c34ebf2]	738
	739	//-----------------------------------------------------------------------------
	740	// Statistics
	741	#if !defined(__CFA_NO_STATISTICS__)
	742	void print_halts( processor & this ) {
	743	this.print_halts = true;
	744	}
[58688bf]	745
	746	void print_stats_now( cluster & this, int flags ) {
[1b033b8]	747	__print_stats( this.stats, this.print_stats, "Cluster", this.name, (void*)&this );
	748	}
	749
	750	extern int __print_alarm_stats;
	751	void print_alarm_stats() {
	752	__print_alarm_stats = -1;
[58688bf]	753	}
[c34ebf2]	754	#endif
[8118303]	755	// Local Variables: //
	756	// mode: c //
	757	// tab-width: 4 //
	758	// End: //

Note: See TracBrowser for help on using the repository browser.

Download in other formats:

Original Format