diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2023-10-30 20:30:49 -1000 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2023-10-30 20:30:49 -1000 |
commit | 455cdcb45f8fa9e7c70273e7bec0537ff02d5247 (patch) | |
tree | c0e07c22f2c4e65448f999ef277e4bcd6788fcf3 /rust | |
parent | 2b93c2c3c02f4243d4c773b880fc86e2788f013d (diff) | |
parent | 3857af38e57a80b15b994e19d1f4301cac796481 (diff) | |
download | lwn-455cdcb45f8fa9e7c70273e7bec0537ff02d5247.tar.gz lwn-455cdcb45f8fa9e7c70273e7bec0537ff02d5247.zip |
Merge tag 'rust-6.7' of https://github.com/Rust-for-Linux/linux
Pull rust updates from Miguel Ojeda:
"A small one compared to the previous one in terms of features. In
terms of lines, as usual, the 'alloc' version upgrade accounts for
most of them.
Toolchain and infrastructure:
- Upgrade to Rust 1.73.0
This time around, due to how the kernel and Rust schedules have
aligned, there are two upgrades in fact. They contain the fixes for
a few issues we reported to the Rust project.
In addition, a few cleanups indicated by the upgraded compiler or
possible thanks to it. For instance, the compiler now detects
redundant explicit links.
- A couple changes to the Rust 'Makefile' so that it can be used with
toybox tools, allowing Rust to be used in the Android kernel build.
x86:
- Enable IBT if enabled in C
Documentation:
- Add "The Rust experiment" section to the Rust index page
MAINTAINERS:
- Add Maintainer Entry Profile field ('P:').
- Update our 'W:' field to point to the webpage we have been building
this year"
* tag 'rust-6.7' of https://github.com/Rust-for-Linux/linux:
docs: rust: add "The Rust experiment" section
x86: Enable IBT in Rust if enabled in C
rust: Use grep -Ev rather than relying on GNU grep
rust: Use awk instead of recent xargs
rust: upgrade to Rust 1.73.0
rust: print: use explicit link in documentation
rust: task: remove redundant explicit link
rust: kernel: remove `#[allow(clippy::new_ret_no_self)]`
MAINTAINERS: add Maintainer Entry Profile field for Rust
MAINTAINERS: update Rust webpage
rust: upgrade to Rust 1.72.1
rust: arc: add explicit `drop()` around `Box::from_raw()`
Diffstat (limited to 'rust')
-rw-r--r-- | rust/Makefile | 8 | ||||
-rw-r--r-- | rust/alloc/alloc.rs | 21 | ||||
-rw-r--r-- | rust/alloc/boxed.rs | 56 | ||||
-rw-r--r-- | rust/alloc/lib.rs | 13 | ||||
-rw-r--r-- | rust/alloc/raw_vec.rs | 30 | ||||
-rw-r--r-- | rust/alloc/vec/drain_filter.rs | 199 | ||||
-rw-r--r-- | rust/alloc/vec/extract_if.rs | 115 | ||||
-rw-r--r-- | rust/alloc/vec/mod.rs | 110 | ||||
-rw-r--r-- | rust/alloc/vec/spec_extend.rs | 8 | ||||
-rw-r--r-- | rust/compiler_builtins.rs | 1 | ||||
-rw-r--r-- | rust/kernel/init.rs | 20 | ||||
-rw-r--r-- | rust/kernel/print.rs | 1 | ||||
-rw-r--r-- | rust/kernel/sync/arc.rs | 2 | ||||
-rw-r--r-- | rust/kernel/sync/condvar.rs | 1 | ||||
-rw-r--r-- | rust/kernel/sync/lock.rs | 1 | ||||
-rw-r--r-- | rust/kernel/task.rs | 2 |
16 files changed, 255 insertions, 333 deletions
diff --git a/rust/Makefile b/rust/Makefile index 7dbf9abe0d01..28dd31cf1179 100644 --- a/rust/Makefile +++ b/rust/Makefile @@ -336,13 +336,13 @@ quiet_cmd_bindgen = BINDGEN $@ $(bindgen_target_cflags) $(bindgen_target_extra) $(obj)/bindings/bindings_generated.rs: private bindgen_target_flags = \ - $(shell grep -v '^#\|^$$' $(srctree)/$(src)/bindgen_parameters) + $(shell grep -Ev '^#|^$$' $(srctree)/$(src)/bindgen_parameters) $(obj)/bindings/bindings_generated.rs: $(src)/bindings/bindings_helper.h \ $(src)/bindgen_parameters FORCE $(call if_changed_dep,bindgen) $(obj)/uapi/uapi_generated.rs: private bindgen_target_flags = \ - $(shell grep -v '^#\|^$$' $(srctree)/$(src)/bindgen_parameters) + $(shell grep -Ev '^#|^$$' $(srctree)/$(src)/bindgen_parameters) $(obj)/uapi/uapi_generated.rs: $(src)/uapi/uapi_helper.h \ $(src)/bindgen_parameters FORCE $(call if_changed_dep,bindgen) @@ -364,9 +364,7 @@ $(obj)/bindings/bindings_helpers_generated.rs: $(src)/helpers.c FORCE quiet_cmd_exports = EXPORTS $@ cmd_exports = \ $(NM) -p --defined-only $< \ - | grep -E ' (T|R|D) ' | cut -d ' ' -f 3 \ - | xargs -Isymbol \ - echo 'EXPORT_SYMBOL_RUST_GPL(symbol);' > $@ + | awk '/ (T|R|D) / {printf "EXPORT_SYMBOL_RUST_GPL(%s);\n",$$3}' > $@ $(obj)/exports_core_generated.h: $(obj)/core.o FORCE $(call if_changed,exports) diff --git a/rust/alloc/alloc.rs b/rust/alloc/alloc.rs index 0b6bf5b6da43..8cb4a31cf6e5 100644 --- a/rust/alloc/alloc.rs +++ b/rust/alloc/alloc.rs @@ -6,9 +6,7 @@ #[cfg(not(test))] use core::intrinsics; -use core::intrinsics::{min_align_of_val, size_of_val}; -use core::ptr::Unique; #[cfg(not(test))] use core::ptr::{self, NonNull}; @@ -40,7 +38,6 @@ extern "Rust" { #[rustc_nounwind] fn __rust_alloc_zeroed(size: usize, align: usize) -> *mut u8; - #[cfg(not(bootstrap))] static __rust_no_alloc_shim_is_unstable: u8; } @@ -98,7 +95,6 @@ pub unsafe fn alloc(layout: Layout) -> *mut u8 { unsafe { // Make sure we don't accidentally allow omitting the allocator shim in // stable code until it is actually stabilized. - #[cfg(not(bootstrap))] core::ptr::read_volatile(&__rust_no_alloc_shim_is_unstable); __rust_alloc(layout.size(), layout.align()) @@ -339,22 +335,6 @@ unsafe fn exchange_malloc(size: usize, align: usize) -> *mut u8 { } } -#[cfg_attr(not(test), lang = "box_free")] -#[inline] -// This signature has to be the same as `Box`, otherwise an ICE will happen. -// When an additional parameter to `Box` is added (like `A: Allocator`), this has to be added here as -// well. -// For example if `Box` is changed to `struct Box<T: ?Sized, A: Allocator>(Unique<T>, A)`, -// this function has to be changed to `fn box_free<T: ?Sized, A: Allocator>(Unique<T>, A)` as well. -pub(crate) unsafe fn box_free<T: ?Sized, A: Allocator>(ptr: Unique<T>, alloc: A) { - unsafe { - let size = size_of_val(ptr.as_ref()); - let align = min_align_of_val(ptr.as_ref()); - let layout = Layout::from_size_align_unchecked(size, align); - alloc.deallocate(From::from(ptr.cast()), layout) - } -} - // # Allocation error handler #[cfg(not(no_global_oom_handling))] @@ -414,7 +394,6 @@ pub mod __alloc_error_handler { static __rust_alloc_error_handler_should_panic: u8; } - #[allow(unused_unsafe)] if unsafe { __rust_alloc_error_handler_should_panic != 0 } { panic!("memory allocation of {size} bytes failed") } else { diff --git a/rust/alloc/boxed.rs b/rust/alloc/boxed.rs index c8173cea8317..9620eba17268 100644 --- a/rust/alloc/boxed.rs +++ b/rust/alloc/boxed.rs @@ -159,12 +159,12 @@ use core::hash::{Hash, Hasher}; use core::iter::FusedIterator; use core::marker::Tuple; use core::marker::Unsize; -use core::mem; +use core::mem::{self, SizedTypeProperties}; use core::ops::{ CoerceUnsized, Deref, DerefMut, DispatchFromDyn, Generator, GeneratorState, Receiver, }; use core::pin::Pin; -use core::ptr::{self, Unique}; +use core::ptr::{self, NonNull, Unique}; use core::task::{Context, Poll}; #[cfg(not(no_global_oom_handling))] @@ -483,8 +483,12 @@ impl<T, A: Allocator> Box<T, A> { where A: Allocator, { - let layout = Layout::new::<mem::MaybeUninit<T>>(); - let ptr = alloc.allocate(layout)?.cast(); + let ptr = if T::IS_ZST { + NonNull::dangling() + } else { + let layout = Layout::new::<mem::MaybeUninit<T>>(); + alloc.allocate(layout)?.cast() + }; unsafe { Ok(Box::from_raw_in(ptr.as_ptr(), alloc)) } } @@ -553,8 +557,12 @@ impl<T, A: Allocator> Box<T, A> { where A: Allocator, { - let layout = Layout::new::<mem::MaybeUninit<T>>(); - let ptr = alloc.allocate_zeroed(layout)?.cast(); + let ptr = if T::IS_ZST { + NonNull::dangling() + } else { + let layout = Layout::new::<mem::MaybeUninit<T>>(); + alloc.allocate_zeroed(layout)?.cast() + }; unsafe { Ok(Box::from_raw_in(ptr.as_ptr(), alloc)) } } @@ -679,14 +687,16 @@ impl<T> Box<[T]> { #[unstable(feature = "allocator_api", issue = "32838")] #[inline] pub fn try_new_uninit_slice(len: usize) -> Result<Box<[mem::MaybeUninit<T>]>, AllocError> { - unsafe { + let ptr = if T::IS_ZST || len == 0 { + NonNull::dangling() + } else { let layout = match Layout::array::<mem::MaybeUninit<T>>(len) { Ok(l) => l, Err(_) => return Err(AllocError), }; - let ptr = Global.allocate(layout)?; - Ok(RawVec::from_raw_parts_in(ptr.as_mut_ptr() as *mut _, len, Global).into_box(len)) - } + Global.allocate(layout)?.cast() + }; + unsafe { Ok(RawVec::from_raw_parts_in(ptr.as_ptr(), len, Global).into_box(len)) } } /// Constructs a new boxed slice with uninitialized contents, with the memory @@ -711,14 +721,16 @@ impl<T> Box<[T]> { #[unstable(feature = "allocator_api", issue = "32838")] #[inline] pub fn try_new_zeroed_slice(len: usize) -> Result<Box<[mem::MaybeUninit<T>]>, AllocError> { - unsafe { + let ptr = if T::IS_ZST || len == 0 { + NonNull::dangling() + } else { let layout = match Layout::array::<mem::MaybeUninit<T>>(len) { Ok(l) => l, Err(_) => return Err(AllocError), }; - let ptr = Global.allocate_zeroed(layout)?; - Ok(RawVec::from_raw_parts_in(ptr.as_mut_ptr() as *mut _, len, Global).into_box(len)) - } + Global.allocate_zeroed(layout)?.cast() + }; + unsafe { Ok(RawVec::from_raw_parts_in(ptr.as_ptr(), len, Global).into_box(len)) } } } @@ -1215,8 +1227,18 @@ impl<T: ?Sized, A: Allocator> Box<T, A> { #[stable(feature = "rust1", since = "1.0.0")] unsafe impl<#[may_dangle] T: ?Sized, A: Allocator> Drop for Box<T, A> { + #[inline] fn drop(&mut self) { - // FIXME: Do nothing, drop is currently performed by compiler. + // the T in the Box is dropped by the compiler before the destructor is run + + let ptr = self.0; + + unsafe { + let layout = Layout::for_value_raw(ptr.as_ptr()); + if layout.size() != 0 { + self.1.deallocate(From::from(ptr.cast()), layout); + } + } } } @@ -2165,7 +2187,7 @@ impl dyn Error + Send { let err: Box<dyn Error> = self; <dyn Error>::downcast(err).map_err(|s| unsafe { // Reapply the `Send` marker. - mem::transmute::<Box<dyn Error>, Box<dyn Error + Send>>(s) + Box::from_raw(Box::into_raw(s) as *mut (dyn Error + Send)) }) } } @@ -2179,7 +2201,7 @@ impl dyn Error + Send + Sync { let err: Box<dyn Error> = self; <dyn Error>::downcast(err).map_err(|s| unsafe { // Reapply the `Send + Sync` marker. - mem::transmute::<Box<dyn Error>, Box<dyn Error + Send + Sync>>(s) + Box::from_raw(Box::into_raw(s) as *mut (dyn Error + Send + Sync)) }) } } diff --git a/rust/alloc/lib.rs b/rust/alloc/lib.rs index 85e91356ecb3..73b9ffd845d9 100644 --- a/rust/alloc/lib.rs +++ b/rust/alloc/lib.rs @@ -58,6 +58,11 @@ //! [`Rc`]: rc //! [`RefCell`]: core::cell +// To run alloc tests without x.py without ending up with two copies of alloc, Miri needs to be +// able to "empty" this crate. See <https://github.com/rust-lang/miri-test-libstd/issues/4>. +// rustc itself never sets the feature, so this line has no effect there. +#![cfg(any(not(feature = "miri-test-libstd"), test, doctest))] +// #![allow(unused_attributes)] #![stable(feature = "alloc", since = "1.36.0")] #![doc( @@ -77,11 +82,6 @@ ))] #![no_std] #![needs_allocator] -// To run alloc tests without x.py without ending up with two copies of alloc, Miri needs to be -// able to "empty" this crate. See <https://github.com/rust-lang/miri-test-libstd/issues/4>. -// rustc itself never sets the feature, so this line has no affect there. -#![cfg(any(not(feature = "miri-test-libstd"), test, doctest))] -// // Lints: #![deny(unsafe_op_in_unsafe_fn)] #![deny(fuzzy_provenance_casts)] @@ -90,6 +90,8 @@ #![warn(missing_docs)] #![allow(explicit_outlives_requirements)] #![warn(multiple_supertrait_upcastable)] +#![cfg_attr(not(bootstrap), allow(internal_features))] +#![cfg_attr(not(bootstrap), allow(rustdoc::redundant_explicit_links))] // // Library features: // tidy-alphabetical-start @@ -139,7 +141,6 @@ #![feature(maybe_uninit_uninit_array_transpose)] #![feature(pattern)] #![feature(pointer_byte_offsets)] -#![feature(provide_any)] #![feature(ptr_internals)] #![feature(ptr_metadata)] #![feature(ptr_sub_ptr)] diff --git a/rust/alloc/raw_vec.rs b/rust/alloc/raw_vec.rs index 65d5ce15828e..a7425582a323 100644 --- a/rust/alloc/raw_vec.rs +++ b/rust/alloc/raw_vec.rs @@ -471,16 +471,26 @@ impl<T, A: Allocator> RawVec<T, A> { let (ptr, layout) = if let Some(mem) = self.current_memory() { mem } else { return Ok(()) }; // See current_memory() why this assert is here let _: () = const { assert!(mem::size_of::<T>() % mem::align_of::<T>() == 0) }; - let ptr = unsafe { - // `Layout::array` cannot overflow here because it would have - // overflowed earlier when capacity was larger. - let new_size = mem::size_of::<T>().unchecked_mul(cap); - let new_layout = Layout::from_size_align_unchecked(new_size, layout.align()); - self.alloc - .shrink(ptr, layout, new_layout) - .map_err(|_| AllocError { layout: new_layout, non_exhaustive: () })? - }; - self.set_ptr_and_cap(ptr, cap); + + // If shrinking to 0, deallocate the buffer. We don't reach this point + // for the T::IS_ZST case since current_memory() will have returned + // None. + if cap == 0 { + unsafe { self.alloc.deallocate(ptr, layout) }; + self.ptr = Unique::dangling(); + self.cap = 0; + } else { + let ptr = unsafe { + // `Layout::array` cannot overflow here because it would have + // overflowed earlier when capacity was larger. + let new_size = mem::size_of::<T>().unchecked_mul(cap); + let new_layout = Layout::from_size_align_unchecked(new_size, layout.align()); + self.alloc + .shrink(ptr, layout, new_layout) + .map_err(|_| AllocError { layout: new_layout, non_exhaustive: () })? + }; + self.set_ptr_and_cap(ptr, cap); + } Ok(()) } } diff --git a/rust/alloc/vec/drain_filter.rs b/rust/alloc/vec/drain_filter.rs deleted file mode 100644 index 09efff090e42..000000000000 --- a/rust/alloc/vec/drain_filter.rs +++ /dev/null @@ -1,199 +0,0 @@ -// SPDX-License-Identifier: Apache-2.0 OR MIT - -use crate::alloc::{Allocator, Global}; -use core::mem::{ManuallyDrop, SizedTypeProperties}; -use core::ptr; -use core::slice; - -use super::Vec; - -/// An iterator which uses a closure to determine if an element should be removed. -/// -/// This struct is created by [`Vec::drain_filter`]. -/// See its documentation for more. -/// -/// # Example -/// -/// ``` -/// #![feature(drain_filter)] -/// -/// let mut v = vec![0, 1, 2]; -/// let iter: std::vec::DrainFilter<'_, _, _> = v.drain_filter(|x| *x % 2 == 0); -/// ``` -#[unstable(feature = "drain_filter", reason = "recently added", issue = "43244")] -#[derive(Debug)] -pub struct DrainFilter< - 'a, - T, - F, - #[unstable(feature = "allocator_api", issue = "32838")] A: Allocator = Global, -> where - F: FnMut(&mut T) -> bool, -{ - pub(super) vec: &'a mut Vec<T, A>, - /// The index of the item that will be inspected by the next call to `next`. - pub(super) idx: usize, - /// The number of items that have been drained (removed) thus far. - pub(super) del: usize, - /// The original length of `vec` prior to draining. - pub(super) old_len: usize, - /// The filter test predicate. - pub(super) pred: F, - /// A flag that indicates a panic has occurred in the filter test predicate. - /// This is used as a hint in the drop implementation to prevent consumption - /// of the remainder of the `DrainFilter`. Any unprocessed items will be - /// backshifted in the `vec`, but no further items will be dropped or - /// tested by the filter predicate. - pub(super) panic_flag: bool, -} - -impl<T, F, A: Allocator> DrainFilter<'_, T, F, A> -where - F: FnMut(&mut T) -> bool, -{ - /// Returns a reference to the underlying allocator. - #[unstable(feature = "allocator_api", issue = "32838")] - #[inline] - pub fn allocator(&self) -> &A { - self.vec.allocator() - } - - /// Keep unyielded elements in the source `Vec`. - /// - /// # Examples - /// - /// ``` - /// #![feature(drain_filter)] - /// #![feature(drain_keep_rest)] - /// - /// let mut vec = vec!['a', 'b', 'c']; - /// let mut drain = vec.drain_filter(|_| true); - /// - /// assert_eq!(drain.next().unwrap(), 'a'); - /// - /// // This call keeps 'b' and 'c' in the vec. - /// drain.keep_rest(); - /// - /// // If we wouldn't call `keep_rest()`, - /// // `vec` would be empty. - /// assert_eq!(vec, ['b', 'c']); - /// ``` - #[unstable(feature = "drain_keep_rest", issue = "101122")] - pub fn keep_rest(self) { - // At this moment layout looks like this: - // - // _____________________/-- old_len - // / \ - // [kept] [yielded] [tail] - // \_______/ ^-- idx - // \-- del - // - // Normally `Drop` impl would drop [tail] (via .for_each(drop), ie still calling `pred`) - // - // 1. Move [tail] after [kept] - // 2. Update length of the original vec to `old_len - del` - // a. In case of ZST, this is the only thing we want to do - // 3. Do *not* drop self, as everything is put in a consistent state already, there is nothing to do - let mut this = ManuallyDrop::new(self); - - unsafe { - // ZSTs have no identity, so we don't need to move them around. - if !T::IS_ZST && this.idx < this.old_len && this.del > 0 { - let ptr = this.vec.as_mut_ptr(); - let src = ptr.add(this.idx); - let dst = src.sub(this.del); - let tail_len = this.old_len - this.idx; - src.copy_to(dst, tail_len); - } - - let new_len = this.old_len - this.del; - this.vec.set_len(new_len); - } - } -} - -#[unstable(feature = "drain_filter", reason = "recently added", issue = "43244")] -impl<T, F, A: Allocator> Iterator for DrainFilter<'_, T, F, A> -where - F: FnMut(&mut T) -> bool, -{ - type Item = T; - - fn next(&mut self) -> Option<T> { - unsafe { - while self.idx < self.old_len { - let i = self.idx; - let v = slice::from_raw_parts_mut(self.vec.as_mut_ptr(), self.old_len); - self.panic_flag = true; - let drained = (self.pred)(&mut v[i]); - self.panic_flag = false; - // Update the index *after* the predicate is called. If the index - // is updated prior and the predicate panics, the element at this - // index would be leaked. - self.idx += 1; - if drained { - self.del += 1; - return Some(ptr::read(&v[i])); - } else if self.del > 0 { - let del = self.del; - let src: *const T = &v[i]; - let dst: *mut T = &mut v[i - del]; - ptr::copy_nonoverlapping(src, dst, 1); - } - } - None - } - } - - fn size_hint(&self) -> (usize, Option<usize>) { - (0, Some(self.old_len - self.idx)) - } -} - -#[unstable(feature = "drain_filter", reason = "recently added", issue = "43244")] -impl<T, F, A: Allocator> Drop for DrainFilter<'_, T, F, A> -where - F: FnMut(&mut T) -> bool, -{ - fn drop(&mut self) { - struct BackshiftOnDrop<'a, 'b, T, F, A: Allocator> - where - F: FnMut(&mut T) -> bool, - { - drain: &'b mut DrainFilter<'a, T, F, A>, - } - - impl<'a, 'b, T, F, A: Allocator> Drop for BackshiftOnDrop<'a, 'b, T, F, A> - where - F: FnMut(&mut T) -> bool, - { - fn drop(&mut self) { - unsafe { - if self.drain.idx < self.drain.old_len && self.drain.del > 0 { - // This is a pretty messed up state, and there isn't really an - // obviously right thing to do. We don't want to keep trying - // to execute `pred`, so we just backshift all the unprocessed - // elements and tell the vec that they still exist. The backshift - // is required to prevent a double-drop of the last successfully - // drained item prior to a panic in the predicate. - let ptr = self.drain.vec.as_mut_ptr(); - let src = ptr.add(self.drain.idx); - let dst = src.sub(self.drain.del); - let tail_len = self.drain.old_len - self.drain.idx; - src.copy_to(dst, tail_len); - } - self.drain.vec.set_len(self.drain.old_len - self.drain.del); - } - } - } - - let backshift = BackshiftOnDrop { drain: self }; - - // Attempt to consume any remaining elements if the filter predicate - // has not yet panicked. We'll backshift any remaining elements - // whether we've already panicked or if the consumption here panics. - if !backshift.drain.panic_flag { - backshift.drain.for_each(drop); - } - } -} diff --git a/rust/alloc/vec/extract_if.rs b/rust/alloc/vec/extract_if.rs new file mode 100644 index 000000000000..f314a51d4d3d --- /dev/null +++ b/rust/alloc/vec/extract_if.rs @@ -0,0 +1,115 @@ +// SPDX-License-Identifier: Apache-2.0 OR MIT + +use crate::alloc::{Allocator, Global}; +use core::ptr; +use core::slice; + +use super::Vec; + +/// An iterator which uses a closure to determine if an element should be removed. +/// +/// This struct is created by [`Vec::extract_if`]. +/// See its documentation for more. +/// +/// # Example +/// +/// ``` +/// #![feature(extract_if)] +/// +/// let mut v = vec![0, 1, 2]; +/// let iter: std::vec::ExtractIf<'_, _, _> = v.extract_if(|x| *x % 2 == 0); +/// ``` +#[unstable(feature = "extract_if", reason = "recently added", issue = "43244")] +#[derive(Debug)] +#[must_use = "iterators are lazy and do nothing unless consumed"] +pub struct ExtractIf< + 'a, + T, + F, + #[unstable(feature = "allocator_api", issue = "32838")] A: Allocator = Global, +> where + F: FnMut(&mut T) -> bool, +{ + pub(super) vec: &'a mut Vec<T, A>, + /// The index of the item that will be inspected by the next call to `next`. + pub(super) idx: usize, + /// The number of items that have been drained (removed) thus far. + pub(super) del: usize, + /// The original length of `vec` prior to draining. + pub(super) old_len: usize, + /// The filter test predicate. + pub(super) pred: F, +} + +impl<T, F, A: Allocator> ExtractIf<'_, T, F, A> +where + F: FnMut(&mut T) -> bool, +{ + /// Returns a reference to the underlying allocator. + #[unstable(feature = "allocator_api", issue = "32838")] + #[inline] + pub fn allocator(&self) -> &A { + self.vec.allocator() + } +} + +#[unstable(feature = "extract_if", reason = "recently added", issue = "43244")] +impl<T, F, A: Allocator> Iterator for ExtractIf<'_, T, F, A> +where + F: FnMut(&mut T) -> bool, +{ + type Item = T; + + fn next(&mut self) -> Option<T> { + unsafe { + while self.idx < self.old_len { + let i = self.idx; + let v = slice::from_raw_parts_mut(self.vec.as_mut_ptr(), self.old_len); + let drained = (self.pred)(&mut v[i]); + // Update the index *after* the predicate is called. If the index + // is updated prior and the predicate panics, the element at this + // index would be leaked. + self.idx += 1; + if drained { + self.del += 1; + return Some(ptr::read(&v[i])); + } else if self.del > 0 { + let del = self.del; + let src: *const T = &v[i]; + let dst: *mut T = &mut v[i - del]; + ptr::copy_nonoverlapping(src, dst, 1); + } + } + None + } + } + + fn size_hint(&self) -> (usize, Option<usize>) { + (0, Some(self.old_len - self.idx)) + } +} + +#[unstable(feature = "extract_if", reason = "recently added", issue = "43244")] +impl<T, F, A: Allocator> Drop for ExtractIf<'_, T, F, A> +where + F: FnMut(&mut T) -> bool, +{ + fn drop(&mut self) { + unsafe { + if self.idx < self.old_len && self.del > 0 { + // This is a pretty messed up state, and there isn't really an + // obviously right thing to do. We don't want to keep trying + // to execute `pred`, so we just backshift all the unprocessed + // elements and tell the vec that they still exist. The backshift + // is required to prevent a double-drop of the last successfully + // drained item prior to a panic in the predicate. + let ptr = self.vec.as_mut_ptr(); + let src = ptr.add(self.idx); + let dst = src.sub(self.del); + let tail_len = self.old_len - self.idx; + src.copy_to(dst, tail_len); + } + self.vec.set_len(self.old_len - self.del); + } + } +} diff --git a/rust/alloc/vec/mod.rs b/rust/alloc/vec/mod.rs index 05c70de0227e..209a88cfe598 100644 --- a/rust/alloc/vec/mod.rs +++ b/rust/alloc/vec/mod.rs @@ -74,10 +74,10 @@ use crate::boxed::Box; use crate::collections::{TryReserveError, TryReserveErrorKind}; use crate::raw_vec::RawVec; -#[unstable(feature = "drain_filter", reason = "recently added", issue = "43244")] -pub use self::drain_filter::DrainFilter; +#[unstable(feature = "extract_if", reason = "recently added", issue = "43244")] +pub use self::extract_if::ExtractIf; -mod drain_filter; +mod extract_if; #[cfg(not(no_global_oom_handling))] #[stable(feature = "vec_splice", since = "1.21.0")] @@ -216,7 +216,7 @@ mod spec_extend; /// /// # Indexing /// -/// The `Vec` type allows to access values by index, because it implements the +/// The `Vec` type allows access to values by index, because it implements the /// [`Index`] trait. An example will be more explicit: /// /// ``` @@ -618,22 +618,20 @@ impl<T> Vec<T> { /// Using memory that was allocated elsewhere: /// /// ```rust - /// #![feature(allocator_api)] - /// - /// use std::alloc::{AllocError, Allocator, Global, Layout}; + /// use std::alloc::{alloc, Layout}; /// /// fn main() { /// let layout = Layout::array::<u32>(16).expect("overflow cannot happen"); /// /// let vec = unsafe { - /// let mem = match Global.allocate(layout) { - /// Ok(mem) => mem.cast::<u32>().as_ptr(), - /// Err(AllocError) => return, - /// }; + /// let mem = alloc(layout).cast::<u32>(); + /// if mem.is_null() { + /// return; + /// } /// /// mem.write(1_000_000); /// - /// Vec::from_raw_parts_in(mem, 1, 16, Global) + /// Vec::from_raw_parts(mem, 1, 16) /// }; /// /// assert_eq!(vec, &[1_000_000]); @@ -876,19 +874,22 @@ impl<T, A: Allocator> Vec<T, A> { /// Using memory that was allocated elsewhere: /// /// ```rust - /// use std::alloc::{alloc, Layout}; + /// #![feature(allocator_api)] + /// + /// use std::alloc::{AllocError, Allocator, Global, Layout}; /// /// fn main() { /// let layout = Layout::array::<u32>(16).expect("overflow cannot happen"); + /// /// let vec = unsafe { - /// let mem = alloc(layout).cast::<u32>(); - /// if mem.is_null() { - /// return; - /// } + /// let mem = match Global.allocate(layout) { + /// Ok(mem) => mem.cast::<u32>().as_ptr(), + /// Err(AllocError) => return, + /// }; /// /// mem.write(1_000_000); /// - /// Vec::from_raw_parts(mem, 1, 16) + /// Vec::from_raw_parts_in(mem, 1, 16, Global) /// }; /// /// assert_eq!(vec, &[1_000_000]); @@ -2507,7 +2508,7 @@ impl<T: Clone, A: Allocator> Vec<T, A> { let len = self.len(); if new_len > len { - self.extend_with(new_len - len, ExtendElement(value)) + self.extend_with(new_len - len, value) } else { self.truncate(new_len); } @@ -2545,7 +2546,7 @@ impl<T: Clone, A: Allocator> Vec<T, A> { let len = self.len(); if new_len > len { - self.try_extend_with(new_len - len, ExtendElement(value)) + self.try_extend_with(new_len - len, value) } else { self.truncate(new_len); Ok(()) @@ -2684,26 +2685,10 @@ impl<T, A: Allocator, const N: usize> Vec<[T; N], A> { } } -// This code generalizes `extend_with_{element,default}`. -trait ExtendWith<T> { - fn next(&mut self) -> T; - fn last(self) -> T; -} - -struct ExtendElement<T>(T); -impl<T: Clone> ExtendWith<T> for ExtendElement<T> { - fn next(&mut self) -> T { - self.0.clone() - } - fn last(self) -> T { - self.0 - } -} - -impl<T, A: Allocator> Vec<T, A> { +impl<T: Clone, A: Allocator> Vec<T, A> { #[cfg(not(no_global_oom_handling))] - /// Extend the vector by `n` values, using the given generator. - fn extend_with<E: ExtendWith<T>>(&mut self, n: usize, mut value: E) { + /// Extend the vector by `n` clones of value. + fn extend_with(&mut self, n: usize, value: T) { self.reserve(n); unsafe { @@ -2715,15 +2700,15 @@ impl<T, A: Allocator> Vec<T, A> { // Write all elements except the last one for _ in 1..n { - ptr::write(ptr, value.next()); + ptr::write(ptr, value.clone()); ptr = ptr.add(1); - // Increment the length in every step in case next() panics + // Increment the length in every step in case clone() panics local_len.increment_len(1); } if n > 0 { // We can write the last element directly without cloning needlessly - ptr::write(ptr, value.last()); + ptr::write(ptr, value); local_len.increment_len(1); } @@ -2731,8 +2716,8 @@ impl<T, A: Allocator> Vec<T, A> { } } - /// Try to extend the vector by `n` values, using the given generator. - fn try_extend_with<E: ExtendWith<T>>(&mut self, n: usize, mut value: E) -> Result<(), TryReserveError> { + /// Try to extend the vector by `n` clones of value. + fn try_extend_with(&mut self, n: usize, value: T) -> Result<(), TryReserveError> { self.try_reserve(n)?; unsafe { @@ -2744,15 +2729,15 @@ impl<T, A: Allocator> Vec<T, A> { // Write all elements except the last one for _ in 1..n { - ptr::write(ptr, value.next()); + ptr::write(ptr, value.clone()); ptr = ptr.add(1); - // Increment the length in every step in case next() panics + // Increment the length in every step in case clone() panics local_len.increment_len(1); } if n > 0 { // We can write the last element directly without cloning needlessly - ptr::write(ptr, value.last()); + ptr::write(ptr, value); local_len.increment_len(1); } @@ -3210,6 +3195,12 @@ impl<T, A: Allocator> Vec<T, A> { /// If the closure returns false, the element will remain in the vector and will not be yielded /// by the iterator. /// + /// If the returned `ExtractIf` is not exhausted, e.g. because it is dropped without iterating + /// or the iteration short-circuits, then the remaining elements will be retained. + /// Use [`retain`] with a negated predicate if you do not need the returned iterator. + /// + /// [`retain`]: Vec::retain + /// /// Using this method is equivalent to the following code: /// /// ``` @@ -3228,10 +3219,10 @@ impl<T, A: Allocator> Vec<T, A> { /// # assert_eq!(vec, vec![1, 4, 5]); /// ``` /// - /// But `drain_filter` is easier to use. `drain_filter` is also more efficient, + /// But `extract_if` is easier to use. `extract_if` is also more efficient, /// because it can backshift the elements of the array in bulk. /// - /// Note that `drain_filter` also lets you mutate every element in the filter closure, + /// Note that `extract_if` also lets you mutate every element in the filter closure, /// regardless of whether you choose to keep or remove it. /// /// # Examples @@ -3239,17 +3230,17 @@ impl<T, A: Allocator> Vec<T, A> { /// Splitting an array into evens and odds, reusing the original allocation: /// /// ``` - /// #![feature(drain_filter)] + /// #![feature(extract_if)] /// let mut numbers = vec![1, 2, 3, 4, 5, 6, 8, 9, 11, 13, 14, 15]; /// - /// let evens = numbers.drain_filter(|x| *x % 2 == 0).collect::<Vec<_>>(); + /// let evens = numbers.extract_if(|x| *x % 2 == 0).collect::<Vec<_>>(); /// let odds = numbers; /// /// assert_eq!(evens, vec![2, 4, 6, 8, 14]); /// assert_eq!(odds, vec![1, 3, 5, 9, 11, 13, 15]); /// ``` - #[unstable(feature = "drain_filter", reason = "recently added", issue = "43244")] - pub fn drain_filter<F>(&mut self, filter: F) -> DrainFilter<'_, T, F, A> + #[unstable(feature = "extract_if", reason = "recently added", issue = "43244")] + pub fn extract_if<F>(&mut self, filter: F) -> ExtractIf<'_, T, F, A> where F: FnMut(&mut T) -> bool, { @@ -3260,7 +3251,7 @@ impl<T, A: Allocator> Vec<T, A> { self.set_len(0); } - DrainFilter { vec: self, idx: 0, del: 0, old_len, pred: filter, panic_flag: false } + ExtractIf { vec: self, idx: 0, del: 0, old_len, pred: filter } } } @@ -3272,7 +3263,7 @@ impl<T, A: Allocator> Vec<T, A> { /// [`copy_from_slice`]: slice::copy_from_slice #[cfg(not(no_global_oom_handling))] #[stable(feature = "extend_ref", since = "1.2.0")] -impl<'a, T: Copy + 'a, A: Allocator + 'a> Extend<&'a T> for Vec<T, A> { +impl<'a, T: Copy + 'a, A: Allocator> Extend<&'a T> for Vec<T, A> { fn extend<I: IntoIterator<Item = &'a T>>(&mut self, iter: I) { self.spec_extend(iter.into_iter()) } @@ -3290,9 +3281,14 @@ impl<'a, T: Copy + 'a, A: Allocator + 'a> Extend<&'a T> for Vec<T, A> { /// Implements comparison of vectors, [lexicographically](Ord#lexicographical-comparison). #[stable(feature = "rust1", since = "1.0.0")] -impl<T: PartialOrd, A: Allocator> PartialOrd for Vec<T, A> { +impl<T, A1, A2> PartialOrd<Vec<T, A2>> for Vec<T, A1> +where + T: PartialOrd, + A1: Allocator, + A2: Allocator, +{ #[inline] - fn partial_cmp(&self, other: &Self) -> Option<Ordering> { + fn partial_cmp(&self, other: &Vec<T, A2>) -> Option<Ordering> { PartialOrd::partial_cmp(&**self, &**other) } } diff --git a/rust/alloc/vec/spec_extend.rs b/rust/alloc/vec/spec_extend.rs index a6a735201e59..ada919537446 100644 --- a/rust/alloc/vec/spec_extend.rs +++ b/rust/alloc/vec/spec_extend.rs @@ -77,7 +77,7 @@ impl<T, A: Allocator> TrySpecExtend<T, IntoIter<T>> for Vec<T, A> { } #[cfg(not(no_global_oom_handling))] -impl<'a, T: 'a, I, A: Allocator + 'a> SpecExtend<&'a T, I> for Vec<T, A> +impl<'a, T: 'a, I, A: Allocator> SpecExtend<&'a T, I> for Vec<T, A> where I: Iterator<Item = &'a T>, T: Clone, @@ -87,7 +87,7 @@ where } } -impl<'a, T: 'a, I, A: Allocator + 'a> TrySpecExtend<&'a T, I> for Vec<T, A> +impl<'a, T: 'a, I, A: Allocator> TrySpecExtend<&'a T, I> for Vec<T, A> where I: Iterator<Item = &'a T>, T: Clone, @@ -98,7 +98,7 @@ where } #[cfg(not(no_global_oom_handling))] -impl<'a, T: 'a, A: Allocator + 'a> SpecExtend<&'a T, slice::Iter<'a, T>> for Vec<T, A> +impl<'a, T: 'a, A: Allocator> SpecExtend<&'a T, slice::Iter<'a, T>> for Vec<T, A> where T: Copy, { @@ -108,7 +108,7 @@ where } } -impl<'a, T: 'a, A: Allocator + 'a> TrySpecExtend<&'a T, slice::Iter<'a, T>> for Vec<T, A> +impl<'a, T: 'a, A: Allocator> TrySpecExtend<&'a T, slice::Iter<'a, T>> for Vec<T, A> where T: Copy, { diff --git a/rust/compiler_builtins.rs b/rust/compiler_builtins.rs index fb8ac3f211de..bba2922c6ef7 100644 --- a/rust/compiler_builtins.rs +++ b/rust/compiler_builtins.rs @@ -19,6 +19,7 @@ //! [`compiler_builtins`]: https://github.com/rust-lang/compiler-builtins //! [`compiler-rt`]: https://compiler-rt.llvm.org/ +#![allow(internal_features)] #![feature(compiler_builtins)] #![compiler_builtins] #![no_builtins] diff --git a/rust/kernel/init.rs b/rust/kernel/init.rs index 4ebb6f23fc2e..65be9ae57b80 100644 --- a/rust/kernel/init.rs +++ b/rust/kernel/init.rs @@ -35,7 +35,7 @@ //! that you need to write `<-` instead of `:` for fields that you want to initialize in-place. //! //! ```rust -//! # #![allow(clippy::disallowed_names, clippy::new_ret_no_self)] +//! # #![allow(clippy::disallowed_names)] //! use kernel::{prelude::*, sync::Mutex, new_mutex}; //! # use core::pin::Pin; //! #[pin_data] @@ -55,7 +55,7 @@ //! (or just the stack) to actually initialize a `Foo`: //! //! ```rust -//! # #![allow(clippy::disallowed_names, clippy::new_ret_no_self)] +//! # #![allow(clippy::disallowed_names)] //! # use kernel::{prelude::*, sync::Mutex, new_mutex}; //! # use core::pin::Pin; //! # #[pin_data] @@ -86,7 +86,7 @@ //! To declare an init macro/function you just return an [`impl PinInit<T, E>`]: //! //! ```rust -//! # #![allow(clippy::disallowed_names, clippy::new_ret_no_self)] +//! # #![allow(clippy::disallowed_names)] //! # use kernel::{sync::Mutex, prelude::*, new_mutex, init::PinInit, try_pin_init}; //! #[pin_data] //! struct DriverData { @@ -236,7 +236,7 @@ pub mod macros; /// # Examples /// /// ```rust -/// # #![allow(clippy::disallowed_names, clippy::new_ret_no_self)] +/// # #![allow(clippy::disallowed_names)] /// # use kernel::{init, macros::pin_data, pin_init, stack_pin_init, init::*, sync::Mutex, new_mutex}; /// # use core::pin::Pin; /// #[pin_data] @@ -288,7 +288,7 @@ macro_rules! stack_pin_init { /// # Examples /// /// ```rust,ignore -/// # #![allow(clippy::disallowed_names, clippy::new_ret_no_self)] +/// # #![allow(clippy::disallowed_names)] /// # use kernel::{init, pin_init, stack_try_pin_init, init::*, sync::Mutex, new_mutex}; /// # use macros::pin_data; /// # use core::{alloc::AllocError, pin::Pin}; @@ -314,7 +314,7 @@ macro_rules! stack_pin_init { /// ``` /// /// ```rust,ignore -/// # #![allow(clippy::disallowed_names, clippy::new_ret_no_self)] +/// # #![allow(clippy::disallowed_names)] /// # use kernel::{init, pin_init, stack_try_pin_init, init::*, sync::Mutex, new_mutex}; /// # use macros::pin_data; /// # use core::{alloc::AllocError, pin::Pin}; @@ -366,7 +366,7 @@ macro_rules! stack_try_pin_init { /// The syntax is almost identical to that of a normal `struct` initializer: /// /// ```rust -/// # #![allow(clippy::disallowed_names, clippy::new_ret_no_self)] +/// # #![allow(clippy::disallowed_names)] /// # use kernel::{init, pin_init, macros::pin_data, init::*}; /// # use core::pin::Pin; /// #[pin_data] @@ -411,7 +411,7 @@ macro_rules! stack_try_pin_init { /// To create an initializer function, simply declare it like this: /// /// ```rust -/// # #![allow(clippy::disallowed_names, clippy::new_ret_no_self)] +/// # #![allow(clippy::disallowed_names)] /// # use kernel::{init, pin_init, prelude::*, init::*}; /// # use core::pin::Pin; /// # #[pin_data] @@ -438,7 +438,7 @@ macro_rules! stack_try_pin_init { /// Users of `Foo` can now create it like this: /// /// ```rust -/// # #![allow(clippy::disallowed_names, clippy::new_ret_no_self)] +/// # #![allow(clippy::disallowed_names)] /// # use kernel::{init, pin_init, macros::pin_data, init::*}; /// # use core::pin::Pin; /// # #[pin_data] @@ -466,7 +466,7 @@ macro_rules! stack_try_pin_init { /// They can also easily embed it into their own `struct`s: /// /// ```rust -/// # #![allow(clippy::disallowed_names, clippy::new_ret_no_self)] +/// # #![allow(clippy::disallowed_names)] /// # use kernel::{init, pin_init, macros::pin_data, init::*}; /// # use core::pin::Pin; /// # #[pin_data] diff --git a/rust/kernel/print.rs b/rust/kernel/print.rs index 8009184bf6d7..f48926e3e9fe 100644 --- a/rust/kernel/print.rs +++ b/rust/kernel/print.rs @@ -399,6 +399,7 @@ macro_rules! pr_debug ( /// Mimics the interface of [`std::print!`]. See [`core::fmt`] and /// `alloc::format!` for information about the formatting syntax. /// +/// [`pr_info!`]: crate::pr_info! /// [`pr_cont`]: https://www.kernel.org/doc/html/latest/core-api/printk-basics.html#c.pr_cont /// [`std::print!`]: https://doc.rust-lang.org/std/macro.print.html /// diff --git a/rust/kernel/sync/arc.rs b/rust/kernel/sync/arc.rs index 3d496391a9bd..7f04e4f00a2c 100644 --- a/rust/kernel/sync/arc.rs +++ b/rust/kernel/sync/arc.rs @@ -302,7 +302,7 @@ impl<T: ?Sized> Drop for Arc<T> { // The count reached zero, we must free the memory. // // SAFETY: The pointer was initialised from the result of `Box::leak`. - unsafe { Box::from_raw(self.ptr.as_ptr()) }; + unsafe { drop(Box::from_raw(self.ptr.as_ptr())) }; } } } diff --git a/rust/kernel/sync/condvar.rs b/rust/kernel/sync/condvar.rs index ed353399c4e5..b679b6f6dbeb 100644 --- a/rust/kernel/sync/condvar.rs +++ b/rust/kernel/sync/condvar.rs @@ -91,7 +91,6 @@ unsafe impl Sync for CondVar {} impl CondVar { /// Constructs a new condvar initialiser. - #[allow(clippy::new_ret_no_self)] pub fn new(name: &'static CStr, key: &'static LockClassKey) -> impl PinInit<Self> { pin_init!(Self { _pin: PhantomPinned, diff --git a/rust/kernel/sync/lock.rs b/rust/kernel/sync/lock.rs index 70a785f04754..f12a684bc957 100644 --- a/rust/kernel/sync/lock.rs +++ b/rust/kernel/sync/lock.rs @@ -99,7 +99,6 @@ unsafe impl<T: ?Sized + Send, B: Backend> Sync for Lock<T, B> {} impl<T, B: Backend> Lock<T, B> { /// Constructs a new lock initialiser. - #[allow(clippy::new_ret_no_self)] pub fn new(t: T, name: &'static CStr, key: &'static LockClassKey) -> impl PinInit<Self> { pin_init!(Self { data: UnsafeCell::new(t), diff --git a/rust/kernel/task.rs b/rust/kernel/task.rs index 7eda15e5f1b3..b2299bc7ac1f 100644 --- a/rust/kernel/task.rs +++ b/rust/kernel/task.rs @@ -82,7 +82,7 @@ impl Task { /// Returns a task reference for the currently executing task/thread. /// /// The recommended way to get the current task/thread is to use the - /// [`current`](crate::current) macro because it is safe. + /// [`current`] macro because it is safe. /// /// # Safety /// |