add support of available_parallelism for target hermit

stlankes · stlankes · commit 48148b1bd142 · 2023-06-11T14:51:02.000+02:00
On RustyHermit, the function `get_processor_count` returns the
number of activated processors.
diff --git a/library/std/src/sys/hermit/thread.rs b/library/std/src/sys/hermit/thread.rs
@@ -1,6 +1,5 @@
 #![allow(dead_code)]
 
-use super::unsupported;
 use crate::ffi::CStr;
 use crate::io;
 use crate::mem;
@@ -99,7 +98,7 @@ impl Thread {
 }
 
 pub fn available_parallelism() -> io::Result<NonZeroUsize> {
-    unsupported()
+    unsafe { Ok(NonZeroUsize::new_unchecked(abi::get_processor_count())) }
 }
 
 pub mod guard {

Original file line number	Diff line number	Diff line change
`@@ -1,6 +1,5 @@`
`1`	`1`	`#![allow(dead_code)]`
`2`	`2`
`3`		`-use super::unsupported;`
`4`	`3`	`use crate::ffi::CStr;`
`5`	`4`	`use crate::io;`
`6`	`5`	`use crate::mem;`
`@@ -99,7 +98,7 @@ impl Thread {`
`99`	`98`	`}`
`100`	`99`
`101`	`100`	`pub fn available_parallelism() -> io::Result<NonZeroUsize> {`
`102`		`- unsupported()`
	`101`	`+ unsafe { Ok(NonZeroUsize::new_unchecked(abi::get_processor_count())) }`
`103`	`102`	`}`
`104`	`103`
`105`	`104`	`pub mod guard {`