From nobody Thu Nov 28 15:37:30 2024 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D67801CBEA9; Tue, 1 Oct 2024 15:02:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727794967; cv=none; b=b1U/sMdgP/lKZEXoh8y14g6q2XYQmgyBqMF80d561WUm/ucGL9iLhbmk87Nx8Hrxn0S4NKOAsb5tJP8W+AO0ghcvh/4qCEidO3LqenoDKSX0Mwzcfgztt33m2s8Wu+kQ/Vp1agPtk7v6bsx5dmLG0wnMQknyNSVW7vswEpIcKag= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727794967; c=relaxed/simple; bh=cVm78aZuB5Rz7RoLW+2cZZaDXtknlbwGruXhodnZH1E=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=I8+qQ8Y5nuRxaT9feVM1m4tr9JcH9r7cWkIrK3p71UHZDqmHAytFzuq2MeXnRmbXLaGleVUB7YusHpz8oBchx38cNJgax5AuLIiGLliXS+cHwKFldBakPpCUBBFfe35CjVnb/MZOBBp5Lglk2COceJWNBJkPAsm1OcVEeXXMTOo= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=bzOWDfCW; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="bzOWDfCW" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D1CA3C4CED3; Tue, 1 Oct 2024 15:02:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1727794967; bh=cVm78aZuB5Rz7RoLW+2cZZaDXtknlbwGruXhodnZH1E=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bzOWDfCW2+EZ4g+xEC78TbeRCoi7uyLf19fSSO5sQwaUUYrMnKtdjkPGkumh1gSKw cd3sLk7VDVsJdTXwoLpqaYCpqyHSdj35acqM3O7gfSaOeJyvCiwPHd3vX6Mf+pSaii dH0I9VjV5I8PfPQa6vqBYCecxTYPxK/MnyVfhkJsqsbgmod9eYL1EuH025um+nlSEj 6dYPnaueasYavw3VJX+cF7YBXsaTlC/HGjq4+ZH9S0RQwHb037UB9UfM+8sWisnswF ypDgJIJSYfaBOnPGFB2qAquXsHCB85CnftkjfG6pIzfVPMSFG7EzZOuSqlxu0lOuRV mkQQ+Dlx5jB7A== From: Danilo Krummrich To: ojeda@kernel.org, alex.gaynor@gmail.com, wedsonaf@gmail.com, boqun.feng@gmail.com, gary@garyguo.net, bjorn3_gh@protonmail.com, benno.lossin@proton.me, a.hindborg@samsung.com, aliceryhl@google.com, akpm@linux-foundation.org Cc: daniel.almeida@collabora.com, faith.ekstrand@collabora.com, boris.brezillon@collabora.com, lina@asahilina.net, mcanal@igalia.com, zhiw@nvidia.com, cjia@nvidia.com, jhubbard@nvidia.com, airlied@redhat.com, ajanulgu@redhat.com, lyude@redhat.com, linux-kernel@vger.kernel.org, rust-for-linux@vger.kernel.org, linux-mm@kvack.org, Danilo Krummrich Subject: [PATCH v8 28/29] kbuild: rust: remove the `alloc` crate and `GlobalAlloc` Date: Tue, 1 Oct 2024 17:00:03 +0200 Message-ID: <20241001150008.183102-29-dakr@kernel.org> X-Mailer: git-send-email 2.46.1 In-Reply-To: <20241001150008.183102-1-dakr@kernel.org> References: <20241001150008.183102-1-dakr@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Now that we have our own `Allocator`, `Box` and `Vec` types we can remove Rust's `alloc` crate and the `new_uninit` unstable feature. Also remove `Kmalloc`'s `GlobalAlloc` implementation -- we can't remove this in a separate patch, since the `alloc` crate requires a `#[global_allocator]` to set, that implements `GlobalAlloc`. Signed-off-by: Danilo Krummrich --- rust/Makefile | 43 +++++---------------- rust/exports.c | 1 - rust/kernel/alloc/allocator.rs | 63 +------------------------------ scripts/Makefile.build | 7 +--- scripts/generate_rust_analyzer.py | 11 +----- 5 files changed, 15 insertions(+), 110 deletions(-) diff --git a/rust/Makefile b/rust/Makefile index b5e0a73b78f3..16ea0087ce71 100644 --- a/rust/Makefile +++ b/rust/Makefile @@ -15,8 +15,8 @@ always-$(CONFIG_RUST) +=3D libmacros.so no-clean-files +=3D libmacros.so =20 always-$(CONFIG_RUST) +=3D bindings/bindings_generated.rs bindings/binding= s_helpers_generated.rs -obj-$(CONFIG_RUST) +=3D alloc.o bindings.o kernel.o -always-$(CONFIG_RUST) +=3D exports_alloc_generated.h exports_helpers_gener= ated.h \ +obj-$(CONFIG_RUST) +=3D bindings.o kernel.o +always-$(CONFIG_RUST) +=3D exports_helpers_generated.h \ exports_bindings_generated.h exports_kernel_generated.h =20 always-$(CONFIG_RUST) +=3D uapi/uapi_generated.rs @@ -53,11 +53,6 @@ endif core-cfgs =3D \ --cfg no_fp_fmt_parse =20 -alloc-cfgs =3D \ - --cfg no_global_oom_handling \ - --cfg no_rc \ - --cfg no_sync - quiet_cmd_rustdoc =3D RUSTDOC $(if $(rustdoc_host),H, ) $< cmd_rustdoc =3D \ OBJTREE=3D$(abspath $(objtree)) \ @@ -81,7 +76,7 @@ quiet_cmd_rustdoc =3D RUSTDOC $(if $(rustdoc_host),H, ) $< # command-like flags to solve the issue. Meanwhile, we use the non-custom = case # and then retouch the generated files. rustdoc: rustdoc-core rustdoc-macros rustdoc-compiler_builtins \ - rustdoc-alloc rustdoc-kernel + rustdoc-kernel $(Q)cp $(srctree)/Documentation/images/logo.svg $(rustdoc_output)/static.= files/ $(Q)cp $(srctree)/Documentation/images/COPYING-logo $(rustdoc_output)/sta= tic.files/ $(Q)find $(rustdoc_output) -name '*.html' -type f -print0 | xargs -0 sed = -Ei \ @@ -105,20 +100,11 @@ rustdoc-core: $(RUST_LIB_SRC)/core/src/lib.rs FORCE rustdoc-compiler_builtins: $(src)/compiler_builtins.rs rustdoc-core FORCE +$(call if_changed,rustdoc) =20 -# We need to allow `rustdoc::broken_intra_doc_links` because some -# `no_global_oom_handling` functions refer to non-`no_global_oom_handling` -# functions. Ideally `rustdoc` would have a way to distinguish broken links -# due to things that are "configured out" vs. entirely non-existing ones. -rustdoc-alloc: private rustc_target_flags =3D $(alloc-cfgs) \ - -Arustdoc::broken_intra_doc_links -rustdoc-alloc: $(RUST_LIB_SRC)/alloc/src/lib.rs rustdoc-core rustdoc-compi= ler_builtins FORCE - +$(call if_changed,rustdoc) - -rustdoc-kernel: private rustc_target_flags =3D --extern alloc \ +rustdoc-kernel: private rustc_target_flags =3D \ --extern build_error --extern macros=3D$(objtree)/$(obj)/libmacros.so \ --extern bindings --extern uapi rustdoc-kernel: $(src)/kernel/lib.rs rustdoc-core rustdoc-macros \ - rustdoc-compiler_builtins rustdoc-alloc $(obj)/libmacros.so \ + rustdoc-compiler_builtins $(obj)/libmacros.so \ $(obj)/bindings.o FORCE +$(call if_changed,rustdoc) =20 @@ -162,7 +148,7 @@ quiet_cmd_rustdoc_test_kernel =3D RUSTDOC TK $< mkdir -p $(objtree)/$(obj)/test/doctests/kernel; \ OBJTREE=3D$(abspath $(objtree)) \ $(RUSTDOC) --test $(rust_flags) \ - -L$(objtree)/$(obj) --extern alloc --extern kernel \ + -L$(objtree)/$(obj) --extern kernel \ --extern build_error --extern macros \ --extern bindings --extern uapi \ --no-run --crate-name kernel -Zunstable-options \ @@ -198,7 +184,7 @@ rusttest-macros: $(src)/macros/lib.rs FORCE +$(call if_changed,rustc_test) +$(call if_changed,rustdoc_test) =20 -rusttest-kernel: private rustc_target_flags =3D --extern alloc \ +rusttest-kernel: private rustc_target_flags =3D \ --extern build_error --extern macros --extern bindings --extern uapi rusttest-kernel: $(src)/kernel/lib.rs \ rusttestlib-build_error rusttestlib-macros rusttestlib-bindings \ @@ -311,9 +297,6 @@ quiet_cmd_exports =3D EXPORTS $@ $(obj)/exports_core_generated.h: $(obj)/core.o FORCE $(call if_changed,exports) =20 -$(obj)/exports_alloc_generated.h: $(obj)/alloc.o FORCE - $(call if_changed,exports) - # Even though Rust kernel modules should never use the bindings directly, # symbols from the `bindings` crate and the C helpers need to be exported # because Rust generics and inlined functions may not get their code gener= ated @@ -360,7 +343,7 @@ quiet_cmd_rustc_library =3D $(if $(skip_clippy),RUSTC,$= (RUSTC_OR_CLIPPY_QUIET)) L =20 rust-analyzer: $(Q)$(srctree)/scripts/generate_rust_analyzer.py \ - --cfgs=3D'core=3D$(core-cfgs)' --cfgs=3D'alloc=3D$(alloc-cfgs)' \ + --cfgs=3D'core=3D$(core-cfgs)' \ $(realpath $(srctree)) $(realpath $(objtree)) \ $(rustc_sysroot) $(RUST_LIB_SRC) $(KBUILD_EXTMOD) > \ $(if $(KBUILD_EXTMOD),$(extmod_prefix),$(objtree))/rust-project.json @@ -398,12 +381,6 @@ $(obj)/compiler_builtins.o: private rustc_objcopy =3D = -w -W '__*' $(obj)/compiler_builtins.o: $(src)/compiler_builtins.rs $(obj)/core.o FORCE +$(call if_changed_rule,rustc_library) =20 -$(obj)/alloc.o: private skip_clippy =3D 1 -$(obj)/alloc.o: private skip_flags =3D -Wunreachable_pub -$(obj)/alloc.o: private rustc_target_flags =3D $(alloc-cfgs) -$(obj)/alloc.o: $(RUST_LIB_SRC)/alloc/src/lib.rs $(obj)/compiler_builtins.= o FORCE - +$(call if_changed_rule,rustc_library) - $(obj)/build_error.o: $(src)/build_error.rs $(obj)/compiler_builtins.o FOR= CE +$(call if_changed_rule,rustc_library) =20 @@ -418,9 +395,9 @@ $(obj)/uapi.o: $(src)/uapi/lib.rs \ $(obj)/uapi/uapi_generated.rs FORCE +$(call if_changed_rule,rustc_library) =20 -$(obj)/kernel.o: private rustc_target_flags =3D --extern alloc \ +$(obj)/kernel.o: private rustc_target_flags =3D \ --extern build_error --extern macros --extern bindings --extern uapi -$(obj)/kernel.o: $(src)/kernel/lib.rs $(obj)/alloc.o $(obj)/build_error.o \ +$(obj)/kernel.o: $(src)/kernel/lib.rs $(obj)/build_error.o \ $(obj)/libmacros.so $(obj)/bindings.o $(obj)/uapi.o FORCE +$(call if_changed_rule,rustc_library) =20 diff --git a/rust/exports.c b/rust/exports.c index e5695f3b45b7..82a037381798 100644 --- a/rust/exports.c +++ b/rust/exports.c @@ -16,7 +16,6 @@ #define EXPORT_SYMBOL_RUST_GPL(sym) extern int sym; EXPORT_SYMBOL_GPL(sym) =20 #include "exports_core_generated.h" -#include "exports_alloc_generated.h" #include "exports_helpers_generated.h" #include "exports_bindings_generated.h" #include "exports_kernel_generated.h" diff --git a/rust/kernel/alloc/allocator.rs b/rust/kernel/alloc/allocator.rs index d0a8819c6741..067719f11d13 100644 --- a/rust/kernel/alloc/allocator.rs +++ b/rust/kernel/alloc/allocator.rs @@ -8,8 +8,8 @@ //! //! Reference: =20 -use super::{flags::*, Flags}; -use core::alloc::{GlobalAlloc, Layout}; +use super::Flags; +use core::alloc::Layout; use core::ptr; use core::ptr::NonNull; =20 @@ -54,23 +54,6 @@ fn aligned_size(new_layout: Layout) -> usize { layout.size() } =20 -/// Calls `krealloc` with a proper size to alloc a new object aligned to `= new_layout`'s alignment. -/// -/// # Safety -/// -/// - `ptr` can be either null or a pointer which has been allocated by th= is allocator. -/// - `new_layout` must have a non-zero size. -pub(crate) unsafe fn krealloc_aligned(ptr: *mut u8, new_layout: Layout, fl= ags: Flags) -> *mut u8 { - let size =3D aligned_size(new_layout); - - // SAFETY: - // - `ptr` is either null or a pointer returned from a previous `k{re}= alloc()` by the - // function safety requirement. - // - `size` is greater than 0 since it's from `layout.size()` (which c= annot be zero according - // to the function safety requirement) - unsafe { bindings::krealloc(ptr as *const core::ffi::c_void, size, fla= gs.0) as *mut u8 } -} - /// # Invariants /// /// One of the following `krealloc`, `vrealloc`, `kvrealloc`. @@ -156,41 +139,6 @@ unsafe fn realloc( } } =20 -unsafe impl GlobalAlloc for Kmalloc { - unsafe fn alloc(&self, layout: Layout) -> *mut u8 { - // SAFETY: `ptr::null_mut()` is null and `layout` has a non-zero s= ize by the function safety - // requirement. - unsafe { krealloc_aligned(ptr::null_mut(), layout, GFP_KERNEL) } - } - - unsafe fn dealloc(&self, ptr: *mut u8, _layout: Layout) { - unsafe { - bindings::kfree(ptr as *const core::ffi::c_void); - } - } - - unsafe fn realloc(&self, ptr: *mut u8, layout: Layout, new_size: usize= ) -> *mut u8 { - // SAFETY: - // - `new_size`, when rounded up to the nearest multiple of `layou= t.align()`, will not - // overflow `isize` by the function safety requirement. - // - `layout.align()` is a proper alignment (i.e. not zero and mus= t be a power of two). - let layout =3D unsafe { Layout::from_size_align_unchecked(new_size= , layout.align()) }; - - // SAFETY: - // - `ptr` is either null or a pointer allocated by this allocator= by the function safety - // requirement. - // - the size of `layout` is not zero because `new_size` is not ze= ro by the function safety - // requirement. - unsafe { krealloc_aligned(ptr, layout, GFP_KERNEL) } - } - - unsafe fn alloc_zeroed(&self, layout: Layout) -> *mut u8 { - // SAFETY: `ptr::null_mut()` is null and `layout` has a non-zero s= ize by the function safety - // requirement. - unsafe { krealloc_aligned(ptr::null_mut(), layout, GFP_KERNEL | __= GFP_ZERO) } - } -} - // SAFETY: `realloc` delegates to `ReallocFunc::call`, which guarantees th= at // - memory remains valid until it is explicitly freed, // - passing a pointer to a valid memory allocation is OK, @@ -238,10 +186,3 @@ unsafe fn realloc( unsafe { ReallocFunc::KVREALLOC.call(ptr, layout, old_layout, flag= s) } } } - -#[global_allocator] -static ALLOCATOR: Kmalloc =3D Kmalloc; - -// See . -#[no_mangle] -static __rust_no_alloc_shim_is_unstable: u8 =3D 0; diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 8f423a1faf50..68c605049b87 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -247,18 +247,13 @@ $(obj)/%.lst: $(obj)/%.c FORCE =20 # Compile Rust sources (.rs) # ------------------------------------------------------------------------= --- - -rust_allowed_features :=3D new_uninit - # `--out-dir` is required to avoid temporaries being created by `rustc` in= the # current working directory, which may be not accessible in the out-of-tree # modules case. rust_common_cmd =3D \ RUST_MODFILE=3D$(modfile) $(RUSTC_OR_CLIPPY) $(rust_flags) \ - -Zallow-features=3D$(rust_allowed_features) \ -Zcrate-attr=3Dno_std \ - -Zcrate-attr=3D'feature($(rust_allowed_features))' \ - -Zunstable-options --extern force:alloc --extern kernel \ + -Zunstable-options --extern kernel \ --crate-type rlib -L $(objtree)/rust/ \ --crate-name $(basename $(notdir $@)) \ --sysroot=3D/dev/null \ diff --git a/scripts/generate_rust_analyzer.py b/scripts/generate_rust_anal= yzer.py index d2bc63cde8c6..09e1d166d8d2 100755 --- a/scripts/generate_rust_analyzer.py +++ b/scripts/generate_rust_analyzer.py @@ -64,13 +64,6 @@ def generate_crates(srctree, objtree, sysroot_src, exter= nal_src, cfgs): [], ) =20 - append_crate( - "alloc", - sysroot_src / "alloc" / "src" / "lib.rs", - ["core", "compiler_builtins"], - cfg=3Dcrates_cfgs.get("alloc", []), - ) - append_crate( "macros", srctree / "rust" / "macros" / "lib.rs", @@ -96,7 +89,7 @@ def generate_crates(srctree, objtree, sysroot_src, extern= al_src, cfgs): append_crate( "kernel", srctree / "rust" / "kernel" / "lib.rs", - ["core", "alloc", "macros", "build_error", "bindings"], + ["core", "macros", "build_error", "bindings"], cfg=3Dcfg, ) crates[-1]["source"] =3D { @@ -133,7 +126,7 @@ def generate_crates(srctree, objtree, sysroot_src, exte= rnal_src, cfgs): append_crate( name, path, - ["core", "alloc", "kernel"], + ["core", "kernel"], cfg=3Dcfg, ) =20 --=20 2.46.1