diff options
Diffstat (limited to 'drivers/staging/lustre/lustre/libcfs/tracefile.c')
| -rw-r--r-- | drivers/staging/lustre/lustre/libcfs/tracefile.c | 1195 |
1 files changed, 1195 insertions, 0 deletions
diff --git a/drivers/staging/lustre/lustre/libcfs/tracefile.c b/drivers/staging/lustre/lustre/libcfs/tracefile.c new file mode 100644 index 000000000000..439e71dfae33 --- /dev/null +++ b/drivers/staging/lustre/lustre/libcfs/tracefile.c @@ -0,0 +1,1195 @@ +/* + * GPL HEADER START + * + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 only, + * as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License version 2 for more details (a copy is included + * in the LICENSE file that accompanied this code). + * + * You should have received a copy of the GNU General Public License + * version 2 along with this program; If not, see + * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf + * + * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, + * CA 95054 USA or visit www.sun.com if you need additional information or + * have any questions. + * + * GPL HEADER END + */ +/* + * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved. + * Use is subject to license terms. + * + * Copyright (c) 2012, Intel Corporation. + */ +/* + * This file is part of Lustre, http://www.lustre.org/ + * Lustre is a trademark of Sun Microsystems, Inc. + * + * libcfs/libcfs/tracefile.c + * + * Author: Zach Brown <zab@clusterfs.com> + * Author: Phil Schwan <phil@clusterfs.com> + */ + + +#define DEBUG_SUBSYSTEM S_LNET +#define LUSTRE_TRACEFILE_PRIVATE +#include "tracefile.h" + +#include <linux/libcfs/libcfs.h> + +/* XXX move things up to the top, comment */ +union cfs_trace_data_union (*cfs_trace_data[TCD_MAX_TYPES])[NR_CPUS] __cacheline_aligned; + +char cfs_tracefile[TRACEFILE_NAME_SIZE]; +long long cfs_tracefile_size = CFS_TRACEFILE_SIZE; +static struct tracefiled_ctl trace_tctl; +struct mutex cfs_trace_thread_mutex; +static int thread_running = 0; + +atomic_t cfs_tage_allocated = ATOMIC_INIT(0); + +static void put_pages_on_tcd_daemon_list(struct page_collection *pc, + struct cfs_trace_cpu_data *tcd); + +static inline struct cfs_trace_page * +cfs_tage_from_list(struct list_head *list) +{ + return list_entry(list, struct cfs_trace_page, linkage); +} + +static struct cfs_trace_page *cfs_tage_alloc(int gfp) +{ + struct page *page; + struct cfs_trace_page *tage; + + /* My caller is trying to free memory */ + if (!in_interrupt() && memory_pressure_get()) + return NULL; + + /* + * Don't spam console with allocation failures: they will be reported + * by upper layer anyway. + */ + gfp |= __GFP_NOWARN; + page = alloc_page(gfp); + if (page == NULL) + return NULL; + + tage = kmalloc(sizeof(*tage), gfp); + if (tage == NULL) { + __free_page(page); + return NULL; + } + + tage->page = page; + atomic_inc(&cfs_tage_allocated); + return tage; +} + +static void cfs_tage_free(struct cfs_trace_page *tage) +{ + __LASSERT(tage != NULL); + __LASSERT(tage->page != NULL); + + __free_page(tage->page); + kfree(tage); + atomic_dec(&cfs_tage_allocated); +} + +static void cfs_tage_to_tail(struct cfs_trace_page *tage, + struct list_head *queue) +{ + __LASSERT(tage != NULL); + __LASSERT(queue != NULL); + + list_move_tail(&tage->linkage, queue); +} + +int cfs_trace_refill_stock(struct cfs_trace_cpu_data *tcd, int gfp, + struct list_head *stock) +{ + int i; + + /* + * XXX nikita: do NOT call portals_debug_msg() (CDEBUG/ENTRY/EXIT) + * from here: this will lead to infinite recursion. + */ + + for (i = 0; i + tcd->tcd_cur_stock_pages < TCD_STOCK_PAGES ; ++ i) { + struct cfs_trace_page *tage; + + tage = cfs_tage_alloc(gfp); + if (tage == NULL) + break; + list_add_tail(&tage->linkage, stock); + } + return i; +} + +/* return a page that has 'len' bytes left at the end */ +static struct cfs_trace_page * +cfs_trace_get_tage_try(struct cfs_trace_cpu_data *tcd, unsigned long len) +{ + struct cfs_trace_page *tage; + + if (tcd->tcd_cur_pages > 0) { + __LASSERT(!list_empty(&tcd->tcd_pages)); + tage = cfs_tage_from_list(tcd->tcd_pages.prev); + if (tage->used + len <= PAGE_CACHE_SIZE) + return tage; + } + + if (tcd->tcd_cur_pages < tcd->tcd_max_pages) { + if (tcd->tcd_cur_stock_pages > 0) { + tage = cfs_tage_from_list(tcd->tcd_stock_pages.prev); + --tcd->tcd_cur_stock_pages; + list_del_init(&tage->linkage); + } else { + tage = cfs_tage_alloc(GFP_ATOMIC); + if (unlikely(tage == NULL)) { + if ((!memory_pressure_get() || + in_interrupt()) && printk_ratelimit()) + printk(KERN_WARNING + "cannot allocate a tage (%ld)\n", + tcd->tcd_cur_pages); + return NULL; + } + } + + tage->used = 0; + tage->cpu = smp_processor_id(); + tage->type = tcd->tcd_type; + list_add_tail(&tage->linkage, &tcd->tcd_pages); + tcd->tcd_cur_pages++; + + if (tcd->tcd_cur_pages > 8 && thread_running) { + struct tracefiled_ctl *tctl = &trace_tctl; + /* + * wake up tracefiled to process some pages. + */ + wake_up(&tctl->tctl_waitq); + } + return tage; + } + return NULL; +} + +static void cfs_tcd_shrink(struct cfs_trace_cpu_data *tcd) +{ + int pgcount = tcd->tcd_cur_pages / 10; + struct page_collection pc; + struct cfs_trace_page *tage; + struct cfs_trace_page *tmp; + + /* + * XXX nikita: do NOT call portals_debug_msg() (CDEBUG/ENTRY/EXIT) + * from here: this will lead to infinite recursion. + */ + + if (printk_ratelimit()) + printk(KERN_WARNING "debug daemon buffer overflowed; " + "discarding 10%% of pages (%d of %ld)\n", + pgcount + 1, tcd->tcd_cur_pages); + + INIT_LIST_HEAD(&pc.pc_pages); + spin_lock_init(&pc.pc_lock); + + list_for_each_entry_safe(tage, tmp, &tcd->tcd_pages, linkage) { + if (pgcount-- == 0) + break; + + list_move_tail(&tage->linkage, &pc.pc_pages); + tcd->tcd_cur_pages--; + } + put_pages_on_tcd_daemon_list(&pc, tcd); +} + +/* return a page that has 'len' bytes left at the end */ +static struct cfs_trace_page *cfs_trace_get_tage(struct cfs_trace_cpu_data *tcd, + unsigned long len) +{ + struct cfs_trace_page *tage; + + /* + * XXX nikita: do NOT call portals_debug_msg() (CDEBUG/ENTRY/EXIT) + * from here: this will lead to infinite recursion. + */ + + if (len > PAGE_CACHE_SIZE) { + printk(KERN_ERR + "cowardly refusing to write %lu bytes in a page\n", len); + return NULL; + } + + tage = cfs_trace_get_tage_try(tcd, len); + if (tage != NULL) + return tage; + if (thread_running) + cfs_tcd_shrink(tcd); + if (tcd->tcd_cur_pages > 0) { + tage = cfs_tage_from_list(tcd->tcd_pages.next); + tage->used = 0; + cfs_tage_to_tail(tage, &tcd->tcd_pages); + } + return tage; +} + +int libcfs_debug_msg(struct libcfs_debug_msg_data *msgdata, + const char *format, ...) +{ + va_list args; + int rc; + + va_start(args, format); + rc = libcfs_debug_vmsg2(msgdata, format, args, NULL); + va_end(args); + + return rc; +} +EXPORT_SYMBOL(libcfs_debug_msg); + +int libcfs_debug_vmsg2(struct libcfs_debug_msg_data *msgdata, + const char *format1, va_list args, + const char *format2, ...) +{ + struct cfs_trace_cpu_data *tcd = NULL; + struct ptldebug_header header = {0}; + struct cfs_trace_page *tage; + /* string_buf is used only if tcd != NULL, and is always set then */ + char *string_buf = NULL; + char *debug_buf; + int known_size; + int needed = 85; /* average message length */ + int max_nob; + va_list ap; + int depth; + int i; + int remain; + int mask = msgdata->msg_mask; + char *file = (char *)msgdata->msg_file; + cfs_debug_limit_state_t *cdls = msgdata->msg_cdls; + + if (strchr(file, '/')) + file = strrchr(file, '/') + 1; + + tcd = cfs_trace_get_tcd(); + + /* cfs_trace_get_tcd() grabs a lock, which disables preemption and + * pins us to a particular CPU. This avoids an smp_processor_id() + * warning on Linux when debugging is enabled. */ + cfs_set_ptldebug_header(&header, msgdata, CDEBUG_STACK()); + + if (tcd == NULL) /* arch may not log in IRQ context */ + goto console; + + if (tcd->tcd_cur_pages == 0) + header.ph_flags |= PH_FLAG_FIRST_RECORD; + + if (tcd->tcd_shutting_down) { + cfs_trace_put_tcd(tcd); + tcd = NULL; + goto console; + } + + depth = __current_nesting_level(); + known_size = strlen(file) + 1 + depth; + if (msgdata->msg_fn) + known_size += strlen(msgdata->msg_fn) + 1; + + if (libcfs_debug_binary) + known_size += sizeof(header); + + /*/ + * '2' used because vsnprintf return real size required for output + * _without_ terminating NULL. + * if needed is to small for this format. + */ + for (i = 0; i < 2; i++) { + tage = cfs_trace_get_tage(tcd, needed + known_size + 1); + if (tage == NULL) { + if (needed + known_size > PAGE_CACHE_SIZE) + mask |= D_ERROR; + + cfs_trace_put_tcd(tcd); + tcd = NULL; + goto console; + } + + string_buf = (char *)page_address(tage->page) + + tage->used + known_size; + + max_nob = PAGE_CACHE_SIZE - tage->used - known_size; + if (max_nob <= 0) { + printk(KERN_EMERG "negative max_nob: %d\n", + max_nob); + mask |= D_ERROR; + cfs_trace_put_tcd(tcd); + tcd = NULL; + goto console; + } + + needed = 0; + if (format1) { + va_copy(ap, args); + needed = vsnprintf(string_buf, max_nob, format1, ap); + va_end(ap); + } + + if (format2) { + remain = max_nob - needed; + if (remain < 0) + remain = 0; + + va_start(ap, format2); + needed += vsnprintf(string_buf + needed, remain, + format2, ap); + va_end(ap); + } + + if (needed < max_nob) /* well. printing ok.. */ + break; + } + + if (*(string_buf+needed-1) != '\n') + printk(KERN_INFO "format at %s:%d:%s doesn't end in " + "newline\n", file, msgdata->msg_line, msgdata->msg_fn); + + header.ph_len = known_size + needed; + debug_buf = (char *)page_address(tage->page) + tage->used; + + if (libcfs_debug_binary) { + memcpy(debug_buf, &header, sizeof(header)); + tage->used += sizeof(header); + debug_buf += sizeof(header); + } + + /* indent message according to the nesting level */ + while (depth-- > 0) { + *(debug_buf++) = '.'; + ++ tage->used; + } + + strcpy(debug_buf, file); + tage->used += strlen(file) + 1; + debug_buf += strlen(file) + 1; + + if (msgdata->msg_fn) { + strcpy(debug_buf, msgdata->msg_fn); + tage->used += strlen(msgdata->msg_fn) + 1; + debug_buf += strlen(msgdata->msg_fn) + 1; + } + + __LASSERT(debug_buf == string_buf); + + tage->used += needed; + __LASSERT (tage->used <= PAGE_CACHE_SIZE); + +console: + if ((mask & libcfs_printk) == 0) { + /* no console output requested */ + if (tcd != NULL) + cfs_trace_put_tcd(tcd); + return 1; + } + + if (cdls != NULL) { + if (libcfs_console_ratelimit && + cdls->cdls_next != 0 && /* not first time ever */ + !cfs_time_after(cfs_time_current(), cdls->cdls_next)) { + /* skipping a console message */ + cdls->cdls_count++; + if (tcd != NULL) + cfs_trace_put_tcd(tcd); + return 1; + } + + if (cfs_time_after(cfs_time_current(), cdls->cdls_next + + libcfs_console_max_delay + + cfs_time_seconds(10))) { + /* last timeout was a long time ago */ + cdls->cdls_delay /= libcfs_console_backoff * 4; + } else { + cdls->cdls_delay *= libcfs_console_backoff; + + if (cdls->cdls_delay < libcfs_console_min_delay) + cdls->cdls_delay = libcfs_console_min_delay; + else if (cdls->cdls_delay > libcfs_console_max_delay) + cdls->cdls_delay = libcfs_console_max_delay; + } + + /* ensure cdls_next is never zero after it's been seen */ + cdls->cdls_next = (cfs_time_current() + cdls->cdls_delay) | 1; + } + + if (tcd != NULL) { + cfs_print_to_console(&header, mask, string_buf, needed, file, + msgdata->msg_fn); + cfs_trace_put_tcd(tcd); + } else { + string_buf = cfs_trace_get_console_buffer(); + + needed = 0; + if (format1 != NULL) { + va_copy(ap, args); + needed = vsnprintf(string_buf, + CFS_TRACE_CONSOLE_BUFFER_SIZE, + format1, ap); + va_end(ap); + } + if (format2 != NULL) { + remain = CFS_TRACE_CONSOLE_BUFFER_SIZE - needed; + if (remain > 0) { + va_start(ap, format2); + needed += vsnprintf(string_buf+needed, remain, + format2, ap); + va_end(ap); + } + } + cfs_print_to_console(&header, mask, + string_buf, needed, file, msgdata->msg_fn); + + cfs_trace_put_console_buffer(string_buf); + } + + if (cdls != NULL && cdls->cdls_count != 0) { + string_buf = cfs_trace_get_console_buffer(); + + needed = snprintf(string_buf, CFS_TRACE_CONSOLE_BUFFER_SIZE, + "Skipped %d previous similar message%s\n", + cdls->cdls_count, + (cdls->cdls_count > 1) ? "s" : ""); + + cfs_print_to_console(&header, mask, + string_buf, needed, file, msgdata->msg_fn); + + cfs_trace_put_console_buffer(string_buf); + cdls->cdls_count = 0; + } + + return 0; +} +EXPORT_SYMBOL(libcfs_debug_vmsg2); + +void +cfs_trace_assertion_failed(const char *str, + struct libcfs_debug_msg_data *msgdata) +{ + struct ptldebug_header hdr; + + libcfs_panic_in_progress = 1; + libcfs_catastrophe = 1; + mb(); + + cfs_set_ptldebug_header(&hdr, msgdata, CDEBUG_STACK()); + + cfs_print_to_console(&hdr, D_EMERG, str, strlen(str), + msgdata->msg_file, msgdata->msg_fn); + + panic("Lustre debug assertion failure\n"); + + /* not reached */ +} + +static void +panic_collect_pages(struct page_collection *pc) +{ + /* Do the collect_pages job on a single CPU: assumes that all other + * CPUs have been stopped during a panic. If this isn't true for some + * arch, this will have to be implemented separately in each arch. */ + int i; + int j; + struct cfs_trace_cpu_data *tcd; + + INIT_LIST_HEAD(&pc->pc_pages); + + cfs_tcd_for_each(tcd, i, j) { + list_splice_init(&tcd->tcd_pages, &pc->pc_pages); + tcd->tcd_cur_pages = 0; + + if (pc->pc_want_daemon_pages) { + list_splice_init(&tcd->tcd_daemon_pages, + &pc->pc_pages); + tcd->tcd_cur_daemon_pages = 0; + } + } +} + +static void collect_pages_on_all_cpus(struct page_collection *pc) +{ + struct cfs_trace_cpu_data *tcd; + int i, cpu; + + spin_lock(&pc->pc_lock); + cfs_for_each_possible_cpu(cpu) { + cfs_tcd_for_each_type_lock(tcd, i, cpu) { + list_splice_init(&tcd->tcd_pages, &pc->pc_pages); + tcd->tcd_cur_pages = 0; + if (pc->pc_want_daemon_pages) { + list_splice_init(&tcd->tcd_daemon_pages, + &pc->pc_pages); + tcd->tcd_cur_daemon_pages = 0; + } + } + } + spin_unlock(&pc->pc_lock); +} + +static void collect_pages(struct page_collection *pc) +{ + INIT_LIST_HEAD(&pc->pc_pages); + + if (libcfs_panic_in_progress) + panic_collect_pages(pc); + else + collect_pages_on_all_cpus(pc); +} + +static void put_pages_back_on_all_cpus(struct page_collection *pc) +{ + struct cfs_trace_cpu_data *tcd; + struct list_head *cur_head; + struct cfs_trace_page *tage; + struct cfs_trace_page *tmp; + int i, cpu; + + spin_lock(&pc->pc_lock); + cfs_for_each_possible_cpu(cpu) { + cfs_tcd_for_each_type_lock(tcd, i, cpu) { + cur_head = tcd->tcd_pages.next; + + list_for_each_entry_safe(tage, tmp, &pc->pc_pages, + linkage) { + + __LASSERT_TAGE_INVARIANT(tage); + + if (tage->cpu != cpu || tage->type != i) + continue; + + cfs_tage_to_tail(tage, cur_head); + tcd->tcd_cur_pages++; + } + } + } + spin_unlock(&pc->pc_lock); +} + +static void put_pages_back(struct page_collection *pc) +{ + if (!libcfs_panic_in_progress) + put_pages_back_on_all_cpus(pc); +} + +/* Add pages to a per-cpu debug daemon ringbuffer. This buffer makes sure that + * we have a good amount of data at all times for dumping during an LBUG, even + * if we have been steadily writing (and otherwise discarding) pages via the + * debug daemon. */ +static void put_pages_on_tcd_daemon_list(struct page_collection *pc, + struct cfs_trace_cpu_data *tcd) +{ + struct cfs_trace_page *tage; + struct cfs_trace_page *tmp; + + spin_lock(&pc->pc_lock); + list_for_each_entry_safe(tage, tmp, &pc->pc_pages, linkage) { + + __LASSERT_TAGE_INVARIANT(tage); + + if (tage->cpu != tcd->tcd_cpu || tage->type != tcd->tcd_type) + continue; + + cfs_tage_to_tail(tage, &tcd->tcd_daemon_pages); + tcd->tcd_cur_daemon_pages++; + + if (tcd->tcd_cur_daemon_pages > tcd->tcd_max_pages) { + struct cfs_trace_page *victim; + + __LASSERT(!list_empty(&tcd->tcd_daemon_pages)); + victim = cfs_tage_from_list(tcd->tcd_daemon_pages.next); + + __LASSERT_TAGE_INVARIANT(victim); + + list_del(&victim->linkage); + cfs_tage_free(victim); + tcd->tcd_cur_daemon_pages--; + } + } + spin_unlock(&pc->pc_lock); +} + +static void put_pages_on_daemon_list(struct page_collection *pc) +{ + struct cfs_trace_cpu_data *tcd; + int i, cpu; + + cfs_for_each_possible_cpu(cpu) { + cfs_tcd_for_each_type_lock(tcd, i, cpu) + put_pages_on_tcd_daemon_list(pc, tcd); + } +} + +void cfs_trace_debug_print(void) +{ + struct page_collection pc; + struct cfs_trace_page *tage; + struct cfs_trace_page *tmp; + + spin_lock_init(&pc.pc_lock); + + pc.pc_want_daemon_pages = 1; + collect_pages(&pc); + list_for_each_entry_safe(tage, tmp, &pc.pc_pages, linkage) { + char *p, *file, *fn; + struct page *page; + + __LASSERT_TAGE_INVARIANT(tage); + + page = tage->page; + p = page_address(page); + while (p < ((char *)page_address(page) + tage->used)) { + struct ptldebug_header *hdr; + int len; + hdr = (void *)p; + p += sizeof(*hdr); + file = p; + p += strlen(file) + 1; + fn = p; + p += strlen(fn) + 1; + len = hdr->ph_len - (int)(p - (char *)hdr); + + cfs_print_to_console(hdr, D_EMERG, p, len, file, fn); + + p += len; + } + + list_del(&tage->linkage); + cfs_tage_free(tage); + } +} + +int cfs_tracefile_dump_all_pages(char *filename) +{ + struct page_collection pc; + struct file *filp; + struct cfs_trace_page *tage; + struct cfs_trace_page *tmp; + int rc; + + DECL_MMSPACE; + + cfs_tracefile_write_lock(); + + filp = filp_open(filename, O_CREAT|O_EXCL|O_WRONLY|O_LARGEFILE, 0600); + if (IS_ERR(filp)) { + rc = PTR_ERR(filp); + filp = NULL; + printk(KERN_ERR "LustreError: can't open %s for dump: rc %d\n", + filename, rc); + goto out; + } + + spin_lock_init(&pc.pc_lock); + pc.pc_want_daemon_pages = 1; + collect_pages(&pc); + if (list_empty(&pc.pc_pages)) { + rc = 0; + goto close; + } + + /* ok, for now, just write the pages. in the future we'll be building + * iobufs with the pages and calling generic_direct_IO */ + MMSPACE_OPEN; + list_for_each_entry_safe(tage, tmp, &pc.pc_pages, linkage) { + + __LASSERT_TAGE_INVARIANT(tage); + + rc = filp_write(filp, page_address(tage->page), + tage->used, filp_poff(filp)); + if (rc != (int)tage->used) { + printk(KERN_WARNING "wanted to write %u but wrote " + "%d\n", tage->used, rc); + put_pages_back(&pc); + __LASSERT(list_empty(&pc.pc_pages)); + break; + } + list_del(&tage->linkage); + cfs_tage_free(tage); + } + MMSPACE_CLOSE; + rc = filp_fsync(filp); + if (rc) + printk(KERN_ERR "sync returns %d\n", rc); +close: + filp_close(filp, NULL); +out: + cfs_tracefile_write_unlock(); + return rc; +} + +void cfs_trace_flush_pages(void) +{ + struct page_collection pc; + struct cfs_trace_page *tage; + struct cfs_trace_page *tmp; + + spin_lock_init(&pc.pc_lock); + + pc.pc_want_daemon_pages = 1; + collect_pages(&pc); + list_for_each_entry_safe(tage, tmp, &pc.pc_pages, linkage) { + + __LASSERT_TAGE_INVARIANT(tage); + + list_del(&tage->linkage); + cfs_tage_free(tage); + } +} + +int cfs_trace_copyin_string(char *knl_buffer, int knl_buffer_nob, + const char *usr_buffer, int usr_buffer_nob) +{ + int nob; + + if (usr_buffer_nob > knl_buffer_nob) + return -EOVERFLOW; + + if (copy_from_user((void *)knl_buffer, + (void *)usr_buffer, usr_buffer_nob)) + return -EFAULT; + + nob = strnlen(knl_buffer, usr_buffer_nob); + while (nob-- >= 0) /* strip trailing whitespace */ + if (!isspace(knl_buffer[nob])) + break; + + if (nob < 0) /* empty string */ + return -EINVAL; + + if (nob == knl_buffer_nob) /* no space to terminate */ + return -EOVERFLOW; + + knl_buffer[nob + 1] = 0; /* terminate */ + return 0; +} +EXPORT_SYMBOL(cfs_trace_copyin_string); + +int cfs_trace_copyout_string(char *usr_buffer, int usr_buffer_nob, + const char *knl_buffer, char *append) +{ + /* NB if 'append' != NULL, it's a single character to append to the + * copied out string - usually "\n", for /proc entries and "" (i.e. a + * terminating zero byte) for sysctl entries */ + int nob = strlen(knl_buffer); + + if (nob > usr_buffer_nob) + nob = usr_buffer_nob; + + if (copy_to_user(usr_buffer, knl_buffer, nob)) + return -EFAULT; + + if (append != NULL && nob < usr_buffer_nob) { + if (copy_to_user(usr_buffer + nob, append, 1)) + return -EFAULT; + + nob++; + } + + return nob; +} +EXPORT_SYMBOL(cfs_trace_copyout_string); + +int cfs_trace_allocate_string_buffer(char **str, int nob) +{ + if (nob > 2 * PAGE_CACHE_SIZE) /* string must be "sensible" */ + return -EINVAL; + + *str = kmalloc(nob, GFP_IOFS | __GFP_ZERO); + if (*str == NULL) + return -ENOMEM; + + return 0; +} + +void cfs_trace_free_string_buffer(char *str, int nob) +{ + kfree(str); +} + +int cfs_trace_dump_debug_buffer_usrstr(void *usr_str, int usr_str_nob) +{ + char *str; + int rc; + + rc = cfs_trace_allocate_string_buffer(&str, usr_str_nob + 1); + if (rc != 0) + return rc; + + rc = cfs_trace_copyin_string(str, usr_str_nob + 1, + usr_str, usr_str_nob); + if (rc != 0) + goto out; + + if (str[0] != '/') { + rc = -EINVAL; + goto out; + } + rc = cfs_tracefile_dump_all_pages(str); +out: + cfs_trace_free_string_buffer(str, usr_str_nob + 1); + return rc; +} + +int cfs_trace_daemon_command(char *str) +{ + int rc = 0; + + cfs_tracefile_write_lock(); + + if (strcmp(str, "stop") == 0) { + cfs_tracefile_write_unlock(); + cfs_trace_stop_thread(); + cfs_tracefile_write_lock(); + memset(cfs_tracefile, 0, sizeof(cfs_tracefile)); + + } else if (strncmp(str, "size=", 5) == 0) { + cfs_tracefile_size = simple_strtoul(str + 5, NULL, 0); + if (cfs_tracefile_size < 10 || cfs_tracefile_size > 20480) + cfs_tracefile_size = CFS_TRACEFILE_SIZE; + else + cfs_tracefile_size <<= 20; + + } else if (strlen(str) >= sizeof(cfs_tracefile)) { + rc = -ENAMETOOLONG; + } else if (str[0] != '/') { + rc = -EINVAL; + } else { + strcpy(cfs_tracefile, str); + + printk(KERN_INFO + "Lustre: debug daemon will attempt to start writing " + "to %s (%lukB max)\n", cfs_tracefile, + (long)(cfs_tracefile_size >> 10)); + + cfs_trace_start_thread(); + } + + cfs_tracefile_write_unlock(); + return rc; +} + +int cfs_trace_daemon_command_usrstr(void *usr_str, int usr_str_nob) +{ + char *str; + int rc; + + rc = cfs_trace_allocate_string_buffer(&str, usr_str_nob + 1); + if (rc != 0) + return rc; + + rc = cfs_trace_copyin_string(str, usr_str_nob + 1, + usr_str, usr_str_nob); + if (rc == 0) + rc = cfs_trace_daemon_command(str); + + cfs_trace_free_string_buffer(str, usr_str_nob + 1); + return rc; +} + +int cfs_trace_set_debug_mb(int mb) +{ + int i; + int j; + int pages; + int limit = cfs_trace_max_debug_mb(); + struct cfs_trace_cpu_data *tcd; + + if (mb < num_possible_cpus()) { + printk(KERN_WARNING + "Lustre: %d MB is too small for debug buffer size, " + "setting it to %d MB.\n", mb, num_possible_cpus()); + mb = num_possible_cpus(); + } + + if (mb > limit) { + printk(KERN_WARNING + "Lustre: %d MB is too large for debug buffer size, " + "setting it to %d MB.\n", mb, limit); + mb = limit; + } + + mb /= num_possible_cpus(); + pages = mb << (20 - PAGE_CACHE_SHIFT); + + cfs_tracefile_write_lock(); + + cfs_tcd_for_each(tcd, i, j) + tcd->tcd_max_pages = (pages * tcd->tcd_pages_factor) / 100; + + cfs_tracefile_write_unlock(); + + return 0; +} + +int cfs_trace_set_debug_mb_usrstr(void *usr_str, int usr_str_nob) +{ + char str[32]; + int rc; + + rc = cfs_trace_copyin_string(str, sizeof(str), usr_str, usr_str_nob); + if (rc < 0) + return rc; + + return cfs_trace_set_debug_mb(simple_strtoul(str, NULL, 0)); +} + +int cfs_trace_get_debug_mb(void) +{ + int i; + int j; + struct cfs_trace_cpu_data *tcd; + int total_pages = 0; + + cfs_tracefile_read_lock(); + + cfs_tcd_for_each(tcd, i, j) + total_pages += tcd->tcd_max_pages; + + cfs_tracefile_read_unlock(); + + return (total_pages >> (20 - PAGE_CACHE_SHIFT)) + 1; +} + +static int tracefiled(void *arg) +{ + struct page_collection pc; + struct tracefiled_ctl *tctl = arg; + struct cfs_trace_page *tage; + struct cfs_trace_page *tmp; + struct file *filp; + int last_loop = 0; + int rc; + + DECL_MMSPACE; + + /* we're started late enough that we pick up init's fs context */ + /* this is so broken in uml? what on earth is going on? */ + + spin_lock_init(&pc.pc_lock); + complete(&tctl->tctl_start); + + while (1) { + wait_queue_t __wait; + + pc.pc_want_daemon_pages = 0; + collect_pages(&pc); + if (list_empty(&pc.pc_pages)) + goto end_loop; + + filp = NULL; + cfs_tracefile_read_lock(); + if (cfs_tracefile[0] != 0) { + filp = filp_open(cfs_tracefile, + O_CREAT | O_RDWR | O_LARGEFILE, + 0600); + if (IS_ERR(filp)) { + rc = PTR_ERR(filp); + filp = NULL; + printk(KERN_WARNING "couldn't open %s: " + "%d\n", cfs_tracefile, rc); + } + } + cfs_tracefile_read_unlock(); + if (filp == NULL) { + put_pages_on_daemon_list(&pc); + __LASSERT(list_empty(&pc.pc_pages)); + goto end_loop; + } + + MMSPACE_OPEN; + + list_for_each_entry_safe(tage, tmp, &pc.pc_pages, + linkage) { + static loff_t f_pos; + + __LASSERT_TAGE_INVARIANT(tage); + + if (f_pos >= (off_t)cfs_tracefile_size) + f_pos = 0; + else if (f_pos > (off_t)filp_size(filp)) + f_pos = filp_size(filp); + + rc = filp_write(filp, page_address(tage->page), + tage->used, &f_pos); + if (rc != (int)tage->used) { + printk(KERN_WARNING "wanted to write %u " + "but wrote %d\n", tage->used, rc); + put_pages_back(&pc); + __LASSERT(list_empty(&pc.pc_pages)); + } + } + MMSPACE_CLOSE; + + filp_close(filp, NULL); + put_pages_on_daemon_list(&pc); + if (!list_empty(&pc.pc_pages)) { + int i; + + printk(KERN_ALERT "Lustre: trace pages aren't " + " empty\n"); + printk(KERN_ERR "total cpus(%d): ", + num_possible_cpus()); + for (i = 0; i < num_possible_cpus(); i++) + if (cpu_online(i)) + printk(KERN_ERR "%d(on) ", i); + else + printk(KERN_ERR "%d(off) ", i); + printk(KERN_ERR "\n"); + + i = 0; + list_for_each_entry_safe(tage, tmp, &pc.pc_pages, + linkage) + printk(KERN_ERR "page %d belongs to cpu " + "%d\n", ++i, tage->cpu); + printk(KERN_ERR "There are %d pages unwritten\n", + i); + } + __LASSERT(list_empty(&pc.pc_pages)); +end_loop: + if (atomic_read(&tctl->tctl_shutdown)) { + if (last_loop == 0) { + last_loop = 1; + continue; + } else { + break; + } + } + init_waitqueue_entry_current(&__wait); + add_wait_queue(&tctl->tctl_waitq, &__wait); + set_current_state(TASK_INTERRUPTIBLE); + waitq_timedwait(&__wait, TASK_INTERRUPTIBLE, + cfs_time_seconds(1)); + remove_wait_queue(&tctl->tctl_waitq, &__wait); + } + complete(&tctl->tctl_stop); + return 0; +} + +int cfs_trace_start_thread(void) +{ + struct tracefiled_ctl *tctl = &trace_tctl; + int rc = 0; + + mutex_lock(&cfs_trace_thread_mutex); + if (thread_running) + goto out; + + init_completion(&tctl->tctl_start); + init_completion(&tctl->tctl_stop); + init_waitqueue_head(&tctl->tctl_waitq); + atomic_set(&tctl->tctl_shutdown, 0); + + if (IS_ERR(kthread_run(tracefiled, tctl, "ktracefiled"))) { + rc = -ECHILD; + goto out; + } + + wait_for_completion(&tctl->tctl_start); + thread_running = 1; +out: + mutex_unlock(&cfs_trace_thread_mutex); + return rc; +} + +void cfs_trace_stop_thread(void) +{ + struct tracefiled_ctl *tctl = &trace_tctl; + + mutex_lock(&cfs_trace_thread_mutex); + if (thread_running) { + printk(KERN_INFO + "Lustre: shutting down debug daemon thread...\n"); + atomic_set(&tctl->tctl_shutdown, 1); + wait_for_completion(&tctl->tctl_stop); + thread_running = 0; + } + mutex_unlock(&cfs_trace_thread_mutex); +} + +int cfs_tracefile_init(int max_pages) +{ + struct cfs_trace_cpu_data *tcd; + int i; + int j; + int rc; + int factor; + + rc = cfs_tracefile_init_arch(); + if (rc != 0) + return rc; + + cfs_tcd_for_each(tcd, i, j) { + /* tcd_pages_factor is initialized int tracefile_init_arch. */ + factor = tcd->tcd_pages_factor; + INIT_LIST_HEAD(&tcd->tcd_pages); + INIT_LIST_HEAD(&tcd->tcd_stock_pages); + INIT_LIST_HEAD(&tcd->tcd_daemon_pages); + tcd->tcd_cur_pages = 0; + tcd->tcd_cur_stock_pages = 0; + tcd->tcd_cur_daemon_pages = 0; + tcd->tcd_max_pages = (max_pages * factor) / 100; + LASSERT(tcd->tcd_max_pages > 0); + tcd->tcd_shutting_down = 0; + } + + return 0; +} + +static void trace_cleanup_on_all_cpus(void) +{ + struct cfs_trace_cpu_data *tcd; + struct cfs_trace_page *tage; + struct cfs_trace_page *tmp; + int i, cpu; + + cfs_for_each_possible_cpu(cpu) { + cfs_tcd_for_each_type_lock(tcd, i, cpu) { + tcd->tcd_shutting_down = 1; + + list_for_each_entry_safe(tage, tmp, &tcd->tcd_pages, + linkage) { + __LASSERT_TAGE_INVARIANT(tage); + + list_del(&tage->linkage); + cfs_tage_free(tage); + } + + tcd->tcd_cur_pages = 0; + } + } +} + +static void cfs_trace_cleanup(void) +{ + struct page_collection pc; + + INIT_LIST_HEAD(&pc.pc_pages); + spin_lock_init(&pc.pc_lock); + + trace_cleanup_on_all_cpus(); + + cfs_tracefile_fini_arch(); +} + +void cfs_tracefile_exit(void) +{ + cfs_trace_stop_thread(); + cfs_trace_cleanup(); +} |