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setup.cfa @ 9f99799

ADTast-experimentalpthread-emulation

Last change on this file since 9f99799 was 19cb0cb, checked in by Thierry Delisle <tdelisle@…>, 2 years ago
Added comments and fixed scoping
Property mode set to `100644`
File size: 13.3 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
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 ?{}(io_context_params & this) libcfa_public {}
29
30	void ?{}(io_context$ & this, struct cluster & cl) {}
31	void ^?{}(io_context$ & this) {}
32
33	void __cfa_io_start( processor * proc ) {}
34	bool __cfa_io_flush( processor * proc ) { return false; }
35	bool __cfa_io_drain( processor * proc ) __attribute__((nonnull (1))) { return false; }
36	void __cfa_io_idle ( processor * ) __attribute__((nonnull (1))) {}
37	void __cfa_io_stop ( processor * proc ) {}
38
39	io_arbiter$ * create(void) { return 0p; }
40	void destroy(io_arbiter$ *) {}
41
42	#else
43	#pragma GCC diagnostic push
44	#pragma GCC diagnostic ignored "-Waddress-of-packed-member"
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/eventfd.h>
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 "fstream.hfa"
63	#include "kernel/private.hfa"
64	#include "limits.hfa"
65	#include "thread.hfa"
66	#pragma GCC diagnostic pop
67
68	void ?{}(io_context_params & this) libcfa_public {
69	this.num_entries = 256;
70	}
71
72	static void * __io_poller_slow( void * arg );
73
74	// Weirdly, some systems that do support io_uring don't actually define these
75	#ifdef __alpha__
76	/*
77	* alpha is the only exception, all other architectures
78	* have common numbers for new system calls.
79	*/
80	#ifndef __NR_io_uring_setup
81	#define __NR_io_uring_setup 535
82	#endif
83	#ifndef __NR_io_uring_enter
84	#define __NR_io_uring_enter 536
85	#endif
86	#ifndef __NR_io_uring_register
87	#define __NR_io_uring_register 537
88	#endif
89	#else /* !__alpha__ */
90	#ifndef __NR_io_uring_setup
91	#define __NR_io_uring_setup 425
92	#endif
93	#ifndef __NR_io_uring_enter
94	#define __NR_io_uring_enter 426
95	#endif
96	#ifndef __NR_io_uring_register
97	#define __NR_io_uring_register 427
98	#endif
99	#endif
100
101	//=============================================================================================
102	// I/O Context Constrution/Destruction
103	//=============================================================================================
104
105
106
107	static void __io_uring_setup ( io_context$ & this, const io_context_params & params_in, int procfd );
108	static void __io_uring_teardown( io_context$ & this );
109	static void __epoll_register(io_context$ & ctx);
110	static void __epoll_unregister(io_context$ & ctx);
111	void __ioarbiter_register( io_arbiter$ & mutex, io_context$ & ctx );
112	void __ioarbiter_unregister( io_arbiter$ & mutex, io_context$ & ctx );
113
114	void ?{}(io_context$ & this, processor * proc, struct cluster & cl) {
115	/* paranoid */ verify( cl.io.arbiter );
116	this.proc = proc;
117	this.arbiter = cl.io.arbiter;
118	this.ext_sq.empty = true;
119	(this.ext_sq.queue){};
120	__io_uring_setup( this, cl.io.params, proc->idle_wctx.evfd );
121	__cfadbg_print_safe(io_core, "Kernel I/O : Created ring for io_context %u (%p)\n", this.fd, &this);
122	}
123
124	void ^?{}(io_context$ & this) {
125	__cfadbg_print_safe(io_core, "Kernel I/O : tearing down io_context %u\n", this.fd);
126
127	__io_uring_teardown( this );
128	__cfadbg_print_safe(io_core, "Kernel I/O : Destroyed ring for io_context %u\n", this.fd);
129	}
130
131	static void __io_uring_setup( io_context$ & this, const io_context_params & params_in, int procfd ) {
132	// Step 1 : call to setup
133	struct io_uring_params params;
134	memset(&params, 0, sizeof(params));
135	// if( params_in.poll_submit ) params.flags \|= IORING_SETUP_SQPOLL;
136	// if( params_in.poll_complete ) params.flags \|= IORING_SETUP_IOPOLL;
137
138	__u32 nentries = params_in.num_entries != 0 ? params_in.num_entries : 256;
139	if( !is_pow2(nentries) ) {
140	abort("ERROR: I/O setup 'num_entries' must be a power of 2, was %u\n", nentries);
141	}
142
143	int fd = syscall(__NR_io_uring_setup, nentries, &params );
144	if(fd < 0) {
145	abort("KERNEL ERROR: IO_URING SETUP - %s\n", strerror(errno));
146	}
147
148	// Step 2 : mmap result
149	struct __sub_ring_t & sq = this.sq;
150	struct __cmp_ring_t & cq = this.cq;
151
152	// calculate the right ring size
153	sq.ring_sz = params.sq_off.array + (params.sq_entries * sizeof(unsigned) );
154	cq.ring_sz = params.cq_off.cqes + (params.cq_entries * sizeof(struct io_uring_cqe));
155
156	// Requires features
157	#if defined(IORING_FEAT_SINGLE_MMAP)
158	// adjust the size according to the parameters
159	if ((params.features & IORING_FEAT_SINGLE_MMAP) != 0) {
160	cq.ring_sz = sq.ring_sz = max(cq.ring_sz, sq.ring_sz);
161	}
162	#endif
163
164	// mmap the Submit Queue into existence
165	sq.ring_ptr = mmap(0, sq.ring_sz, PROT_READ \| PROT_WRITE, MAP_SHARED \| MAP_POPULATE, fd, IORING_OFF_SQ_RING);
166	if (sq.ring_ptr == (void*)MAP_FAILED) {
167	abort("KERNEL ERROR: IO_URING MMAP1 - %s\n", strerror(errno));
168	}
169
170	// Requires features
171	#if defined(IORING_FEAT_SINGLE_MMAP)
172	// mmap the Completion Queue into existence (may or may not be needed)
173	if ((params.features & IORING_FEAT_SINGLE_MMAP) != 0) {
174	cq.ring_ptr = sq.ring_ptr;
175	}
176	else
177	#endif
178	{
179	// We need multiple call to MMAP
180	cq.ring_ptr = mmap(0, cq.ring_sz, PROT_READ \| PROT_WRITE, MAP_SHARED \| MAP_POPULATE, fd, IORING_OFF_CQ_RING);
181	if (cq.ring_ptr == (void*)MAP_FAILED) {
182	munmap(sq.ring_ptr, sq.ring_sz);
183	abort("KERNEL ERROR: IO_URING MMAP2 - %s\n", strerror(errno));
184	}
185	}
186
187	// mmap the submit queue entries
188	size_t size = params.sq_entries * sizeof(struct io_uring_sqe);
189	sq.sqes = (struct io_uring_sqe *)mmap(0, size, PROT_READ \| PROT_WRITE, MAP_SHARED \| MAP_POPULATE, fd, IORING_OFF_SQES);
190	if (sq.sqes == (struct io_uring_sqe *)MAP_FAILED) {
191	munmap(sq.ring_ptr, sq.ring_sz);
192	if (cq.ring_ptr != sq.ring_ptr) munmap(cq.ring_ptr, cq.ring_sz);
193	abort("KERNEL ERROR: IO_URING MMAP3 - %s\n", strerror(errno));
194	}
195
196	// Step 3 : Initialize the data structure
197	// Get the pointers from the kernel to fill the structure
198	// submit queue
199	sq.kring.head = (volatile __u32 *)(((intptr_t)sq.ring_ptr) + params.sq_off.head);
200	sq.kring.tail = (volatile __u32 *)(((intptr_t)sq.ring_ptr) + params.sq_off.tail);
201	sq.kring.array = ( __u32 *)(((intptr_t)sq.ring_ptr) + params.sq_off.array);
202	sq.mask = ( const __u32 *)(((intptr_t)sq.ring_ptr) + params.sq_off.ring_mask);
203	sq.num = ( const __u32 *)(((intptr_t)sq.ring_ptr) + params.sq_off.ring_entries);
204	sq.flags = ( __u32 *)(((intptr_t)sq.ring_ptr) + params.sq_off.flags);
205	sq.dropped = ( __u32 *)(((intptr_t)sq.ring_ptr) + params.sq_off.dropped);
206
207	sq.kring.released = 0;
208
209	sq.free_ring.head = 0;
210	sq.free_ring.tail = *sq.num;
211	sq.free_ring.array = alloc( *sq.num, 128`align );
212	for(i; (__u32)*sq.num) {
213	sq.free_ring.array[i] = i;
214	}
215
216	sq.to_submit = 0;
217
218	// completion queue
219	cq.lock = false;
220	cq.id = MAX;
221	cq.ts = rdtscl();
222	cq.head = (volatile __u32 *)(((intptr_t)cq.ring_ptr) + params.cq_off.head);
223	cq.tail = (volatile __u32 *)(((intptr_t)cq.ring_ptr) + params.cq_off.tail);
224	cq.mask = ( const __u32 *)(((intptr_t)cq.ring_ptr) + params.cq_off.ring_mask);
225	cq.num = ( const __u32 *)(((intptr_t)cq.ring_ptr) + params.cq_off.ring_entries);
226	cq.overflow = ( __u32 *)(((intptr_t)cq.ring_ptr) + params.cq_off.overflow);
227	cq.cqes = (struct io_uring_cqe *)(((intptr_t)cq.ring_ptr) + params.cq_off.cqes);
228
229	#if !defined(CFA_WITH_IO_URING_IDLE)
230	{
231	// Step 4 : eventfd
232	__cfadbg_print_safe(io_core, "Kernel I/O : registering %d for completion with ring %d\n", procfd, fd);
233
234	int ret = syscall( __NR_io_uring_register, fd, IORING_REGISTER_EVENTFD, &procfd, 1);
235	if (ret < 0) {
236	abort("KERNEL ERROR: IO_URING EVENTFD REGISTER - %s\n", strerror(errno));
237	}
238
239	__cfadbg_print_safe(io_core, "Kernel I/O : registered %d for completion with ring %d\n", procfd, fd);
240	}
241	#endif
242
243	// TODO: implement a proper version of this.
244	// I have not found a better maximum that works in general but users should be able to configure it
245	// the same way they configure other I/O options
246	// #if defined(CFA_HAVE_IORING_REGISTER_IOWQ_MAX_WORKERS)
247	// {
248	// // Step 5 : max worker count
249	// __cfadbg_print_safe(io_core, "Kernel I/O : lmiting max workers for ring %d\n", fd);
250
251	// unsigned int maxes[2];
252	// maxes[0] = 64; // max number of bounded workers (Regular files / block)
253	// maxes[1] = 64; // max number of unbounded workers (IOSQE_ASYNC)
254	// int ret = syscall( __NR_io_uring_register, fd, IORING_REGISTER_IOWQ_MAX_WORKERS, maxes, 2);
255	// if (ret < 0) {
256	// abort("KERNEL ERROR: IO_URING MAX WORKER REGISTER - %s\n", strerror(errno));
257	// }
258
259	// __cfadbg_print_safe(io_core, "Kernel I/O : lmited max workers for ring %d\n", fd);
260	// }
261	// #endif
262
263	// some paranoid checks
264	/* 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 );
265	/* paranoid / verifyf( (cq.num) >= nentries, "IO_URING Expected %u entries, got %u", nentries, *cq.num );
266	/* paranoid / verifyf( (cq.head) == 0, "IO_URING Expected head to be 0, got %u", *cq.head );
267	/* paranoid / verifyf( (cq.tail) == 0, "IO_URING Expected tail to be 0, got %u", *cq.tail );
268
269	/* 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 );
270	/* paranoid / verifyf( (sq.num) >= nentries, "IO_URING Expected %u entries, got %u", nentries, *sq.num );
271	/* paranoid / verifyf( (sq.kring.head) == 0, "IO_URING Expected head to be 0, got %u", *sq.kring.head );
272	/* paranoid / verifyf( (sq.kring.tail) == 0, "IO_URING Expected tail to be 0, got %u", *sq.kring.tail );
273
274	// Update the global ring info
275	this.ring_flags = 0;
276	this.fd = fd;
277	}
278
279	static void __io_uring_teardown( io_context$ & this ) {
280	// Shutdown the io rings
281	struct __sub_ring_t & sq = this.sq;
282	struct __cmp_ring_t & cq = this.cq;
283	{
284	__u32 fhead = sq.free_ring.head;
285	__u32 ftail = sq.free_ring.tail;
286
287	__u32 total = *sq.num;
288	__u32 avail = ftail - fhead;
289
290	if(avail != total) abort \| "Processor (" \| (void*)this.proc \| ") tearing down ring with" \| (total - avail) \| "entries allocated but not submitted, out of" \| total;
291	}
292
293	// unmap the submit queue entries
294	munmap(sq.sqes, (sq.num) sizeof(struct io_uring_sqe));
295
296	// unmap the Submit Queue ring
297	munmap(sq.ring_ptr, sq.ring_sz);
298
299	// unmap the Completion Queue ring, if it is different
300	if (cq.ring_ptr != sq.ring_ptr) {
301	munmap(cq.ring_ptr, cq.ring_sz);
302	}
303
304	// close the file descriptor
305	close(this.fd);
306
307	free( this.sq.free_ring.array ); // Maybe null, doesn't matter
308	}
309
310	void __cfa_io_start( processor * proc ) {
311	proc->io.ctx = alloc();
312	(proc->io.ctx){proc, proc->cltr};
313	}
314	void __cfa_io_stop ( processor * proc ) {
315	^(*proc->io.ctx){};
316	free(proc->io.ctx);
317	}
318
319	//=============================================================================================
320	// I/O Context Sleep
321	//=============================================================================================
322	// static inline void __epoll_ctl(io_context$ & ctx, int op, const char * error) {
323	// struct epoll_event ev;
324	// ev.events = EPOLLIN \| EPOLLONESHOT;
325	// ev.data.u64 = (__u64)&ctx;
326	// int ret = epoll_ctl(iopoll.epollfd, op, ctx.efd, &ev);
327	// if (ret < 0) {
328	// abort( "KERNEL ERROR: EPOLL %s - (%d) %s\n", error, (int)errno, strerror(errno) );
329	// }
330	// }
331
332	// static void __epoll_register(io_context$ & ctx) {
333	// __epoll_ctl(ctx, EPOLL_CTL_ADD, "ADD");
334	// }
335
336	// static void __epoll_unregister(io_context$ & ctx) {
337	// // Read the current epoch so we know when to stop
338	// size_t curr = __atomic_load_n(&iopoll.epoch, __ATOMIC_SEQ_CST);
339
340	// // Remove the fd from the iopoller
341	// __epoll_ctl(ctx, EPOLL_CTL_DEL, "REMOVE");
342
343	// // Notify the io poller thread of the shutdown
344	// iopoll.run = false;
345	// sigval val = { 1 };
346	// pthread_sigqueue( iopoll.thrd, SIGUSR1, val );
347
348	// // Make sure all this is done
349	// __atomic_thread_fence(__ATOMIC_SEQ_CST);
350
351	// // Wait for the next epoch
352	// while(curr == iopoll.epoch && !iopoll.stopped) Pause();
353	// }
354
355	// void __ioctx_prepare_block(io_context$ & ctx) {
356	// __cfadbg_print_safe(io_core, "Kernel I/O - epoll : Re-arming io poller %d (%p)\n", ctx.fd, &ctx);
357	// __epoll_ctl(ctx, EPOLL_CTL_MOD, "REARM");
358	// }
359
360
361	//=============================================================================================
362	// I/O Context Misc Setup
363	//=============================================================================================
364	void ?{}( io_arbiter$ & this ) {
365	this.pending.empty = true;
366	}
367
368	void ^?{}( io_arbiter$ & mutex this ) {}
369
370	io_arbiter$ * create(void) {
371	return new();
372	}
373	void destroy(io_arbiter$ * arbiter) {
374	delete(arbiter);
375	}
376
377	//=============================================================================================
378	// I/O Context Misc Setup
379	//=============================================================================================
380
381	#endif

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