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| author | Andreas Kling <kling@serenityos.org> | 2021-03-04 10:05:38 +0100 |
|---|---|---|
| committer | Andreas Kling <kling@serenityos.org> | 2021-03-04 10:11:37 +0100 |
| commit | 4515652001b715a0da7908d815ceb5c00e8c79b9 (patch) | |
| tree | 845535a7369a0d21067b80632064ac2fd77ca12b /Kernel/VM/AnonymousVMObject.cpp | |
| parent | ddaeb294dc8d76f3636cd1dcab88a67d6b3e0610 (diff) | |
| download | serenity-4515652001b715a0da7908d815ceb5c00e8c79b9.zip | |
Kernel: Remove 1 level of indirection for AnonymousVMObject CoW bitmaps
Instead of keeping AnonymousVMObject::m_cow_map in an OwnPtr<Bitmap>,
just make the Bitmap a regular value member. This increases the size
of the VMObject by 8 bytes, but removes some of the kmalloc/kfree spam
incurred by sys$fork().
Diffstat (limited to 'Kernel/VM/AnonymousVMObject.cpp')
| -rw-r--r-- | Kernel/VM/AnonymousVMObject.cpp | 22 |
1 files changed, 11 insertions, 11 deletions
diff --git a/Kernel/VM/AnonymousVMObject.cpp b/Kernel/VM/AnonymousVMObject.cpp index 7a8f1f3513..06a3581378 100644 --- a/Kernel/VM/AnonymousVMObject.cpp +++ b/Kernel/VM/AnonymousVMObject.cpp @@ -336,7 +336,7 @@ size_t AnonymousVMObject::count_needed_commit_pages_for_nonvolatile_range(const auto range_end = range.base + range.count; for (size_t page_index = range.base; page_index < range_end; page_index++) { // COW pages are accounted for in m_shared_committed_cow_pages - if (m_cow_map && m_cow_map->get(page_index)) + if (!m_cow_map.is_null() && m_cow_map.get(page_index)) continue; auto& phys_page = m_physical_pages[page_index]; if (phys_page && phys_page->is_shared_zero_page()) @@ -355,7 +355,7 @@ size_t AnonymousVMObject::mark_committed_pages_for_nonvolatile_range(const Volat auto range_end = range.base + range.count; for (size_t page_index = range.base; page_index < range_end; page_index++) { // COW pages are accounted for in m_shared_committed_cow_pages - if (m_cow_map && m_cow_map->get(page_index)) + if (!m_cow_map.is_null() && m_cow_map.get(page_index)) continue; auto& phys_page = m_physical_pages[page_index]; if (phys_page && phys_page->is_shared_zero_page()) { @@ -395,17 +395,17 @@ RefPtr<PhysicalPage> AnonymousVMObject::allocate_committed_page(size_t page_inde Bitmap& AnonymousVMObject::ensure_cow_map() { - if (!m_cow_map) - m_cow_map = make<Bitmap>(page_count(), true); - return *m_cow_map; + if (m_cow_map.is_null()) + m_cow_map = Bitmap { page_count(), true }; + return m_cow_map; } void AnonymousVMObject::ensure_or_reset_cow_map() { - if (!m_cow_map) - m_cow_map = make<Bitmap>(page_count(), true); + if (m_cow_map.is_null()) + ensure_cow_map(); else - m_cow_map->fill(true); + m_cow_map.fill(true); } bool AnonymousVMObject::should_cow(size_t page_index, bool is_shared) const @@ -415,7 +415,7 @@ bool AnonymousVMObject::should_cow(size_t page_index, bool is_shared) const return true; if (is_shared) return false; - return m_cow_map && m_cow_map->get(page_index); + return !m_cow_map.is_null() && m_cow_map.get(page_index); } void AnonymousVMObject::set_should_cow(size_t page_index, bool cow) @@ -425,9 +425,9 @@ void AnonymousVMObject::set_should_cow(size_t page_index, bool cow) size_t AnonymousVMObject::cow_pages() const { - if (!m_cow_map) + if (m_cow_map.is_null()) return 0; - return m_cow_map->count_slow(true); + return m_cow_map.count_slow(true); } bool AnonymousVMObject::is_nonvolatile(size_t page_index) |