source: trunk/kernel/kern/chdev.c@ 438

Last change on this file since 438 was 438, checked in by alain, 8 years ago

Fix a bug in scheduler related to RPC blocking.
File size: 15.0 KB
Line 
1/*
2 * chdev.c - channel device descriptor operations implementation.
3 *
4 * Authors Alain Greiner (2016)
5 *
6 * Copyright (c) UPMC Sorbonne Universites
7 *
8 * This file is part of ALMOS-MKH.
9 *
10 * ALMOS-MKH.is free software; you can redistribute it and/or modify it
11 * under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; version 2.0 of the License.
13 *
14 * ALMOS-MKH.is distributed in the hope that it will be useful, but
15 * WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License
20 * along with ALMOS-MKH.; if not, write to the Free Software Foundation,
21 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
22 */
23
24#include <kernel_config.h>
25#include <hal_types.h>
26#include <hal_special.h>
27#include <hal_irqmask.h>
28#include <printk.h>
29#include <boot_info.h>
30#include <xlist.h>
31#include <kmem.h>
32#include <scheduler.h>
33#include <thread.h>
34#include <rpc.h>
35#include <chdev.h>
36#include <devfs.h>
37
38
39extern chdev_directory_t chdev_dir; // allocated in kernel_init.c
40
41#if (DEBUG_SYS_READ & 1)
42extern uint32_t enter_chdev_cmd_read;
43extern uint32_t exit_chdev_cmd_read;
44extern uint32_t enter_chdev_server_read;
45extern uint32_t exit_chdev_server_read;
46#endif
47
48#if (DEBUG_SYS_WRITE & 1)
49extern uint32_t enter_chdev_cmd_write;
50extern uint32_t exit_chdev_cmd_write;
51extern uint32_t enter_chdev_server_write;
52extern uint32_t exit_chdev_server_write;
53#endif
54
55////////////////////////////////////////////
56char * chdev_func_str( uint32_t func_type )
57{
58 if ( func_type == DEV_FUNC_RAM ) return "RAM";
59 else if( func_type == DEV_FUNC_ROM ) return "ROM";
60 else if( func_type == DEV_FUNC_FBF ) return "FBF";
61 else if( func_type == DEV_FUNC_IOB ) return "IOB";
62 else if( func_type == DEV_FUNC_IOC ) return "IOC";
63 else if( func_type == DEV_FUNC_MMC ) return "MMC";
64 else if( func_type == DEV_FUNC_DMA ) return "DMA";
65 else if( func_type == DEV_FUNC_NIC ) return "NIC";
66 else if( func_type == DEV_FUNC_TIM ) return "TIM";
67 else if( func_type == DEV_FUNC_TXT ) return "TXT";
68 else if( func_type == DEV_FUNC_ICU ) return "ICU";
69 else if( func_type == DEV_FUNC_PIC ) return "PIC";
70 else return "undefined";
71}
72
73/////////////////////////////////////////
74chdev_t * chdev_create( uint32_t func,
75 uint32_t impl,
76 uint32_t channel,
77 uint32_t is_rx,
78 xptr_t base )
79{
80 chdev_t * chdev;
81 kmem_req_t req;
82
83 // allocate memory for chdev
84 req.type = KMEM_DEVICE;
85 req.flags = AF_ZERO;
86 chdev = (chdev_t *)kmem_alloc( &req );
87
88 if( chdev == NULL ) return NULL;
89
90 // initialize waiting threads queue and associated lock
91 remote_spinlock_init( XPTR( local_cxy , &chdev->wait_lock ) );
92 xlist_root_init( XPTR( local_cxy , &chdev->wait_root ) );
93
94 // initialize attributes
95 chdev->func = func;
96 chdev->impl = impl;
97 chdev->channel = channel;
98 chdev->is_rx = is_rx;
99 chdev->base = base;
100
101 return chdev;
102
103} // end chdev_create()
104
105///////////////////////////////////
106void chdev_print( chdev_t * chdev )
107{
108 printk("\n - func = %s"
109 "\n - channel = %d"
110 "\n - base = %l"
111 "\n - cmd = %x"
112 "\n - isr = %x"
113 "\n - chdev = %x\n",
114 chdev_func_str(chdev->func),
115 chdev->channel,
116 chdev->base,
117 chdev->cmd,
118 chdev->isr,
119 chdev );
120}
121
122//////////////////////////////////////////////////
123void chdev_register_command( xptr_t chdev_xp )
124{
125 thread_t * server_ptr; // local pointer on server thread associated to chdev
126 core_t * core_ptr; // local pointer on core running the server thread
127 uint32_t lid; // core running the server thread local index
128 xptr_t lock_xp; // extended pointer on lock protecting the chdev queue
129 uint32_t different; // non zero if server thread core != client thread core
130 uint32_t save_sr; // for critical section
131
132#if (DEBUG_SYS_READ & 1)
133enter_chdev_cmd_read = (uint32_t)hal_get_cycles();
134#endif
135
136#if (DEBUG_SYS_WRITE & 1)
137enter_chdev_cmd_write = (uint32_t)hal_get_cycles();
138#endif
139
140 thread_t * this = CURRENT_THREAD;
141
142 // get device descriptor cluster and local pointer
143 cxy_t chdev_cxy = GET_CXY( chdev_xp );
144 chdev_t * chdev_ptr = (chdev_t *)GET_PTR( chdev_xp );
145
146#if (DEBUG_CHDEV_CMD_RX || DEBUG_CHDEV_CMD_TX)
147bool_t is_rx = hal_remote_lw( XPTR( chdev_cxy , &chdev_ptr->is_rx ) );
148#endif
149
150#if DEBUG_CHDEV_CMD_RX
151uint32_t rx_cycle = (uint32_t)hal_get_cycles();
152if( (is_rx) && (DEBUG_CHDEV_CMD_RX < rx_cycle) )
153printk("\n[DBG] %s : client_thread %x (%s) enter for RX / cycle %d\n",
154__FUNCTION__, this, thread_type_str(this->type) , rx_cycle );
155#endif
156
157#if DEBUG_CHDEV_CMD_TX
158uint32_t tx_cycle = (uint32_t)hal_get_cycles();
159if( (is_rx == 0) && (DEBUG_CHDEV_CMD_TX < tx_cycle) )
160printk("\n[DBG] %s : client_thread %x (%s) enter for TX / cycle %d\n",
161__FUNCTION__, this, thread_type_str(this->type) , tx_cycle );
162#endif
163
164 // build extended pointers on client thread xlist and device root
165 xptr_t list_xp = XPTR( local_cxy , &this->wait_list );
166 xptr_t root_xp = XPTR( chdev_cxy , &chdev_ptr->wait_root );
167
168 // get local pointer on server thread
169 server_ptr = (thread_t *)hal_remote_lpt( XPTR( chdev_cxy , &chdev_ptr->server) );
170
171 // build extended pointer on chdev lock protecting queue
172 lock_xp = XPTR( chdev_cxy , &chdev_ptr->wait_lock );
173
174 // get local pointer on core running the server thread
175 core_ptr = (core_t *)hal_remote_lpt( XPTR( chdev_cxy , &server_ptr->core ) );
176
177 // get core local index
178 lid = hal_remote_lw( XPTR( chdev_cxy , &core_ptr->lid ) );
179
180 // compute server core != thread core
181 different = (lid != this->core->lid) || (local_cxy != chdev_cxy);
182
183 // enter critical section to make atomic :
184 // (1) client blocking
185 // (2) client registration in server queue
186 // (3) IPI to force server scheduling
187 // (4) descheduling
188 // ... in this order
189 hal_disable_irq( &save_sr );
190
191 // block current thread
192 thread_block( XPTR( local_cxy , CURRENT_THREAD ) , THREAD_BLOCKED_IO );
193
194 // register client thread in waiting queue
195 remote_spinlock_lock( lock_xp );
196 xlist_add_last( root_xp , list_xp );
197 remote_spinlock_unlock( lock_xp );
198
199 // send IPI to core running the server thread if required
200 if( different ) dev_pic_send_ipi( chdev_cxy , lid );
201
202 // deschedule
203 assert( thread_can_yield( this ) , __FUNCTION__ , "illegal sched_yield\n" );
204 sched_yield("blocked on I/O");
205
206 // exit critical section
207 hal_restore_irq( save_sr );
208
209#if DEBUG_CHDEV_CMD_RX
210rx_cycle = (uint32_t)hal_get_cycles();
211if( (is_rx) && (DEBUG_CHDEV_CMD_RX < rx_cycle) )
212printk("\n[DBG] %s : client_thread %x (%s) exit for RX / cycle %d\n",
213__FUNCTION__, this, thread_type_str(this->type) , rx_cycle );
214#endif
215
216#if DEBUG_CHDEV_CMD_TX
217tx_cycle = (uint32_t)hal_get_cycles();
218if( (is_rx == 0) && (DEBUG_CHDEV_CMD_TX < tx_cycle) )
219printk("\n[DBG] %s : client_thread %x (%s) exit for TX / cycle %d\n",
220__FUNCTION__, this, thread_type_str(this->type) , tx_cycle );
221#endif
222
223#if (DEBUG_SYS_READ & 1)
224exit_chdev_cmd_read = (uint32_t)hal_get_cycles();
225#endif
226
227#if (DEBUG_SYS_WRITE & 1)
228exit_chdev_cmd_write = (uint32_t)hal_get_cycles();
229#endif
230
231} // end chdev_register_command()
232
233///////////////////////////////////////////////
234void chdev_sequencial_server( chdev_t * chdev )
235{
236 xptr_t client_xp; // extended pointer on waiting thread
237 cxy_t client_cxy; // cluster of client thread
238 thread_t * client_ptr; // local pointer on client thread
239 thread_t * server; // local pointer on server thread
240 xptr_t root_xp; // extended pointer on device waiting queue root
241 xptr_t lock_xp; // extended pointer on lock ptotecting chdev queue
242
243 server = CURRENT_THREAD;
244
245 // get root and lock on command queue
246 root_xp = XPTR( local_cxy , &chdev->wait_root );
247 lock_xp = XPTR( local_cxy , &chdev->wait_lock );
248
249 // This infinite loop is executed by the DEV thread
250 // to handle commands registered in the chdev queue.
251 while( 1 )
252 {
253 // get the lock protecting the waiting queue
254 remote_spinlock_lock( lock_xp );
255
256 // check waiting queue state
257 if( xlist_is_empty( root_xp ) ) // waiting queue empty
258 {
259 // release lock
260 remote_spinlock_unlock( lock_xp );
261
262 // deschedule
263 sched_yield("I/O queue empty");
264 }
265 else // waiting queue not empty
266 {
267 // release lock
268 remote_spinlock_unlock( lock_xp );
269
270 // get extended pointer on first client thread
271 client_xp = XLIST_FIRST_ELEMENT( root_xp , thread_t , wait_list );
272
273 // get client thread cluster, local pointer, and identifier
274 client_cxy = GET_CXY( client_xp );
275 client_ptr = (thread_t *)GET_PTR( client_xp );
276
277#if DEBUG_CHDEV_SERVER_RX
278uint32_t rx_cycle = (uint32_t)hal_get_cycles();
279if( (chdev->is_rx) && (DEBUG_CHDEV_SERVER_RX < rx_cycle) )
280printk("\n[DBG] %s : server_thread %x start RX / client %x / cycle %d\n",
281__FUNCTION__ , server , client_ptr , rx_cycle );
282#endif
283
284#if DEBUG_CHDEV_SERVER_TX
285uint32_t tx_cycle = (uint32_t)hal_get_cycles();
286if( (chdev->is_rx == 0) && (DEBUG_CHDEV_SERVER_TX < tx_cycle) )
287printk("\n[DBG] %s : server_thread %x start TX / client %x / cycle %d\n",
288__FUNCTION__ , server , client_ptr , tx_cycle );
289#endif
290
291#if (DEBUG_SYS_READ & 1)
292enter_chdev_server_read = (uint32_t)hal_get_cycles();
293#endif
294
295#if (DEBUG_SYS_WRITE & 1)
296enter_chdev_server_write = (uint32_t)hal_get_cycles();
297#endif
298
299 // call driver command function to execute I/O operation
300 chdev->cmd( client_xp );
301
302 // remove the client thread from waiting queue
303 remote_spinlock_lock( lock_xp );
304 xlist_unlink( XPTR( client_cxy , &client_ptr->wait_list ) );
305 remote_spinlock_unlock( lock_xp );
306
307 // unblock client thread
308 thread_unblock( client_xp , THREAD_BLOCKED_IO );
309
310#if DEBUG_CHDEV_SERVER_RX
311rx_cycle = (uint32_t)hal_get_cycles();
312if( (chdev->is_rx) && (DEBUG_CHDEV_SERVER_RX < rx_cycle) )
313printk("\n[DBG] %s : server_thread %x completes RX / client %x / cycle %d\n",
314__FUNCTION__ , server , client_ptr , rx_cycle );
315#endif
316
317#if DEBUG_CHDEV_SERVER_TX
318tx_cycle = (uint32_t)hal_get_cycles();
319if( (chdev->is_rx == 0) && (DEBUG_CHDEV_SERVER_TX < tx_cycle) )
320printk("\n[DBG] %s : server_thread %x completes TX / client %x / cycle %d\n",
321__FUNCTION__ , server , client_ptr , tx_cycle );
322#endif
323
324#if (DEBUG_SYS_READ & 1)
325exit_chdev_server_read = (uint32_t)hal_get_cycles();
326#endif
327
328#if (DEBUG_SYS_WRITE & 1)
329exit_chdev_server_write = (uint32_t)hal_get_cycles();
330#endif
331
332 }
333 } // end while
334} // end chdev_sequencial_server()
335
336////////////////////////////////////////
337xptr_t chdev_from_file( xptr_t file_xp )
338{
339 cxy_t file_cxy;
340 vfs_file_t * file_ptr;
341 uint32_t inode_type;
342 vfs_inode_t * inode_ptr;
343 chdev_t * chdev_ptr;
344
345 // get cluster and local pointer on remote file descriptor
346 // associated inode and chdev are stored in same cluster as the file desc.
347 file_cxy = GET_CXY( file_xp );
348 file_ptr = (vfs_file_t *)GET_PTR( file_xp );
349
350 // get inode type from file descriptor
351 inode_type = hal_remote_lw( XPTR( file_cxy , &file_ptr->type ) );
352 inode_ptr = (vfs_inode_t *)hal_remote_lpt( XPTR( file_cxy , &file_ptr->inode ) );
353
354 assert( (inode_type == INODE_TYPE_DEV) , __FUNCTION__ ,
355 "inode type %d is not INODE_TYPE_DEV", inode_type );
356
357 // get chdev local pointer from inode extension
358 chdev_ptr = (chdev_t *)hal_remote_lpt( XPTR( file_cxy , &inode_ptr->extend ) );
359
360 return XPTR( file_cxy , chdev_ptr );
361
362} // end chdev_from_file()
363
364////////////////////////
365void chdev_dir_display()
366{
367 uint32_t i;
368 cxy_t cxy;
369 chdev_t * ptr;
370 uint32_t base;
371 reg_t save_sr;
372
373 // get pointers on TXT0 chdev
374 xptr_t txt0_xp = chdev_dir.txt_tx[0];
375 cxy_t txt0_cxy = GET_CXY( txt0_xp );
376 chdev_t * txt0_ptr = GET_PTR( txt0_xp );
377
378 // get extended pointer on remote TXT0 chdev lock
379 xptr_t lock_xp = XPTR( txt0_cxy , &txt0_ptr->wait_lock );
380
381 // get TXT0 lock in busy waiting mode
382 remote_spinlock_lock_busy( lock_xp , &save_sr );
383
384 // header
385 nolock_printk("\n***** external chdevs directory *****\n");
386
387 // IOB
388 cxy = GET_CXY( chdev_dir.iob );
389 ptr = GET_PTR( chdev_dir.iob );
390 base = (uint32_t)hal_remote_lwd( XPTR( cxy , &ptr->base ) );
391 nolock_printk(" - iob : cxy = %X / ptr = %X / base = %X\n", cxy, ptr, base);
392
393 // PIC
394 cxy = GET_CXY( chdev_dir.pic );
395 ptr = GET_PTR( chdev_dir.pic );
396 base = (uint32_t)hal_remote_lwd( XPTR( cxy , &ptr->base ) );
397 nolock_printk(" - pic : cxy = %X / ptr = %X / base = %X\n", cxy, ptr, base);
398
399 // TXT
400 for( i = 0 ; i < LOCAL_CLUSTER->nb_txt_channels ; i++ )
401 {
402 cxy = GET_CXY( chdev_dir.txt_rx[i] );
403 ptr = GET_PTR( chdev_dir.txt_rx[i] );
404 base = (uint32_t)hal_remote_lwd( XPTR( cxy , &ptr->base ) );
405 nolock_printk(" - txt_rx[%d] : cxy = %X / ptr = %X / base = %X\n", i, cxy, ptr, base);
406
407 cxy = GET_CXY( chdev_dir.txt_tx[i] );
408 ptr = GET_PTR( chdev_dir.txt_tx[i] );
409 base = (uint32_t)hal_remote_lwd( XPTR( cxy , &ptr->base ) );
410 nolock_printk(" - txt_tx[%d] : cxy = %X / ptr = %X / base = %X\n", i, cxy, ptr, base);
411 }
412
413 // IOC
414 for( i = 0 ; i < LOCAL_CLUSTER->nb_ioc_channels ; i++ )
415 {
416 cxy = GET_CXY( chdev_dir.ioc[i] );
417 ptr = GET_PTR( chdev_dir.ioc[i] );
418 base = (uint32_t)hal_remote_lwd( XPTR( cxy , &ptr->base ) );
419 nolock_printk(" - ioc[%d] : cxy = %X / ptr = %X / base = %X\n", i, cxy, ptr, base);
420 }
421
422 // FBF
423 for( i = 0 ; i < LOCAL_CLUSTER->nb_fbf_channels ; i++ )
424 {
425 cxy = GET_CXY( chdev_dir.fbf[i] );
426 ptr = GET_PTR( chdev_dir.fbf[i] );
427 base = (uint32_t)hal_remote_lwd( XPTR( cxy , &ptr->base ) );
428 nolock_printk(" - fbf[%d] : cxy = %X / ptr = %X / base = %X\n", i, cxy, ptr, base);
429 }
430
431 // NIC
432 for( i = 0 ; i < LOCAL_CLUSTER->nb_nic_channels ; i++ )
433 {
434 cxy = GET_CXY( chdev_dir.nic_rx[i] );
435 ptr = GET_PTR( chdev_dir.nic_rx[i] );
436 base = (uint32_t)hal_remote_lwd( XPTR( cxy , &ptr->base ) );
437 nolock_printk(" - nic_rx[%d] : cxy = %X / ptr = %X / base = %X\n", i, cxy, ptr, base);
438
439 cxy = GET_CXY( chdev_dir.nic_tx[i] );
440 ptr = GET_PTR( chdev_dir.nic_tx[i] );
441 base = (uint32_t)hal_remote_lwd( XPTR( cxy , &ptr->base ) );
442 nolock_printk(" - nic_tx[%d] : cxy = %X / ptr = %X / base = %X\n", i, cxy, ptr, base);
443 }
444
445 // release lock
446 remote_spinlock_unlock_busy( lock_xp , save_sr );
447
448} // end chdev_dir_display()
449
Note: See TracBrowser for help on using the repository browser.