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/* Copyright (c) 1990 Regents of the University of California */ |
1 |
> |
/* Copyright (c) 1992 Regents of the University of California */ |
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#ifndef lint |
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static char SCCSid[] = "$SunId$ LBL"; |
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/* |
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* Fast malloc for memory hogs and VM environments. |
9 |
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* Performs a minimum of searching through free lists. |
10 |
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* bmalloc() doesn't keep track of free lists -- it's basically |
11 |
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* just a buffered call to sbrk(2). However, bmalloc will |
12 |
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* call mscrounge() if sbrk fails. |
13 |
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* bfree() puts memory from any source into malloc free lists. |
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* malloc(), realloc() and free() use buckets |
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* containing blocks in powers of two, similar to CIT routines. |
12 |
< |
* mscrounge() returns whatever memory it can find to satisfy the |
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* bfree() puts memory from any source into malloc free lists. |
13 |
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* bmalloc() doesn't keep track of free lists -- it's usually |
14 |
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* just a buffered call to sbrk(2). However, bmalloc will |
15 |
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* call mscrounge() if sbrk fails. |
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* mscrounge() returns whatever free memory it can find to satisfy the |
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* request along with the number of bytes (modified). |
18 |
+ |
* mcompact() takes the same arguments as mscrounge() (and is in fact |
19 |
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* called by mscrounge() under dire circumstances), but it uses |
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* memory compaction to return a larger block. (MCOMP) |
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* |
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* Greg Ward Lawrence Berkeley Laboratory |
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*/ |
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|
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#include <errno.h> |
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|
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#ifndef BSD |
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#define bcopy(s,d,n) (void)memcpy(d,s,n) |
29 |
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#define bzero(d,n) (void)memset(d,0,n) |
30 |
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extern char *memcpy(), *memset(); |
31 |
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#endif |
32 |
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|
33 |
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#ifdef MSTATS |
34 |
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#include <stdio.h> |
35 |
+ |
static unsigned b_nsbrked = 0; |
36 |
+ |
static unsigned b_nalloced = 0; |
37 |
+ |
static unsigned b_nfreed = 0; |
38 |
+ |
static unsigned b_nscrounged = 0; |
39 |
+ |
static unsigned b_ncompacted = 0; |
40 |
+ |
static unsigned m_nalloced = 0; |
41 |
+ |
static unsigned m_nfreed = 0; |
42 |
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static unsigned m_nwasted = 0; |
43 |
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#else |
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#define NULL 0 |
45 |
+ |
#endif |
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|
47 |
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#ifndef ALIGN |
48 |
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#define ALIGN int /* align type */ |
49 |
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#endif |
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#define BYTES_WORD sizeof(ALIGN) |
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|
52 |
< |
#define MAXINCR (1<<18) /* largest sbrk(2) increment */ |
53 |
< |
|
31 |
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#ifdef NOVMEM |
32 |
< |
#define getpagesize() BYTES_WORD |
52 |
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#ifndef MAXINCR |
53 |
> |
#define MAXINCR (1<<16) /* largest sbrk(2) increment */ |
54 |
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#endif |
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/* malloc free lists */ |
56 |
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typedef union m_head { |
57 |
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union m_head *next; |
58 |
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int bucket; |
58 |
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struct { |
59 |
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short magic; |
60 |
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short bucket; |
61 |
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} a; |
62 |
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ALIGN dummy; |
63 |
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} M_HEAD; |
64 |
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|
65 |
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#define MAGIC 0x1a2 /* magic number for allocated memory */ |
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|
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#define FIRSTBUCKET 3 |
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#define NBUCKETS 30 |
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|
70 |
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static M_HEAD *free_list[NBUCKETS]; |
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|
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static ALIGN dummy_mem; |
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|
74 |
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static char *memlim[2]; |
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|
76 |
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#define DUMMYLOC ((char *)&dummy_mem) |
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|
78 |
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#define BADPTR(p) ((p) < memlim[0] | (p) >= memlim[1]) |
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|
80 |
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#ifdef MCOMP /* memory compaction routines */ |
81 |
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static char seedtab[1024]; /* seed for compaction table */ |
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|
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static struct mblk { |
84 |
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char *ptr; /* pointer to memory block */ |
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unsigned siz; /* size of memory block */ |
86 |
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} cptab = {seedtab, sizeof(seedtab)}; |
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|
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#define mtab(mb) ((struct mblk *)(mb)->ptr) |
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#define mtablen(mb) ((mb)->siz/sizeof(struct mblk)) |
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|
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|
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static int |
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mbcmp(m1, m2) /* compare memory block locations */ |
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register struct mblk *m1, *m2; |
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{ |
96 |
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/* put empty blocks at end */ |
97 |
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if (m1->siz == 0) |
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return(m2->siz == 0 ? 0 : 1); |
99 |
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if (m2->siz == 0) |
100 |
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return(-1); |
101 |
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/* otherwise, ascending order */ |
102 |
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return(m1->ptr - m2->ptr); |
103 |
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} |
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|
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|
106 |
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int |
107 |
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compactfree() /* compact free lists (moving to table) */ |
108 |
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{ |
109 |
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register struct mblk *tp; |
110 |
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register int bucket; |
111 |
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unsigned n, bsiz, ncomp; |
112 |
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/* fill table from free lists */ |
113 |
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tp = mtab(&cptab); n = mtablen(&cptab); |
114 |
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bucket = NBUCKETS-1; bsiz = 1<<(NBUCKETS-1); |
115 |
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ncomp = 0; |
116 |
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for ( ; ; ) { |
117 |
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while (tp->siz) { /* find empty slot */ |
118 |
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if (--n == 0) |
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goto loopexit; |
120 |
+ |
tp++; |
121 |
+ |
} |
122 |
+ |
while (free_list[bucket] == NULL) { /* find block */ |
123 |
+ |
if (--bucket < FIRSTBUCKET) |
124 |
+ |
goto loopexit; |
125 |
+ |
bsiz >>= 1; |
126 |
+ |
} |
127 |
+ |
tp->ptr = (char *)free_list[bucket]; |
128 |
+ |
ncomp += (tp->siz = bsiz + sizeof(M_HEAD)); |
129 |
+ |
free_list[bucket] = free_list[bucket]->next; |
130 |
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} |
131 |
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loopexit: |
132 |
+ |
if (ncomp == 0) |
133 |
+ |
return(0); /* nothing new to compact */ |
134 |
+ |
#ifdef MSTATS |
135 |
+ |
b_ncompacted += ncomp; |
136 |
+ |
#endif |
137 |
+ |
tp = mtab(&cptab); n = mtablen(&cptab); /* sort table */ |
138 |
+ |
qsort((char *)tp, n, sizeof(struct mblk), mbcmp); |
139 |
+ |
ncomp = 0; /* collect blocks */ |
140 |
+ |
while (--n && tp[1].siz) { |
141 |
+ |
if (tp[0].ptr + tp[0].siz == tp[1].ptr) { |
142 |
+ |
tp[1].ptr = tp[0].ptr; |
143 |
+ |
tp[1].siz += tp[0].siz; |
144 |
+ |
ncomp += tp[0].siz; |
145 |
+ |
tp[0].siz = 0; |
146 |
+ |
} |
147 |
+ |
tp++; |
148 |
+ |
} |
149 |
+ |
return(ncomp); |
150 |
+ |
} |
151 |
+ |
|
152 |
+ |
|
153 |
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char * |
154 |
< |
mscrounge(np) /* search free lists trying to satisfy request */ |
154 |
> |
mcompact(np) /* compact free lists to satisfy request */ |
155 |
> |
unsigned *np; |
156 |
> |
{ |
157 |
> |
struct mblk *tab; |
158 |
> |
unsigned tablen; |
159 |
> |
register struct mblk *bp, *big; |
160 |
> |
|
161 |
> |
for ( ; ; ) { |
162 |
> |
/* compact free lists */ |
163 |
> |
while (compactfree()) |
164 |
> |
; |
165 |
> |
/* find largest block */ |
166 |
> |
tab = mtab(&cptab); tablen = mtablen(&cptab); |
167 |
> |
big = tab; |
168 |
> |
bp = tab + tablen; |
169 |
> |
while (--bp > tab) |
170 |
> |
if (bp->siz > big->siz) |
171 |
> |
big = bp; |
172 |
> |
if (big->siz >= *np) { /* big enough? */ |
173 |
> |
*np = big->siz; |
174 |
> |
big->siz = 0; /* remove from table */ |
175 |
> |
return(big->ptr); /* return it */ |
176 |
> |
} |
177 |
> |
if (mtablen(big) <= tablen) { |
178 |
> |
*np = 0; /* cannot grow table */ |
179 |
> |
return(NULL); /* report failure */ |
180 |
> |
} |
181 |
> |
/* enlarge table, free old one */ |
182 |
> |
mtab(big)[0].ptr = cptab.ptr; |
183 |
> |
mtab(big)[0].siz = cptab.siz; |
184 |
> |
cptab.ptr = big->ptr; |
185 |
> |
cptab.siz = big->siz; |
186 |
> |
big->siz = 0; /* clear and copy */ |
187 |
> |
bcopy((char *)tab, (char *)(mtab(&cptab)+1), |
188 |
> |
tablen*sizeof(struct mblk)); |
189 |
> |
bzero((char *)(mtab(&cptab)+tablen+1), |
190 |
> |
(mtablen(&cptab)-tablen-1)*sizeof(struct mblk)); |
191 |
> |
} /* next round */ |
192 |
> |
} |
193 |
> |
#endif /* MCOMP */ |
194 |
> |
|
195 |
> |
|
196 |
> |
char * |
197 |
> |
mscrounge(np) /* search free lists to satisfy request */ |
198 |
|
register unsigned *np; |
199 |
|
{ |
200 |
|
char *p; |
207 |
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*np = bsiz+sizeof(M_HEAD); |
208 |
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p = (char *)free_list[bucket]; |
209 |
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free_list[bucket] = free_list[bucket]->next; |
210 |
+ |
#ifdef MSTATS |
211 |
+ |
b_nscrounged += *np; |
212 |
+ |
#endif |
213 |
|
return(p); |
214 |
|
} |
215 |
+ |
#ifdef MCOMP |
216 |
+ |
return(mcompact(np)); /* try compaction */ |
217 |
+ |
#else |
218 |
|
*np = 0; |
219 |
|
return(NULL); |
220 |
+ |
#endif |
221 |
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} |
222 |
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|
223 |
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|
237 |
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pagesz = amnt = getpagesize(); |
238 |
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nrem = (int)sbrk(0); /* page align break */ |
239 |
|
nrem = pagesz - (nrem&(pagesz-1)); |
240 |
< |
bpos = sbrk(nrem); /* word aligned! */ |
240 |
> |
bpos = sbrk(nrem); |
241 |
|
if ((int)bpos == -1) |
242 |
|
return(NULL); |
243 |
+ |
#ifdef MSTATS |
244 |
+ |
b_nsbrked += nrem; |
245 |
+ |
#endif |
246 |
+ |
bpos += nrem & (BYTES_WORD-1); /* align pointer */ |
247 |
+ |
nrem &= ~(BYTES_WORD-1); |
248 |
+ |
memlim[0] = bpos; |
249 |
+ |
memlim[1] = bpos + nrem; |
250 |
|
} |
251 |
|
|
252 |
|
n = (n+(BYTES_WORD-1))&~(BYTES_WORD-1); /* word align rqst. */ |
253 |
|
|
254 |
|
if (n > nrem) { /* need more core */ |
255 |
+ |
tryagain: |
256 |
|
if (n > amnt) { /* big chunk */ |
257 |
|
thisamnt = (n+(pagesz-1))&~(pagesz-1); |
258 |
|
if (thisamnt <= MAXINCR) /* increase amnt */ |
260 |
|
} else |
261 |
|
thisamnt = amnt; |
262 |
|
p = sbrk(thisamnt); |
263 |
< |
if ((int)p == -1) { /* uh-oh */ |
264 |
< |
thisamnt = n; /* search free lists */ |
265 |
< |
p = mscrounge(&thisamnt); |
266 |
< |
if (p == NULL) /* we're really out */ |
263 |
> |
if ((int)p == -1) { /* uh-oh, ENOMEM */ |
264 |
> |
errno = 0; /* call cavalry */ |
265 |
> |
if (thisamnt >= n+pagesz) { |
266 |
> |
amnt = pagesz; /* minimize request */ |
267 |
> |
goto tryagain; |
268 |
> |
} |
269 |
> |
thisamnt = n; |
270 |
> |
p = mscrounge(&thisamnt); /* search free lists */ |
271 |
> |
if (p == NULL) { /* we're really out */ |
272 |
> |
errno = ENOMEM; |
273 |
|
return(NULL); |
274 |
+ |
} |
275 |
|
} |
276 |
+ |
#ifdef MSTATS |
277 |
+ |
else b_nsbrked += thisamnt; |
278 |
+ |
#endif |
279 |
|
if (p != bpos+nrem) { /* not an increment */ |
280 |
< |
bfree(bpos, nrem); |
280 |
> |
bfree(bpos, nrem); /* free what we have */ |
281 |
|
bpos = p; |
282 |
|
nrem = thisamnt; |
283 |
< |
} else |
283 |
> |
} else /* otherwise tack on */ |
284 |
|
nrem += thisamnt; |
285 |
+ |
if (bpos < memlim[0]) |
286 |
+ |
memlim[0] = bpos; |
287 |
+ |
if (bpos + nrem > memlim[1]) |
288 |
+ |
memlim[1] = bpos + nrem; |
289 |
|
} |
290 |
|
p = bpos; |
291 |
|
bpos += n; /* advance */ |
292 |
|
nrem -= n; |
293 |
+ |
#ifdef MSTATS |
294 |
+ |
b_nalloced += n; |
295 |
+ |
#endif |
296 |
|
return(p); |
297 |
|
} |
298 |
|
|
303 |
|
{ |
304 |
|
register int bucket; |
305 |
|
register unsigned bsiz; |
306 |
< |
/* find largest bucket */ |
307 |
< |
bucket = 0; |
308 |
< |
for (bsiz = 1; bsiz+sizeof(M_HEAD) <= n; bsiz <<= 1) |
309 |
< |
bucket++; |
310 |
< |
while (bucket > FIRSTBUCKET) { |
311 |
< |
bsiz >>= 1; |
312 |
< |
bucket--; |
313 |
< |
if (n < bsiz+sizeof(M_HEAD)) /* nothing for this bucket */ |
314 |
< |
continue; |
315 |
< |
((M_HEAD *)p)->next = free_list[bucket]; |
316 |
< |
free_list[bucket] = (M_HEAD *)p; |
136 |
< |
p += bsiz+sizeof(M_HEAD); |
137 |
< |
n -= bsiz+sizeof(M_HEAD); |
306 |
> |
|
307 |
> |
if (n < 1<<FIRSTBUCKET) |
308 |
> |
return; |
309 |
> |
#ifdef MSTATS |
310 |
> |
b_nfreed += n; |
311 |
> |
#endif |
312 |
> |
/* align pointer */ |
313 |
> |
bsiz = BYTES_WORD - ((unsigned)p&(BYTES_WORD-1)); |
314 |
> |
if (bsiz < BYTES_WORD) { |
315 |
> |
p += bsiz; |
316 |
> |
n -= bsiz; |
317 |
|
} |
318 |
+ |
if (p < memlim[0]) |
319 |
+ |
memlim[0] = p; |
320 |
+ |
if (p + n > memlim[1]) |
321 |
+ |
memlim[1] = p + n; |
322 |
+ |
/* fill big buckets first */ |
323 |
+ |
for (bucket = NBUCKETS-1, bsiz = 1<<(NBUCKETS-1); |
324 |
+ |
bucket >= FIRSTBUCKET; bucket--, bsiz >>= 1) |
325 |
+ |
if (n >= bsiz+sizeof(M_HEAD)) { |
326 |
+ |
((M_HEAD *)p)->next = free_list[bucket]; |
327 |
+ |
free_list[bucket] = (M_HEAD *)p; |
328 |
+ |
p += bsiz+sizeof(M_HEAD); |
329 |
+ |
n -= bsiz+sizeof(M_HEAD); |
330 |
+ |
} |
331 |
|
} |
332 |
|
|
333 |
|
|
338 |
|
register M_HEAD *mp; |
339 |
|
register int bucket; |
340 |
|
register unsigned bsiz; |
341 |
< |
|
341 |
> |
/* don't return NULL on 0 request */ |
342 |
|
if (n == 0) |
343 |
< |
return(NULL); |
343 |
> |
return(DUMMYLOC); |
344 |
|
/* find first bucket that fits */ |
345 |
< |
bucket = FIRSTBUCKET; |
346 |
< |
for (bsiz = 1<<FIRSTBUCKET; bsiz < n; bsiz <<= 1) |
347 |
< |
bucket++; |
348 |
< |
if (free_list[bucket] == NULL) { |
345 |
> |
for (bucket = FIRSTBUCKET, bsiz = 1<<FIRSTBUCKET; |
346 |
> |
bucket < NBUCKETS; bucket++, bsiz <<= 1) |
347 |
> |
if (bsiz >= n) |
348 |
> |
break; |
349 |
> |
if (bucket >= NBUCKETS) { |
350 |
> |
errno = EINVAL; |
351 |
> |
return(NULL); |
352 |
> |
} |
353 |
> |
if (free_list[bucket] == NULL) { /* need more core */ |
354 |
|
mp = (M_HEAD *)bmalloc(bsiz+sizeof(M_HEAD)); |
355 |
|
if (mp == NULL) |
356 |
|
return(NULL); |
357 |
< |
} else { |
357 |
> |
} else { /* got it */ |
358 |
|
mp = free_list[bucket]; |
359 |
|
free_list[bucket] = mp->next; |
360 |
|
} |
361 |
< |
mp->bucket = bucket; |
361 |
> |
#ifdef MSTATS |
362 |
> |
m_nalloced += bsiz + sizeof(M_HEAD); |
363 |
> |
m_nwasted += bsiz + sizeof(M_HEAD) - n; |
364 |
> |
#endif |
365 |
> |
mp->a.magic = MAGIC; /* tag block */ |
366 |
> |
mp->a.bucket = bucket; |
367 |
|
return((char *)(mp+1)); |
368 |
|
} |
369 |
|
|
370 |
|
|
371 |
|
char * |
372 |
|
realloc(op, n) /* reallocate memory using malloc() */ |
373 |
< |
char *op; |
373 |
> |
register char *op; |
374 |
|
unsigned n; |
375 |
|
{ |
376 |
< |
register char *p; |
376 |
> |
char *p; |
377 |
|
register unsigned on; |
378 |
< |
|
379 |
< |
if (op != NULL) |
380 |
< |
on = 1 << ((M_HEAD *)op-1)->bucket; |
378 |
> |
/* get old size */ |
379 |
> |
if (op != DUMMYLOC && !BADPTR(op) && |
380 |
> |
((M_HEAD *)op-1)->a.magic == MAGIC) |
381 |
> |
on = 1 << ((M_HEAD *)op-1)->a.bucket; |
382 |
|
else |
383 |
|
on = 0; |
384 |
< |
if (n <= on && n > on>>1) |
384 |
> |
if (n <= on && (n > on>>1 || on == 1<<FIRSTBUCKET)) |
385 |
|
return(op); /* same bucket */ |
386 |
< |
p = malloc(n); |
387 |
< |
if (p != NULL) |
388 |
< |
#ifdef BSD |
386 |
> |
if ((p = malloc(n)) == NULL) |
387 |
> |
return(n<=on ? op : NULL); |
388 |
> |
if (on) { |
389 |
|
bcopy(op, p, n>on ? on : n); |
390 |
< |
#else |
391 |
< |
(void)memcpy(p, op, n>on ? on : n); |
189 |
< |
#endif |
190 |
< |
free(op); |
390 |
> |
free(op); |
391 |
> |
} |
392 |
|
return(p); |
393 |
|
} |
394 |
|
|
399 |
|
register M_HEAD *mp; |
400 |
|
register int bucket; |
401 |
|
|
402 |
< |
if (p == NULL) |
403 |
< |
return; |
402 |
> |
if (p == DUMMYLOC) |
403 |
> |
return(1); |
404 |
> |
if (BADPTR(p)) |
405 |
> |
goto invalid; |
406 |
|
mp = (M_HEAD *)p - 1; |
407 |
< |
bucket = mp->bucket; |
407 |
> |
if (mp->a.magic != MAGIC) /* sanity check */ |
408 |
> |
goto invalid; |
409 |
> |
bucket = mp->a.bucket; |
410 |
> |
if (bucket < FIRSTBUCKET | bucket >= NBUCKETS) |
411 |
> |
goto invalid; |
412 |
|
mp->next = free_list[bucket]; |
413 |
|
free_list[bucket] = mp; |
414 |
+ |
#ifdef MSTATS |
415 |
+ |
m_nfreed += (1 << bucket) + sizeof(M_HEAD); |
416 |
+ |
#endif |
417 |
+ |
return(1); |
418 |
+ |
invalid: |
419 |
+ |
errno = EINVAL; |
420 |
+ |
return(0); |
421 |
|
} |
422 |
|
|
423 |
|
|
424 |
< |
#ifndef NOVMEM |
425 |
< |
#ifndef BSD |
426 |
< |
#include <sys/var.h> |
213 |
< |
int |
214 |
< |
getpagesize() /* use SYSV var structure to get page size */ |
424 |
> |
#ifdef MSTATS |
425 |
> |
printmemstats(fp) /* print memory statistics to stream */ |
426 |
> |
FILE *fp; |
427 |
|
{ |
428 |
< |
static int pagesz = 0; |
429 |
< |
struct var v; |
428 |
> |
register int i; |
429 |
> |
int n; |
430 |
> |
register M_HEAD *mp; |
431 |
> |
unsigned int total = 0; |
432 |
|
|
433 |
< |
if (pagesz == 0) { |
434 |
< |
uvar(&v); |
435 |
< |
pagesz = 1 << v.v_pageshift; |
433 |
> |
fprintf(fp, "Memory statistics:\n"); |
434 |
> |
fprintf(fp, "\tbmalloc: %d bytes from sbrk\n", b_nsbrked); |
435 |
> |
fprintf(fp, "\tbmalloc: %d bytes allocated\n", b_nalloced); |
436 |
> |
fprintf(fp, "\tbmalloc: %d bytes freed\n", b_nfreed); |
437 |
> |
fprintf(fp, "\tbmalloc: %d bytes scrounged\n", b_nscrounged); |
438 |
> |
fprintf(fp, "\tbmalloc: %d bytes compacted\n", b_ncompacted); |
439 |
> |
fprintf(fp, "\tmalloc: %d bytes allocated\n", m_nalloced); |
440 |
> |
fprintf(fp, "\tmalloc: %d bytes wasted (%.1f%%)\n", m_nwasted, |
441 |
> |
100.0*m_nwasted/m_nalloced); |
442 |
> |
fprintf(fp, "\tmalloc: %d bytes freed\n", m_nfreed); |
443 |
> |
for (i = NBUCKETS-1; i >= FIRSTBUCKET; i--) { |
444 |
> |
n = 0; |
445 |
> |
for (mp = free_list[i]; mp != NULL; mp = mp->next) |
446 |
> |
n++; |
447 |
> |
if (n) { |
448 |
> |
fprintf(fp, "\t%d * %u\n", n, 1<<i); |
449 |
> |
total += n * ((1<<i) + sizeof(M_HEAD)); |
450 |
> |
} |
451 |
|
} |
452 |
< |
return(pagesz); |
452 |
> |
fprintf(fp, "\t %u total bytes in free list\n", total); |
453 |
|
} |
225 |
– |
#endif |
454 |
|
#endif |