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.sun.com/software/products/lustre/docs/GPLv2.pdf
20 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
21 * CA 95054 USA or visit www.sun.com if you need additional information or
27 * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
28 * Use is subject to license terms.
30 * Copyright (c) 2012, Intel Corporation.
33 * This file is part of Lustre, http://www.lustre.org/
34 * Lustre is a trademark of Sun Microsystems, Inc.
36 * libcfs/libcfs/tracefile.c
38 * Author: Zach Brown <zab@clusterfs.com>
39 * Author: Phil Schwan <phil@clusterfs.com>
43 #define DEBUG_SUBSYSTEM S_LNET
44 #define LUSTRE_TRACEFILE_PRIVATE
45 #include "tracefile.h"
47 #include "../../include/linux/libcfs/libcfs.h"
49 /* XXX move things up to the top, comment */
50 union cfs_trace_data_union (*cfs_trace_data[TCD_MAX_TYPES])[NR_CPUS] __cacheline_aligned;
52 char cfs_tracefile[TRACEFILE_NAME_SIZE];
53 long long cfs_tracefile_size = CFS_TRACEFILE_SIZE;
54 static struct tracefiled_ctl trace_tctl;
55 struct mutex cfs_trace_thread_mutex;
56 static int thread_running = 0;
58 atomic_t cfs_tage_allocated = ATOMIC_INIT(0);
60 static void put_pages_on_tcd_daemon_list(struct page_collection *pc,
61 struct cfs_trace_cpu_data *tcd);
63 static inline struct cfs_trace_page *
64 cfs_tage_from_list(struct list_head *list)
66 return list_entry(list, struct cfs_trace_page, linkage);
69 static struct cfs_trace_page *cfs_tage_alloc(gfp_t gfp)
72 struct cfs_trace_page *tage;
74 /* My caller is trying to free memory */
75 if (!in_interrupt() && memory_pressure_get())
79 * Don't spam console with allocation failures: they will be reported
80 * by upper layer anyway.
83 page = alloc_page(gfp);
87 tage = kmalloc(sizeof(*tage), gfp);
94 atomic_inc(&cfs_tage_allocated);
98 static void cfs_tage_free(struct cfs_trace_page *tage)
100 __LASSERT(tage != NULL);
101 __LASSERT(tage->page != NULL);
103 __free_page(tage->page);
105 atomic_dec(&cfs_tage_allocated);
108 static void cfs_tage_to_tail(struct cfs_trace_page *tage,
109 struct list_head *queue)
111 __LASSERT(tage != NULL);
112 __LASSERT(queue != NULL);
114 list_move_tail(&tage->linkage, queue);
117 int cfs_trace_refill_stock(struct cfs_trace_cpu_data *tcd, gfp_t gfp,
118 struct list_head *stock)
123 * XXX nikita: do NOT call portals_debug_msg() (CDEBUG/ENTRY/EXIT)
124 * from here: this will lead to infinite recursion.
127 for (i = 0; i + tcd->tcd_cur_stock_pages < TCD_STOCK_PAGES ; ++ i) {
128 struct cfs_trace_page *tage;
130 tage = cfs_tage_alloc(gfp);
133 list_add_tail(&tage->linkage, stock);
138 /* return a page that has 'len' bytes left at the end */
139 static struct cfs_trace_page *
140 cfs_trace_get_tage_try(struct cfs_trace_cpu_data *tcd, unsigned long len)
142 struct cfs_trace_page *tage;
144 if (tcd->tcd_cur_pages > 0) {
145 __LASSERT(!list_empty(&tcd->tcd_pages));
146 tage = cfs_tage_from_list(tcd->tcd_pages.prev);
147 if (tage->used + len <= PAGE_CACHE_SIZE)
151 if (tcd->tcd_cur_pages < tcd->tcd_max_pages) {
152 if (tcd->tcd_cur_stock_pages > 0) {
153 tage = cfs_tage_from_list(tcd->tcd_stock_pages.prev);
154 --tcd->tcd_cur_stock_pages;
155 list_del_init(&tage->linkage);
157 tage = cfs_tage_alloc(GFP_ATOMIC);
158 if (unlikely(tage == NULL)) {
159 if ((!memory_pressure_get() ||
160 in_interrupt()) && printk_ratelimit())
162 "cannot allocate a tage (%ld)\n",
169 tage->cpu = smp_processor_id();
170 tage->type = tcd->tcd_type;
171 list_add_tail(&tage->linkage, &tcd->tcd_pages);
172 tcd->tcd_cur_pages++;
174 if (tcd->tcd_cur_pages > 8 && thread_running) {
175 struct tracefiled_ctl *tctl = &trace_tctl;
177 * wake up tracefiled to process some pages.
179 wake_up(&tctl->tctl_waitq);
186 static void cfs_tcd_shrink(struct cfs_trace_cpu_data *tcd)
188 int pgcount = tcd->tcd_cur_pages / 10;
189 struct page_collection pc;
190 struct cfs_trace_page *tage;
191 struct cfs_trace_page *tmp;
194 * XXX nikita: do NOT call portals_debug_msg() (CDEBUG/ENTRY/EXIT)
195 * from here: this will lead to infinite recursion.
198 if (printk_ratelimit())
199 printk(KERN_WARNING "debug daemon buffer overflowed; "
200 "discarding 10%% of pages (%d of %ld)\n",
201 pgcount + 1, tcd->tcd_cur_pages);
203 INIT_LIST_HEAD(&pc.pc_pages);
204 spin_lock_init(&pc.pc_lock);
206 list_for_each_entry_safe(tage, tmp, &tcd->tcd_pages, linkage) {
210 list_move_tail(&tage->linkage, &pc.pc_pages);
211 tcd->tcd_cur_pages--;
213 put_pages_on_tcd_daemon_list(&pc, tcd);
216 /* return a page that has 'len' bytes left at the end */
217 static struct cfs_trace_page *cfs_trace_get_tage(struct cfs_trace_cpu_data *tcd,
220 struct cfs_trace_page *tage;
223 * XXX nikita: do NOT call portals_debug_msg() (CDEBUG/ENTRY/EXIT)
224 * from here: this will lead to infinite recursion.
227 if (len > PAGE_CACHE_SIZE) {
229 "cowardly refusing to write %lu bytes in a page\n", len);
233 tage = cfs_trace_get_tage_try(tcd, len);
238 if (tcd->tcd_cur_pages > 0) {
239 tage = cfs_tage_from_list(tcd->tcd_pages.next);
241 cfs_tage_to_tail(tage, &tcd->tcd_pages);
246 int libcfs_debug_msg(struct libcfs_debug_msg_data *msgdata,
247 const char *format, ...)
252 va_start(args, format);
253 rc = libcfs_debug_vmsg2(msgdata, format, args, NULL);
258 EXPORT_SYMBOL(libcfs_debug_msg);
260 int libcfs_debug_vmsg2(struct libcfs_debug_msg_data *msgdata,
261 const char *format1, va_list args,
262 const char *format2, ...)
264 struct cfs_trace_cpu_data *tcd = NULL;
265 struct ptldebug_header header = {0};
266 struct cfs_trace_page *tage;
267 /* string_buf is used only if tcd != NULL, and is always set then */
268 char *string_buf = NULL;
271 int needed = 85; /* average message length */
277 int mask = msgdata->msg_mask;
278 const char *file = kbasename(msgdata->msg_file);
279 struct cfs_debug_limit_state *cdls = msgdata->msg_cdls;
281 tcd = cfs_trace_get_tcd();
283 /* cfs_trace_get_tcd() grabs a lock, which disables preemption and
284 * pins us to a particular CPU. This avoids an smp_processor_id()
285 * warning on Linux when debugging is enabled. */
286 cfs_set_ptldebug_header(&header, msgdata, CDEBUG_STACK());
288 if (tcd == NULL) /* arch may not log in IRQ context */
291 if (tcd->tcd_cur_pages == 0)
292 header.ph_flags |= PH_FLAG_FIRST_RECORD;
294 if (tcd->tcd_shutting_down) {
295 cfs_trace_put_tcd(tcd);
300 depth = __current_nesting_level();
301 known_size = strlen(file) + 1 + depth;
303 known_size += strlen(msgdata->msg_fn) + 1;
305 if (libcfs_debug_binary)
306 known_size += sizeof(header);
309 * '2' used because vsnprintf return real size required for output
310 * _without_ terminating NULL.
311 * if needed is to small for this format.
313 for (i = 0; i < 2; i++) {
314 tage = cfs_trace_get_tage(tcd, needed + known_size + 1);
316 if (needed + known_size > PAGE_CACHE_SIZE)
319 cfs_trace_put_tcd(tcd);
324 string_buf = (char *)page_address(tage->page) +
325 tage->used + known_size;
327 max_nob = PAGE_CACHE_SIZE - tage->used - known_size;
329 printk(KERN_EMERG "negative max_nob: %d\n",
332 cfs_trace_put_tcd(tcd);
340 needed = vsnprintf(string_buf, max_nob, format1, ap);
345 remain = max_nob - needed;
349 va_start(ap, format2);
350 needed += vsnprintf(string_buf + needed, remain,
355 if (needed < max_nob) /* well. printing ok.. */
359 if (*(string_buf+needed-1) != '\n')
360 printk(KERN_INFO "format at %s:%d:%s doesn't end in "
361 "newline\n", file, msgdata->msg_line, msgdata->msg_fn);
363 header.ph_len = known_size + needed;
364 debug_buf = (char *)page_address(tage->page) + tage->used;
366 if (libcfs_debug_binary) {
367 memcpy(debug_buf, &header, sizeof(header));
368 tage->used += sizeof(header);
369 debug_buf += sizeof(header);
372 /* indent message according to the nesting level */
373 while (depth-- > 0) {
374 *(debug_buf++) = '.';
378 strcpy(debug_buf, file);
379 tage->used += strlen(file) + 1;
380 debug_buf += strlen(file) + 1;
382 if (msgdata->msg_fn) {
383 strcpy(debug_buf, msgdata->msg_fn);
384 tage->used += strlen(msgdata->msg_fn) + 1;
385 debug_buf += strlen(msgdata->msg_fn) + 1;
388 __LASSERT(debug_buf == string_buf);
390 tage->used += needed;
391 __LASSERT (tage->used <= PAGE_CACHE_SIZE);
394 if ((mask & libcfs_printk) == 0) {
395 /* no console output requested */
397 cfs_trace_put_tcd(tcd);
402 if (libcfs_console_ratelimit &&
403 cdls->cdls_next != 0 && /* not first time ever */
404 !cfs_time_after(cfs_time_current(), cdls->cdls_next)) {
405 /* skipping a console message */
408 cfs_trace_put_tcd(tcd);
412 if (cfs_time_after(cfs_time_current(), cdls->cdls_next +
413 libcfs_console_max_delay
414 + cfs_time_seconds(10))) {
415 /* last timeout was a long time ago */
416 cdls->cdls_delay /= libcfs_console_backoff * 4;
418 cdls->cdls_delay *= libcfs_console_backoff;
421 if (cdls->cdls_delay < libcfs_console_min_delay)
422 cdls->cdls_delay = libcfs_console_min_delay;
423 else if (cdls->cdls_delay > libcfs_console_max_delay)
424 cdls->cdls_delay = libcfs_console_max_delay;
426 /* ensure cdls_next is never zero after it's been seen */
427 cdls->cdls_next = (cfs_time_current() + cdls->cdls_delay) | 1;
431 cfs_print_to_console(&header, mask, string_buf, needed, file,
433 cfs_trace_put_tcd(tcd);
435 string_buf = cfs_trace_get_console_buffer();
438 if (format1 != NULL) {
440 needed = vsnprintf(string_buf,
441 CFS_TRACE_CONSOLE_BUFFER_SIZE,
445 if (format2 != NULL) {
446 remain = CFS_TRACE_CONSOLE_BUFFER_SIZE - needed;
448 va_start(ap, format2);
449 needed += vsnprintf(string_buf+needed, remain,
454 cfs_print_to_console(&header, mask,
455 string_buf, needed, file, msgdata->msg_fn);
457 cfs_trace_put_console_buffer(string_buf);
460 if (cdls != NULL && cdls->cdls_count != 0) {
461 string_buf = cfs_trace_get_console_buffer();
463 needed = snprintf(string_buf, CFS_TRACE_CONSOLE_BUFFER_SIZE,
464 "Skipped %d previous similar message%s\n",
466 (cdls->cdls_count > 1) ? "s" : "");
468 cfs_print_to_console(&header, mask,
469 string_buf, needed, file, msgdata->msg_fn);
471 cfs_trace_put_console_buffer(string_buf);
472 cdls->cdls_count = 0;
477 EXPORT_SYMBOL(libcfs_debug_vmsg2);
480 cfs_trace_assertion_failed(const char *str,
481 struct libcfs_debug_msg_data *msgdata)
483 struct ptldebug_header hdr;
485 libcfs_panic_in_progress = 1;
486 libcfs_catastrophe = 1;
489 cfs_set_ptldebug_header(&hdr, msgdata, CDEBUG_STACK());
491 cfs_print_to_console(&hdr, D_EMERG, str, strlen(str),
492 msgdata->msg_file, msgdata->msg_fn);
494 panic("Lustre debug assertion failure\n");
500 panic_collect_pages(struct page_collection *pc)
502 /* Do the collect_pages job on a single CPU: assumes that all other
503 * CPUs have been stopped during a panic. If this isn't true for some
504 * arch, this will have to be implemented separately in each arch. */
507 struct cfs_trace_cpu_data *tcd;
509 INIT_LIST_HEAD(&pc->pc_pages);
511 cfs_tcd_for_each(tcd, i, j) {
512 list_splice_init(&tcd->tcd_pages, &pc->pc_pages);
513 tcd->tcd_cur_pages = 0;
515 if (pc->pc_want_daemon_pages) {
516 list_splice_init(&tcd->tcd_daemon_pages,
518 tcd->tcd_cur_daemon_pages = 0;
523 static void collect_pages_on_all_cpus(struct page_collection *pc)
525 struct cfs_trace_cpu_data *tcd;
528 spin_lock(&pc->pc_lock);
529 for_each_possible_cpu(cpu) {
530 cfs_tcd_for_each_type_lock(tcd, i, cpu) {
531 list_splice_init(&tcd->tcd_pages, &pc->pc_pages);
532 tcd->tcd_cur_pages = 0;
533 if (pc->pc_want_daemon_pages) {
534 list_splice_init(&tcd->tcd_daemon_pages,
536 tcd->tcd_cur_daemon_pages = 0;
540 spin_unlock(&pc->pc_lock);
543 static void collect_pages(struct page_collection *pc)
545 INIT_LIST_HEAD(&pc->pc_pages);
547 if (libcfs_panic_in_progress)
548 panic_collect_pages(pc);
550 collect_pages_on_all_cpus(pc);
553 static void put_pages_back_on_all_cpus(struct page_collection *pc)
555 struct cfs_trace_cpu_data *tcd;
556 struct list_head *cur_head;
557 struct cfs_trace_page *tage;
558 struct cfs_trace_page *tmp;
561 spin_lock(&pc->pc_lock);
562 for_each_possible_cpu(cpu) {
563 cfs_tcd_for_each_type_lock(tcd, i, cpu) {
564 cur_head = tcd->tcd_pages.next;
566 list_for_each_entry_safe(tage, tmp, &pc->pc_pages,
569 __LASSERT_TAGE_INVARIANT(tage);
571 if (tage->cpu != cpu || tage->type != i)
574 cfs_tage_to_tail(tage, cur_head);
575 tcd->tcd_cur_pages++;
579 spin_unlock(&pc->pc_lock);
582 static void put_pages_back(struct page_collection *pc)
584 if (!libcfs_panic_in_progress)
585 put_pages_back_on_all_cpus(pc);
588 /* Add pages to a per-cpu debug daemon ringbuffer. This buffer makes sure that
589 * we have a good amount of data at all times for dumping during an LBUG, even
590 * if we have been steadily writing (and otherwise discarding) pages via the
592 static void put_pages_on_tcd_daemon_list(struct page_collection *pc,
593 struct cfs_trace_cpu_data *tcd)
595 struct cfs_trace_page *tage;
596 struct cfs_trace_page *tmp;
598 spin_lock(&pc->pc_lock);
599 list_for_each_entry_safe(tage, tmp, &pc->pc_pages, linkage) {
601 __LASSERT_TAGE_INVARIANT(tage);
603 if (tage->cpu != tcd->tcd_cpu || tage->type != tcd->tcd_type)
606 cfs_tage_to_tail(tage, &tcd->tcd_daemon_pages);
607 tcd->tcd_cur_daemon_pages++;
609 if (tcd->tcd_cur_daemon_pages > tcd->tcd_max_pages) {
610 struct cfs_trace_page *victim;
612 __LASSERT(!list_empty(&tcd->tcd_daemon_pages));
613 victim = cfs_tage_from_list(tcd->tcd_daemon_pages.next);
615 __LASSERT_TAGE_INVARIANT(victim);
617 list_del(&victim->linkage);
618 cfs_tage_free(victim);
619 tcd->tcd_cur_daemon_pages--;
622 spin_unlock(&pc->pc_lock);
625 static void put_pages_on_daemon_list(struct page_collection *pc)
627 struct cfs_trace_cpu_data *tcd;
630 for_each_possible_cpu(cpu) {
631 cfs_tcd_for_each_type_lock(tcd, i, cpu)
632 put_pages_on_tcd_daemon_list(pc, tcd);
636 void cfs_trace_debug_print(void)
638 struct page_collection pc;
639 struct cfs_trace_page *tage;
640 struct cfs_trace_page *tmp;
642 spin_lock_init(&pc.pc_lock);
644 pc.pc_want_daemon_pages = 1;
646 list_for_each_entry_safe(tage, tmp, &pc.pc_pages, linkage) {
650 __LASSERT_TAGE_INVARIANT(tage);
653 p = page_address(page);
654 while (p < ((char *)page_address(page) + tage->used)) {
655 struct ptldebug_header *hdr;
660 p += strlen(file) + 1;
663 len = hdr->ph_len - (int)(p - (char *)hdr);
665 cfs_print_to_console(hdr, D_EMERG, p, len, file, fn);
670 list_del(&tage->linkage);
675 int cfs_tracefile_dump_all_pages(char *filename)
677 struct page_collection pc;
679 struct cfs_trace_page *tage;
680 struct cfs_trace_page *tmp;
686 cfs_tracefile_write_lock();
688 filp = filp_open(filename, O_CREAT|O_EXCL|O_WRONLY|O_LARGEFILE, 0600);
692 printk(KERN_ERR "LustreError: can't open %s for dump: rc %d\n",
697 spin_lock_init(&pc.pc_lock);
698 pc.pc_want_daemon_pages = 1;
700 if (list_empty(&pc.pc_pages)) {
705 /* ok, for now, just write the pages. in the future we'll be building
706 * iobufs with the pages and calling generic_direct_IO */
708 list_for_each_entry_safe(tage, tmp, &pc.pc_pages, linkage) {
710 __LASSERT_TAGE_INVARIANT(tage);
712 buf = kmap(tage->page);
713 rc = vfs_write(filp, (__force const char __user *)buf,
714 tage->used, &filp->f_pos);
717 if (rc != (int)tage->used) {
718 printk(KERN_WARNING "wanted to write %u but wrote "
719 "%d\n", tage->used, rc);
721 __LASSERT(list_empty(&pc.pc_pages));
724 list_del(&tage->linkage);
728 rc = vfs_fsync(filp, 1);
730 printk(KERN_ERR "sync returns %d\n", rc);
732 filp_close(filp, NULL);
734 cfs_tracefile_write_unlock();
738 void cfs_trace_flush_pages(void)
740 struct page_collection pc;
741 struct cfs_trace_page *tage;
742 struct cfs_trace_page *tmp;
744 spin_lock_init(&pc.pc_lock);
746 pc.pc_want_daemon_pages = 1;
748 list_for_each_entry_safe(tage, tmp, &pc.pc_pages, linkage) {
750 __LASSERT_TAGE_INVARIANT(tage);
752 list_del(&tage->linkage);
757 int cfs_trace_copyin_string(char *knl_buffer, int knl_buffer_nob,
758 const char __user *usr_buffer, int usr_buffer_nob)
762 if (usr_buffer_nob > knl_buffer_nob)
765 if (copy_from_user((void *)knl_buffer,
766 usr_buffer, usr_buffer_nob))
769 nob = strnlen(knl_buffer, usr_buffer_nob);
770 while (nob-- >= 0) /* strip trailing whitespace */
771 if (!isspace(knl_buffer[nob]))
774 if (nob < 0) /* empty string */
777 if (nob == knl_buffer_nob) /* no space to terminate */
780 knl_buffer[nob + 1] = 0; /* terminate */
783 EXPORT_SYMBOL(cfs_trace_copyin_string);
785 int cfs_trace_copyout_string(char __user *usr_buffer, int usr_buffer_nob,
786 const char *knl_buffer, char *append)
788 /* NB if 'append' != NULL, it's a single character to append to the
789 * copied out string - usually "\n", for /proc entries and "" (i.e. a
790 * terminating zero byte) for sysctl entries */
791 int nob = strlen(knl_buffer);
793 if (nob > usr_buffer_nob)
794 nob = usr_buffer_nob;
796 if (copy_to_user(usr_buffer, knl_buffer, nob))
799 if (append != NULL && nob < usr_buffer_nob) {
800 if (copy_to_user(usr_buffer + nob, append, 1))
808 EXPORT_SYMBOL(cfs_trace_copyout_string);
810 int cfs_trace_allocate_string_buffer(char **str, int nob)
812 if (nob > 2 * PAGE_CACHE_SIZE) /* string must be "sensible" */
815 *str = kmalloc(nob, GFP_IOFS | __GFP_ZERO);
822 void cfs_trace_free_string_buffer(char *str, int nob)
827 int cfs_trace_dump_debug_buffer_usrstr(void __user *usr_str, int usr_str_nob)
832 rc = cfs_trace_allocate_string_buffer(&str, usr_str_nob + 1);
836 rc = cfs_trace_copyin_string(str, usr_str_nob + 1,
837 usr_str, usr_str_nob);
845 rc = cfs_tracefile_dump_all_pages(str);
847 cfs_trace_free_string_buffer(str, usr_str_nob + 1);
851 int cfs_trace_daemon_command(char *str)
855 cfs_tracefile_write_lock();
857 if (strcmp(str, "stop") == 0) {
858 cfs_tracefile_write_unlock();
859 cfs_trace_stop_thread();
860 cfs_tracefile_write_lock();
861 memset(cfs_tracefile, 0, sizeof(cfs_tracefile));
863 } else if (strncmp(str, "size=", 5) == 0) {
864 cfs_tracefile_size = simple_strtoul(str + 5, NULL, 0);
865 if (cfs_tracefile_size < 10 || cfs_tracefile_size > 20480)
866 cfs_tracefile_size = CFS_TRACEFILE_SIZE;
868 cfs_tracefile_size <<= 20;
870 } else if (strlen(str) >= sizeof(cfs_tracefile)) {
872 } else if (str[0] != '/') {
875 strcpy(cfs_tracefile, str);
878 "Lustre: debug daemon will attempt to start writing "
879 "to %s (%lukB max)\n", cfs_tracefile,
880 (long)(cfs_tracefile_size >> 10));
882 cfs_trace_start_thread();
885 cfs_tracefile_write_unlock();
889 int cfs_trace_daemon_command_usrstr(void __user *usr_str, int usr_str_nob)
894 rc = cfs_trace_allocate_string_buffer(&str, usr_str_nob + 1);
898 rc = cfs_trace_copyin_string(str, usr_str_nob + 1,
899 usr_str, usr_str_nob);
901 rc = cfs_trace_daemon_command(str);
903 cfs_trace_free_string_buffer(str, usr_str_nob + 1);
907 int cfs_trace_set_debug_mb(int mb)
912 int limit = cfs_trace_max_debug_mb();
913 struct cfs_trace_cpu_data *tcd;
915 if (mb < num_possible_cpus()) {
917 "Lustre: %d MB is too small for debug buffer size, "
918 "setting it to %d MB.\n", mb, num_possible_cpus());
919 mb = num_possible_cpus();
924 "Lustre: %d MB is too large for debug buffer size, "
925 "setting it to %d MB.\n", mb, limit);
929 mb /= num_possible_cpus();
930 pages = mb << (20 - PAGE_CACHE_SHIFT);
932 cfs_tracefile_write_lock();
934 cfs_tcd_for_each(tcd, i, j)
935 tcd->tcd_max_pages = (pages * tcd->tcd_pages_factor) / 100;
937 cfs_tracefile_write_unlock();
942 int cfs_trace_set_debug_mb_usrstr(void __user *usr_str, int usr_str_nob)
947 rc = cfs_trace_copyin_string(str, sizeof(str), usr_str, usr_str_nob);
951 return cfs_trace_set_debug_mb(simple_strtoul(str, NULL, 0));
954 int cfs_trace_get_debug_mb(void)
958 struct cfs_trace_cpu_data *tcd;
961 cfs_tracefile_read_lock();
963 cfs_tcd_for_each(tcd, i, j)
964 total_pages += tcd->tcd_max_pages;
966 cfs_tracefile_read_unlock();
968 return (total_pages >> (20 - PAGE_CACHE_SHIFT)) + 1;
971 static int tracefiled(void *arg)
973 struct page_collection pc;
974 struct tracefiled_ctl *tctl = arg;
975 struct cfs_trace_page *tage;
976 struct cfs_trace_page *tmp;
984 /* we're started late enough that we pick up init's fs context */
985 /* this is so broken in uml? what on earth is going on? */
987 spin_lock_init(&pc.pc_lock);
988 complete(&tctl->tctl_start);
993 pc.pc_want_daemon_pages = 0;
995 if (list_empty(&pc.pc_pages))
999 cfs_tracefile_read_lock();
1000 if (cfs_tracefile[0] != 0) {
1001 filp = filp_open(cfs_tracefile,
1002 O_CREAT | O_RDWR | O_LARGEFILE,
1007 printk(KERN_WARNING "couldn't open %s: "
1008 "%d\n", cfs_tracefile, rc);
1011 cfs_tracefile_read_unlock();
1013 put_pages_on_daemon_list(&pc);
1014 __LASSERT(list_empty(&pc.pc_pages));
1020 list_for_each_entry_safe(tage, tmp, &pc.pc_pages,
1022 static loff_t f_pos;
1024 __LASSERT_TAGE_INVARIANT(tage);
1026 if (f_pos >= (off_t)cfs_tracefile_size)
1028 else if (f_pos > i_size_read(file_inode(filp)))
1029 f_pos = i_size_read(file_inode(filp));
1031 buf = kmap(tage->page);
1032 rc = vfs_write(filp, (__force const char __user *)buf,
1033 tage->used, &f_pos);
1036 if (rc != (int)tage->used) {
1037 printk(KERN_WARNING "wanted to write %u "
1038 "but wrote %d\n", tage->used, rc);
1039 put_pages_back(&pc);
1040 __LASSERT(list_empty(&pc.pc_pages));
1045 filp_close(filp, NULL);
1046 put_pages_on_daemon_list(&pc);
1047 if (!list_empty(&pc.pc_pages)) {
1050 printk(KERN_ALERT "Lustre: trace pages aren't "
1052 printk(KERN_ERR "total cpus(%d): ",
1053 num_possible_cpus());
1054 for (i = 0; i < num_possible_cpus(); i++)
1056 printk(KERN_ERR "%d(on) ", i);
1058 printk(KERN_ERR "%d(off) ", i);
1059 printk(KERN_ERR "\n");
1062 list_for_each_entry_safe(tage, tmp, &pc.pc_pages,
1064 printk(KERN_ERR "page %d belongs to cpu "
1065 "%d\n", ++i, tage->cpu);
1066 printk(KERN_ERR "There are %d pages unwritten\n",
1069 __LASSERT(list_empty(&pc.pc_pages));
1071 if (atomic_read(&tctl->tctl_shutdown)) {
1072 if (last_loop == 0) {
1079 init_waitqueue_entry(&__wait, current);
1080 add_wait_queue(&tctl->tctl_waitq, &__wait);
1081 set_current_state(TASK_INTERRUPTIBLE);
1082 schedule_timeout(cfs_time_seconds(1));
1083 remove_wait_queue(&tctl->tctl_waitq, &__wait);
1085 complete(&tctl->tctl_stop);
1089 int cfs_trace_start_thread(void)
1091 struct tracefiled_ctl *tctl = &trace_tctl;
1094 mutex_lock(&cfs_trace_thread_mutex);
1098 init_completion(&tctl->tctl_start);
1099 init_completion(&tctl->tctl_stop);
1100 init_waitqueue_head(&tctl->tctl_waitq);
1101 atomic_set(&tctl->tctl_shutdown, 0);
1103 if (IS_ERR(kthread_run(tracefiled, tctl, "ktracefiled"))) {
1108 wait_for_completion(&tctl->tctl_start);
1111 mutex_unlock(&cfs_trace_thread_mutex);
1115 void cfs_trace_stop_thread(void)
1117 struct tracefiled_ctl *tctl = &trace_tctl;
1119 mutex_lock(&cfs_trace_thread_mutex);
1120 if (thread_running) {
1122 "Lustre: shutting down debug daemon thread...\n");
1123 atomic_set(&tctl->tctl_shutdown, 1);
1124 wait_for_completion(&tctl->tctl_stop);
1127 mutex_unlock(&cfs_trace_thread_mutex);
1130 int cfs_tracefile_init(int max_pages)
1132 struct cfs_trace_cpu_data *tcd;
1138 rc = cfs_tracefile_init_arch();
1142 cfs_tcd_for_each(tcd, i, j) {
1143 /* tcd_pages_factor is initialized int tracefile_init_arch. */
1144 factor = tcd->tcd_pages_factor;
1145 INIT_LIST_HEAD(&tcd->tcd_pages);
1146 INIT_LIST_HEAD(&tcd->tcd_stock_pages);
1147 INIT_LIST_HEAD(&tcd->tcd_daemon_pages);
1148 tcd->tcd_cur_pages = 0;
1149 tcd->tcd_cur_stock_pages = 0;
1150 tcd->tcd_cur_daemon_pages = 0;
1151 tcd->tcd_max_pages = (max_pages * factor) / 100;
1152 LASSERT(tcd->tcd_max_pages > 0);
1153 tcd->tcd_shutting_down = 0;
1159 static void trace_cleanup_on_all_cpus(void)
1161 struct cfs_trace_cpu_data *tcd;
1162 struct cfs_trace_page *tage;
1163 struct cfs_trace_page *tmp;
1166 for_each_possible_cpu(cpu) {
1167 cfs_tcd_for_each_type_lock(tcd, i, cpu) {
1168 tcd->tcd_shutting_down = 1;
1170 list_for_each_entry_safe(tage, tmp, &tcd->tcd_pages,
1172 __LASSERT_TAGE_INVARIANT(tage);
1174 list_del(&tage->linkage);
1175 cfs_tage_free(tage);
1178 tcd->tcd_cur_pages = 0;
1183 static void cfs_trace_cleanup(void)
1185 struct page_collection pc;
1187 INIT_LIST_HEAD(&pc.pc_pages);
1188 spin_lock_init(&pc.pc_lock);
1190 trace_cleanup_on_all_cpus();
1192 cfs_tracefile_fini_arch();
1195 void cfs_tracefile_exit(void)
1197 cfs_trace_stop_thread();
1198 cfs_trace_cleanup();