cosmopolitan/third_party/dlmalloc/dlmalloc_stats.c

48 lines
1.7 KiB
C

#include "third_party/dlmalloc/dlmalloc.h"
#include "libc/mem/mem.h"
#include "libc/str/str.h"
/**
* Prints on stderr the amount of space obtained from the system (both
* via sbrk and mmap), the maximum amount (which may be more than
* current if malloc_trim and/or munmap got called), and the current
* number of bytes allocated via malloc (or realloc, etc) but not yet
* freed. Note that this is the number of bytes allocated, not the
* number requested. It will be larger than the number requested because
* of alignment and bookkeeping overhead. Because it includes alignment
* wastage as being in use, this figure may be greater than zero even
* when no user-level chunks are allocated.
*
* The reported current and maximum system memory can be inaccurate if a
* program makes other calls to system memory allocation functions
* (normally sbrk) outside of malloc.
*
* malloc_stats prints only the most commonly interesting statistics.
* More information can be obtained by calling mallinfo.
*/
struct MallocStats dlmalloc_stats(mstate m) {
struct MallocStats res;
memset(&res, 0, sizeof(res));
ensure_initialization();
if (!PREACTION(m)) {
check_malloc_state(m);
if (is_initialized(m)) {
msegmentptr s = &m->seg;
res.maxfp = m->max_footprint;
res.fp = m->footprint;
res.used = res.fp - (m->topsize + TOP_FOOT_SIZE);
while (s != 0) {
mchunkptr q = align_as_chunk(s->base);
while (segment_holds(s, q) && q != m->top &&
q->head != FENCEPOST_HEAD) {
if (!is_inuse(q)) res.used -= chunksize(q);
q = next_chunk(q);
}
s = s->next;
}
}
POSTACTION(m); /* drop lock */
}
return res;
}