2 * Copyright (c) 2000 John Baldwin <jhb@FreeBSD.org>
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of the author nor the names of any co-contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * This module holds the global variables used by KTR and the ktr_tracepoint()
32 * function that does the actual tracing.
35 #include <sys/cdefs.h>
36 __FBSDID("$FreeBSD$");
42 #include <sys/param.h>
43 #include <sys/queue.h>
46 #include <sys/cpuset.h>
47 #include <sys/kernel.h>
49 #include <sys/libkern.h>
51 #include <sys/malloc.h>
52 #include <sys/mutex.h>
55 #include <sys/sysctl.h>
56 #include <sys/systm.h>
59 #include <machine/cpu.h>
61 #include <machine/ktr.h>
66 #include <ddb/db_output.h>
70 #define KTR_ENTRIES 1024
73 /* Limit the allocations to something manageable. */
74 #define KTR_ENTRIES_MAX (8 * 1024 * 1024)
81 #define KTR_CPUMASK CPUSET_FSET
85 #define KTR_TIME get_cyclecount()
89 #define KTR_CPU PCPU_GET(cpuid)
92 static MALLOC_DEFINE(M_KTR, "KTR", "KTR");
94 FEATURE(ktr, "Kernel support for KTR kernel tracing facility");
96 volatile int ktr_idx = 0;
97 int ktr_mask = KTR_MASK;
98 int ktr_compile = KTR_COMPILE;
99 int ktr_entries = KTR_ENTRIES;
100 int ktr_version = KTR_VERSION;
101 struct ktr_entry ktr_buf_init[KTR_ENTRIES];
102 struct ktr_entry *ktr_buf = ktr_buf_init;
103 cpuset_t ktr_cpumask = CPUSET_T_INITIALIZER(KTR_CPUMASK);
104 static char ktr_cpumask_str[CPUSETBUFSIZ];
106 TUNABLE_INT("debug.ktr.mask", &ktr_mask);
108 TUNABLE_STR("debug.ktr.cpumask", ktr_cpumask_str, sizeof(ktr_cpumask_str));
110 static SYSCTL_NODE(_debug, OID_AUTO, ktr, CTLFLAG_RD, 0, "KTR options");
112 SYSCTL_INT(_debug_ktr, OID_AUTO, version, CTLFLAG_RD,
113 &ktr_version, 0, "Version of the KTR interface");
115 SYSCTL_UINT(_debug_ktr, OID_AUTO, compile, CTLFLAG_RD,
116 &ktr_compile, 0, "Bitmask of KTR event classes compiled into the kernel");
119 ktr_cpumask_initializer(void *dummy __unused)
123 * TUNABLE_STR() runs with SI_ORDER_MIDDLE priority, thus it must be
124 * already set, if necessary.
126 if (ktr_cpumask_str[0] != '\0' &&
127 cpusetobj_strscan(&ktr_cpumask, ktr_cpumask_str) == -1)
128 CPU_FILL(&ktr_cpumask);
130 SYSINIT(ktr_cpumask_initializer, SI_SUB_TUNABLES, SI_ORDER_ANY,
131 ktr_cpumask_initializer, NULL);
134 sysctl_debug_ktr_cpumask(SYSCTL_HANDLER_ARGS)
136 char lktr_cpumask_str[CPUSETBUFSIZ];
140 cpusetobj_strprint(lktr_cpumask_str, &ktr_cpumask);
141 error = sysctl_handle_string(oidp, lktr_cpumask_str,
142 sizeof(lktr_cpumask_str), req);
143 if (error != 0 || req->newptr == NULL)
145 if (cpusetobj_strscan(&imask, lktr_cpumask_str) == -1)
147 CPU_COPY(&imask, &ktr_cpumask);
151 SYSCTL_PROC(_debug_ktr, OID_AUTO, cpumask,
152 CTLFLAG_RW | CTLFLAG_MPSAFE | CTLTYPE_STRING, NULL, 0,
153 sysctl_debug_ktr_cpumask, "S",
154 "Bitmask of CPUs on which KTR logging is enabled");
157 sysctl_debug_ktr_clear(SYSCTL_HANDLER_ARGS)
162 error = sysctl_handle_int(oidp, &clear, 0, req);
163 if (error || !req->newptr)
167 bzero(ktr_buf, sizeof(*ktr_buf) * ktr_entries);
173 SYSCTL_PROC(_debug_ktr, OID_AUTO, clear, CTLTYPE_INT|CTLFLAG_RW, 0, 0,
174 sysctl_debug_ktr_clear, "I", "Clear KTR Buffer");
177 * This is a sysctl proc so that it is serialized as !MPSAFE along with
178 * the other ktr sysctl procs.
181 sysctl_debug_ktr_mask(SYSCTL_HANDLER_ARGS)
186 error = sysctl_handle_int(oidp, &mask, 0, req);
187 if (error || !req->newptr)
193 SYSCTL_PROC(_debug_ktr, OID_AUTO, mask, CTLTYPE_UINT|CTLFLAG_RW, 0, 0,
194 sysctl_debug_ktr_mask, "IU",
195 "Bitmask of KTR event classes for which logging is enabled");
198 sysctl_debug_ktr_entries(SYSCTL_HANDLER_ARGS)
200 int entries, error, mask;
201 struct ktr_entry *buf, *oldbuf;
203 entries = ktr_entries;
204 error = sysctl_handle_int(oidp, &entries, 0, req);
205 if (error || !req->newptr)
207 if (entries > KTR_ENTRIES_MAX)
209 /* Disable ktr temporarily. */
211 atomic_store_rel_int(&ktr_mask, 0);
212 /* Wait for threads to go idle. */
213 if ((error = quiesce_all_cpus("ktrent", PCATCH)) != 0) {
217 if (ktr_buf != ktr_buf_init)
221 /* Allocate a new buffer. */
222 buf = malloc(sizeof(*buf) * entries, M_KTR, M_WAITOK | M_ZERO);
223 /* Install the new buffer and restart ktr. */
225 ktr_entries = entries;
227 atomic_store_rel_int(&ktr_mask, mask);
234 SYSCTL_PROC(_debug_ktr, OID_AUTO, entries, CTLTYPE_INT|CTLFLAG_RW, 0, 0,
235 sysctl_debug_ktr_entries, "I", "Number of entries in the KTR buffer");
238 int ktr_verbose = KTR_VERBOSE;
239 TUNABLE_INT("debug.ktr.verbose", &ktr_verbose);
240 SYSCTL_INT(_debug_ktr, OID_AUTO, verbose, CTLFLAG_RW, &ktr_verbose, 0, "");
245 char ktr_alq_file[MAXPATHLEN] = "/tmp/ktr.out";
247 int ktr_alq_depth = KTR_ENTRIES;
248 int ktr_alq_enabled = 0;
249 int ktr_alq_failed = 0;
252 SYSCTL_INT(_debug_ktr, OID_AUTO, alq_max, CTLFLAG_RW, &ktr_alq_max, 0,
253 "Maximum number of entries to write");
254 SYSCTL_INT(_debug_ktr, OID_AUTO, alq_cnt, CTLFLAG_RD, &ktr_alq_cnt, 0,
255 "Current number of written entries");
256 SYSCTL_INT(_debug_ktr, OID_AUTO, alq_failed, CTLFLAG_RD, &ktr_alq_failed, 0,
257 "Number of times we overran the buffer");
258 SYSCTL_INT(_debug_ktr, OID_AUTO, alq_depth, CTLFLAG_RW, &ktr_alq_depth, 0,
259 "Number of items in the write buffer");
260 SYSCTL_STRING(_debug_ktr, OID_AUTO, alq_file, CTLFLAG_RW, ktr_alq_file,
261 sizeof(ktr_alq_file), "KTR logging file");
264 sysctl_debug_ktr_alq_enable(SYSCTL_HANDLER_ARGS)
269 enable = ktr_alq_enabled;
271 error = sysctl_handle_int(oidp, &enable, 0, req);
272 if (error || !req->newptr)
278 error = alq_open(&ktr_alq, (const char *)ktr_alq_file,
279 req->td->td_ucred, ALQ_DEFAULT_CMODE,
280 sizeof(struct ktr_entry), ktr_alq_depth);
287 if (ktr_alq_enabled == 0)
296 SYSCTL_PROC(_debug_ktr, OID_AUTO, alq_enable,
297 CTLTYPE_INT|CTLFLAG_RW, 0, 0, sysctl_debug_ktr_alq_enable,
298 "I", "Enable KTR logging");
302 ktr_tracepoint(u_int mask, const char *file, int line, const char *format,
303 u_long arg1, u_long arg2, u_long arg3, u_long arg4, u_long arg5,
306 struct ktr_entry *entry;
308 struct ale *ale = NULL;
310 int newindex, saveindex;
311 #if defined(KTR_VERBOSE) || defined(KTR_ALQ)
318 if ((ktr_mask & mask) == 0 || ktr_buf == NULL)
321 if (!CPU_ISSET(cpu, &ktr_cpumask))
323 #if defined(KTR_VERBOSE) || defined(KTR_ALQ)
325 if (td->td_pflags & TDP_INKTR)
327 td->td_pflags |= TDP_INKTR;
330 if (ktr_alq_enabled) {
331 if (td->td_critnest == 0 &&
332 (td->td_flags & TDF_IDLETD) == 0 &&
334 if (ktr_alq_max && ktr_alq_cnt > ktr_alq_max)
336 if ((ale = alq_get(ktr_alq, ALQ_NOWAIT)) == NULL) {
341 entry = (struct ktr_entry *)ale->ae_data;
350 newindex = (saveindex + 1) % ktr_entries;
351 } while (atomic_cmpset_rel_int(&ktr_idx, saveindex, newindex) == 0);
352 entry = &ktr_buf[saveindex];
354 entry->ktr_timestamp = KTR_TIME;
355 entry->ktr_cpu = cpu;
356 entry->ktr_thread = curthread;
358 while (strncmp(file, "../", 3) == 0)
360 entry->ktr_file = file;
361 entry->ktr_line = line;
365 printf("cpu%d ", cpu);
367 if (ktr_verbose > 1) {
368 printf("%s.%d\t", entry->ktr_file,
371 printf(format, arg1, arg2, arg3, arg4, arg5, arg6);
375 entry->ktr_desc = format;
376 entry->ktr_parms[0] = arg1;
377 entry->ktr_parms[1] = arg2;
378 entry->ktr_parms[2] = arg3;
379 entry->ktr_parms[3] = arg4;
380 entry->ktr_parms[4] = arg5;
381 entry->ktr_parms[5] = arg6;
383 if (ktr_alq_enabled && ale)
384 alq_post(ktr_alq, ale);
387 #if defined(KTR_VERBOSE) || defined(KTR_ALQ)
388 td->td_pflags &= ~TDP_INKTR;
398 static struct tstate tstate;
399 static int db_ktr_verbose;
400 static int db_mach_vtrace(void);
402 DB_SHOW_COMMAND(ktr, db_ktr_all)
405 tstate.cur = (ktr_idx - 1) % ktr_entries;
408 db_ktr_verbose |= (strchr(modif, 'v') != NULL) ? 2 : 0;
409 db_ktr_verbose |= (strchr(modif, 'V') != NULL) ? 1 : 0; /* just timestap please */
410 if (strchr(modif, 'a') != NULL) {
412 while (cncheckc() != -1)
413 if (db_mach_vtrace() == 0)
416 while (!db_pager_quit)
417 if (db_mach_vtrace() == 0)
425 struct ktr_entry *kp;
427 if (tstate.cur == tstate.first || ktr_buf == NULL) {
428 db_printf("--- End of trace buffer ---\n");
431 kp = &ktr_buf[tstate.cur];
433 /* Skip over unused entries. */
434 if (kp->ktr_desc == NULL) {
435 db_printf("--- End of trace buffer ---\n");
438 db_printf("%d (%p", tstate.cur, kp->ktr_thread);
440 db_printf(":cpu%d", kp->ktr_cpu);
443 if (db_ktr_verbose >= 1) {
444 db_printf(" %10.10lld", (long long)kp->ktr_timestamp);
446 if (db_ktr_verbose >= 2) {
447 db_printf(" %s.%d", kp->ktr_file, kp->ktr_line);
450 db_printf(kp->ktr_desc, kp->ktr_parms[0], kp->ktr_parms[1],
451 kp->ktr_parms[2], kp->ktr_parms[3], kp->ktr_parms[4],
455 if (tstate.first == -1)
456 tstate.first = tstate.cur;
458 if (--tstate.cur < 0)
459 tstate.cur = ktr_entries - 1;