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LibC: Fix malloc bitmap allocator allocation

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Use full pages for bitmap allocators and fix the capacity extension
condition
This commit is contained in:
Bananymous
2026-07-01 12:55:44 +03:00
parent d241975ce1
commit 74e94eedae
1 changed files with 6 additions and 5 deletions
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11
userspace/libraries/LibC/malloc.cpp
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@@ -238,8 +238,6 @@ void* malloc(size_t total_size)
return &header + 1;
}
constexpr size_t allocators_per_page = PAGE_SIZE / sizeof(BitmapAllocator);
void* result = nullptr;
pthread_mutex_lock(&s_allocator_lock);
@@ -248,9 +246,12 @@ void* malloc(size_t total_size)
if ((result = s_allocators[i].allocate(total_size)))
goto malloc_return;
if (s_allocator_capacity % allocators_per_page == 0)
if (s_allocator_count == s_allocator_capacity)
{
void* new_allocators = mmap(nullptr, (s_allocator_capacity + allocators_per_page) * sizeof(BitmapAllocator), PROT_READ | PROT_WRITE, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
const size_t allocator_pages = (s_allocator_capacity * sizeof(BitmapAllocator) + PAGE_SIZE - 1) / PAGE_SIZE;
const size_t new_allocator_pages = allocator_pages + 1;
void* new_allocators = mmap(nullptr, new_allocator_pages * PAGE_SIZE, PROT_READ | PROT_WRITE, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
if (new_allocators == MAP_FAILED)
goto malloc_return;
@@ -260,7 +261,7 @@ void* malloc(size_t total_size)
munmap(s_allocators, s_allocator_capacity * sizeof(BitmapAllocator));
s_allocators = static_cast<BitmapAllocator*>(new_allocators);
s_allocator_capacity = s_allocator_capacity + allocators_per_page;
s_allocator_capacity = new_allocator_pages * PAGE_SIZE / sizeof(BitmapAllocator);
}
if (!s_allocators[s_allocator_count].initialize())