bpo-37537: Compute allocated blocks in _Py_GetAllocatedBlocks() (#14680)

Keeping an account of allocated blocks slows down _PyObject_Malloc()
and _PyObject_Free() by a measureable amount.  Have
_Py_GetAllocatedBlocks() iterate over the arenas to sum up the
allocated blocks for pymalloc.
This commit is contained in:
Neil Schemenauer 2019-07-10 12:04:16 -07:00 committed by GitHub
parent f117d871c4
commit 5d25f2b703
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
2 changed files with 25 additions and 7 deletions

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@ -0,0 +1,3 @@
Compute allocated pymalloc blocks inside _Py_GetAllocatedBlocks(). This
slows down _Py_GetAllocatedBlocks() but gives a small speedup to
_PyObject_Malloc() and _PyObject_Free().

View File

@ -1206,12 +1206,29 @@ static size_t ntimes_arena_allocated = 0;
/* High water mark (max value ever seen) for narenas_currently_allocated. */
static size_t narenas_highwater = 0;
static Py_ssize_t _Py_AllocatedBlocks = 0;
static Py_ssize_t raw_allocated_blocks;
Py_ssize_t
_Py_GetAllocatedBlocks(void)
{
return _Py_AllocatedBlocks;
Py_ssize_t n = raw_allocated_blocks;
/* add up allocated blocks for used pools */
for (uint i = 0; i < maxarenas; ++i) {
/* Skip arenas which are not allocated. */
if (arenas[i].address == NULL) {
continue;
}
uintptr_t base = (uintptr_t)_Py_ALIGN_UP(arenas[i].address, POOL_SIZE);
/* visit every pool in the arena */
assert(base <= (uintptr_t) arenas[i].pool_address);
for (; base < (uintptr_t) arenas[i].pool_address; base += POOL_SIZE) {
poolp p = (poolp)base;
n += p->ref.count;
}
}
return n;
}
@ -1622,13 +1639,12 @@ _PyObject_Malloc(void *ctx, size_t nbytes)
{
void* ptr;
if (pymalloc_alloc(ctx, &ptr, nbytes)) {
_Py_AllocatedBlocks++;
return ptr;
}
ptr = PyMem_RawMalloc(nbytes);
if (ptr != NULL) {
_Py_AllocatedBlocks++;
raw_allocated_blocks++;
}
return ptr;
}
@ -1644,13 +1660,12 @@ _PyObject_Calloc(void *ctx, size_t nelem, size_t elsize)
if (pymalloc_alloc(ctx, &ptr, nbytes)) {
memset(ptr, 0, nbytes);
_Py_AllocatedBlocks++;
return ptr;
}
ptr = PyMem_RawCalloc(nelem, elsize);
if (ptr != NULL) {
_Py_AllocatedBlocks++;
raw_allocated_blocks++;
}
return ptr;
}
@ -1899,10 +1914,10 @@ _PyObject_Free(void *ctx, void *p)
return;
}
_Py_AllocatedBlocks--;
if (!pymalloc_free(ctx, p)) {
/* pymalloc didn't allocate this address */
PyMem_RawFree(p);
raw_allocated_blocks--;
}
}