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setup.cfa@ 108f98b2

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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 108f98b2 was ece0e80, checked in by Thierry Delisle <tdelisle@…>, 5 years ago
Added prints. Naive implementation of cancel. Server now shutdown cleanly.
Property mode set to `100644`
File size: 17.0 KB

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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
19	#if defined(__CFA_DEBUG__)
20	// #define __CFA_DEBUG_PRINT_IO__
21	// #define __CFA_DEBUG_PRINT_IO_CORE__
22	#endif
23
24	#include "io/types.hfa"
25	#include "kernel.hfa"
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
36	void ?{}(io_context_params & this) {}
37
38	void ?{}(io_context & this, struct cluster & cl) {}
39	void ?{}(io_context & this, struct cluster & cl, const io_context_params & params) {}
40
41	void ^?{}(io_context & this) {}
42	void ^?{}(io_context & this, bool cluster_context) {}
43
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>
54	#include <sys/mman.h>
55	#include <sys/syscall.h>
56
57	#include <linux/io_uring.h>
58	}
59
60	#include "bitmanip.hfa"
61	#include "kernel_private.hfa"
62	#include "thread.hfa"
63
64	void ?{}(io_context_params & this) {
65	this.num_entries = 256;
66	this.num_ready = 256;
67	this.submit_aff = -1;
68	this.eager_submits = false;
69	this.poller_submits = false;
70	this.poll_submit = false;
71	this.poll_complete = false;
72	}
73
74	static void * __io_poller_slow( void * arg );
75
76	// Weirdly, some systems that do support io_uring don't actually define these
77	#ifdef __alpha__
78	/*
79	* alpha is the only exception, all other architectures
80	* have common numbers for new system calls.
81	*/
82	#ifndef __NR_io_uring_setup
83	#define __NR_io_uring_setup 535
84	#endif
85	#ifndef __NR_io_uring_enter
86	#define __NR_io_uring_enter 536
87	#endif
88	#ifndef __NR_io_uring_register
89	#define __NR_io_uring_register 537
90	#endif
91	#else /* !__alpha__ */
92	#ifndef __NR_io_uring_setup
93	#define __NR_io_uring_setup 425
94	#endif
95	#ifndef __NR_io_uring_enter
96	#define __NR_io_uring_enter 426
97	#endif
98	#ifndef __NR_io_uring_register
99	#define __NR_io_uring_register 427
100	#endif
101	#endif
102
103	//=============================================================================================
104	// I/O Startup / Shutdown logic + Master Poller
105	//=============================================================================================
106
107	// IO Master poller loop forward
108	static void * iopoll_loop( __attribute__((unused)) void * args );
109
110	static struct {
111	pthread_t thrd; // pthread handle to io poller thread
112	void * stack; // pthread stack for io poller thread
113	int epollfd; // file descriptor to the epoll instance
114	volatile bool run; // Whether or not to continue
115	} iopoll;
116
117	void __kernel_io_startup(void) {
118	__cfadbg_print_safe(io_core, "Kernel : Creating EPOLL instance\n" );
119
120	iopoll.epollfd = epoll_create1(0);
121	if (iopoll.epollfd == -1) {
122	abort( "internal error, epoll_create1\n");
123	}
124
125	__cfadbg_print_safe(io_core, "Kernel : Starting io poller thread\n" );
126
127	iopoll.run = true;
128	iopoll.stack = __create_pthread( &iopoll.thrd, iopoll_loop, 0p );
129	}
130
131	void __kernel_io_shutdown(void) {
132	// Notify the io poller thread of the shutdown
133	iopoll.run = false;
134	sigval val = { 1 };
135	pthread_sigqueue( iopoll.thrd, SIGUSR1, val );
136
137	// Wait for the io poller thread to finish
138
139	__destroy_pthread( iopoll.thrd, iopoll.stack, 0p );
140
141	int ret = close(iopoll.epollfd);
142	if (ret == -1) {
143	abort( "internal error, close epoll\n");
144	}
145
146	// Io polling is now fully stopped
147
148	__cfadbg_print_safe(io_core, "Kernel : IO poller stopped\n" );
149	}
150
151	static void * iopoll_loop( __attribute__((unused)) void * args ) {
152	__processor_id_t id;
153	id.full_proc = false;
154	id.id = doregister(&id);
155	__cfaabi_tls.this_proc_id = &id;
156	__cfadbg_print_safe(io_core, "Kernel : IO poller thread starting\n" );
157
158	// Block signals to control when they arrive
159	sigset_t mask;
160	sigfillset(&mask);
161	if ( pthread_sigmask( SIG_BLOCK, &mask, 0p ) == -1 ) {
162	abort( "internal error, pthread_sigmask" );
163	}
164
165	sigdelset( &mask, SIGUSR1 );
166
167	// Create sufficient events
168	struct epoll_event events[10];
169	// Main loop
170	while( iopoll.run ) {
171	__cfadbg_print_safe(io_core, "Kernel I/O - epoll : waiting on io_uring contexts\n");
172
173	// Wait for events
174	int nfds = epoll_pwait( iopoll.epollfd, events, 10, -1, &mask );
175
176	__cfadbg_print_safe(io_core, "Kernel I/O - epoll : %d io contexts events, waking up\n", nfds);
177
178	// Check if an error occured
179	if (nfds == -1) {
180	if( errno == EINTR ) continue;
181	abort( "internal error, pthread_sigmask" );
182	}
183
184	for(i; nfds) {
185	$io_ctx_thread * io_ctx = ($io_ctx_thread *)(uintptr_t)events[i].data.u64;
186	/* paranoid */ verify( io_ctx );
187	__cfadbg_print_safe(io_core, "Kernel I/O - epoll : Unparking io poller %p\n", io_ctx);
188	#if !defined( __CFA_NO_STATISTICS__ )
189	__cfaabi_tls.this_stats = io_ctx->self.curr_cluster->stats;
190	#endif
191	post( io_ctx->sem );
192	}
193	}
194
195	__cfadbg_print_safe(io_core, "Kernel : IO poller thread stopping\n" );
196	unregister(&id);
197	return 0p;
198	}
199
200	//=============================================================================================
201	// I/O Context Constrution/Destruction
202	//=============================================================================================
203
204	void ?{}($io_ctx_thread & this, struct cluster & cl) { (this.self){ "IO Poller", cl }; }
205	void main( $io_ctx_thread & this );
206	static inline $thread * get_thread( $io_ctx_thread & this ) { return &this.self; }
207	void ^?{}( $io_ctx_thread & mutex this ) {}
208
209	static void __io_create ( __io_data & this, const io_context_params & params_in );
210	static void __io_destroy( __io_data & this );
211
212	void ?{}(io_context & this, struct cluster & cl, const io_context_params & params) {
213	(this.thrd){ cl };
214	this.thrd.ring = malloc();
215	__cfadbg_print_safe(io_core, "Kernel I/O : Creating ring for io_context %p\n", &this);
216	__io_create( *this.thrd.ring, params );
217
218	__cfadbg_print_safe(io_core, "Kernel I/O : Starting poller thread for io_context %p\n", &this);
219	this.thrd.done = false;
220	__thrd_start( this.thrd, main );
221
222	__cfadbg_print_safe(io_core, "Kernel I/O : io_context %p ready\n", &this);
223	}
224
225	void ?{}(io_context & this, struct cluster & cl) {
226	io_context_params params;
227	(this){ cl, params };
228	}
229
230	void ^?{}(io_context & this, bool cluster_context) {
231	__cfadbg_print_safe(io_core, "Kernel I/O : tearing down io_context %p\n", &this);
232
233	// Notify the thread of the shutdown
234	__atomic_store_n(&this.thrd.done, true, __ATOMIC_SEQ_CST);
235
236	// If this is an io_context within a cluster, things get trickier
237	$thread & thrd = this.thrd.self;
238	if( cluster_context ) {
239	// We are about to do weird things with the threads
240	// we don't need interrupts to complicate everything
241	disable_interrupts();
242
243	// Get cluster info
244	cluster & cltr = *thrd.curr_cluster;
245	/* paranoid */ verify( cltr.idles.total == 0 \|\| &cltr == mainCluster );
246	/* paranoid */ verify( !ready_mutate_islocked() );
247
248	// We need to adjust the clean-up based on where the thread is
249	if( thrd.state == Ready \|\| thrd.preempted != __NO_PREEMPTION ) {
250	// This is the tricky case
251	// The thread was preempted or ready to run and now it is on the ready queue
252	// but the cluster is shutting down, so there aren't any processors to run the ready queue
253	// the solution is to steal the thread from the ready-queue and pretend it was blocked all along
254
255	ready_schedule_lock();
256	// The thread should on the list
257	/* paranoid */ verify( thrd.link.next != 0p );
258
259	// Remove the thread from the ready queue of this cluster
260	// The thread should be the last on the list
261	__attribute__((unused)) bool removed = remove_head( &cltr, &thrd );
262	/* paranoid */ verify( removed );
263	thrd.link.next = 0p;
264	thrd.link.prev = 0p;
265
266	// Fixup the thread state
267	thrd.state = Blocked;
268	thrd.ticket = TICKET_BLOCKED;
269	thrd.preempted = __NO_PREEMPTION;
270
271	ready_schedule_unlock();
272
273	// Pretend like the thread was blocked all along
274	}
275	// !!! This is not an else if !!!
276	// Ok, now the thread is blocked (whether we cheated to get here or not)
277	if( thrd.state == Blocked ) {
278	// This is the "easy case"
279	// The thread is parked and can easily be moved to active cluster
280	verify( thrd.curr_cluster != active_cluster() \|\| thrd.curr_cluster == mainCluster );
281	thrd.curr_cluster = active_cluster();
282
283	// unpark the fast io_poller
284	unpark( &thrd );
285	}
286	else {
287	// The thread is in a weird state
288	// I don't know what to do here
289	abort("io_context poller thread is in unexpected state, cannot clean-up correctly\n");
290	}
291
292	// The weird thread kidnapping stuff is over, restore interrupts.
293	enable_interrupts( __cfaabi_dbg_ctx );
294	} else {
295	post( this.thrd.sem );
296	}
297
298	^(this.thrd){};
299	__cfadbg_print_safe(io_core, "Kernel I/O : Stopped poller thread for io_context %p\n", &this);
300
301	__io_destroy( *this.thrd.ring );
302	__cfadbg_print_safe(io_core, "Kernel I/O : Destroyed ring for io_context %p\n", &this);
303
304	free(this.thrd.ring);
305	}
306
307	void ^?{}(io_context & this) {
308	^(this){ false };
309	}
310
311	static void __io_create( __io_data & this, const io_context_params & params_in ) {
312	// Step 1 : call to setup
313	struct io_uring_params params;
314	memset(&params, 0, sizeof(params));
315	if( params_in.poll_submit ) params.flags \|= IORING_SETUP_SQPOLL;
316	if( params_in.poll_complete ) params.flags \|= IORING_SETUP_IOPOLL;
317
318	__u32 nentries = params_in.num_entries != 0 ? params_in.num_entries : 256;
319	if( !is_pow2(nentries) ) {
320	abort("ERROR: I/O setup 'num_entries' must be a power of 2\n");
321	}
322	if( params_in.poller_submits && params_in.eager_submits ) {
323	abort("ERROR: I/O setup 'poller_submits' and 'eager_submits' cannot be used together\n");
324	}
325
326	int fd = syscall(__NR_io_uring_setup, nentries, &params );
327	if(fd < 0) {
328	abort("KERNEL ERROR: IO_URING SETUP - %s\n", strerror(errno));
329	}
330
331	// Step 2 : mmap result
332	memset( &this, 0, sizeof(struct __io_data) );
333	struct __submition_data & sq = this.submit_q;
334	struct __completion_data & cq = this.completion_q;
335
336	// calculate the right ring size
337	sq.ring_sz = params.sq_off.array + (params.sq_entries * sizeof(unsigned) );
338	cq.ring_sz = params.cq_off.cqes + (params.cq_entries * sizeof(struct io_uring_cqe));
339
340	// Requires features
341	#if defined(IORING_FEAT_SINGLE_MMAP)
342	// adjust the size according to the parameters
343	if ((params.features & IORING_FEAT_SINGLE_MMAP) != 0) {
344	cq.ring_sz = sq.ring_sz = max(cq.ring_sz, sq.ring_sz);
345	}
346	#endif
347
348	// mmap the Submit Queue into existence
349	sq.ring_ptr = mmap(0, sq.ring_sz, PROT_READ \| PROT_WRITE, MAP_SHARED \| MAP_POPULATE, fd, IORING_OFF_SQ_RING);
350	if (sq.ring_ptr == (void*)MAP_FAILED) {
351	abort("KERNEL ERROR: IO_URING MMAP1 - %s\n", strerror(errno));
352	}
353
354	// Requires features
355	#if defined(IORING_FEAT_SINGLE_MMAP)
356	// mmap the Completion Queue into existence (may or may not be needed)
357	if ((params.features & IORING_FEAT_SINGLE_MMAP) != 0) {
358	cq.ring_ptr = sq.ring_ptr;
359	}
360	else
361	#endif
362	{
363	// We need multiple call to MMAP
364	cq.ring_ptr = mmap(0, cq.ring_sz, PROT_READ \| PROT_WRITE, MAP_SHARED \| MAP_POPULATE, fd, IORING_OFF_CQ_RING);
365	if (cq.ring_ptr == (void*)MAP_FAILED) {
366	munmap(sq.ring_ptr, sq.ring_sz);
367	abort("KERNEL ERROR: IO_URING MMAP2 - %s\n", strerror(errno));
368	}
369	}
370
371	// mmap the submit queue entries
372	size_t size = params.sq_entries * sizeof(struct io_uring_sqe);
373	sq.sqes = (struct io_uring_sqe *)mmap(0, size, PROT_READ \| PROT_WRITE, MAP_SHARED \| MAP_POPULATE, fd, IORING_OFF_SQES);
374	if (sq.sqes == (struct io_uring_sqe *)MAP_FAILED) {
375	munmap(sq.ring_ptr, sq.ring_sz);
376	if (cq.ring_ptr != sq.ring_ptr) munmap(cq.ring_ptr, cq.ring_sz);
377	abort("KERNEL ERROR: IO_URING MMAP3 - %s\n", strerror(errno));
378	}
379
380	// Get the pointers from the kernel to fill the structure
381	// submit queue
382	sq.head = (volatile __u32 *)(((intptr_t)sq.ring_ptr) + params.sq_off.head);
383	sq.tail = (volatile __u32 *)(((intptr_t)sq.ring_ptr) + params.sq_off.tail);
384	sq.mask = ( const __u32 *)(((intptr_t)sq.ring_ptr) + params.sq_off.ring_mask);
385	sq.num = ( const __u32 *)(((intptr_t)sq.ring_ptr) + params.sq_off.ring_entries);
386	sq.flags = ( __u32 *)(((intptr_t)sq.ring_ptr) + params.sq_off.flags);
387	sq.dropped = ( __u32 *)(((intptr_t)sq.ring_ptr) + params.sq_off.dropped);
388	sq.array = ( __u32 *)(((intptr_t)sq.ring_ptr) + params.sq_off.array);
389	sq.prev_head = *sq.head;
390
391	{
392	const __u32 num = *sq.num;
393	for( i; num ) {
394	sq.sqes[i].user_data = 0ul64;
395	}
396	}
397
398	(sq.submit_lock){};
399	(sq.release_lock){};
400
401	if( params_in.poller_submits \|\| params_in.eager_submits ) {
402	/* paranoid */ verify( is_pow2( params_in.num_ready ) \|\| (params_in.num_ready < 8) );
403	sq.ready_cnt = max( params_in.num_ready, 8 );
404	sq.ready = alloc( sq.ready_cnt, 64`align );
405	for(i; sq.ready_cnt) {
406	sq.ready[i] = -1ul32;
407	}
408	sq.prev_ready = 0;
409	}
410	else {
411	sq.ready_cnt = 0;
412	sq.ready = 0p;
413	sq.prev_ready = 0;
414	}
415
416	// completion queue
417	cq.head = (volatile __u32 *)(((intptr_t)cq.ring_ptr) + params.cq_off.head);
418	cq.tail = (volatile __u32 *)(((intptr_t)cq.ring_ptr) + params.cq_off.tail);
419	cq.mask = ( const __u32 *)(((intptr_t)cq.ring_ptr) + params.cq_off.ring_mask);
420	cq.num = ( const __u32 *)(((intptr_t)cq.ring_ptr) + params.cq_off.ring_entries);
421	cq.overflow = ( __u32 *)(((intptr_t)cq.ring_ptr) + params.cq_off.overflow);
422	cq.cqes = (struct io_uring_cqe *)(((intptr_t)cq.ring_ptr) + params.cq_off.cqes);
423
424	// some paranoid checks
425	/* 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 );
426	/* paranoid / verifyf( (cq.num) >= nentries, "IO_URING Expected %u entries, got %u", nentries, *cq.num );
427	/* paranoid / verifyf( (cq.head) == 0, "IO_URING Expected head to be 0, got %u", *cq.head );
428	/* paranoid / verifyf( (cq.tail) == 0, "IO_URING Expected tail to be 0, got %u", *cq.tail );
429
430	/* 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 );
431	/* paranoid / verifyf( (sq.num) >= nentries, "IO_URING Expected %u entries, got %u", nentries, *sq.num );
432	/* paranoid / verifyf( (sq.head) == 0, "IO_URING Expected head to be 0, got %u", *sq.head );
433	/* paranoid / verifyf( (sq.tail) == 0, "IO_URING Expected tail to be 0, got %u", *sq.tail );
434
435	// Update the global ring info
436	this.ring_flags = params.flags;
437	this.fd = fd;
438	this.eager_submits = params_in.eager_submits;
439	this.poller_submits = params_in.poller_submits;
440	}
441
442	static void __io_destroy( __io_data & this ) {
443	// Shutdown the io rings
444	struct __submition_data & sq = this.submit_q;
445	struct __completion_data & cq = this.completion_q;
446
447	// unmap the submit queue entries
448	munmap(sq.sqes, (sq.num) sizeof(struct io_uring_sqe));
449
450	// unmap the Submit Queue ring
451	munmap(sq.ring_ptr, sq.ring_sz);
452
453	// unmap the Completion Queue ring, if it is different
454	if (cq.ring_ptr != sq.ring_ptr) {
455	munmap(cq.ring_ptr, cq.ring_sz);
456	}
457
458	// close the file descriptor
459	close(this.fd);
460
461	free( this.submit_q.ready ); // Maybe null, doesn't matter
462	}
463
464	//=============================================================================================
465	// I/O Context Sleep
466	//=============================================================================================
467
468	void __ioctx_register($io_ctx_thread & ctx, struct epoll_event & ev) {
469	ev.events = EPOLLIN \| EPOLLONESHOT;
470	ev.data.u64 = (__u64)&ctx;
471	int ret = epoll_ctl(iopoll.epollfd, EPOLL_CTL_ADD, ctx.ring->fd, &ev);
472	if (ret < 0) {
473	abort( "KERNEL ERROR: EPOLL ADD - (%d) %s\n", (int)errno, strerror(errno) );
474	}
475	}
476
477	void __ioctx_prepare_block($io_ctx_thread & ctx, struct epoll_event & ev) {
478	__cfadbg_print_safe(io_core, "Kernel I/O - epoll : Re-arming io poller %p\n", &ctx);
479	int ret = epoll_ctl(iopoll.epollfd, EPOLL_CTL_MOD, ctx.ring->fd, &ev);
480	if (ret < 0) {
481	abort( "KERNEL ERROR: EPOLL REARM - (%d) %s\n", (int)errno, strerror(errno) );
482	}
483	}
484
485	//=============================================================================================
486	// I/O Context Misc Setup
487	//=============================================================================================
488	void register_fixed_files( io_context & ctx, int * files, unsigned count ) {
489	int ret = syscall( __NR_io_uring_register, ctx.thrd.ring->fd, IORING_REGISTER_FILES, files, count );
490	if( ret < 0 ) {
491	abort( "KERNEL ERROR: IO_URING SYSCALL - (%d) %s\n", (int)errno, strerror(errno) );
492	}
493
494	__cfadbg_print_safe( io_core, "Kernel I/O : Performed io_register for %p, returned %d\n", active_thread(), ret );
495	}
496
497	void register_fixed_files( cluster & cltr, int * files, unsigned count ) {
498	for(i; cltr.io.cnt) {
499	register_fixed_files( cltr.io.ctxs[i], files, count );
500	}
501	}
502	#endif

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