Introduce max-cpu-num config item, remove all direct usages of axconfig::plat::CPU_NUM, use axplat to get cpu num. (arceos-org#317)

* squash from 28dc592 to 4f805fb

* update axplat_crates for arceos-helloworld-myplat

* fix errors after cherry-picking

* add `smp = {}` output for test purpose

* fix an out-dated comment

* move `init_cpu_num` into `init_later`

* cache `cpu_num` in select_run_queue_index

Author: aarkegz

Cargo.lock

@@ -3,7 +3,10 @@
 #     - `ARCH`: Target architecture: x86_64, riscv64, aarch64, loongarch64
 #     - `MYPLAT`: Package name of the target platform crate.
 #     - `PLAT_CONFIG`: Path to the platform configuration file.
-#     - `SMP`: Number of CPUs. If not set, use the default value from platform config.
+#     - `SMP`: Override maximum CPU number specified in the platform config. For
+#       statically configured platforms, this is also the number of CPUs to boot
+#       and for platforms with runtime CPU detection, this is the upper limit of
+#       CPUs.
 #     - `MODE`: Build mode: release, debug
 #     - `LOG:` Logging level: warn, error, info, debug, trace
 #     - `V`: Verbose level: (empty), 1, 2

Makefile

@@ -39,6 +39,11 @@ mod stdio {
     }
 }
 
+mod sys {
+    pub use axhal::cpu_num as ax_get_cpu_num;
+    pub use axhal::power::system_off as ax_terminate;
+}
+
 mod time {
     pub use axhal::time::{
         TimeValue as AxTimeValue, monotonic_time as ax_monotonic_time, wall_time as ax_wall_time,
@@ -47,8 +52,8 @@ mod time {
 
 pub use self::mem::*;
 pub use self::stdio::*;
+pub use self::sys::*;
 pub use self::task::*;
 pub use self::time::*;
 
-pub use axhal::power::system_off as ax_terminate;
 pub use axio::PollState as AxPollState;

api/arceos_api/src/imp/mod.rs

@@ -32,6 +32,9 @@ pub mod sys {
     define_api! {
         /// Shutdown the whole system and all CPUs.
         pub fn ax_terminate() -> !;
+
+        /// Returns the number of CPUs in the system.
+        pub fn ax_get_cpu_num() -> usize;
     }
 }
 

api/arceos_api/src/lib.rs

@@ -15,7 +15,7 @@ pub fn sys_sysconf(name: c_int) -> c_long {
             // Page size
             ctypes::_SC_PAGE_SIZE => Ok(PAGE_SIZE_4K),
             // Number of processors in use
-            ctypes::_SC_NPROCESSORS_ONLN => Ok(axconfig::plat::CPU_NUM),
+            ctypes::_SC_NPROCESSORS_ONLN => Ok(axhal::cpu_num()),
             // Total physical pages
             ctypes::_SC_PHYS_PAGES => Ok(axhal::mem::total_ram_size() / PAGE_SIZE_4K),
             // Avaliable physical pages

api/arceos_posix_api/src/imp/sys.rs

@@ -9,8 +9,9 @@ package = "axplat-x86-pc"       # str
 # Platform configs
 #
 [plat]
-# Number of CPUs.
-cpu-num = 8                     # uint
+# Maximum number of CPUs. For platforms that do not support runtime CPU number
+# detection, it's also the number of CPUs to boot (like this platform).
+max-cpu-num = 8                 # uint
 # Base address of the whole physical memory.
 phys-memory-base = 0            # uint
 # Size of the whole physical memory. (2G)

configs/custom/x86_64-pc-oslab.toml

@@ -15,8 +15,9 @@ ticks-per-sec = 100         # uint
 #
 [plat]
 # Platform family.
-# Number of CPUs
-cpu-num = 1                 # uint
+# Maximum number of CPUs. For platforms that do not support runtime CPU number
+# detection, it's also the number of CPUs to boot.
+max-cpu-num = 1             # uint
 # Base address of the whole physical memory.
 phys-memory-base = 0        # uint
 # Size of the whole physical memory.

configs/dummy.toml

@@ -18,16 +18,16 @@ cfg-if = "1.0"
 axstd = { workspace = true, features = ["myplat"], optional = true }
 
 [target.'cfg(target_arch = "x86_64")'.dependencies]
-axplat-x86-pc = { version = "0.2", features = ["smp", "irq"], optional = true }
+axplat-x86-pc = { version = "0.3", features = ["smp", "irq"], optional = true }
 
 [target.'cfg(target_arch = "aarch64")'.dependencies]
-axplat-aarch64-qemu-virt = { version = "0.2", features = ["smp", "irq"], optional = true }
-axplat-aarch64-raspi = { version = "0.2", features = ["smp", "irq"], optional = true }
-axplat-aarch64-bsta1000b = { version = "0.2", features = ["smp", "irq"], optional = true }
-axplat-aarch64-phytium-pi = { version = "0.2", features = ["smp", "irq"], optional = true }
+axplat-aarch64-qemu-virt = { version = "0.3", features = ["smp", "irq"], optional = true }
+axplat-aarch64-raspi = { version = "0.3", features = ["smp", "irq"], optional = true }
+axplat-aarch64-bsta1000b = { version = "0.3", features = ["smp", "irq"], optional = true }
+axplat-aarch64-phytium-pi = { version = "0.3", features = ["smp", "irq"], optional = true }
 
 [target.'cfg(target_arch = "riscv64")'.dependencies]
-axplat-riscv64-qemu-virt = { version = "0.2", features = ["smp", "irq"], optional = true }
+axplat-riscv64-qemu-virt = { version = "0.3", features = ["smp", "irq"], optional = true }
 
 [target.'cfg(target_arch = "loongarch64")'.dependencies]
-axplat-loongarch64-qemu-virt = { version = "0.2", features = ["smp", "irq"], optional = true }
+axplat-loongarch64-qemu-virt = { version = "0.3", features = ["smp", "irq"], optional = true }

examples/helloworld-myplat/Cargo.toml

@@ -36,23 +36,23 @@ memory_addr = "0.4"
 linkme = { version = "0.3.33", optional = true }
 page_table_multiarch = { version = "0.5", features = ["copy-from"], optional = true }
 axcpu = "0.2"
-axplat = "0.2"
+axplat = "0.3"
 axlog = { workspace = true }
 axconfig = { workspace = true }
 axalloc = { workspace = true, optional = true }
 
 [target.'cfg(target_arch = "x86_64")'.dependencies]
-axplat-x86-pc = { version = "0.2", optional = true }
+axplat-x86-pc = { version = "0.3", optional = true }
 
 [target.'cfg(target_arch = "aarch64")'.dependencies]
 aarch64-cpu = "10.0"
-axplat-aarch64-qemu-virt = { version = "0.2", optional = true }
+axplat-aarch64-qemu-virt = { version = "0.3", optional = true }
 
 [target.'cfg(target_arch = "riscv64")'.dependencies]
-axplat-riscv64-qemu-virt = { version = "0.2", optional = true }
+axplat-riscv64-qemu-virt = { version = "0.3", optional = true }
 
 [target.'cfg(target_arch = "loongarch64")'.dependencies]
-axplat-loongarch64-qemu-virt = { version = "0.2", optional = true }
+axplat-loongarch64-qemu-virt = { version = "0.3", optional = true }
 
 [build-dependencies]
 axconfig = { workspace = true }

modules/axhal/Cargo.toml

@@ -24,7 +24,7 @@ fn gen_linker_script(arch: &str, platform: &str) -> Result<()> {
         "%KERNEL_BASE%",
         &format!("{:#x}", axconfig::plat::KERNEL_BASE_VADDR),
     );
-    let ld_content = ld_content.replace("%CPU_NUM%", &format!("{}", axconfig::plat::CPU_NUM));
+    let ld_content = ld_content.replace("%CPU_NUM%", &format!("{}", axconfig::plat::MAX_CPU_NUM));
 
     // target/<target_triple>/<mode>/build/axhal-xxxx/out
     let out_dir = std::env::var("OUT_DIR").unwrap();