Daniel Micay
8f0b252c33
mark more out-of-memory conditions as unlikely
2022-01-21 19:03:02 -05:00
Daniel Micay
3cffc1e1af
treat zero size malloc as unlikely
...
Calls to malloc with a zero size are extremely rare relative to normal
usage of the API. It's generally only done by inefficient C code with
open coded dynamic array implementations where they aren't handling zero
size as a special case for their usage of malloc/realloc. Efficient code
wouldn't be making these allocations. It doesn't make sense to optimize
for the performance of rare edge cases caused by inefficient code.
2022-01-21 18:27:04 -05:00
Daniel Micay
b3d78bd5f6
use static const for local constants
2022-01-16 21:02:17 -05:00
Daniel Micay
8d61e63274
add comment about special small size classes
2022-01-16 20:50:49 -05:00
Daniel Micay
81cf2f27a0
calculate slab size class instead of array loop
2022-01-16 16:18:14 -05:00
Daniel Micay
d8cb2d9f7a
use consistent wrappers around clz/ffs
2022-01-16 15:39:59 -05:00
Daniel Micay
86f9c739ee
define constant for u64 bit width
2022-01-16 15:06:36 -05:00
Daniel Micay
536f852538
reuse a single size alignment implementation
2022-01-16 14:44:28 -05:00
Daniel Micay
2a5662948e
rename bitmap manipulation functions
2022-01-04 12:14:55 -05:00
Daniel Micay
d1c39edc9b
use const for malloc_object_size API
2022-01-04 10:14:41 -05:00
Daniel Micay
5f32942263
get rid of canary_value when canaries are disabled
2022-01-03 20:39:30 -05:00
Daniel Micay
3696f071a4
use SLAB_CANARY for conditional checks
2022-01-03 02:17:04 -05:00
Daniel Micay
8ae78237ae
avoid unnecessarily mixing 32-bit and 64-bit ints
...
It's ever so slightly faster to stick to stick to 64-bit arithmetic and
it avoids clang tidy being unhappy about the implicit widening.
2022-01-03 00:54:43 -05:00
Daniel Micay
3f8e9d3184
make MREMAP_MOVE_THRESHOLD into size_t constant
...
This avoids a clang-tidy warning and is a bit cleaner.
2022-01-03 00:32:06 -05:00
jvoisin
9142a9376b
Add a bunch of const qualifiers
2021-12-30 21:25:16 -05:00
jvoisin
0655c1d024
Add a missing const
2021-12-26 18:19:59 -05:00
Daniel Micay
e41d37c3de
remove unnecessary else
2021-09-30 10:57:05 -04:00
Daniel Micay
be6dde66f9
fix missing include for Intel MPK support
2021-05-21 09:07:28 -04:00
Daniel Micay
27fcfccb67
make __GLIBC_PREREQ check for mallinfo2 portable
2021-05-12 22:53:20 -04:00
Daniel Micay
da190f1469
mark pvalloc error path as unlikely
2021-05-12 21:01:13 -04:00
Daniel Micay
b0f81365a8
reuse code for aligned allocation API entry points
2021-05-12 20:59:04 -04:00
Daniel Micay
c9820b6e37
mark alloc_aligned_simple error path unlikely
2021-05-12 20:41:46 -04:00
Daniel Micay
f1cdc1e484
remove disconcerting newline
2021-05-12 20:34:18 -04:00
Daniel Micay
26b74b87bf
improve code reuse for malloc API entry points
2021-05-12 20:28:50 -04:00
Daniel Micay
89faba4232
set errno in malloc_get_state to match glibc
2021-05-12 20:19:12 -04:00
Daniel Micay
a45dacc57b
add support for glibc mallinfo2
2021-05-12 20:07:15 -04:00
Daniel Micay
f9a8e7216b
purge slab memory even if using MAP_FIXED fails
2021-05-12 00:45:19 -04:00
Daniel Micay
5c974bdf82
use region quarantine even if MAP_FIXED call fails
...
This is a more sensible way of handling an out-of-memory failure in this
edge case. It doesn't matter much in practice.
2021-05-12 00:20:03 -04:00
Daniel Micay
2335f56713
add wrapper function for getting slot count
2021-05-10 07:04:50 -04:00
Daniel Micay
13a3aa16d0
improve naming of adjust_size_for_canaries
2021-05-07 04:23:49 -04:00
Daniel Micay
8bfa1a7dd5
use 1 slot for all extended size classes
...
This reduces memory usage and improves security in combination with the
guard slab feature.
2021-05-01 22:10:20 -04:00
Daniel Micay
3952645318
avoid unused variable for some configurations
2021-03-31 12:12:49 -04:00
Daniel Micay
f773a96b59
remove unnecessary sys/mman.h include
2021-03-22 12:25:22 -04:00
Daniel Micay
b84af9b499
add wrapper for madvise
2021-03-22 12:24:26 -04:00
Daniel Micay
e77ffa76d9
add initial malloc_trim slab quarantine purging
...
This currently only purges the quarantines for extended size classes.
2021-03-22 11:16:57 -04:00
Daniel Micay
86b0b3e452
fix !CONFIG_EXTENDED_SIZE_CLASSES configuration
2021-03-21 18:09:02 -04:00
Daniel Micay
a3b4c163eb
drop unused header
2021-03-05 00:35:10 -05:00
Daniel Micay
ddd14bc421
avoid type comparison warning on some platforms
2021-02-16 17:18:35 -05:00
Daniel Micay
29b09648d6
avoid undefined clz and shift in edge cases
...
This is triggered when get_large_size_class is called with a size in the
range [1,4]. This can occur with aligned_alloc(8192, size). In practice,
it doesn't appear to cause any harm, but we shouldn't have any undefined
behavior for well-defined usage of the API. It also occurs if the caller
passes a pointer outside the slab region to free_sized but the expected
size is in the range [1,4]. That usage of free_sized is already going to
be considered undefined, but we should avoid undefined behavior in the
caller from triggering more undefined behavior when it's avoidable.
2021-02-16 08:31:17 -05:00
Thibaut Sautereau
1984cb3b3d
malloc_object_size: avoid fault for invalid region
...
It's the region pointer that can be NULL here, and p was checked at the
beginning of the function.
2021-02-10 17:43:36 -05:00
Thibaut Sautereau
76860c72e1
malloc_usable_size: clean abort on invalid region
...
It's the region pointer that can be NULL here, and p was checked at the
beginning of the function. Also fix the test accordingly.
2021-02-10 17:41:17 -05:00
Daniel Micay
5275563252
fix C++ sized deallocation check false positive
...
This is a compatibility issue triggered when both slab canaries and the
C++ allocator overloads providing sized deallocation checks are enabled.
The boundary where slab allocations are turned into large allocations
due to not having room for the canary in the largest slab allocation
size class triggers a false positive in the sized deallocation check.
2021-01-06 00:18:59 -05:00
Daniel Micay
b90f650153
fix sized deallocation check with large sizes
...
The CONFIG_CXX_ALLOCATOR feature enables sanity checks for sized
deallocation and this wasn't updated to handle the introduction of
performing size class rounding for large sizes.
2020-11-10 13:53:32 -05:00
Daniel Micay
b072022022
perform init sanity checks before MPK unsealing
2020-10-06 17:34:35 -04:00
Daniel Micay
2bb1c39d31
add MPK support for stats retrieval functions
2020-10-06 17:32:25 -04:00
Daniel Micay
0bf18b7c26
optimize malloc_usable_size enforce_init
2020-10-03 15:10:49 -04:00
Daniel Micay
178d4f320f
harden checks for uninitialized usage
2020-10-02 15:06:29 -04:00
Daniel Micay
483b1d7b8b
empty malloc_info output when stats are disabled
2020-09-17 17:42:18 -04:00
Daniel Micay
96eca21ac5
remove thread_local macro workaround glibc < 2.28
2020-09-17 17:38:40 -04:00
Daniel Micay
b4bbd09f07
change label for quarantined large allocations
2020-09-17 16:56:01 -04:00
