Loading...
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 | /*
* Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
* All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it would 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 this program; if not, write the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <xfs.h>
static kmem_zone_t *ktrace_hdr_zone;
static kmem_zone_t *ktrace_ent_zone;
static int ktrace_zentries;
void __init
ktrace_init(int zentries)
{
ktrace_zentries = roundup_pow_of_two(zentries);
ktrace_hdr_zone = kmem_zone_init(sizeof(ktrace_t),
"ktrace_hdr");
ASSERT(ktrace_hdr_zone);
ktrace_ent_zone = kmem_zone_init(ktrace_zentries
* sizeof(ktrace_entry_t),
"ktrace_ent");
ASSERT(ktrace_ent_zone);
}
void __exit
ktrace_uninit(void)
{
kmem_zone_destroy(ktrace_hdr_zone);
kmem_zone_destroy(ktrace_ent_zone);
}
/*
* ktrace_alloc()
*
* Allocate a ktrace header and enough buffering for the given
* number of entries. Round the number of entries up to a
* power of 2 so we can do fast masking to get the index from
* the atomic index counter.
*/
ktrace_t *
ktrace_alloc(int nentries, unsigned int __nocast sleep)
{
ktrace_t *ktp;
ktrace_entry_t *ktep;
int entries;
ktp = (ktrace_t*)kmem_zone_alloc(ktrace_hdr_zone, sleep);
if (ktp == (ktrace_t*)NULL) {
/*
* KM_SLEEP callers don't expect failure.
*/
if (sleep & KM_SLEEP)
panic("ktrace_alloc: NULL memory on KM_SLEEP request!");
return NULL;
}
/*
* Special treatment for buffers with the ktrace_zentries entries
*/
entries = roundup_pow_of_two(nentries);
if (entries == ktrace_zentries) {
ktep = (ktrace_entry_t*)kmem_zone_zalloc(ktrace_ent_zone,
sleep);
} else {
ktep = (ktrace_entry_t*)kmem_zalloc((entries * sizeof(*ktep)),
sleep | KM_LARGE);
}
if (ktep == NULL) {
/*
* KM_SLEEP callers don't expect failure.
*/
if (sleep & KM_SLEEP)
panic("ktrace_alloc: NULL memory on KM_SLEEP request!");
kmem_free(ktp);
return NULL;
}
ktp->kt_entries = ktep;
ktp->kt_nentries = entries;
ASSERT(is_power_of_2(entries));
ktp->kt_index_mask = entries - 1;
atomic_set(&ktp->kt_index, 0);
ktp->kt_rollover = 0;
return ktp;
}
/*
* ktrace_free()
*
* Free up the ktrace header and buffer. It is up to the caller
* to ensure that no-one is referencing it.
*/
void
ktrace_free(ktrace_t *ktp)
{
if (ktp == (ktrace_t *)NULL)
return;
/*
* Special treatment for the Vnode trace buffer.
*/
if (ktp->kt_nentries == ktrace_zentries)
kmem_zone_free(ktrace_ent_zone, ktp->kt_entries);
else
kmem_free(ktp->kt_entries);
kmem_zone_free(ktrace_hdr_zone, ktp);
}
/*
* Enter the given values into the "next" entry in the trace buffer.
* kt_index is always the index of the next entry to be filled.
*/
void
ktrace_enter(
ktrace_t *ktp,
void *val0,
void *val1,
void *val2,
void *val3,
void *val4,
void *val5,
void *val6,
void *val7,
void *val8,
void *val9,
void *val10,
void *val11,
void *val12,
void *val13,
void *val14,
void *val15)
{
int index;
ktrace_entry_t *ktep;
ASSERT(ktp != NULL);
/*
* Grab an entry by pushing the index up to the next one.
*/
index = atomic_add_return(1, &ktp->kt_index);
index = (index - 1) & ktp->kt_index_mask;
if (!ktp->kt_rollover && index == ktp->kt_nentries - 1)
ktp->kt_rollover = 1;
ASSERT((index >= 0) && (index < ktp->kt_nentries));
ktep = &(ktp->kt_entries[index]);
ktep->val[0] = val0;
ktep->val[1] = val1;
ktep->val[2] = val2;
ktep->val[3] = val3;
ktep->val[4] = val4;
ktep->val[5] = val5;
ktep->val[6] = val6;
ktep->val[7] = val7;
ktep->val[8] = val8;
ktep->val[9] = val9;
ktep->val[10] = val10;
ktep->val[11] = val11;
ktep->val[12] = val12;
ktep->val[13] = val13;
ktep->val[14] = val14;
ktep->val[15] = val15;
}
/*
* Return the number of entries in the trace buffer.
*/
int
ktrace_nentries(
ktrace_t *ktp)
{
int index;
if (ktp == NULL)
return 0;
index = atomic_read(&ktp->kt_index) & ktp->kt_index_mask;
return (ktp->kt_rollover ? ktp->kt_nentries : index);
}
/*
* ktrace_first()
*
* This is used to find the start of the trace buffer.
* In conjunction with ktrace_next() it can be used to
* iterate through the entire trace buffer. This code does
* not do any locking because it is assumed that it is called
* from the debugger.
*
* The caller must pass in a pointer to a ktrace_snap
* structure in which we will keep some state used to
* iterate through the buffer. This state must not touched
* by any code outside of this module.
*/
ktrace_entry_t *
ktrace_first(ktrace_t *ktp, ktrace_snap_t *ktsp)
{
ktrace_entry_t *ktep;
int index;
int nentries;
if (ktp->kt_rollover)
index = atomic_read(&ktp->kt_index) & ktp->kt_index_mask;
else
index = 0;
ktsp->ks_start = index;
ktep = &(ktp->kt_entries[index]);
nentries = ktrace_nentries(ktp);
index++;
if (index < nentries) {
ktsp->ks_index = index;
} else {
ktsp->ks_index = 0;
if (index > nentries)
ktep = NULL;
}
return ktep;
}
/*
* ktrace_next()
*
* This is used to iterate through the entries of the given
* trace buffer. The caller must pass in the ktrace_snap_t
* structure initialized by ktrace_first(). The return value
* will be either a pointer to the next ktrace_entry or NULL
* if all of the entries have been traversed.
*/
ktrace_entry_t *
ktrace_next(
ktrace_t *ktp,
ktrace_snap_t *ktsp)
{
int index;
ktrace_entry_t *ktep;
index = ktsp->ks_index;
if (index == ktsp->ks_start) {
ktep = NULL;
} else {
ktep = &ktp->kt_entries[index];
}
index++;
if (index == ktrace_nentries(ktp)) {
ktsp->ks_index = 0;
} else {
ktsp->ks_index = index;
}
return ktep;
}
/*
* ktrace_skip()
*
* Skip the next "count" entries and return the entry after that.
* Return NULL if this causes us to iterate past the beginning again.
*/
ktrace_entry_t *
ktrace_skip(
ktrace_t *ktp,
int count,
ktrace_snap_t *ktsp)
{
int index;
int new_index;
ktrace_entry_t *ktep;
int nentries = ktrace_nentries(ktp);
index = ktsp->ks_index;
new_index = index + count;
while (new_index >= nentries) {
new_index -= nentries;
}
if (index == ktsp->ks_start) {
/*
* We've iterated around to the start, so we're done.
*/
ktep = NULL;
} else if ((new_index < index) && (index < ktsp->ks_index)) {
/*
* We've skipped past the start again, so we're done.
*/
ktep = NULL;
ktsp->ks_index = ktsp->ks_start;
} else {
ktep = &(ktp->kt_entries[new_index]);
new_index++;
if (new_index == nentries) {
ktsp->ks_index = 0;
} else {
ktsp->ks_index = new_index;
}
}
return ktep;
}
|