test2:complete alt_alloc!

Author: LHHL7

arceos/exercises/alt_alloc/src/main.rs

@@ -1,5 +1,6 @@
 #![cfg_attr(feature = "axstd", no_std)]
-#![cfg_attr(feature = "axstd", no_main)]
+//如果启用了 axstd 特性，那么应用 #![no_std] 属性" 即不使用rust 标准库
+#![cfg_attr(feature = "axstd", no_main)]//不使用标准main
 
 #[macro_use]
 #[cfg(feature = "axstd")]
@@ -8,7 +9,7 @@ extern crate alloc;
 
 use alloc::vec::Vec;
 
-#[cfg_attr(feature = "axstd", no_mangle)]
+#[cfg_attr(feature = "axstd", no_mangle)]//禁止rust名称修饰
 fn main() {
     println!("Running bump tests...");
 

arceos/modules/alt_axalloc/src/lib.rs

@@ -96,7 +96,7 @@ unsafe impl GlobalAlloc for GlobalAllocator {
         GlobalAllocator::dealloc(self, NonNull::new(ptr).expect("dealloc null ptr"), layout)
     }
 }
-
+//满足条件时作为全局分配器 all()代表同时满足  条件1 target_os = "none" 目标系统是裸机 条件2 not(test) 不是测试环境
 #[cfg_attr(all(target_os = "none", not(test)), global_allocator)]
 static GLOBAL_ALLOCATOR: GlobalAllocator = GlobalAllocator::new();
 

arceos/modules/bump_allocator/src/lib.rs

@@ -1,6 +1,11 @@
 #![no_std]
 
 use allocator::{BaseAllocator, ByteAllocator, PageAllocator};
+use core::ptr::NonNull;
+//这个allocator是外部库 在cargo.toml中有
+//它定义了这三个BaseAllocator, ByteAllocator, PageAllocator trait
+//我只要考虑具体实现它们就好
+
 
 /// Early memory allocator
 /// Use it before formal bytes-allocator and pages-allocator can work!
@@ -16,73 +21,115 @@ use allocator::{BaseAllocator, ByteAllocator, PageAllocator};
 /// When it goes down to ZERO, free bytes-used area.
 /// For pages area, it will never be freed!
 ///
-pub struct EarlyAllocator<const SIZE: usize> {}
+pub struct EarlyAllocator<const SIZE: usize> {
+    start:usize,//内存起始地址
+    b_pos:usize,
+    p_pos:usize,
+    end:usize,//内存结束地址
+    count:usize,//记录字节分配的次数 
+    //由于bump分配器不好归还分配区域 所以使用count来帮助
+}
 
-impl<const SIZE: usize> EarlyAllocator<SIZE> {
+impl<const SIZE: usize> EarlyAllocator<SIZE> {// 创建未初始化的分配器
     pub const fn new() -> Self {
-        Self {}
+        Self {
+            start:0,
+            b_pos:0,
+            p_pos:0,
+            end:0,
+            count:0,
+        }
     }
 }
 
 impl<const SIZE: usize> BaseAllocator for EarlyAllocator<SIZE> {
-    fn init(&mut self, start: usize, size: usize) {
-        todo!()
+    fn init(&mut self, start: usize, size: usize) {//真正的初始化 运行时设置内存区域
+        self.start=start;
+        self.b_pos=start;
+        self.p_pos=start+size;
+        self.end=start+size;
+        self.count=0;
     }
 
     fn add_memory(&mut self, start: usize, size: usize) -> allocator::AllocResult {
+        //扩展新的内存空间 但bump算法本身不好支持扩展
         todo!()
     }
 }
 
 impl<const SIZE: usize> ByteAllocator for EarlyAllocator<SIZE> {
     fn alloc(
         &mut self,
-        layout: core::alloc::Layout,
+        layout: core::alloc::Layout,//layout是rust标准库里定义的结构体 
+        //  两个成员size: usize, // 需要分配的字节数    align: usize,     // 内存对齐要求（必须是2的幂）
     ) -> allocator::AllocResult<core::ptr::NonNull<u8>> {
-        todo!()
+        //AllocResult<NonNull<u8>>  是Result<NonNull<u8>, AllocError>的别名
+        //成功返回一个nonnull非空指针 指向u8的   失败返回allocerror类型
+        let align=layout.align();
+        let size=layout.size();//两个量是私有的 通过方法访问
+        //分配的内存起始地址要是align的倍数
+        let aligned_addr = (self.b_pos + align - 1) & !(align - 1);//经典的对齐公式  !(align - 1) 创造了掩码 与之前结果按位与 将低位置零
+        self.b_pos+=size;
+        self.count+=1;
+        Ok(unsafe { NonNull::new_unchecked(aligned_addr as *mut u8) })
+
     }
 
     fn dealloc(&mut self, pos: core::ptr::NonNull<u8>, layout: core::alloc::Layout) {
-        todo!()
+        //当dealloc使得 count变0时 再释放字节分配区域
+        self.count-=1;
+        if self.count==0 {
+            // println!("[BUMP]重置字节区域 b_pos:{}--->{}",self.b_pos,self.start);
+            self.b_pos=self.start;
+        }
     }
 
-    fn total_bytes(&self) -> usize {
-        todo!()
+    fn total_bytes(&self) -> usize {//总内存大小
+        self.end-self.start
     }
 
-    fn used_bytes(&self) -> usize {
-        todo!()
+    fn used_bytes(&self) -> usize {//已使用字节
+        self.b_pos-self.start
     }
 
-    fn available_bytes(&self) -> usize {
-        todo!()
+    fn available_bytes(&self) -> usize {//可用字节  即还能分配多少字节
+        self.p_pos-self.b_pos
     }
 }
 
 impl<const SIZE: usize> PageAllocator for EarlyAllocator<SIZE> {
     const PAGE_SIZE: usize = SIZE;
-
+    //在 Rust 中，trait 里定义的常量是关联常量 需要通过类型来访问 Self::PAGE_SIZE
     fn alloc_pages(
         &mut self,
         num_pages: usize,
         align_pow2: usize,
+        //align_pow2 表示对齐值的2的幂指数，而不是对齐值本身
     ) -> allocator::AllocResult<usize> {
-        todo!()
+        // 使用 align_pow2 可以直接进行位运算
+        let align = 1 << align_pow2;  // 快速计算对齐值
+        //计算边界
+        let aligned_addr = (self.p_pos - align + 1) & !(align - 1);
+
+        //更新p_pos
+        self.p_pos=aligned_addr-num_pages*Self::PAGE_SIZE;
+
+        Ok(aligned_addr)
     }
 
-    fn dealloc_pages(&mut self, pos: usize, num_pages: usize) {
+    fn dealloc_pages(&mut self, pos: usize, num_pages: usize) {//页分配区域不会free
         todo!()
     }
 
     fn total_pages(&self) -> usize {
-        todo!()
+        (self.end-self.start)/Self::PAGE_SIZE
     }
 
     fn used_pages(&self) -> usize {
-        todo!()
+        (self.end-self.p_pos)/Self::PAGE_SIZE
     }
 
     fn available_pages(&self) -> usize {
-        todo!()
+        (self.p_pos-self.b_pos)/Self::PAGE_SIZE
     }
 }

arceos/rust-toolchain.toml

@@ -2,5 +2,8 @@
 profile = "minimal"
 # channel = "nightly-2024-05-02"
 channel = "nightly-2024-09-04"
+# channel = "nightly-2024-10-15"
+# channel = "nightly-2024-08-01"
+# channel = "nightly-2024-07-01"
 components = ["rust-src", "llvm-tools", "rustfmt", "clippy"]
 targets = ["x86_64-unknown-none", "riscv64gc-unknown-none-elf", "aarch64-unknown-none", "aarch64-unknown-none-softfloat"]

arceos/rustc-ice-2025-11-07T11_38_55-4115.txt

@@ -0,0 +1,50 @@
+thread 'rustc' panicked at compiler/rustc_metadata/src/rmeta/decoder/cstore_impl.rs:244:1:
+DefId(4:51 ~ allocator[45e5]::PageAllocator::PAGE_SIZE) does not have a "fn_arg_names"
+stack backtrace:
+   0:     0x7013c0262f25 - std::backtrace::Backtrace::create::hecd2f73b2ce7b07a
+   1:     0x7013be9c7695 - std::backtrace::Backtrace::force_capture::h170b9a096c05276d
+   2:     0x7013bdb43d47 - std[23d648ca06a6b5c2]::panicking::update_hook::<alloc[5896b17b70d00093]::boxed::Box<rustc_driver_impl[c6327b079c7bb00b]::install_ice_hook::{closure#0}>>::{closure#0}
+   3:     0x7013be9deab8 - std::panicking::rust_panic_with_hook::h0a4b940661a26423
+   4:     0x7013be9de887 - std::panicking::begin_panic_handler::{{closure}}::h72160a9fdca8fdc8
+   5:     0x7013be9dc4c9 - std::sys::backtrace::__rust_end_short_backtrace::hb6826ea75cd9c94b
+   6:     0x7013be9de554 - rust_begin_unwind
+   7:     0x7013bb898f63 - core::panicking::panic_fmt::h47b5abafd035aaaa
+   8:     0x7013be0a97c2 - rustc_metadata[e2ce326aece1cd9a]::rmeta::decoder::cstore_impl::provide_extern::fn_arg_names::{closure#2}
+   9:     0x7013be0a964e - rustc_metadata[e2ce326aece1cd9a]::rmeta::decoder::cstore_impl::provide_extern::fn_arg_names
+  10:     0x7013c0734fe9 - rustc_query_impl[a11ca8e41e94db86]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[a11ca8e41e94db86]::query_impl::fn_arg_names::dynamic_query::{closure#2}::{closure#0}, rustc_middle[d764cafae524af68]::query::erase::Erased<[u8; 16usize]>>.cold
+  11:     0x7013bf4a1055 - <rustc_query_impl[a11ca8e41e94db86]::query_impl::fn_arg_names::dynamic_query::{closure#2} as core[ad5a27a180104093]::ops::function::FnOnce<(rustc_middle[d764cafae524af68]::ty::context::TyCtxt, rustc_span[35307b2b70fcf344]::def_id::DefId)>>::call_once
+  12:     0x7013bf6173c1 - rustc_query_system[2ff07926b95779e9]::query::plumbing::try_execute_query::<rustc_query_impl[a11ca8e41e94db86]::DynamicConfig<rustc_query_system[2ff07926b95779e9]::query::caches::DefIdCache<rustc_middle[d764cafae524af68]::query::erase::Erased<[u8; 16usize]>>, false, false, false>, rustc_query_impl[a11ca8e41e94db86]::plumbing::QueryCtxt, false>
+  13:     0x7013bf616cae - rustc_query_impl[a11ca8e41e94db86]::query_impl::fn_arg_names::get_query_non_incr::__rust_end_short_backtrace
+  14:     0x7013bf615b23 - rustc_middle[d764cafae524af68]::query::plumbing::query_get_at::<rustc_query_system[2ff07926b95779e9]::query::caches::DefIdCache<rustc_middle[d764cafae524af68]::query::erase::Erased<[u8; 16usize]>>>
+  15:     0x7013be5e51a0 - <rustc_resolve[2e8d4a957ac066c6]::late::LateResolutionVisitor>::try_lookup_name_relaxed
+  16:     0x7013be5dd9d1 - <rustc_resolve[2e8d4a957ac066c6]::late::LateResolutionVisitor>::smart_resolve_report_errors
+  17:     0x7013bc10e47c - <rustc_resolve[2e8d4a957ac066c6]::late::LateResolutionVisitor>::smart_resolve_path_fragment::{closure#0}
+  18:     0x7013bfd6ead6 - <rustc_resolve[2e8d4a957ac066c6]::late::LateResolutionVisitor>::smart_resolve_path_fragment
+  19:     0x7013bfd5fab6 - <rustc_resolve[2e8d4a957ac066c6]::late::LateResolutionVisitor>::resolve_expr
+  20:     0x7013bfd60c94 - <rustc_resolve[2e8d4a957ac066c6]::late::LateResolutionVisitor>::resolve_expr
+  21:     0x7013bfd5f4d0 - <rustc_resolve[2e8d4a957ac066c6]::late::LateResolutionVisitor>::resolve_block
+  22:     0x7013bbb256d9 - <rustc_resolve[2e8d4a957ac066c6]::late::LateResolutionVisitor as rustc_ast[425c09b15625e00f]::visit::Visitor>::visit_fn
+  23:     0x7013bc1d22ef - <rustc_resolve[2e8d4a957ac066c6]::late::LateResolutionVisitor as rustc_ast[425c09b15625e00f]::visit::Visitor>::visit_item
+  24:     0x7013c0420f6f - <rustc_resolve[2e8d4a957ac066c6]::Resolver>::resolve_crate::{closure#0}
+  25:     0x7013c041b340 - <rustc_resolve[2e8d4a957ac066c6]::Resolver>::resolve_crate
+  26:     0x7013bf72723e - rustc_interface[1a90780ba77f0571]::passes::resolver_for_lowering_raw
+  27:     0x7013bf72646b - rustc_query_impl[a11ca8e41e94db86]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[a11ca8e41e94db86]::query_impl::resolver_for_lowering_raw::dynamic_query::{closure#2}::{closure#0}, rustc_middle[d764cafae524af68]::query::erase::Erased<[u8; 16usize]>>
+  28:     0x7013bf726459 - <rustc_query_impl[a11ca8e41e94db86]::query_impl::resolver_for_lowering_raw::dynamic_query::{closure#2} as core[ad5a27a180104093]::ops::function::FnOnce<(rustc_middle[d764cafae524af68]::ty::context::TyCtxt, ())>>::call_once
+  29:     0x7013c0173d12 - rustc_query_system[2ff07926b95779e9]::query::plumbing::try_execute_query::<rustc_query_impl[a11ca8e41e94db86]::DynamicConfig<rustc_query_system[2ff07926b95779e9]::query::caches::SingleCache<rustc_middle[d764cafae524af68]::query::erase::Erased<[u8; 16usize]>>, false, false, false>, rustc_query_impl[a11ca8e41e94db86]::plumbing::QueryCtxt, false>
+  30:     0x7013c01739ad - rustc_query_impl[a11ca8e41e94db86]::query_impl::resolver_for_lowering_raw::get_query_non_incr::__rust_end_short_backtrace
+  31:     0x7013bffc276e - rustc_interface[1a90780ba77f0571]::interface::run_compiler::<core[ad5a27a180104093]::result::Result<(), rustc_span[35307b2b70fcf344]::ErrorGuaranteed>, rustc_driver_impl[c6327b079c7bb00b]::run_compiler::{closure#0}>::{closure#1}
+  32:     0x7013c009aed0 - std[23d648ca06a6b5c2]::sys::backtrace::__rust_begin_short_backtrace::<rustc_interface[1a90780ba77f0571]::util::run_in_thread_with_globals<rustc_interface[1a90780ba77f0571]::util::run_in_thread_pool_with_globals<rustc_interface[1a90780ba77f0571]::interface::run_compiler<core[ad5a27a180104093]::result::Result<(), rustc_span[35307b2b70fcf344]::ErrorGuaranteed>, rustc_driver_impl[c6327b079c7bb00b]::run_compiler::{closure#0}>::{closure#1}, core[ad5a27a180104093]::result::Result<(), rustc_span[35307b2b70fcf344]::ErrorGuaranteed>>::{closure#0}, core[ad5a27a180104093]::result::Result<(), rustc_span[35307b2b70fcf344]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[ad5a27a180104093]::result::Result<(), rustc_span[35307b2b70fcf344]::ErrorGuaranteed>>
+  33:     0x7013c009b53a - <<std[23d648ca06a6b5c2]::thread::Builder>::spawn_unchecked_<rustc_interface[1a90780ba77f0571]::util::run_in_thread_with_globals<rustc_interface[1a90780ba77f0571]::util::run_in_thread_pool_with_globals<rustc_interface[1a90780ba77f0571]::interface::run_compiler<core[ad5a27a180104093]::result::Result<(), rustc_span[35307b2b70fcf344]::ErrorGuaranteed>, rustc_driver_impl[c6327b079c7bb00b]::run_compiler::{closure#0}>::{closure#1}, core[ad5a27a180104093]::result::Result<(), rustc_span[35307b2b70fcf344]::ErrorGuaranteed>>::{closure#0}, core[ad5a27a180104093]::result::Result<(), rustc_span[35307b2b70fcf344]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[ad5a27a180104093]::result::Result<(), rustc_span[35307b2b70fcf344]::ErrorGuaranteed>>::{closure#1} as core[ad5a27a180104093]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
+  34:     0x7013c009b92b - std::sys::pal::unix::thread::Thread::new::thread_start::h17951d08fc5208d5
+  35:     0x7013ba294ac3 - <unknown>
+  36:     0x7013ba3268c0 - <unknown>
+  37:                0x0 - <unknown>
+
+
+rustc version: 1.83.0-nightly (d6c8169c1 2024-09-03)
+platform: x86_64-unknown-linux-gnu
+
+query stack during panic:
+#0 [fn_arg_names] looking up function parameter names for `allocator::PageAllocator::PAGE_SIZE`
+#1 [resolver_for_lowering_raw] getting the resolver for lowering
+end of query stack