blktrace: don't stop tracer if not setup trace successfully
[blktrace.git] / btt / seek.c
CommitLineData
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1/*
2 * blktrace output analysis: generate a timeline & gather statistics
3 *
4 * Copyright (C) 2006 Alan D. Brunelle <Alan.Brunelle@hp.com>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 *
20 */
5bebfd16 21#include <float.h>
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22#include "globals.h"
23
24struct seek_bkt {
6eb42155 25 struct rb_node rb_node;
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26 long long sectors;
27 int nseeks;
28};
29
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30/* Seeks per second */
31struct sps_bkt {
32 double t_start, t_last;
33 unsigned long nseeks;
34};
35
5225e788 36struct seeki {
ccf6d55e 37 FILE *rfp, *wfp, *cfp, *sps_fp;
6eb42155 38 struct rb_root root;
ccf6d55e 39 struct sps_bkt sps;
6eb42155 40 long long tot_seeks;
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41 double total_sectors;
42 long long last_start, last_end;
43};
44
4c48f14e 45static FILE *seek_open(char *str, char rw)
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46{
47 FILE *fp;
48 char *oname;
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49
50 if (seek_name == NULL) return NULL;
51
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52 oname = malloc(strlen(seek_name) + strlen(str) + 32);
53 sprintf(oname, "%s_%s_%c.dat", seek_name, str, rw);
84b321fa 54 if ((fp = my_fopen(oname, "w")) == NULL) {
5225e788 55 perror(oname);
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56 free(oname);
57 } else
c053af42 58 add_file(fp, oname);
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59
60 return fp;
61}
62
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63static void __insert(struct rb_root *root, long long sectors)
64{
65 struct seek_bkt *sbp;
66 struct rb_node *parent = NULL;
67 struct rb_node **p = &root->rb_node;
68
69 while (*p) {
70 parent = *p;
71 sbp = rb_entry(parent, struct seek_bkt, rb_node);
72 if (sectors < sbp->sectors)
73 p = &(*p)->rb_left;
74 else if (sectors > sbp->sectors)
75 p = &(*p)->rb_right;
76 else {
77 sbp->nseeks++;
78 return;
79 }
80 }
81
82 sbp = malloc(sizeof(struct seek_bkt));
83 sbp->nseeks = 1;
84 sbp->sectors = sectors;
85
86 rb_link_node(&sbp->rb_node, parent, p);
87 rb_insert_color(&sbp->rb_node, root);
88}
89
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90static void __destroy(struct rb_node *n)
91{
92 if (n) {
93 struct seek_bkt *sbp = rb_entry(n, struct seek_bkt, rb_node);
94
95 __destroy(n->rb_left);
96 __destroy(n->rb_right);
97 free(sbp);
98 }
99}
100
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101static void sps_emit(struct seeki *sip)
102{
f6d38abd 103 double s_p_s;
ccf6d55e 104 struct sps_bkt *sps = &sip->sps;
5bebfd16 105 double delta = sps->t_last - sps->t_start;
ccf6d55e 106
f6d38abd 107 if ((sps->nseeks == 1) || (delta < DBL_EPSILON))
5bebfd16 108 s_p_s = (double)(sps->nseeks);
f6d38abd 109 else
ccf6d55e 110 s_p_s = (double)(sps->nseeks) / delta;
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111
112 fprintf(sip->sps_fp, "%15.9lf %.2lf\n", sps->t_start, s_p_s);
113
114 sps->t_start = 0;
115 sps->nseeks = 0;
116}
117
118static void sps_add(struct seeki *sip, double t)
119{
120 if (sip->sps_fp) {
121 struct sps_bkt *sps = &sip->sps;
122
123 if (sps->nseeks != 0 && ((t - sps->t_start) >= 1.0))
124 sps_emit(sip);
125
126 sps->t_last = t;
127 if (sps->nseeks == 0) {
128 sps->t_start = t;
129 sps->nseeks = 1;
c053af42 130 } else
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131 sps->nseeks++;
132 }
133}
134
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135static int __median(struct rb_node *n, long long sofar, long long target,
136 long long *rvp)
b2ecdd0f 137{
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138 struct seek_bkt *sbp;
139
140 sbp = rb_entry(n, struct seek_bkt, rb_node);
141 if ((sofar + sbp->nseeks) >= target) {
142 *rvp = sbp->sectors;
143 return 1;
144 }
145
146 if (n->rb_left && __median(n->rb_left, sofar, target, rvp))
147 return 1;
148
149 if (n->rb_right && __median(n->rb_right, sofar, target, rvp))
150 return 1;
151
152 return 0;
153
154}
155
156static void __mode(struct rb_node *n, struct mode *mp)
157{
158 struct seek_bkt *sbp;
159
160 if (n->rb_left)
161 __mode(n->rb_left, mp);
162 if (n->rb_right)
163 __mode(n->rb_right, mp);
164
165 sbp = rb_entry(n, struct seek_bkt, rb_node);
166 if (mp->modes == NULL) {
167 mp->modes = malloc(sizeof(long long));
168 mp->nmds = 0;
169 } else if (sbp->nseeks > mp->most_seeks)
170 mp->nmds = 0;
171 else if (sbp->nseeks == mp->most_seeks)
172 mp->modes = realloc(mp->modes, (mp->nmds + 1) *
173 sizeof(long long));
174 else
175 return;
176
177 mp->most_seeks = sbp->nseeks;
178 mp->modes[mp->nmds++] = sbp->sectors;
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179}
180
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181long long seek_dist(struct seeki *sip, struct io *iop)
182{
183 long long dist;
184 long long start = BIT_START(iop), end = BIT_END(iop);
185
69040794 186 if (seek_absolute)
5225e788 187 dist = start - sip->last_end;
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188 else {
189 /* Some overlap means no seek */
190 if (((sip->last_start <= start) && (start <= sip->last_end)) ||
191 ((sip->last_start <= end) && (end <= sip->last_end)))
192 dist = 0;
193 else if (start > sip->last_end)
194 dist = start - sip->last_end;
195 else
196 dist = start - sip->last_start;
197
198 }
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199
200 sip->last_start = start;
201 sip->last_end = end;
202 return dist;
203}
204
a155ab98 205void *seeki_alloc(struct d_info *dip, char *post)
5225e788 206{
a155ab98 207 char str[256];
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208 struct seeki *sip = malloc(sizeof(struct seeki));
209
a155ab98 210 sprintf(str, "%s%s", dip->dip_name, post);
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211 sip->rfp = seek_open(str, 'r');
212 sip->wfp = seek_open(str, 'w');
213 sip->cfp = seek_open(str, 'c');
6eb42155 214 sip->tot_seeks = 0;
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215 sip->total_sectors = 0.0;
216 sip->last_start = sip->last_end = 0;
6eb42155 217 memset(&sip->root, 0, sizeof(sip->root));
5225e788 218
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219 if (sps_name) {
220 char *oname;
221
222 memset(&sip->sps, 0, sizeof(sip->sps));
223
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224 oname = malloc(strlen(sps_name) + strlen(dip->dip_name) + 32);
225 sprintf(oname, "%s_%s.dat", sps_name, dip->dip_name);
84b321fa 226 if ((sip->sps_fp = my_fopen(oname, "w")) == NULL) {
ccf6d55e 227 perror(oname);
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228 free(oname);
229 } else
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230 add_file(sip->sps_fp, oname);
231 } else
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232 sip->sps_fp = NULL;
233
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234 return sip;
235}
236
c053af42 237void seeki_free(void *param)
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238{
239 struct seeki *sip = param;
240
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241 if (sip->sps_fp && sip->sps.nseeks != 0)
242 sps_emit(sip);
243
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244 /*
245 * Associated files are cleaned up by seek_clean
246 */
247 __destroy(sip->root.rb_node);
248 free(sip);
249}
250
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251void seeki_add(void *handle, struct io *iop)
252{
5225e788 253 struct seeki *sip = handle;
69040794 254 char rw = IOP_READ(iop) ? 'r' : 'w';
5225e788 255 long long dist = seek_dist(sip, iop);
69040794 256 double tstamp = BIT_TIME(iop->t.time);
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257 FILE *fp = IOP_READ(iop) ? sip->rfp : sip->wfp;
258
259 if (fp)
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260 fprintf(fp, "%15.9lf %13lld %c\n", tstamp, dist, rw);
261 if (sip->cfp)
262 fprintf(sip->cfp, "%15.9lf %13lld %c\n", tstamp, dist, rw);
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263
264 dist = llabs(dist);
6eb42155 265 sip->tot_seeks++;
5225e788 266 sip->total_sectors += dist;
6eb42155 267 __insert(&sip->root, dist);
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268
269 sps_add(sip, tstamp);
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270}
271
272long long seeki_nseeks(void *handle)
273{
6eb42155 274 return ((struct seeki *)handle)->tot_seeks;
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275}
276
277double seeki_mean(void *handle)
278{
279 struct seeki *sip = handle;
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280 return sip->total_sectors / sip->tot_seeks;
281}
282
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283long long seeki_median(void *handle)
284{
6eb42155 285 long long rval = 0LL;
5225e788 286 struct seeki *sip = handle;
5225e788 287
6eb42155 288 if (sip->root.rb_node)
8b10aae0 289 (void)__median(sip->root.rb_node, 0LL, sip->tot_seeks / 2,
6eb42155 290 &rval);
5225e788 291
6eb42155 292 return rval;
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293}
294
6eb42155 295int seeki_mode(void *handle, struct mode *mp)
5225e788 296{
5225e788 297 struct seeki *sip = handle;
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298 struct rb_root *root = &sip->root;
299
300 memset(mp, 0, sizeof(struct mode));
8b10aae0 301 if (root->rb_node)
6eb42155 302 __mode(root->rb_node, mp);
5225e788 303
6eb42155 304 return mp->nmds;
5225e788 305}