tjh.dev / kernel
Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel os linux
1
fork

Configure Feed

Select the types of activity you want to include in your feed.

rust: page: optimize rust symbol generation for Page

When build the kernel using the llvm-18.1.3-rust-1.85.0-x86_64
with ARCH=arm64, the following symbols are generated:

$nm vmlinux | grep ' _R'.*Page | rustfilt
ffff8000805b6f98 T <kernel::page::Page>::alloc_page
ffff8000805b715c T <kernel::page::Page>::fill_zero_raw
ffff8000805b720c T <kernel::page::Page>::copy_from_user_slice_raw
ffff8000805b6fb4 T <kernel::page::Page>::read_raw
ffff8000805b7088 T <kernel::page::Page>::write_raw
ffff8000805b72fc T <kernel::page::Page as core::ops::drop::Drop>::drop

These Rust symbols(alloc_page and drop) are trivial wrappers around the C
functions alloc_pages and __free_pages. It doesn't make sense to go
through a trivial wrapper for these functions, so mark them inline.

Link: https://github.com/Rust-for-Linux/linux/issues/1145
Suggested-by: Alice Ryhl <aliceryhl@google.com>
Co-developed-by: Grace Deng <Grace.Deng006@Gmail.com>
Signed-off-by: Grace Deng <Grace.Deng006@Gmail.com>
Signed-off-by: Kunwu Chan <kunwu.chan@hotmail.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20250321080124.484647-1-kunwu.chan@linux.dev
[ Removed spurious colon in title. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

authored by

Kunwu Chan and committed by
Miguel Ojeda 878620c5 82f2b0b9

+2
+2
rust/kernel/page.rs
··· 69 69 /// let page = Page::alloc_page(GFP_KERNEL | __GFP_ZERO)?; 70 70 /// # Ok::<(), kernel::alloc::AllocError>(()) 71 71 /// ``` 72 + #[inline] 72 73 pub fn alloc_page(flags: Flags) -> Result<Self, AllocError> { 73 74 // SAFETY: Depending on the value of `gfp_flags`, this call may sleep. Other than that, it 74 75 // is always safe to call this method. ··· 252 251 } 253 252 254 253 impl Drop for Page { 254 + #[inline] 255 255 fn drop(&mut self) { 256 256 // SAFETY: By the type invariants, we have ownership of the page and can free it. 257 257 unsafe { bindings::__free_pages(self.page.as_ptr(), 0) };