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Merge pull request #6197 from LemonBoy/fix-6049

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gpa: Fix bookkeeping logic
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Andrew Kelley 2020-08-31 17:38:17 -04:00 committed by GitHub
commit 0d94cb932f
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1 changed files with 30 additions and 16 deletions
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42
lib/std/heap/general_purpose_allocator.zig
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@ -561,24 +561,25 @@ pub fn GeneralPurposeAllocator(comptime config: Config) type {
return error.OutOfMemory;
}
// Returns true if an allocation of `size` bytes is within the specified
// limits if enable_memory_limit is true
fn isAllocationAllowed(self: *Self, size: usize) bool {
if (config.enable_memory_limit) {
const new_req_bytes = self.total_requested_bytes + size;
if (new_req_bytes > self.requested_memory_limit)
return false;
self.total_requested_bytes = new_req_bytes;
}
return true;
}
fn alloc(allocator: *Allocator, len: usize, ptr_align: u29, len_align: u29, ret_addr: usize) Error![]u8 {
const self = @fieldParentPtr(Self, "allocator", allocator);
const held = self.mutex.acquire();
defer held.release();
const prev_req_bytes = self.total_requested_bytes;
if (config.enable_memory_limit) {
const new_req_bytes = prev_req_bytes + len;
if (new_req_bytes > self.requested_memory_limit) {
return error.OutOfMemory;
}
self.total_requested_bytes = new_req_bytes;
}
errdefer if (config.enable_memory_limit) {
self.total_requested_bytes = prev_req_bytes;
};
const new_aligned_size = math.max(len, ptr_align);
if (new_aligned_size > largest_bucket_object_size) {
try self.large_allocations.ensureCapacity(
@ -588,18 +589,31 @@ pub fn GeneralPurposeAllocator(comptime config: Config) type {
const slice = try self.backing_allocator.allocFn(self.backing_allocator, len, ptr_align, len_align, ret_addr);
// The backing allocator may return a memory block bigger than
// `len`, use the effective size for bookkeeping purposes
if (!self.isAllocationAllowed(slice.len)) {
// Free the block so no memory is leaked
const new_len = try self.backing_allocator.resizeFn(self.backing_allocator, slice, ptr_align, 0, 0, ret_addr);
assert(new_len == 0);
return error.OutOfMemory;
}
const gop = self.large_allocations.getOrPutAssumeCapacity(@ptrToInt(slice.ptr));
assert(!gop.found_existing); // This would mean the kernel double-mapped pages.
gop.entry.value.bytes = slice;
collectStackTrace(ret_addr, &gop.entry.value.stack_addresses);
return slice;
} else {
}
if (!self.isAllocationAllowed(len)) {
return error.OutOfMemory;
}
const new_size_class = math.ceilPowerOfTwoAssert(usize, new_aligned_size);
const ptr = try self.allocSlot(new_size_class, ret_addr);
return ptr[0..len];
}
}
fn createBucket(self: *Self, size_class: usize, bucket_index: usize) Error!*BucketHeader {
const page = try self.backing_allocator.allocAdvanced(u8, page_size, page_size, .exact);