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setup.cfa@ 150d21a

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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 150d21a was 4c4d854, checked in by Thierry Delisle <tdelisle@…>, 5 years ago
Fixed broken initialization and add verify.
Property mode set to `100644`
File size: 15.7 KB

Rev	Line
[3e2b9c9]	1	//
	2	// Cforall Version 1.0.0 Copyright (C) 2020 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	// io/setup.cfa --
	8	//
	9	// Author : Thierry Delisle
	10	// Created On : Fri Jul 31 16:25:51 2020
	11	// Last Modified By :
	12	// Last Modified On :
	13	// Update Count :
	14	//
	15
	16	#define __cforall_thread__
	17	#define _GNU_SOURCE /* See feature_test_macros(7) */
	18
[80444bb]	19	#if defined(__CFA_DEBUG__)
	20	// #define __CFA_DEBUG_PRINT_IO__
	21	// #define __CFA_DEBUG_PRINT_IO_CORE__
	22	#endif
	23
[3e2b9c9]	24	#include "io/types.hfa"
[c44d652]	25	#include "kernel.hfa"
[3e2b9c9]	26
	27	#if !defined(CFA_HAVE_LINUX_IO_URING_H)
	28	void __kernel_io_startup() {
	29	// Nothing to do without io_uring
	30	}
	31
	32	void __kernel_io_shutdown() {
	33	// Nothing to do without io_uring
	34	}
	35
[f277633e]	36	void ?{}(io_context_params & this) {}
	37
[78da4ab]	38	void ?{}($io_context & this, struct cluster & cl) {}
	39	void ^?{}($io_context & this) {}
[3e2b9c9]	40
[78da4ab]	41	$io_arbiter * create(void) { return 0p; }
	42	void destroy($io_arbiter *) {}
[b7664a03]	43
[3e2b9c9]	44	#else
	45	#include <errno.h>
	46	#include <stdint.h>
	47	#include <string.h>
	48	#include <signal.h>
	49	#include <unistd.h>
	50
	51	extern "C" {
	52	#include <pthread.h>
	53	#include <sys/epoll.h>
[426f60c]	54	#include <sys/eventfd.h>
[3e2b9c9]	55	#include <sys/mman.h>
	56	#include <sys/syscall.h>
	57
	58	#include <linux/io_uring.h>
	59	}
	60
	61	#include "bitmanip.hfa"
	62	#include "kernel_private.hfa"
	63	#include "thread.hfa"
	64
	65	void ?{}(io_context_params & this) {
	66	this.num_entries = 256;
	67	}
	68
	69	static void * __io_poller_slow( void * arg );
	70
	71	// Weirdly, some systems that do support io_uring don't actually define these
	72	#ifdef __alpha__
	73	/*
	74	* alpha is the only exception, all other architectures
	75	* have common numbers for new system calls.
	76	*/
	77	#ifndef __NR_io_uring_setup
	78	#define __NR_io_uring_setup 535
	79	#endif
	80	#ifndef __NR_io_uring_enter
	81	#define __NR_io_uring_enter 536
	82	#endif
	83	#ifndef __NR_io_uring_register
	84	#define __NR_io_uring_register 537
	85	#endif
	86	#else /* !__alpha__ */
	87	#ifndef __NR_io_uring_setup
	88	#define __NR_io_uring_setup 425
	89	#endif
	90	#ifndef __NR_io_uring_enter
	91	#define __NR_io_uring_enter 426
	92	#endif
	93	#ifndef __NR_io_uring_register
	94	#define __NR_io_uring_register 427
	95	#endif
	96	#endif
	97
	98	//=============================================================================================
	99	// I/O Startup / Shutdown logic + Master Poller
	100	//=============================================================================================
	101
	102	// IO Master poller loop forward
	103	static void * iopoll_loop( __attribute__((unused)) void * args );
	104
	105	static struct {
[4fc3343]	106	pthread_t thrd; // pthread handle to io poller thread
	107	void * stack; // pthread stack for io poller thread
	108	int epollfd; // file descriptor to the epoll instance
	109	volatile bool run; // Whether or not to continue
	110	volatile bool stopped; // Whether the poller has finished running
	111	volatile uint64_t epoch; // Epoch used for memory reclamation
[3e2b9c9]	112	} iopoll;
	113
	114	void __kernel_io_startup(void) {
[80444bb]	115	__cfadbg_print_safe(io_core, "Kernel : Creating EPOLL instance\n" );
[3e2b9c9]	116
	117	iopoll.epollfd = epoll_create1(0);
	118	if (iopoll.epollfd == -1) {
	119	abort( "internal error, epoll_create1\n");
	120	}
	121
[80444bb]	122	__cfadbg_print_safe(io_core, "Kernel : Starting io poller thread\n" );
[3e2b9c9]	123
[4fc3343]	124	iopoll.stack = __create_pthread( &iopoll.thrd, iopoll_loop, 0p );
	125	iopoll.run = true;
	126	iopoll.stopped = false;
	127	iopoll.epoch = 0;
[3e2b9c9]	128	}
	129
	130	void __kernel_io_shutdown(void) {
	131	// Notify the io poller thread of the shutdown
	132	iopoll.run = false;
	133	sigval val = { 1 };
	134	pthread_sigqueue( iopoll.thrd, SIGUSR1, val );
	135
	136	// Wait for the io poller thread to finish
	137
[bfcf6b9]	138	__destroy_pthread( iopoll.thrd, iopoll.stack, 0p );
[3e2b9c9]	139
	140	int ret = close(iopoll.epollfd);
	141	if (ret == -1) {
	142	abort( "internal error, close epoll\n");
	143	}
	144
	145	// Io polling is now fully stopped
	146
[80444bb]	147	__cfadbg_print_safe(io_core, "Kernel : IO poller stopped\n" );
[3e2b9c9]	148	}
	149
	150	static void * iopoll_loop( __attribute__((unused)) void * args ) {
	151	__processor_id_t id;
[58d64a4]	152	id.full_proc = false;
[3e2b9c9]	153	id.id = doregister(&id);
[8fc652e0]	154	__cfaabi_tls.this_proc_id = &id;
[80444bb]	155	__cfadbg_print_safe(io_core, "Kernel : IO poller thread starting\n" );
[3e2b9c9]	156
	157	// Block signals to control when they arrive
	158	sigset_t mask;
	159	sigfillset(&mask);
	160	if ( pthread_sigmask( SIG_BLOCK, &mask, 0p ) == -1 ) {
	161	abort( "internal error, pthread_sigmask" );
	162	}
	163
	164	sigdelset( &mask, SIGUSR1 );
	165
	166	// Create sufficient events
	167	struct epoll_event events[10];
	168	// Main loop
	169	while( iopoll.run ) {
[ece0e80]	170	__cfadbg_print_safe(io_core, "Kernel I/O - epoll : waiting on io_uring contexts\n");
	171
[d611995]	172	// increment the epoch to notify any deleters we are starting a new cycle
	173	__atomic_fetch_add(&iopoll.epoch, 1, __ATOMIC_SEQ_CST);
	174
[3e2b9c9]	175	// Wait for events
	176	int nfds = epoll_pwait( iopoll.epollfd, events, 10, -1, &mask );
	177
[ece0e80]	178	__cfadbg_print_safe(io_core, "Kernel I/O - epoll : %d io contexts events, waking up\n", nfds);
	179
[3e2b9c9]	180	// Check if an error occured
	181	if (nfds == -1) {
	182	if( errno == EINTR ) continue;
	183	abort( "internal error, pthread_sigmask" );
	184	}
	185
	186	for(i; nfds) {
[78da4ab]	187	$io_context * io_ctx = ($io_context *)(uintptr_t)events[i].data.u64;
[3e2b9c9]	188	/* paranoid */ verify( io_ctx );
[78da4ab]	189	__cfadbg_print_safe(io_core, "Kernel I/O - epoll : Unparking io poller %d (%p)\n", io_ctx->fd, io_ctx);
[3e2b9c9]	190	#if !defined( __CFA_NO_STATISTICS__ )
[8fc652e0]	191	__cfaabi_tls.this_stats = io_ctx->self.curr_cluster->stats;
[3e2b9c9]	192	#endif
[d48b174]	193
	194	eventfd_t v;
[78da4ab]	195	eventfd_read(io_ctx->efd, &v);
[d48b174]	196
[e873838]	197	post( io_ctx->sem );
[3e2b9c9]	198	}
	199	}
	200
[4fc3343]	201	__atomic_store_n(&iopoll.stopped, true, __ATOMIC_SEQ_CST);
	202
[80444bb]	203	__cfadbg_print_safe(io_core, "Kernel : IO poller thread stopping\n" );
[3e2b9c9]	204	unregister(&id);
	205	return 0p;
	206	}
	207
	208	//=============================================================================================
	209	// I/O Context Constrution/Destruction
	210	//=============================================================================================
	211
[78da4ab]	212	static void __io_uring_setup ( $io_context & this, const io_context_params & params_in );
	213	static void __io_uring_teardown( $io_context & this );
	214	static void __epoll_register($io_context & ctx);
	215	static void __epoll_unregister($io_context & ctx);
	216	void __ioarbiter_register( $io_arbiter & mutex, $io_context & ctx );
	217	void __ioarbiter_unregister( $io_arbiter & mutex, $io_context & ctx );
[3e2b9c9]	218
[78da4ab]	219	void ?{}($io_context & this, struct cluster & cl) {
	220	(this.self){ "IO Poller", cl };
	221	this.ext_sq.empty = true;
[4c4d854]	222	this.revoked = true;
[78da4ab]	223	__io_uring_setup( this, cl.io.params );
	224	__cfadbg_print_safe(io_core, "Kernel I/O : Created ring for io_context %u (%p)\n", this.fd, &this);
[3e2b9c9]	225
[78da4ab]	226	__epoll_register(this);
[3e2b9c9]	227
[78da4ab]	228	__ioarbiter_register(*cl.io.arbiter, this);
[3e2b9c9]	229
[78da4ab]	230	__thrd_start( this, main );
	231	__cfadbg_print_safe(io_core, "Kernel I/O : Started poller thread for io_context %u\n", this.fd);
[3e2b9c9]	232	}
	233
[78da4ab]	234	void ^?{}($io_context & mutex this) {
	235	__cfadbg_print_safe(io_core, "Kernel I/O : tearing down io_context %u\n", this.fd);
[3e2b9c9]	236
[78da4ab]	237	^(this.self){};
	238	__cfadbg_print_safe(io_core, "Kernel I/O : Stopped poller thread for io_context %u\n", this.fd);
[ece0e80]	239
[78da4ab]	240	__ioarbiter_unregister(*this.arbiter, this);
[3e2b9c9]	241
[78da4ab]	242	__epoll_unregister(this);
[3e2b9c9]	243
[78da4ab]	244	__io_uring_teardown( this );
	245	__cfadbg_print_safe(io_core, "Kernel I/O : Destroyed ring for io_context %u\n", this.fd);
	246	}
[3e2b9c9]	247
[78da4ab]	248	void ?{}(io_context & this, struct cluster & cl) {
	249	// this.ctx = new(cl);
	250	this.ctx = alloc();
	251	(*this.ctx){ cl };
	252
	253	__cfadbg_print_safe(io_core, "Kernel I/O : io_context %u ready\n", this.ctx->fd);
[3e2b9c9]	254	}
	255
	256	void ^?{}(io_context & this) {
[78da4ab]	257	post( this.ctx->sem );
	258
	259	delete(this.ctx);
[3e2b9c9]	260	}
	261
[7222630]	262	extern void __disable_interrupts_hard();
	263	extern void __enable_interrupts_hard();
[bb58825]	264
[78da4ab]	265	static void __io_uring_setup( $io_context & this, const io_context_params & params_in ) {
[3e2b9c9]	266	// Step 1 : call to setup
	267	struct io_uring_params params;
	268	memset(&params, 0, sizeof(params));
[78da4ab]	269	// if( params_in.poll_submit ) params.flags \|= IORING_SETUP_SQPOLL;
	270	// if( params_in.poll_complete ) params.flags \|= IORING_SETUP_IOPOLL;
[3e2b9c9]	271
[4998155]	272	__u32 nentries = params_in.num_entries != 0 ? params_in.num_entries : 256;
[63fe427c]	273	if( !is_pow2(nentries) ) {
	274	abort("ERROR: I/O setup 'num_entries' must be a power of 2\n");
	275	}
[3e2b9c9]	276
	277	int fd = syscall(__NR_io_uring_setup, nentries, &params );
	278	if(fd < 0) {
	279	abort("KERNEL ERROR: IO_URING SETUP - %s\n", strerror(errno));
	280	}
	281
	282	// Step 2 : mmap result
[78da4ab]	283	struct __sub_ring_t & sq = this.sq;
	284	struct __cmp_ring_t & cq = this.cq;
[3e2b9c9]	285
	286	// calculate the right ring size
	287	sq.ring_sz = params.sq_off.array + (params.sq_entries * sizeof(unsigned) );
	288	cq.ring_sz = params.cq_off.cqes + (params.cq_entries * sizeof(struct io_uring_cqe));
	289
	290	// Requires features
	291	#if defined(IORING_FEAT_SINGLE_MMAP)
	292	// adjust the size according to the parameters
	293	if ((params.features & IORING_FEAT_SINGLE_MMAP) != 0) {
	294	cq.ring_sz = sq.ring_sz = max(cq.ring_sz, sq.ring_sz);
	295	}
	296	#endif
	297
	298	// mmap the Submit Queue into existence
	299	sq.ring_ptr = mmap(0, sq.ring_sz, PROT_READ \| PROT_WRITE, MAP_SHARED \| MAP_POPULATE, fd, IORING_OFF_SQ_RING);
	300	if (sq.ring_ptr == (void*)MAP_FAILED) {
	301	abort("KERNEL ERROR: IO_URING MMAP1 - %s\n", strerror(errno));
	302	}
	303
	304	// Requires features
	305	#if defined(IORING_FEAT_SINGLE_MMAP)
	306	// mmap the Completion Queue into existence (may or may not be needed)
	307	if ((params.features & IORING_FEAT_SINGLE_MMAP) != 0) {
	308	cq.ring_ptr = sq.ring_ptr;
	309	}
	310	else
	311	#endif
	312	{
	313	// We need multiple call to MMAP
	314	cq.ring_ptr = mmap(0, cq.ring_sz, PROT_READ \| PROT_WRITE, MAP_SHARED \| MAP_POPULATE, fd, IORING_OFF_CQ_RING);
	315	if (cq.ring_ptr == (void*)MAP_FAILED) {
	316	munmap(sq.ring_ptr, sq.ring_sz);
	317	abort("KERNEL ERROR: IO_URING MMAP2 - %s\n", strerror(errno));
	318	}
	319	}
	320
	321	// mmap the submit queue entries
	322	size_t size = params.sq_entries * sizeof(struct io_uring_sqe);
	323	sq.sqes = (struct io_uring_sqe *)mmap(0, size, PROT_READ \| PROT_WRITE, MAP_SHARED \| MAP_POPULATE, fd, IORING_OFF_SQES);
	324	if (sq.sqes == (struct io_uring_sqe *)MAP_FAILED) {
	325	munmap(sq.ring_ptr, sq.ring_sz);
	326	if (cq.ring_ptr != sq.ring_ptr) munmap(cq.ring_ptr, cq.ring_sz);
	327	abort("KERNEL ERROR: IO_URING MMAP3 - %s\n", strerror(errno));
	328	}
	329
[426f60c]	330	// Step 3 : Initialize the data structure
[3e2b9c9]	331	// Get the pointers from the kernel to fill the structure
	332	// submit queue
[78da4ab]	333	sq.kring.head = (volatile __u32 *)(((intptr_t)sq.ring_ptr) + params.sq_off.head);
	334	sq.kring.tail = (volatile __u32 *)(((intptr_t)sq.ring_ptr) + params.sq_off.tail);
	335	sq.kring.array = ( __u32 *)(((intptr_t)sq.ring_ptr) + params.sq_off.array);
	336	sq.mask = ( const __u32 *)(((intptr_t)sq.ring_ptr) + params.sq_off.ring_mask);
	337	sq.num = ( const __u32 *)(((intptr_t)sq.ring_ptr) + params.sq_off.ring_entries);
	338	sq.flags = ( __u32 *)(((intptr_t)sq.ring_ptr) + params.sq_off.flags);
	339	sq.dropped = ( __u32 *)(((intptr_t)sq.ring_ptr) + params.sq_off.dropped);
	340
	341	sq.kring.ready = 0;
	342	sq.kring.released = 0;
	343
	344	sq.free_ring.head = 0;
	345	sq.free_ring.tail = *sq.num;
	346	sq.free_ring.array = alloc( *sq.num, 128`align );
	347	for(i; (__u32)*sq.num) {
	348	sq.free_ring.array[i] = i;
[3e2b9c9]	349	}
	350
[78da4ab]	351	sq.to_submit = 0;
[3e2b9c9]	352
	353	// completion queue
[4998155]	354	cq.head = (volatile __u32 *)(((intptr_t)cq.ring_ptr) + params.cq_off.head);
	355	cq.tail = (volatile __u32 *)(((intptr_t)cq.ring_ptr) + params.cq_off.tail);
	356	cq.mask = ( const __u32 *)(((intptr_t)cq.ring_ptr) + params.cq_off.ring_mask);
	357	cq.num = ( const __u32 *)(((intptr_t)cq.ring_ptr) + params.cq_off.ring_entries);
	358	cq.overflow = ( __u32 *)(((intptr_t)cq.ring_ptr) + params.cq_off.overflow);
	359	cq.cqes = (struct io_uring_cqe *)(((intptr_t)cq.ring_ptr) + params.cq_off.cqes);
[3e2b9c9]	360
[426f60c]	361	// Step 4 : eventfd
[bb58825]	362	// io_uring_register is so f*cking slow on some machine that it
	363	// will never succeed if preemption isn't hard blocked
[7222630]	364	__disable_interrupts_hard();
[bb58825]	365
	366	int efd = eventfd(0, 0);
	367	if (efd < 0) {
	368	abort("KERNEL ERROR: IO_URING EVENTFD - %s\n", strerror(errno));
[426f60c]	369	}
	370
[bb58825]	371	int ret = syscall( __NR_io_uring_register, fd, IORING_REGISTER_EVENTFD, &efd, 1);
	372	if (ret < 0) {
	373	abort("KERNEL ERROR: IO_URING EVENTFD REGISTER - %s\n", strerror(errno));
[426f60c]	374	}
	375
[7222630]	376	__enable_interrupts_hard();
[bb58825]	377
[3e2b9c9]	378	// some paranoid checks
	379	/* paranoid / verifyf( (cq.mask) == ((cq.num) - 1ul32), "IO_URING Expected mask to be %u (%u entries), was %u", (cq.num) - 1ul32, cq.num, cq.mask );
	380	/* paranoid / verifyf( (cq.num) >= nentries, "IO_URING Expected %u entries, got %u", nentries, *cq.num );
	381	/* paranoid / verifyf( (cq.head) == 0, "IO_URING Expected head to be 0, got %u", *cq.head );
	382	/* paranoid / verifyf( (cq.tail) == 0, "IO_URING Expected tail to be 0, got %u", *cq.tail );
	383
	384	/* paranoid / verifyf( (sq.mask) == ((sq.num) - 1ul32), "IO_URING Expected mask to be %u (%u entries), was %u", (sq.num) - 1ul32, sq.num, sq.mask );
	385	/* paranoid / verifyf( (sq.num) >= nentries, "IO_URING Expected %u entries, got %u", nentries, *sq.num );
[78da4ab]	386	/* paranoid / verifyf( (sq.kring.head) == 0, "IO_URING Expected head to be 0, got %u", *sq.kring.head );
	387	/* paranoid / verifyf( (sq.kring.tail) == 0, "IO_URING Expected tail to be 0, got %u", *sq.kring.tail );
[3e2b9c9]	388
	389	// Update the global ring info
[78da4ab]	390	this.ring_flags = 0;
[3e2b9c9]	391	this.fd = fd;
[426f60c]	392	this.efd = efd;
[3e2b9c9]	393	}
	394
[78da4ab]	395	static void __io_uring_teardown( $io_context & this ) {
[3e2b9c9]	396	// Shutdown the io rings
[78da4ab]	397	struct __sub_ring_t & sq = this.sq;
	398	struct __cmp_ring_t & cq = this.cq;
[3e2b9c9]	399
	400	// unmap the submit queue entries
	401	munmap(sq.sqes, (sq.num) sizeof(struct io_uring_sqe));
	402
	403	// unmap the Submit Queue ring
	404	munmap(sq.ring_ptr, sq.ring_sz);
	405
	406	// unmap the Completion Queue ring, if it is different
	407	if (cq.ring_ptr != sq.ring_ptr) {
	408	munmap(cq.ring_ptr, cq.ring_sz);
	409	}
	410
	411	// close the file descriptor
	412	close(this.fd);
[426f60c]	413	close(this.efd);
[3e2b9c9]	414
[78da4ab]	415	free( this.sq.free_ring.array ); // Maybe null, doesn't matter
[3e2b9c9]	416	}
	417
	418	//=============================================================================================
	419	// I/O Context Sleep
	420	//=============================================================================================
[78da4ab]	421	static inline void __epoll_ctl($io_context & ctx, int op, const char * error) {
[d48b174]	422	struct epoll_event ev;
[d611995]	423	ev.events = EPOLLIN \| EPOLLONESHOT;
[4998155]	424	ev.data.u64 = (__u64)&ctx;
[78da4ab]	425	int ret = epoll_ctl(iopoll.epollfd, op, ctx.efd, &ev);
[3e2b9c9]	426	if (ret < 0) {
[d48b174]	427	abort( "KERNEL ERROR: EPOLL %s - (%d) %s\n", error, (int)errno, strerror(errno) );
[3e2b9c9]	428	}
	429	}
	430
[78da4ab]	431	static void __epoll_register($io_context & ctx) {
	432	__epoll_ctl(ctx, EPOLL_CTL_ADD, "ADD");
[3e2b9c9]	433	}
	434
[78da4ab]	435	static void __epoll_unregister($io_context & ctx) {
[d611995]	436	// Read the current epoch so we know when to stop
	437	size_t curr = __atomic_load_n(&iopoll.epoch, __ATOMIC_SEQ_CST);
	438
	439	// Remove the fd from the iopoller
[78da4ab]	440	__epoll_ctl(ctx, EPOLL_CTL_DEL, "REMOVE");
[d611995]	441
	442	// Notify the io poller thread of the shutdown
	443	iopoll.run = false;
	444	sigval val = { 1 };
	445	pthread_sigqueue( iopoll.thrd, SIGUSR1, val );
	446
	447	// Make sure all this is done
	448	__atomic_thread_fence(__ATOMIC_SEQ_CST);
	449
	450	// Wait for the next epoch
[4fc3343]	451	while(curr == iopoll.epoch && !iopoll.stopped) Pause();
[d611995]	452	}
	453
[78da4ab]	454	void __ioctx_prepare_block($io_context & ctx) {
	455	__cfadbg_print_safe(io_core, "Kernel I/O - epoll : Re-arming io poller %d (%p)\n", ctx.fd, &ctx);
	456	__epoll_ctl(ctx, EPOLL_CTL_MOD, "REARM");
	457	}
	458
	459
[3e2b9c9]	460	//=============================================================================================
	461	// I/O Context Misc Setup
	462	//=============================================================================================
[78da4ab]	463	void ?{}( $io_arbiter & this ) {
	464	this.pending.flag = false;
	465	}
[3e2b9c9]	466
[78da4ab]	467	void ^?{}( $io_arbiter & mutex this ) {
	468	/* paranoid */ verify( empty(this.assigned) );
	469	/* paranoid */ verify( empty(this.available) );
	470	/* paranoid */ verify( is_empty(this.pending.blocked) );
[3e2b9c9]	471	}
	472
[78da4ab]	473	$io_arbiter * create(void) {
	474	return new();
[3e2b9c9]	475	}
[78da4ab]	476	void destroy($io_arbiter * arbiter) {
	477	delete(arbiter);
	478	}
	479
	480	//=============================================================================================
	481	// I/O Context Misc Setup
	482	//=============================================================================================
	483
[c44d652]	484	#endif

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