1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
2 * vim:expandtab:shiftwidth=8:tabstop=8:
6 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 only,
10 * as published by the Free Software Foundation.
12 * This program is distributed in the hope that it will be useful, but
13 * WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * General Public License version 2 for more details (a copy is included
16 * in the LICENSE file that accompanied this code).
18 * You should have received a copy of the GNU General Public License
19 * version 2 along with this program; If not, see
20 * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
22 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
23 * CA 95054 USA or visit www.sun.com if you need additional information or
29 * Copyright 2008 Sun Microsystems, Inc. All rights reserved
30 * Use is subject to license terms.
33 * This file is part of Lustre, http://www.lustre.org/
34 * Lustre is a trademark of Sun Microsystems, Inc.
38 * Author: Eric Barton <eeb@clusterfs.com>
42 # define EXPORT_SYMTAB
45 #define DEBUG_SUBSYSTEM S_LNET
47 #include <libcfs/libcfs.h>
53 lwt_cpu_t lwt_cpus[NR_CPUS];
56 int lwt_pages_per_cpu;
58 /* NB only root is allowed to retrieve LWT info; it's an open door into the
62 lwt_lookup_string (int *size, char *knl_ptr,
63 char *user_ptr, int user_size)
67 /* knl_ptr was retrieved from an LWT snapshot and the caller wants to
68 * turn it into a string. NB we can crash with an access violation
69 * trying to determine the string length, so we're trusting our
72 if (!cfs_capable(CFS_CAP_SYS_ADMIN))
79 *size = strnlen (knl_ptr, maxsize - 1) + 1;
81 if (user_ptr != NULL) {
85 if (copy_to_user (user_ptr, knl_ptr, *size))
88 /* Did I truncate the string? */
89 if (knl_ptr[*size - 1] != 0)
90 copy_to_user (user_ptr + *size - 4, "...", 4);
97 lwt_control (int enable, int clear)
103 if (!cfs_capable(CFS_CAP_SYS_ADMIN))
110 /* give people some time to stop adding traces */
111 schedule_timeout(10);
114 for (i = 0; i < num_online_cpus(); i++) {
115 p = lwt_cpus[i].lwtc_current_page;
123 for (j = 0; j < lwt_pages_per_cpu; j++) {
124 memset (p->lwtp_events, 0, CFS_PAGE_SIZE);
126 p = list_entry (p->lwtp_list.next,
127 lwt_page_t, lwtp_list);
141 lwt_snapshot (cycles_t *now, int *ncpu, int *total_size,
142 void *user_ptr, int user_size)
144 const int events_per_page = CFS_PAGE_SIZE / sizeof(lwt_event_t);
145 const int bytes_per_page = events_per_page * sizeof(lwt_event_t);
150 if (!cfs_capable(CFS_CAP_SYS_ADMIN))
153 *ncpu = num_online_cpus();
154 *total_size = num_online_cpus() * lwt_pages_per_cpu * bytes_per_page;
157 if (user_ptr == NULL)
160 for (i = 0; i < num_online_cpus(); i++) {
161 p = lwt_cpus[i].lwtc_current_page;
166 for (j = 0; j < lwt_pages_per_cpu; j++) {
167 if (copy_to_user(user_ptr, p->lwtp_events,
171 user_ptr = ((char *)user_ptr) + bytes_per_page;
172 p = list_entry(p->lwtp_list.next,
173 lwt_page_t, lwtp_list);
187 for (i = 0; i < num_online_cpus(); i++)
188 if (lwt_cpus[i].lwtc_current_page != NULL)
191 LASSERT (!lwt_enabled);
193 /* NULL pointers, zero scalars */
194 memset (lwt_cpus, 0, sizeof (lwt_cpus));
195 lwt_pages_per_cpu = LWT_MEMORY / (num_online_cpus() * CFS_PAGE_SIZE);
197 for (i = 0; i < num_online_cpus(); i++)
198 for (j = 0; j < lwt_pages_per_cpu; j++) {
199 struct page *page = alloc_page (GFP_KERNEL);
203 CERROR ("Can't allocate page\n");
208 LIBCFS_ALLOC(lwtp, sizeof (*lwtp));
210 CERROR ("Can't allocate lwtp\n");
216 lwtp->lwtp_page = page;
217 lwtp->lwtp_events = page_address(page);
218 memset (lwtp->lwtp_events, 0, CFS_PAGE_SIZE);
221 INIT_LIST_HEAD (&lwtp->lwtp_list);
222 lwt_cpus[i].lwtc_current_page = lwtp;
224 list_add (&lwtp->lwtp_list,
225 &lwt_cpus[i].lwtc_current_page->lwtp_list);
244 for (i = 0; i < num_online_cpus(); i++)
245 while (lwt_cpus[i].lwtc_current_page != NULL) {
246 lwt_page_t *lwtp = lwt_cpus[i].lwtc_current_page;
248 if (list_empty (&lwtp->lwtp_list)) {
249 lwt_cpus[i].lwtc_current_page = NULL;
251 lwt_cpus[i].lwtc_current_page =
252 list_entry (lwtp->lwtp_list.next,
253 lwt_page_t, lwtp_list);
255 list_del (&lwtp->lwtp_list);
258 __free_page (lwtp->lwtp_page);
259 LIBCFS_FREE (lwtp, sizeof (*lwtp));
263 EXPORT_SYMBOL(lwt_enabled);
264 EXPORT_SYMBOL(lwt_cpus);
266 EXPORT_SYMBOL(lwt_init);
267 EXPORT_SYMBOL(lwt_fini);
268 EXPORT_SYMBOL(lwt_lookup_string);
269 EXPORT_SYMBOL(lwt_control);
270 EXPORT_SYMBOL(lwt_snapshot);