klog.c revision 10673:b22eb20aa9ca 
1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21/*
22 * Copyright (c) 2008-2009, Intel Corporation.
23 * All Rights Reserved.
24 */
25
26#include <stdio.h>
27#include <stdlib.h>
28#include <memory.h>
29#include <string.h>
30#include <procfs.h>
31#include <sys/types.h>
32#include <sys/stat.h>
33#include <fcntl.h>
34#include <limits.h>
35#include <unistd.h>
36
37#include "latencytop.h"
38
39static GHashTable *proc_table = NULL; /* pid -> char * */
40static GHashTable *klog_table = NULL; /* char * -> uint64_t total */
41static char klog_filename[PATH_MAX] = DEFAULT_KLOG_FILE;
42static int klog_level = LT_KLOG_LEVEL_NONE;
43
44static void
45print_proc(void *key, const char *args, FILE *fp)
46{
47	(void) fprintf(fp, "%-8ld \"%s\"\n", (long)key, args);
48}
49
50static void
51print_stat(const char *key, lt_stat_data_t *log, FILE *fp)
52{
53	(void) fprintf(fp, "%lld, %lld, %lld, %s\n",
54	    (long long)log->lt_s_total,
55	    (long long)log->lt_s_count,
56	    (long long)log->lt_s_max,
57	    key);
58}
59
60/*
61 * Initialization for kernel logging.
62 */
63void
64lt_klog_init(void)
65{
66	if (klog_table != NULL || proc_table != NULL) {
67		return;
68	}
69
70	klog_table = g_hash_table_new_full(g_str_hash, g_str_equal,
71	    (GDestroyNotify)free, (GDestroyNotify)free);
72	lt_check_null(klog_table);
73
74	proc_table = g_hash_table_new_full(g_direct_hash, g_direct_equal,
75	    NULL, (GDestroyNotify)free);
76	lt_check_null(proc_table);
77}
78
79/*
80 * Set log file path.
81 */
82int
83lt_klog_set_log_file(const char *filename)
84{
85	FILE *fp;
86	int file_exist;
87
88	g_assert(strlen(filename) < sizeof (klog_filename));
89
90	file_exist = lt_file_exist(filename);
91	/* Test if we can write to the file */
92	fp = fopen(filename, "a");
93
94	if (fp == NULL) {
95		return (-2);
96	}
97
98	(void) fclose(fp);
99	/* Don't leave empty file around */
100	if (!file_exist) {
101		(void) unlink(filename);
102	}
103
104	(void) strncpy(klog_filename, filename,
105	    sizeof (klog_filename));
106
107	return (0);
108}
109
110/*
111 * Set log level.
112 */
113int
114lt_klog_set_log_level(int level)
115{
116	if (level < 0 || level > (int)LT_KLOG_LEVEL_ALL) {
117		return (-1);
118	}
119
120	klog_level = level;
121
122	return (0);
123}
124
125/*
126 * Write content to log file.
127 */
128void
129lt_klog_write(void)
130{
131	FILE *fp;
132	char buffer[32];
133
134	if (klog_level == LT_KLOG_LEVEL_NONE) {
135		return;
136	}
137
138	g_assert(klog_table != NULL && proc_table != NULL);
139	fp = fopen(klog_filename, "a");
140
141	if (fp == NULL) {
142		return;
143	}
144
145	lt_time_str(buffer, sizeof (buffer));
146
147	(void) fprintf(fp, "# Log generated at %s by %s\n", buffer, TITLE);
148	(void) fprintf(fp, "# List of processes\n");
149	(void) fprintf(fp, "PID, CMD\n");
150	g_hash_table_foreach(proc_table, (GHFunc)print_proc, fp);
151
152	(void) fprintf(fp, "# Statistics\n");
153	(void) fprintf(fp, "TOTAL, COUNT, MAX, PID, KSTACK\n");
154	g_hash_table_foreach(klog_table, (GHFunc)print_stat, fp);
155
156	(void) fclose(fp);
157}
158
159/*
160 * Clean up. It flushes all log content in memory to log file.
161 */
162void
163lt_klog_deinit(void)
164{
165	if (klog_table != NULL) {
166		g_hash_table_destroy(klog_table);
167		klog_table = NULL;
168	}
169
170	if (proc_table != NULL) {
171		g_hash_table_destroy(proc_table);
172		proc_table = NULL;
173	}
174}
175
176/*
177 * Write a kernel stack and its statistics to log file. Only "total" will
178 * be logged, others are internally discarded.
179 */
180/* ARGSUSED */
181void
182lt_klog_log(int level, pid_t pid, char *stack,
183	lt_stat_type_t type, uint64_t value)
184{
185	lt_stat_data_t *entry = NULL;
186	char *psargs;
187	char *str;
188	int str_len;
189
190	if ((level & klog_level) == 0) {
191		return;
192	}
193
194	g_assert(klog_table != NULL && proc_table != NULL);
195	psargs = (char *)g_hash_table_lookup(proc_table,
196	    LT_INT_TO_POINTER(pid));
197
198	if (psargs == NULL) {
199		psargs = lt_get_proc_field(pid, LT_FIELD_PSARGS);
200
201		if (psargs == NULL) {
202			psargs = lt_get_proc_field(pid, LT_FIELD_FNAME);
203		}
204
205		if (psargs == NULL) {
206			return;
207		}
208
209		g_hash_table_insert(proc_table,
210		    LT_INT_TO_POINTER(pid), psargs);
211	}
212
213	str_len = strlen(stack) + 20;
214	str = lt_malloc(str_len);
215	(void) snprintf(str, str_len, "%ld, \"%s\"", pid, stack);
216	entry = (lt_stat_data_t *)g_hash_table_lookup(klog_table, str);
217
218	if (entry == NULL) {
219		entry = (lt_stat_data_t *)lt_zalloc(sizeof (lt_stat_data_t));
220		g_hash_table_insert(klog_table, str, entry);
221	} else {
222		free(str);
223	}
224
225	lt_update_stat_value(entry, type, value);
226}
227