+++ /dev/null
-/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
- * vim:expandtab:shiftwidth=8:tabstop=8:
- *
- * Copyright (C) 2004 Cluster File Systems, Inc.
- * Author: Zach Brown <zab@clusterfs.com>
- * Author: Phil Schwan <phil@clusterfs.com>
- *
- * This file is part of Lustre, http://www.lustre.org.
- *
- * Lustre is free software; you can redistribute it and/or
- * modify it under the terms of version 2 of the GNU General Public
- * License as published by the Free Software Foundation.
- *
- * Lustre 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 for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with Lustre; if not, write to the Free Software
- * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- */
-
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/init.h>
-#include <linux/rwsem.h>
-#include <linux/proc_fs.h>
-#include <linux/file.h>
-#include <linux/smp.h>
-#include <linux/ctype.h>
-#include <asm/uaccess.h>
-#ifdef HAVE_MM_INLINE
-#include <linux/mm_inline.h>
-#endif
-
-#define DEBUG_SUBSYSTEM S_PORTALS
-
-#include <linux/kp30.h>
-#include <linux/portals_compat25.h>
-#include <linux/libcfs.h>
-
-#define TCD_MAX_PAGES (5 << (20 - PAGE_SHIFT))
-
-/* XXX move things up to the top, comment */
-
-static union {
- struct trace_cpu_data {
- struct list_head tcd_pages;
- unsigned long tcd_cur_pages;
-
- struct list_head tcd_daemon_pages;
- unsigned long tcd_cur_daemon_pages;
-
- unsigned long tcd_max_pages;
- int tcd_shutting_down;
- } tcd;
- char __pad[SMP_CACHE_BYTES];
-} trace_data[NR_CPUS] __cacheline_aligned;
-
-struct page_collection {
- struct list_head pc_pages;
- spinlock_t pc_lock;
- int pc_want_daemon_pages;
-};
-
-struct tracefiled_ctl {
- struct completion tctl_start;
- struct completion tctl_stop;
- wait_queue_head_t tctl_waitq;
- pid_t tctl_pid;
- atomic_t tctl_shutdown;
-};
-
-#define TRACEFILE_SIZE (500 << 20)
-static DECLARE_RWSEM(tracefile_sem);
-static char *tracefile = NULL;
-static long long tracefile_size = TRACEFILE_SIZE;
-static struct tracefiled_ctl trace_tctl;
-static DECLARE_MUTEX(trace_thread_sem);
-static int thread_running = 0;
-
-#ifndef get_cpu
-#define get_cpu() smp_processor_id()
-#define put_cpu() do { } while (0)
-#endif
-
-#define trace_get_tcd(FLAGS) ({ \
- struct trace_cpu_data *__ret; \
- int __cpu = get_cpu(); \
- local_irq_save(FLAGS); \
- __ret = &trace_data[__cpu].tcd; \
- __ret; \
-})
-
-#define trace_put_tcd(TCD, FLAGS) do { \
- local_irq_restore(FLAGS); \
- put_cpu(); \
-} while (0)
-
-static void put_pages_on_daemon_list_on_cpu(void *info);
-
-/* return a page that has 'len' bytes left at the end */
-static struct page *trace_get_page(struct trace_cpu_data *tcd,
- unsigned long len)
-{
- struct page *page = NULL;
-
- if (len > PAGE_SIZE) {
- printk(KERN_ERR "cowardly refusing to write %lu bytes in a "
- "page\n", len);
- return NULL;
- }
-
- if (!list_empty(&tcd->tcd_pages)) {
- page = list_entry(tcd->tcd_pages.prev, struct page,
- PAGE_LIST_ENTRY);
- if (page->index + len <= PAGE_SIZE)
- return page;
- }
-
- if (tcd->tcd_cur_pages < tcd->tcd_max_pages) {
- page = alloc_page(GFP_ATOMIC);
- if (page == NULL) {
- /* the kernel should print a message for us. fall back
- * to using the last page in the ring buffer. */
- goto ring_buffer;
- }
- page->index = 0;
- page->mapping = (void *)(long)smp_processor_id();
- list_add_tail(&PAGE_LIST(page), &tcd->tcd_pages);
- tcd->tcd_cur_pages++;
-
- if (tcd->tcd_cur_pages > 8 && thread_running) {
- struct tracefiled_ctl *tctl = &trace_tctl;
- wake_up(&tctl->tctl_waitq);
- }
- return page;
- }
-
- ring_buffer:
- if (thread_running) {
- int pgcount = tcd->tcd_cur_pages / 10;
- struct page_collection pc;
- struct list_head *pos, *tmp;
- printk(KERN_WARNING "debug daemon buffer overflowed; discarding"
- " 10%% of pages (%d)\n", pgcount + 1);
-
- INIT_LIST_HEAD(&pc.pc_pages);
- spin_lock_init(&pc.pc_lock);
-
- list_for_each_safe(pos, tmp, &tcd->tcd_pages) {
- struct page *page;
-
- if (pgcount-- == 0)
- break;
-
- page = list_entry(pos, struct page, PAGE_LIST_ENTRY);
- list_del(&PAGE_LIST(page));
- list_add_tail(&PAGE_LIST(page), &pc.pc_pages);
- tcd->tcd_cur_pages--;
- }
- put_pages_on_daemon_list_on_cpu(&pc);
- }
- LASSERT(!list_empty(&tcd->tcd_pages));
-
- page = list_entry(tcd->tcd_pages.next, struct page, PAGE_LIST_ENTRY);
- page->index = 0;
-
- list_del(&PAGE_LIST(page));
- list_add_tail(&PAGE_LIST(page), &tcd->tcd_pages);
- return page;
-}
-
-static void print_to_console(struct ptldebug_header *hdr, int mask, char *buf,
- int len, char *file, const char *fn)
-{
- char *prefix = NULL, *ptype = NULL;
-
- if ((mask & D_EMERG) != 0) {
- prefix = "LustreError";
- ptype = KERN_EMERG;
- } else if ((mask & D_ERROR) != 0) {
- prefix = "LustreError";
- ptype = KERN_ERR;
- } else if ((mask & D_WARNING) != 0) {
- prefix = "Lustre";
- ptype = KERN_WARNING;
- } else if (portal_printk) {
- prefix = "Lustre";
- ptype = KERN_INFO;
- }
-
- printk("%s%s: %d:%d:(%s:%d:%s()) %.*s", ptype, prefix, hdr->ph_pid,
- hdr->ph_extern_pid, file, hdr->ph_line_num, fn, len, buf);
-}
-
-void portals_debug_msg(int subsys, int mask, char *file, const char *fn,
- const int line, unsigned long stack, char *format, ...)
-{
- struct trace_cpu_data *tcd;
- struct ptldebug_header header;
- struct page *page;
- char *debug_buf = format;
- int known_size, needed = 85 /* average message length */, max_nob;
- va_list ap;
- unsigned long flags;
- struct timeval tv;
-
- if (*(format + strlen(format) - 1) != '\n')
- printk(KERN_INFO "format at %s:%d:%s doesn't end in newline\n",
- file, line, fn);
-
- tcd = trace_get_tcd(flags);
- if (tcd->tcd_shutting_down)
- goto out;
-
- do_gettimeofday(&tv);
-
- header.ph_subsys = subsys;
- header.ph_mask = mask;
- header.ph_cpu_id = smp_processor_id();
- header.ph_sec = (__u32)tv.tv_sec;
- header.ph_usec = tv.tv_usec;
- header.ph_stack = stack;
- header.ph_pid = current->pid;
- header.ph_line_num = line;
-
-#if defined(__arch_um__) && (LINUX_VERSION_CODE < KERNEL_VERSION(2,4,20))
- header.ph_extern_pid = current->thread.extern_pid;
-#elif defined(__arch_um__) && (LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0))
- header.ph_extern_pid = current->thread.mode.tt.extern_pid;
-#else
- header.ph_extern_pid = 0;
-#endif
-
- known_size = sizeof(header) + strlen(file) + strlen(fn) + 2; // nulls
-
- retry:
- page = trace_get_page(tcd, needed + known_size);
- if (page == NULL) {
- debug_buf = format;
- if (needed + known_size > PAGE_SIZE)
- mask |= D_ERROR;
- needed = strlen(format);
- goto out;
- }
-
- debug_buf = page_address(page) + page->index + known_size;
-
- max_nob = PAGE_SIZE - page->index - known_size;
- LASSERT(max_nob > 0);
- va_start(ap, format);
- needed = vsnprintf(debug_buf, max_nob, format, ap);
- va_end(ap);
-
- if (needed > max_nob) /* overflow. oh poop. */
- goto retry;
-
- header.ph_len = known_size + needed;
- debug_buf = page_address(page) + page->index;
-
- memcpy(debug_buf, &header, sizeof(header));
- page->index += sizeof(header);
- debug_buf += sizeof(header);
-
- strcpy(debug_buf, file);
- page->index += strlen(file) + 1;
- debug_buf += strlen(file) + 1;
-
- strcpy(debug_buf, fn);
- page->index += strlen(fn) + 1;
- debug_buf += strlen(fn) + 1;
-
- page->index += needed;
- if (page->index > PAGE_SIZE)
- printk(KERN_EMERG "page->index == %lu in portals_debug_msg\n",
- page->index);
-
- out:
- if ((mask & (D_EMERG | D_ERROR | D_WARNING)) || portal_printk)
- print_to_console(&header, mask, debug_buf, needed, file, fn);
-
- trace_put_tcd(tcd, flags);
-}
-EXPORT_SYMBOL(portals_debug_msg);
-
-static void collect_pages_on_cpu(void *info)
-{
- struct trace_cpu_data *tcd;
- unsigned long flags;
- struct page_collection *pc = info;
-
- tcd = trace_get_tcd(flags);
-
- spin_lock(&pc->pc_lock);
- list_splice(&tcd->tcd_pages, &pc->pc_pages);
- INIT_LIST_HEAD(&tcd->tcd_pages);
- tcd->tcd_cur_pages = 0;
- if (pc->pc_want_daemon_pages) {
- list_splice(&tcd->tcd_daemon_pages, &pc->pc_pages);
- INIT_LIST_HEAD(&tcd->tcd_daemon_pages);
- tcd->tcd_cur_daemon_pages = 0;
- }
- spin_unlock(&pc->pc_lock);
-
- trace_put_tcd(tcd, flags);
-}
-
-static void collect_pages(struct page_collection *pc)
-{
- /* needs to be fixed up for preempt */
- INIT_LIST_HEAD(&pc->pc_pages);
- collect_pages_on_cpu(pc);
- smp_call_function(collect_pages_on_cpu, pc, 0, 1);
-}
-
-static void put_pages_back_on_cpu(void *info)
-{
- struct page_collection *pc = info;
- struct trace_cpu_data *tcd;
- struct list_head *pos, *tmp, *cur_head;
- unsigned long flags;
-
- tcd = trace_get_tcd(flags);
-
- cur_head = tcd->tcd_pages.next;
-
- spin_lock(&pc->pc_lock);
- list_for_each_safe(pos, tmp, &pc->pc_pages) {
- struct page *page;
-
- page = list_entry(pos, struct page, PAGE_LIST_ENTRY);
- LASSERT(page->index <= PAGE_SIZE);
- LASSERT(page_count(page) > 0);
-
- if ((unsigned long)page->mapping != smp_processor_id())
- continue;
-
- list_del(&PAGE_LIST(page));
- list_add_tail(&PAGE_LIST(page), cur_head);
- tcd->tcd_cur_pages++;
- }
- spin_unlock(&pc->pc_lock);
-
- trace_put_tcd(tcd, flags);
-}
-
-static void put_pages_back(struct page_collection *pc)
-{
- /* needs to be fixed up for preempt */
- put_pages_back_on_cpu(pc);
- smp_call_function(put_pages_back_on_cpu, pc, 0, 1);
-}
-
-/* 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_daemon_list_on_cpu(void *info)
-{
- struct page_collection *pc = info;
- struct trace_cpu_data *tcd;
- struct list_head *pos, *tmp;
- unsigned long flags;
-
- tcd = trace_get_tcd(flags);
-
- spin_lock(&pc->pc_lock);
- list_for_each_safe(pos, tmp, &pc->pc_pages) {
- struct page *page;
-
- page = list_entry(pos, struct page, PAGE_LIST_ENTRY);
- LASSERT(page->index <= PAGE_SIZE);
- LASSERT(page_count(page) > 0);
- if ((unsigned long)page->mapping != smp_processor_id())
- continue;
-
- list_del(&PAGE_LIST(page));
- list_add_tail(&PAGE_LIST(page), &tcd->tcd_daemon_pages);
- tcd->tcd_cur_daemon_pages++;
-
- if (tcd->tcd_cur_daemon_pages > tcd->tcd_max_pages) {
- LASSERT(!list_empty(&tcd->tcd_daemon_pages));
- page = list_entry(tcd->tcd_daemon_pages.next,
- struct page, PAGE_LIST_ENTRY);
-
- LASSERT(page->index <= PAGE_SIZE);
- LASSERT(page_count(page) > 0);
-
- page->index = 0;
- list_del(&PAGE_LIST(page));
- page->mapping = NULL;
- __free_page(page);
- tcd->tcd_cur_daemon_pages--;
- }
- }
- spin_unlock(&pc->pc_lock);
-
- trace_put_tcd(tcd, flags);
-}
-
-static void put_pages_on_daemon_list(struct page_collection *pc)
-{
- put_pages_on_daemon_list_on_cpu(pc);
- smp_call_function(put_pages_on_daemon_list_on_cpu, pc, 0, 1);
-}
-
-void trace_debug_print(void)
-{
- struct page_collection pc;
- struct list_head *pos, *tmp;
-
- spin_lock_init(&pc.pc_lock);
-
- collect_pages(&pc);
- list_for_each_safe(pos, tmp, &pc.pc_pages) {
- struct page *page;
- char *p, *file, *fn;
-
- page = list_entry(pos, struct page, PAGE_LIST_ENTRY);
- LASSERT(page->index <= PAGE_SIZE);
- LASSERT(page_count(page) > 0);
-
- p = page_address(page);
- while (p < ((char *)page_address(page) + PAGE_SIZE)) {
- 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 - (p - (char *)hdr);
-
- print_to_console(hdr, D_EMERG, p, len, file, fn);
- }
-
- list_del(&PAGE_LIST(page));
- page->mapping = NULL;
- __free_page(page);
- }
-}
-
-int tracefile_dump_all_pages(char *filename)
-{
- struct page_collection pc;
- struct file *filp;
- struct list_head *pos, *tmp;
- mm_segment_t oldfs;
- int rc;
-
- down_write(&tracefile_sem);
-
- filp = filp_open(filename, O_CREAT|O_EXCL|O_WRONLY|O_LARGEFILE, 0600);
- if (IS_ERR(filp)) {
- rc = PTR_ERR(filp);
- 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 */
- oldfs = get_fs();
- set_fs(get_ds());
- list_for_each_safe(pos, tmp, &pc.pc_pages) {
- struct page *page;
-
- page = list_entry(pos, struct page, PAGE_LIST_ENTRY);
- LASSERT(page->index <= PAGE_SIZE);
- LASSERT(page_count(page) > 0);
-
- rc = filp->f_op->write(filp, page_address(page), page->index,
- &filp->f_pos);
- if (rc != page->index) {
- printk(KERN_WARNING "wanted to write %lu but wrote "
- "%d\n", page->index, rc);
- put_pages_back(&pc);
- break;
- }
- list_del(&PAGE_LIST(page));
- page->mapping = NULL;
- __free_page(page);
- }
- set_fs(oldfs);
- rc = filp->f_op->fsync(filp, filp->f_dentry, 1);
- if (rc)
- printk(KERN_ERR "sync returns %d\n", rc);
- close:
- filp_close(filp, 0);
- out:
- up_write(&tracefile_sem);
- return rc;
-}
-
-void trace_flush_pages(void)
-{
- struct page_collection pc;
- struct list_head *pos, *tmp;
-
- spin_lock_init(&pc.pc_lock);
-
- collect_pages(&pc);
- list_for_each_safe(pos, tmp, &pc.pc_pages) {
- struct page *page;
-
- page = list_entry(pos, struct page, PAGE_LIST_ENTRY);
- LASSERT(page->index <= PAGE_SIZE);
- LASSERT(page_count(page) > 0);
-
- list_del(&PAGE_LIST(page));
- page->mapping = NULL;
- __free_page(page);
- }
-}
-
-int trace_dk(struct file *file, const char *buffer, unsigned long count,
- void *data)
-{
- char *name;
- unsigned long off;
- int rc;
-
- name = kmalloc(count + 1, GFP_KERNEL);
- if (name == NULL)
- return -ENOMEM;
-
- if (copy_from_user(name, buffer, count)) {
- rc = -EFAULT;
- goto out;
- }
-
- if (name[0] != '/') {
- rc = -EINVAL;
- goto out;
- }
-
- /* be nice and strip out trailing '\n' */
- for (off = count ; off > 2 && isspace(name[off - 1]); off--)
- ;
-
- name[off] = '\0';
- rc = tracefile_dump_all_pages(name);
-out:
- if (name)
- kfree(name);
- return count;
-}
-EXPORT_SYMBOL(trace_dk);
-
-static int tracefiled(void *arg)
-{
- struct page_collection pc;
- struct tracefiled_ctl *tctl = arg;
- struct list_head *pos, *tmp;
- struct ptldebug_header *hdr;
- struct file *filp;
- struct page *page;
- mm_segment_t oldfs;
- int rc;
-
- /* 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? */
- kportal_daemonize("ktracefiled");
- reparent_to_init();
-
- spin_lock_init(&pc.pc_lock);
- complete(&tctl->tctl_start);
-
- while (1) {
- wait_queue_t __wait;
-
- init_waitqueue_entry(&__wait, current);
- add_wait_queue(&tctl->tctl_waitq, &__wait);
- set_current_state(TASK_INTERRUPTIBLE);
- schedule_timeout(HZ);
- remove_wait_queue(&tctl->tctl_waitq, &__wait);
-
- if (atomic_read(&tctl->tctl_shutdown))
- break;
-
- pc.pc_want_daemon_pages = 0;
- collect_pages(&pc);
- if (list_empty(&pc.pc_pages))
- continue;
-
- filp = NULL;
- down_read(&tracefile_sem);
- if (tracefile != NULL) {
- filp = filp_open(tracefile, O_CREAT|O_RDWR|O_LARGEFILE,
- 0600);
- if (IS_ERR(filp)) {
- printk("couldn't open %s: %ld\n", tracefile,
- PTR_ERR(filp));
- filp = NULL;
- }
- }
- up_read(&tracefile_sem);
- if (filp == NULL) {
- put_pages_on_daemon_list(&pc);
- continue;
- }
-
- oldfs = get_fs();
- set_fs(get_ds());
-
- /* mark the first header, so we can sort in chunks */
- page = list_entry(pc.pc_pages.next, struct page,
- PAGE_LIST_ENTRY);
- LASSERT(page->index <= PAGE_SIZE);
- LASSERT(page_count(page) > 0);
-
- hdr = page_address(page);
- hdr->ph_flags |= PH_FLAG_FIRST_RECORD;
-
- list_for_each_safe(pos, tmp, &pc.pc_pages) {
- static loff_t f_pos;
- page = list_entry(pos, struct page, PAGE_LIST_ENTRY);
- LASSERT(page->index <= PAGE_SIZE);
- LASSERT(page_count(page) > 0);
-
- if (f_pos >= tracefile_size)
- f_pos = 0;
- else if (f_pos > filp->f_dentry->d_inode->i_size)
- f_pos = filp->f_dentry->d_inode->i_size;
-
- rc = filp->f_op->write(filp, page_address(page),
- page->index, &f_pos);
- if (rc != page->index) {
- printk(KERN_WARNING "wanted to write %lu but "
- "wrote %d\n", page->index, rc);
- put_pages_back(&pc);
- }
- }
- set_fs(oldfs);
- filp_close(filp, 0);
-
- put_pages_on_daemon_list(&pc);
- }
- complete(&tctl->tctl_stop);
- return 0;
-}
-
-int trace_start_thread(void)
-{
- struct tracefiled_ctl *tctl = &trace_tctl;
- int rc = 0;
-
- down(&trace_thread_sem);
- 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 (kernel_thread(tracefiled, tctl, 0) < 0) {
- rc = -ECHILD;
- goto out;
- }
-
- wait_for_completion(&tctl->tctl_start);
- thread_running = 1;
-out:
- up(&trace_thread_sem);
- return rc;
-}
-
-void trace_stop_thread(void)
-{
- struct tracefiled_ctl *tctl = &trace_tctl;
-
- down(&trace_thread_sem);
- if (thread_running) {
- printk(KERN_INFO "Shutting down debug daemon thread...\n");
- atomic_set(&tctl->tctl_shutdown, 1);
- wait_for_completion(&tctl->tctl_stop);
- thread_running = 0;
- }
- up(&trace_thread_sem);
-}
-
-int trace_write_daemon_file(struct file *file, const char *buffer,
- unsigned long count, void *data)
-{
- char *name;
- unsigned long off;
- int rc;
-
- name = kmalloc(count + 1, GFP_KERNEL);
- if (name == NULL)
- return -ENOMEM;
-
- if (copy_from_user(name, buffer, count)) {
- rc = -EFAULT;
- goto out;
- }
-
- /* be nice and strip out trailing '\n' */
- for (off = count ; off > 2 && isspace(name[off - 1]); off--)
- ;
-
- name[off] = '\0';
-
- down_write(&tracefile_sem);
- if (strcmp(name, "stop") == 0) {
- tracefile = NULL;
- trace_stop_thread();
- goto out_sem;
- } else if (strncmp(name, "size=", 5) == 0) {
- tracefile_size = simple_strtoul(name + 5, NULL, 0);
- if (tracefile_size < 10 || tracefile_size > 20480)
- tracefile_size = TRACEFILE_SIZE;
- else
- tracefile_size <<= 20;
- goto out_sem;
- }
-
- if (name[0] != '/') {
- rc = -EINVAL;
- goto out_sem;
- }
-
- if (tracefile != NULL)
- kfree(tracefile);
-
- tracefile = name;
- name = NULL;
-
- printk(KERN_INFO "Lustre: debug daemon will attempt to start writing "
- "to %s (%lukB max)\n", tracefile, (long)(tracefile_size >> 10));
-
- trace_start_thread();
-
- out_sem:
- up_write(&tracefile_sem);
-
- out:
- kfree(name);
- return count;
-}
-
-int trace_read_daemon_file(char *page, char **start, off_t off, int count,
- int *eof, void *data)
-{
- int rc;
-
- down_read(&tracefile_sem);
- rc = snprintf(page, count, "%s", tracefile);
- up_read(&tracefile_sem);
-
- return rc;
-}
-
-int trace_write_debug_mb(struct file *file, const char *buffer,
- unsigned long count, void *data)
-{
- char string[32];
- int i;
- unsigned max;
-
- if (count >= sizeof(string)) {
- printk(KERN_ERR "Lustre: value too large (length %lu bytes)\n",
- count);
- return -EOVERFLOW;
- }
-
- if (copy_from_user(string, buffer, count))
- return -EFAULT;
-
- max = simple_strtoul(string, NULL, 0);
- if (max == 0)
- return -EINVAL;
-
- if (max > (num_physpages >> (20 - 2 - PAGE_SHIFT)) / 5 || max >= 512) {
- printk(KERN_ERR "Lustre: Refusing to set debug buffer size to "
- "%dMB, which is more than 80%% of available RAM (%lu)\n",
- max, (num_physpages >> (20 - 2 - PAGE_SHIFT)) / 5);
- return -EINVAL;
- }
-
- max /= smp_num_cpus;
-
- for (i = 0; i < NR_CPUS; i++) {
- struct trace_cpu_data *tcd;
- tcd = &trace_data[i].tcd;
- tcd->tcd_max_pages = max << (20 - PAGE_SHIFT);
- }
- return count;
-}
-
-int trace_read_debug_mb(char *page, char **start, off_t off, int count,
- int *eof, void *data)
-{
- struct trace_cpu_data *tcd;
- unsigned long flags;
- int rc;
-
- tcd = trace_get_tcd(flags);
- rc = snprintf(page, count, "%lu\n",
- (tcd->tcd_max_pages >> (20 - PAGE_SHIFT)) * smp_num_cpus);
- trace_put_tcd(tcd, flags);
-
- return rc;
-}
-
-int tracefile_init(void)
-{
- struct trace_cpu_data *tcd;
- int i;
-
- for (i = 0; i < NR_CPUS; i++) {
- tcd = &trace_data[i].tcd;
- INIT_LIST_HEAD(&tcd->tcd_pages);
- INIT_LIST_HEAD(&tcd->tcd_daemon_pages);
- tcd->tcd_cur_pages = 0;
- tcd->tcd_cur_daemon_pages = 0;
- tcd->tcd_max_pages = TCD_MAX_PAGES;
- tcd->tcd_shutting_down = 0;
- }
- return 0;
-}
-
-static void trace_cleanup_on_cpu(void *info)
-{
- struct trace_cpu_data *tcd;
- struct list_head *pos, *tmp;
- unsigned long flags;
-
- tcd = trace_get_tcd(flags);
-
- tcd->tcd_shutting_down = 1;
-
- list_for_each_safe(pos, tmp, &tcd->tcd_pages) {
- struct page *page;
-
- page = list_entry(pos, struct page, PAGE_LIST_ENTRY);
- LASSERT(page->index <= PAGE_SIZE);
- LASSERT(page_count(page) > 0);
-
- list_del(&PAGE_LIST(page));
- page->mapping = NULL;
- __free_page(page);
- }
- tcd->tcd_cur_pages = 0;
-
- trace_put_tcd(tcd, flags);
-}
-
-static void trace_cleanup(void)
-{
- struct page_collection pc;
-
- INIT_LIST_HEAD(&pc.pc_pages);
- spin_lock_init(&pc.pc_lock);
-
- trace_cleanup_on_cpu(&pc);
- smp_call_function(trace_cleanup_on_cpu, &pc, 0, 1);
-}
-
-void tracefile_exit(void)
-{
- trace_stop_thread();
- trace_cleanup();
-}
git://git.whamcloud.com / fs / lustre-release.git / blobdiff