4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 only,
8 * as published by the Free Software Foundation.
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License version 2 for more details (a copy is included
14 * in the LICENSE file that accompanied this code).
16 * You should have received a copy of the GNU General Public License
17 * version 2 along with this program; If not, see
18 * http://www.gnu.org/licenses/gpl-2.0.html
23 * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
24 * Use is subject to license terms.
26 * Copyright (c) 2012, Intel Corporation.
29 * This file is part of Lustre, http://www.lustre.org/
30 * Lustre is a trademark of Sun Microsystems, Inc.
32 * libcfs/libcfs/tracefile.c
34 * Author: Zach Brown <zab@clusterfs.com>
35 * Author: Phil Schwan <phil@clusterfs.com>
38 #define DEBUG_SUBSYSTEM S_LNET
39 #define LUSTRE_TRACEFILE_PRIVATE
40 #define pr_fmt(fmt) "Lustre: " fmt
41 #include "tracefile.h"
43 #include <linux/libcfs/libcfs.h>
45 /* XXX move things up to the top, comment */
46 union cfs_trace_data_union (*cfs_trace_data
[TCD_MAX_TYPES
])[NR_CPUS
] __cacheline_aligned
;
48 char cfs_tracefile
[TRACEFILE_NAME_SIZE
];
49 long long cfs_tracefile_size
= CFS_TRACEFILE_SIZE
;
50 static struct tracefiled_ctl trace_tctl
;
51 static DEFINE_MUTEX(cfs_trace_thread_mutex
);
52 static int thread_running
;
54 static atomic_t cfs_tage_allocated
= ATOMIC_INIT(0);
56 struct page_collection
{
57 struct list_head pc_pages
;
59 * if this flag is set, collect_pages() will spill both
60 * ->tcd_daemon_pages and ->tcd_pages to the ->pc_pages. Otherwise,
61 * only ->tcd_pages are spilled.
63 int pc_want_daemon_pages
;
66 struct tracefiled_ctl
{
67 struct completion tctl_start
;
68 struct completion tctl_stop
;
69 wait_queue_head_t tctl_waitq
;
71 atomic_t tctl_shutdown
;
75 * small data-structure for each page owned by tracefiled.
77 struct cfs_trace_page
{
83 * linkage into one of the lists in trace_data_union or
86 struct list_head linkage
;
88 * number of bytes used within this page
92 * cpu that owns this page
96 * type(context) of this page
101 static void put_pages_on_tcd_daemon_list(struct page_collection
*pc
,
102 struct cfs_trace_cpu_data
*tcd
);
104 static inline struct cfs_trace_page
*
105 cfs_tage_from_list(struct list_head
*list
)
107 return list_entry(list
, struct cfs_trace_page
, linkage
);
110 static struct cfs_trace_page
*cfs_tage_alloc(gfp_t gfp
)
113 struct cfs_trace_page
*tage
;
115 /* My caller is trying to free memory */
116 if (!in_interrupt() && memory_pressure_get())
120 * Don't spam console with allocation failures: they will be reported
121 * by upper layer anyway.
124 page
= alloc_page(gfp
);
128 tage
= kmalloc(sizeof(*tage
), gfp
);
135 atomic_inc(&cfs_tage_allocated
);
139 static void cfs_tage_free(struct cfs_trace_page
*tage
)
141 __free_page(tage
->page
);
143 atomic_dec(&cfs_tage_allocated
);
146 static void cfs_tage_to_tail(struct cfs_trace_page
*tage
,
147 struct list_head
*queue
)
149 list_move_tail(&tage
->linkage
, queue
);
152 int cfs_trace_refill_stock(struct cfs_trace_cpu_data
*tcd
, gfp_t gfp
,
153 struct list_head
*stock
)
158 * XXX nikita: do NOT call portals_debug_msg() (CDEBUG/ENTRY/EXIT)
159 * from here: this will lead to infinite recursion.
162 for (i
= 0; i
+ tcd
->tcd_cur_stock_pages
< TCD_STOCK_PAGES
; ++i
) {
163 struct cfs_trace_page
*tage
;
165 tage
= cfs_tage_alloc(gfp
);
168 list_add_tail(&tage
->linkage
, stock
);
173 /* return a page that has 'len' bytes left at the end */
174 static struct cfs_trace_page
*
175 cfs_trace_get_tage_try(struct cfs_trace_cpu_data
*tcd
, unsigned long len
)
177 struct cfs_trace_page
*tage
;
179 if (tcd
->tcd_cur_pages
> 0) {
180 __LASSERT(!list_empty(&tcd
->tcd_pages
));
181 tage
= cfs_tage_from_list(tcd
->tcd_pages
.prev
);
182 if (tage
->used
+ len
<= PAGE_SIZE
)
186 if (tcd
->tcd_cur_pages
< tcd
->tcd_max_pages
) {
187 if (tcd
->tcd_cur_stock_pages
> 0) {
188 tage
= cfs_tage_from_list(tcd
->tcd_stock_pages
.prev
);
189 --tcd
->tcd_cur_stock_pages
;
190 list_del_init(&tage
->linkage
);
192 tage
= cfs_tage_alloc(GFP_ATOMIC
);
193 if (unlikely(!tage
)) {
194 if (!memory_pressure_get() || in_interrupt())
195 pr_warn_ratelimited("cannot allocate a tage (%ld)\n",
202 tage
->cpu
= smp_processor_id();
203 tage
->type
= tcd
->tcd_type
;
204 list_add_tail(&tage
->linkage
, &tcd
->tcd_pages
);
205 tcd
->tcd_cur_pages
++;
207 if (tcd
->tcd_cur_pages
> 8 && thread_running
) {
208 struct tracefiled_ctl
*tctl
= &trace_tctl
;
210 * wake up tracefiled to process some pages.
212 wake_up(&tctl
->tctl_waitq
);
219 static void cfs_tcd_shrink(struct cfs_trace_cpu_data
*tcd
)
221 int pgcount
= tcd
->tcd_cur_pages
/ 10;
222 struct page_collection pc
;
223 struct cfs_trace_page
*tage
;
224 struct cfs_trace_page
*tmp
;
227 * XXX nikita: do NOT call portals_debug_msg() (CDEBUG/ENTRY/EXIT)
228 * from here: this will lead to infinite recursion.
231 pr_warn_ratelimited("debug daemon buffer overflowed; discarding 10%% of pages (%d of %ld)\n",
232 pgcount
+ 1, tcd
->tcd_cur_pages
);
234 INIT_LIST_HEAD(&pc
.pc_pages
);
236 list_for_each_entry_safe(tage
, tmp
, &tcd
->tcd_pages
, linkage
) {
240 list_move_tail(&tage
->linkage
, &pc
.pc_pages
);
241 tcd
->tcd_cur_pages
--;
243 put_pages_on_tcd_daemon_list(&pc
, tcd
);
246 /* return a page that has 'len' bytes left at the end */
247 static struct cfs_trace_page
*cfs_trace_get_tage(struct cfs_trace_cpu_data
*tcd
,
250 struct cfs_trace_page
*tage
;
253 * XXX nikita: do NOT call portals_debug_msg() (CDEBUG/ENTRY/EXIT)
254 * from here: this will lead to infinite recursion.
257 if (len
> PAGE_SIZE
) {
258 pr_err("cowardly refusing to write %lu bytes in a page\n", len
);
262 tage
= cfs_trace_get_tage_try(tcd
, len
);
267 if (tcd
->tcd_cur_pages
> 0) {
268 tage
= cfs_tage_from_list(tcd
->tcd_pages
.next
);
270 cfs_tage_to_tail(tage
, &tcd
->tcd_pages
);
275 int libcfs_debug_msg(struct libcfs_debug_msg_data
*msgdata
,
276 const char *format
, ...)
281 va_start(args
, format
);
282 rc
= libcfs_debug_vmsg2(msgdata
, format
, args
, NULL
);
287 EXPORT_SYMBOL(libcfs_debug_msg
);
289 int libcfs_debug_vmsg2(struct libcfs_debug_msg_data
*msgdata
,
290 const char *format1
, va_list args
,
291 const char *format2
, ...)
293 struct cfs_trace_cpu_data
*tcd
= NULL
;
294 struct ptldebug_header header
= { 0 };
295 struct cfs_trace_page
*tage
;
296 /* string_buf is used only if tcd != NULL, and is always set then */
297 char *string_buf
= NULL
;
300 int needed
= 85; /* average message length */
306 int mask
= msgdata
->msg_mask
;
307 const char *file
= kbasename(msgdata
->msg_file
);
308 struct cfs_debug_limit_state
*cdls
= msgdata
->msg_cdls
;
310 tcd
= cfs_trace_get_tcd();
312 /* cfs_trace_get_tcd() grabs a lock, which disables preemption and
313 * pins us to a particular CPU. This avoids an smp_processor_id()
314 * warning on Linux when debugging is enabled.
316 cfs_set_ptldebug_header(&header
, msgdata
, CDEBUG_STACK());
318 if (!tcd
) /* arch may not log in IRQ context */
321 if (!tcd
->tcd_cur_pages
)
322 header
.ph_flags
|= PH_FLAG_FIRST_RECORD
;
324 if (tcd
->tcd_shutting_down
) {
325 cfs_trace_put_tcd(tcd
);
330 depth
= __current_nesting_level();
331 known_size
= strlen(file
) + 1 + depth
;
333 known_size
+= strlen(msgdata
->msg_fn
) + 1;
335 if (libcfs_debug_binary
)
336 known_size
+= sizeof(header
);
339 * '2' used because vsnprintf return real size required for output
340 * _without_ terminating NULL.
341 * if needed is to small for this format.
343 for (i
= 0; i
< 2; i
++) {
344 tage
= cfs_trace_get_tage(tcd
, needed
+ known_size
+ 1);
346 if (needed
+ known_size
> PAGE_SIZE
)
349 cfs_trace_put_tcd(tcd
);
354 string_buf
= (char *)page_address(tage
->page
) +
355 tage
->used
+ known_size
;
357 max_nob
= PAGE_SIZE
- tage
->used
- known_size
;
359 pr_emerg("negative max_nob: %d\n", max_nob
);
361 cfs_trace_put_tcd(tcd
);
369 needed
= vsnprintf(string_buf
, max_nob
, format1
, ap
);
374 remain
= max_nob
- needed
;
378 va_start(ap
, format2
);
379 needed
+= vsnprintf(string_buf
+ needed
, remain
,
384 if (needed
< max_nob
) /* well. printing ok.. */
388 if (*(string_buf
+ needed
- 1) != '\n')
389 pr_info("format at %s:%d:%s doesn't end in newline\n", file
,
390 msgdata
->msg_line
, msgdata
->msg_fn
);
392 header
.ph_len
= known_size
+ needed
;
393 debug_buf
= (char *)page_address(tage
->page
) + tage
->used
;
395 if (libcfs_debug_binary
) {
396 memcpy(debug_buf
, &header
, sizeof(header
));
397 tage
->used
+= sizeof(header
);
398 debug_buf
+= sizeof(header
);
401 /* indent message according to the nesting level */
402 while (depth
-- > 0) {
403 *(debug_buf
++) = '.';
407 strcpy(debug_buf
, file
);
408 tage
->used
+= strlen(file
) + 1;
409 debug_buf
+= strlen(file
) + 1;
411 if (msgdata
->msg_fn
) {
412 strcpy(debug_buf
, msgdata
->msg_fn
);
413 tage
->used
+= strlen(msgdata
->msg_fn
) + 1;
414 debug_buf
+= strlen(msgdata
->msg_fn
) + 1;
417 __LASSERT(debug_buf
== string_buf
);
419 tage
->used
+= needed
;
420 __LASSERT(tage
->used
<= PAGE_SIZE
);
423 if (!(mask
& libcfs_printk
)) {
424 /* no console output requested */
426 cfs_trace_put_tcd(tcd
);
431 if (libcfs_console_ratelimit
&&
432 cdls
->cdls_next
&& /* not first time ever */
433 !cfs_time_after(cfs_time_current(), cdls
->cdls_next
)) {
434 /* skipping a console message */
437 cfs_trace_put_tcd(tcd
);
441 if (cfs_time_after(cfs_time_current(),
442 cdls
->cdls_next
+ libcfs_console_max_delay
+
443 cfs_time_seconds(10))) {
444 /* last timeout was a long time ago */
445 cdls
->cdls_delay
/= libcfs_console_backoff
* 4;
447 cdls
->cdls_delay
*= libcfs_console_backoff
;
450 if (cdls
->cdls_delay
< libcfs_console_min_delay
)
451 cdls
->cdls_delay
= libcfs_console_min_delay
;
452 else if (cdls
->cdls_delay
> libcfs_console_max_delay
)
453 cdls
->cdls_delay
= libcfs_console_max_delay
;
455 /* ensure cdls_next is never zero after it's been seen */
456 cdls
->cdls_next
= (cfs_time_current() + cdls
->cdls_delay
) | 1;
460 cfs_print_to_console(&header
, mask
, string_buf
, needed
, file
,
462 cfs_trace_put_tcd(tcd
);
464 string_buf
= cfs_trace_get_console_buffer();
469 needed
= vsnprintf(string_buf
,
470 CFS_TRACE_CONSOLE_BUFFER_SIZE
,
475 remain
= CFS_TRACE_CONSOLE_BUFFER_SIZE
- needed
;
477 va_start(ap
, format2
);
478 needed
+= vsnprintf(string_buf
+ needed
, remain
,
483 cfs_print_to_console(&header
, mask
,
484 string_buf
, needed
, file
, msgdata
->msg_fn
);
489 if (cdls
&& cdls
->cdls_count
) {
490 string_buf
= cfs_trace_get_console_buffer();
492 needed
= snprintf(string_buf
, CFS_TRACE_CONSOLE_BUFFER_SIZE
,
493 "Skipped %d previous similar message%s\n",
495 (cdls
->cdls_count
> 1) ? "s" : "");
497 cfs_print_to_console(&header
, mask
,
498 string_buf
, needed
, file
, msgdata
->msg_fn
);
501 cdls
->cdls_count
= 0;
506 EXPORT_SYMBOL(libcfs_debug_vmsg2
);
509 cfs_trace_assertion_failed(const char *str
,
510 struct libcfs_debug_msg_data
*msgdata
)
512 struct ptldebug_header hdr
;
514 libcfs_panic_in_progress
= 1;
515 libcfs_catastrophe
= 1;
518 cfs_set_ptldebug_header(&hdr
, msgdata
, CDEBUG_STACK());
520 cfs_print_to_console(&hdr
, D_EMERG
, str
, strlen(str
),
521 msgdata
->msg_file
, msgdata
->msg_fn
);
523 panic("Lustre debug assertion failure\n");
529 panic_collect_pages(struct page_collection
*pc
)
531 /* Do the collect_pages job on a single CPU: assumes that all other
532 * CPUs have been stopped during a panic. If this isn't true for some
533 * arch, this will have to be implemented separately in each arch.
535 struct cfs_trace_cpu_data
*tcd
;
539 INIT_LIST_HEAD(&pc
->pc_pages
);
541 cfs_tcd_for_each(tcd
, i
, j
) {
542 list_splice_init(&tcd
->tcd_pages
, &pc
->pc_pages
);
543 tcd
->tcd_cur_pages
= 0;
545 if (pc
->pc_want_daemon_pages
) {
546 list_splice_init(&tcd
->tcd_daemon_pages
, &pc
->pc_pages
);
547 tcd
->tcd_cur_daemon_pages
= 0;
552 static void collect_pages_on_all_cpus(struct page_collection
*pc
)
554 struct cfs_trace_cpu_data
*tcd
;
557 for_each_possible_cpu(cpu
) {
558 cfs_tcd_for_each_type_lock(tcd
, i
, cpu
) {
559 list_splice_init(&tcd
->tcd_pages
, &pc
->pc_pages
);
560 tcd
->tcd_cur_pages
= 0;
561 if (pc
->pc_want_daemon_pages
) {
562 list_splice_init(&tcd
->tcd_daemon_pages
,
564 tcd
->tcd_cur_daemon_pages
= 0;
570 static void collect_pages(struct page_collection
*pc
)
572 INIT_LIST_HEAD(&pc
->pc_pages
);
574 if (libcfs_panic_in_progress
)
575 panic_collect_pages(pc
);
577 collect_pages_on_all_cpus(pc
);
580 static void put_pages_back_on_all_cpus(struct page_collection
*pc
)
582 struct cfs_trace_cpu_data
*tcd
;
583 struct list_head
*cur_head
;
584 struct cfs_trace_page
*tage
;
585 struct cfs_trace_page
*tmp
;
588 for_each_possible_cpu(cpu
) {
589 cfs_tcd_for_each_type_lock(tcd
, i
, cpu
) {
590 cur_head
= tcd
->tcd_pages
.next
;
592 list_for_each_entry_safe(tage
, tmp
, &pc
->pc_pages
,
594 __LASSERT_TAGE_INVARIANT(tage
);
596 if (tage
->cpu
!= cpu
|| tage
->type
!= i
)
599 cfs_tage_to_tail(tage
, cur_head
);
600 tcd
->tcd_cur_pages
++;
606 static void put_pages_back(struct page_collection
*pc
)
608 if (!libcfs_panic_in_progress
)
609 put_pages_back_on_all_cpus(pc
);
612 /* Add pages to a per-cpu debug daemon ringbuffer. This buffer makes sure that
613 * we have a good amount of data at all times for dumping during an LBUG, even
614 * if we have been steadily writing (and otherwise discarding) pages via the
617 static void put_pages_on_tcd_daemon_list(struct page_collection
*pc
,
618 struct cfs_trace_cpu_data
*tcd
)
620 struct cfs_trace_page
*tage
;
621 struct cfs_trace_page
*tmp
;
623 list_for_each_entry_safe(tage
, tmp
, &pc
->pc_pages
, linkage
) {
624 __LASSERT_TAGE_INVARIANT(tage
);
626 if (tage
->cpu
!= tcd
->tcd_cpu
|| tage
->type
!= tcd
->tcd_type
)
629 cfs_tage_to_tail(tage
, &tcd
->tcd_daemon_pages
);
630 tcd
->tcd_cur_daemon_pages
++;
632 if (tcd
->tcd_cur_daemon_pages
> tcd
->tcd_max_pages
) {
633 struct cfs_trace_page
*victim
;
635 __LASSERT(!list_empty(&tcd
->tcd_daemon_pages
));
636 victim
= cfs_tage_from_list(tcd
->tcd_daemon_pages
.next
);
638 __LASSERT_TAGE_INVARIANT(victim
);
640 list_del(&victim
->linkage
);
641 cfs_tage_free(victim
);
642 tcd
->tcd_cur_daemon_pages
--;
647 static void put_pages_on_daemon_list(struct page_collection
*pc
)
649 struct cfs_trace_cpu_data
*tcd
;
652 for_each_possible_cpu(cpu
) {
653 cfs_tcd_for_each_type_lock(tcd
, i
, cpu
)
654 put_pages_on_tcd_daemon_list(pc
, tcd
);
658 void cfs_trace_debug_print(void)
660 struct page_collection pc
;
661 struct cfs_trace_page
*tage
;
662 struct cfs_trace_page
*tmp
;
664 pc
.pc_want_daemon_pages
= 1;
666 list_for_each_entry_safe(tage
, tmp
, &pc
.pc_pages
, linkage
) {
670 __LASSERT_TAGE_INVARIANT(tage
);
673 p
= page_address(page
);
674 while (p
< ((char *)page_address(page
) + tage
->used
)) {
675 struct ptldebug_header
*hdr
;
681 p
+= strlen(file
) + 1;
684 len
= hdr
->ph_len
- (int)(p
- (char *)hdr
);
686 cfs_print_to_console(hdr
, D_EMERG
, p
, len
, file
, fn
);
691 list_del(&tage
->linkage
);
696 int cfs_tracefile_dump_all_pages(char *filename
)
698 struct page_collection pc
;
700 struct cfs_trace_page
*tage
;
701 struct cfs_trace_page
*tmp
;
703 mm_segment_t __oldfs
;
706 cfs_tracefile_write_lock();
708 filp
= filp_open(filename
, O_CREAT
| O_EXCL
| O_WRONLY
| O_LARGEFILE
,
713 pr_err("LustreError: can't open %s for dump: rc %d\n",
718 pc
.pc_want_daemon_pages
= 1;
720 if (list_empty(&pc
.pc_pages
)) {
727 /* ok, for now, just write the pages. in the future we'll be building
728 * iobufs with the pages and calling generic_direct_IO
730 list_for_each_entry_safe(tage
, tmp
, &pc
.pc_pages
, linkage
) {
731 __LASSERT_TAGE_INVARIANT(tage
);
733 buf
= kmap(tage
->page
);
734 rc
= kernel_write(filp
, buf
, tage
->used
, &filp
->f_pos
);
737 if (rc
!= (int)tage
->used
) {
738 pr_warn("wanted to write %u but wrote %d\n", tage
->used
,
741 __LASSERT(list_empty(&pc
.pc_pages
));
744 list_del(&tage
->linkage
);
748 rc
= vfs_fsync(filp
, 1);
750 pr_err("sync returns %d\n", rc
);
752 filp_close(filp
, NULL
);
754 cfs_tracefile_write_unlock();
758 void cfs_trace_flush_pages(void)
760 struct page_collection pc
;
761 struct cfs_trace_page
*tage
;
762 struct cfs_trace_page
*tmp
;
764 pc
.pc_want_daemon_pages
= 1;
766 list_for_each_entry_safe(tage
, tmp
, &pc
.pc_pages
, linkage
) {
767 __LASSERT_TAGE_INVARIANT(tage
);
769 list_del(&tage
->linkage
);
774 int cfs_trace_copyin_string(char *knl_buffer
, int knl_buffer_nob
,
775 const char __user
*usr_buffer
, int usr_buffer_nob
)
779 if (usr_buffer_nob
> knl_buffer_nob
)
782 if (copy_from_user((void *)knl_buffer
,
783 usr_buffer
, usr_buffer_nob
))
786 nob
= strnlen(knl_buffer
, usr_buffer_nob
);
787 while (nob
-- >= 0) /* strip trailing whitespace */
788 if (!isspace(knl_buffer
[nob
]))
791 if (nob
< 0) /* empty string */
794 if (nob
== knl_buffer_nob
) /* no space to terminate */
797 knl_buffer
[nob
+ 1] = 0; /* terminate */
800 EXPORT_SYMBOL(cfs_trace_copyin_string
);
802 int cfs_trace_copyout_string(char __user
*usr_buffer
, int usr_buffer_nob
,
803 const char *knl_buffer
, char *append
)
806 * NB if 'append' != NULL, it's a single character to append to the
807 * copied out string - usually "\n" or "" (i.e. a terminating zero byte)
809 int nob
= strlen(knl_buffer
);
811 if (nob
> usr_buffer_nob
)
812 nob
= usr_buffer_nob
;
814 if (copy_to_user(usr_buffer
, knl_buffer
, nob
))
817 if (append
&& nob
< usr_buffer_nob
) {
818 if (copy_to_user(usr_buffer
+ nob
, append
, 1))
826 EXPORT_SYMBOL(cfs_trace_copyout_string
);
828 int cfs_trace_allocate_string_buffer(char **str
, int nob
)
830 if (nob
> 2 * PAGE_SIZE
) /* string must be "sensible" */
833 *str
= kmalloc(nob
, GFP_KERNEL
| __GFP_ZERO
);
840 int cfs_trace_dump_debug_buffer_usrstr(void __user
*usr_str
, int usr_str_nob
)
845 rc
= cfs_trace_allocate_string_buffer(&str
, usr_str_nob
+ 1);
849 rc
= cfs_trace_copyin_string(str
, usr_str_nob
+ 1,
850 usr_str
, usr_str_nob
);
858 rc
= cfs_tracefile_dump_all_pages(str
);
864 int cfs_trace_daemon_command(char *str
)
868 cfs_tracefile_write_lock();
870 if (!strcmp(str
, "stop")) {
871 cfs_tracefile_write_unlock();
872 cfs_trace_stop_thread();
873 cfs_tracefile_write_lock();
874 memset(cfs_tracefile
, 0, sizeof(cfs_tracefile
));
876 } else if (!strncmp(str
, "size=", 5)) {
879 rc
= kstrtoul(str
+ 5, 10, &tmp
);
881 if (tmp
< 10 || tmp
> 20480)
882 cfs_tracefile_size
= CFS_TRACEFILE_SIZE
;
884 cfs_tracefile_size
= tmp
<< 20;
886 } else if (strlen(str
) >= sizeof(cfs_tracefile
)) {
888 } else if (str
[0] != '/') {
891 strcpy(cfs_tracefile
, str
);
893 pr_info("debug daemon will attempt to start writing to %s (%lukB max)\n",
895 (long)(cfs_tracefile_size
>> 10));
897 cfs_trace_start_thread();
900 cfs_tracefile_write_unlock();
904 int cfs_trace_daemon_command_usrstr(void __user
*usr_str
, int usr_str_nob
)
909 rc
= cfs_trace_allocate_string_buffer(&str
, usr_str_nob
+ 1);
913 rc
= cfs_trace_copyin_string(str
, usr_str_nob
+ 1,
914 usr_str
, usr_str_nob
);
916 rc
= cfs_trace_daemon_command(str
);
922 int cfs_trace_set_debug_mb(int mb
)
927 int limit
= cfs_trace_max_debug_mb();
928 struct cfs_trace_cpu_data
*tcd
;
930 if (mb
< num_possible_cpus()) {
931 pr_warn("%d MB is too small for debug buffer size, setting it to %d MB.\n",
932 mb
, num_possible_cpus());
933 mb
= num_possible_cpus();
937 pr_warn("%d MB is too large for debug buffer size, setting it to %d MB.\n",
942 mb
/= num_possible_cpus();
943 pages
= mb
<< (20 - PAGE_SHIFT
);
945 cfs_tracefile_write_lock();
947 cfs_tcd_for_each(tcd
, i
, j
)
948 tcd
->tcd_max_pages
= (pages
* tcd
->tcd_pages_factor
) / 100;
950 cfs_tracefile_write_unlock();
955 int cfs_trace_get_debug_mb(void)
959 struct cfs_trace_cpu_data
*tcd
;
962 cfs_tracefile_read_lock();
964 cfs_tcd_for_each(tcd
, i
, j
)
965 total_pages
+= tcd
->tcd_max_pages
;
967 cfs_tracefile_read_unlock();
969 return (total_pages
>> (20 - PAGE_SHIFT
)) + 1;
972 static int tracefiled(void *arg
)
974 struct page_collection pc
;
975 struct tracefiled_ctl
*tctl
= arg
;
976 struct cfs_trace_page
*tage
;
977 struct cfs_trace_page
*tmp
;
983 /* we're started late enough that we pick up init's fs context */
984 /* this is so broken in uml? what on earth is going on? */
986 complete(&tctl
->tctl_start
);
989 wait_queue_entry_t __wait
;
991 pc
.pc_want_daemon_pages
= 0;
993 if (list_empty(&pc
.pc_pages
))
997 cfs_tracefile_read_lock();
998 if (cfs_tracefile
[0]) {
999 filp
= filp_open(cfs_tracefile
,
1000 O_CREAT
| O_RDWR
| O_LARGEFILE
,
1005 pr_warn("couldn't open %s: %d\n", cfs_tracefile
,
1009 cfs_tracefile_read_unlock();
1011 put_pages_on_daemon_list(&pc
);
1012 __LASSERT(list_empty(&pc
.pc_pages
));
1016 list_for_each_entry_safe(tage
, tmp
, &pc
.pc_pages
, linkage
) {
1017 static loff_t f_pos
;
1019 __LASSERT_TAGE_INVARIANT(tage
);
1021 if (f_pos
>= (off_t
)cfs_tracefile_size
)
1023 else if (f_pos
> i_size_read(file_inode(filp
)))
1024 f_pos
= i_size_read(file_inode(filp
));
1026 buf
= kmap(tage
->page
);
1027 rc
= kernel_write(filp
, buf
, tage
->used
, &f_pos
);
1030 if (rc
!= (int)tage
->used
) {
1031 pr_warn("wanted to write %u but wrote %d\n",
1033 put_pages_back(&pc
);
1034 __LASSERT(list_empty(&pc
.pc_pages
));
1039 filp_close(filp
, NULL
);
1040 put_pages_on_daemon_list(&pc
);
1041 if (!list_empty(&pc
.pc_pages
)) {
1044 pr_alert("trace pages aren't empty\n");
1045 pr_err("total cpus(%d): ", num_possible_cpus());
1046 for (i
= 0; i
< num_possible_cpus(); i
++)
1048 pr_cont("%d(on) ", i
);
1050 pr_cont("%d(off) ", i
);
1054 list_for_each_entry_safe(tage
, tmp
, &pc
.pc_pages
,
1056 pr_err("page %d belongs to cpu %d\n",
1058 pr_err("There are %d pages unwritten\n", i
);
1060 __LASSERT(list_empty(&pc
.pc_pages
));
1062 if (atomic_read(&tctl
->tctl_shutdown
)) {
1070 init_waitqueue_entry(&__wait
, current
);
1071 add_wait_queue(&tctl
->tctl_waitq
, &__wait
);
1072 set_current_state(TASK_INTERRUPTIBLE
);
1073 schedule_timeout(cfs_time_seconds(1));
1074 remove_wait_queue(&tctl
->tctl_waitq
, &__wait
);
1076 complete(&tctl
->tctl_stop
);
1080 int cfs_trace_start_thread(void)
1082 struct tracefiled_ctl
*tctl
= &trace_tctl
;
1083 struct task_struct
*task
;
1086 mutex_lock(&cfs_trace_thread_mutex
);
1090 init_completion(&tctl
->tctl_start
);
1091 init_completion(&tctl
->tctl_stop
);
1092 init_waitqueue_head(&tctl
->tctl_waitq
);
1093 atomic_set(&tctl
->tctl_shutdown
, 0);
1095 task
= kthread_run(tracefiled
, tctl
, "ktracefiled");
1101 wait_for_completion(&tctl
->tctl_start
);
1104 mutex_unlock(&cfs_trace_thread_mutex
);
1108 void cfs_trace_stop_thread(void)
1110 struct tracefiled_ctl
*tctl
= &trace_tctl
;
1112 mutex_lock(&cfs_trace_thread_mutex
);
1113 if (thread_running
) {
1114 pr_info("shutting down debug daemon thread...\n");
1115 atomic_set(&tctl
->tctl_shutdown
, 1);
1116 wait_for_completion(&tctl
->tctl_stop
);
1119 mutex_unlock(&cfs_trace_thread_mutex
);
1122 int cfs_tracefile_init(int max_pages
)
1124 struct cfs_trace_cpu_data
*tcd
;
1130 rc
= cfs_tracefile_init_arch();
1134 cfs_tcd_for_each(tcd
, i
, j
) {
1135 /* tcd_pages_factor is initialized int tracefile_init_arch. */
1136 factor
= tcd
->tcd_pages_factor
;
1137 INIT_LIST_HEAD(&tcd
->tcd_pages
);
1138 INIT_LIST_HEAD(&tcd
->tcd_stock_pages
);
1139 INIT_LIST_HEAD(&tcd
->tcd_daemon_pages
);
1140 tcd
->tcd_cur_pages
= 0;
1141 tcd
->tcd_cur_stock_pages
= 0;
1142 tcd
->tcd_cur_daemon_pages
= 0;
1143 tcd
->tcd_max_pages
= (max_pages
* factor
) / 100;
1144 LASSERT(tcd
->tcd_max_pages
> 0);
1145 tcd
->tcd_shutting_down
= 0;
1151 static void trace_cleanup_on_all_cpus(void)
1153 struct cfs_trace_cpu_data
*tcd
;
1154 struct cfs_trace_page
*tage
;
1155 struct cfs_trace_page
*tmp
;
1158 for_each_possible_cpu(cpu
) {
1159 cfs_tcd_for_each_type_lock(tcd
, i
, cpu
) {
1160 tcd
->tcd_shutting_down
= 1;
1162 list_for_each_entry_safe(tage
, tmp
, &tcd
->tcd_pages
,
1164 __LASSERT_TAGE_INVARIANT(tage
);
1166 list_del(&tage
->linkage
);
1167 cfs_tage_free(tage
);
1170 tcd
->tcd_cur_pages
= 0;
1175 static void cfs_trace_cleanup(void)
1177 struct page_collection pc
;
1179 INIT_LIST_HEAD(&pc
.pc_pages
);
1181 trace_cleanup_on_all_cpus();
1183 cfs_tracefile_fini_arch();
1186 void cfs_tracefile_exit(void)
1188 cfs_trace_stop_thread();
1189 cfs_trace_cleanup();