[−][src]Crate alloc_counter
Alloc counters
A redesign of the Quick and Dirty Allocation Profiling Tool.
Features
-
Count allocations, reallocations and deallocations individually with
count_alloc
. -
Allow, deny, and forbid use of the global allocator with
allow_alloc
,deny_alloc
andforbid_alloc
. -
#[no_alloc]
function attribute to deny and#[no_alloc(forbid)]
to forbid use of the global allocator.
Limitations and known issues
- Methods must either take a reference to
self
orSelf
must be aCopy
type.
Usage
An AllocCounter<A>
wraps an allocator A
to individually count the number of calls to
alloc
, realloc
, and dealloc
.
use alloc_counter::AllocCounter; #[global_allocator] static A: AllocCounter<MyAllocator> = AllocCounter(MyAllocator);
Std-users may prefer to inherit their system's allocator.
use alloc_counter::AllocCounterSystem; #[global_allocator] static A: AllocCounterSystem = AllocCounterSystem;
To count the allocations of an expression, use count_alloc
.
assert_eq!( count_alloc(|| { // no alloc let mut v = Vec::new(); // alloc v.push(0); // realloc v.push(1); // dealloc }) .0, (1, 1, 1) );
To deny allocations for an expression use deny_alloc
.
fn foo(b: Box<i32>) { // dropping causes a panic deny_alloc(|| drop(b)) } foo(Box::new(0));
Similar to Rust's lints, you can still allow allocation inside a deny block.
fn foo(b: Box<i32>) { deny_alloc(|| allow_alloc(|| drop(b))) } foo(Box::new(0));
Forbidding allocations forces a panic even when allow_alloc
is used.
fn foo(b: Box<i32>) { // panics because of outer `forbid`, even though drop happens in an allow block forbid_alloc(|| allow_alloc(|| drop(b))) } foo(Box::new(0));
For added sugar you may use the #[no_alloc]
attribute on functions, including methods with
self-binds. #[no_alloc]
expands to calling deny_alloc
and forcefully moves the parameters
into the checked block. #[no_alloc(forbid)]
calls forbid_alloc
.
#[no_alloc(forbid)] fn foo(b: Box<i32>) { allow_alloc(|| drop(b)) } foo(Box::new(0));
Re-exports
pub use alloc_counter_macro::no_alloc; |
Structs
AllocCounter | An allocator that tracks allocations, reallocations, and deallocations in live code. It uses another backing allocator for actual heap management. |
Constants
AllocCounterSystem | An allocator that counts allocations, reallocations, and deallocations in live code. It uses the operating system as a backing implementation for actual heap management. |
Functions
allow_alloc | Allow allocations for a closure, even if running in a deny closure. Allocations during a forbid closure will still cause a panic. |
count_alloc | Count the allocations, reallocations, and deallocations that happen during execution of a closure. |
deny_alloc | Panic on any allocations during the provided closure. If code within the closure
calls |
forbid_alloc | Panic on any allocations during the provided closure, even if the closure contains
code in an |
Type Definitions
AllocCounterSystem | Type alias for an |