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LorrensP-2158466LorrensP-2158466
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Implement FreeBSD syscall cpuset_getaffinity.
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3 files changed

+117
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‎src/tools/miri/ci/ci.sh‎

Lines changed: 2 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -165,8 +165,8 @@ case $HOST_TARGET in
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# Partially supported targets (tier 2)
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BASIC="empty_main integer heap_alloc libc-mem vec string btreemap" # ensures we have the basics: pre-main code, system allocator
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UNIX="hello panic/panic panic/unwind concurrency/simple atomic libc-mem libc-misc libc-random env num_cpus" # the things that are very similar across all Unixes, and hence easily supported there
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TEST_TARGET=x86_64-unknown-freebsd run_tests_minimal $BASIC $UNIX time hashmap random thread sync concurrency fs libc-pipe
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TEST_TARGET=i686-unknown-freebsd run_tests_minimal $BASIC $UNIX time hashmap random thread sync concurrency fs libc-pipe
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TEST_TARGET=x86_64-unknown-freebsd run_tests_minimal $BASIC $UNIX time hashmap random thread sync concurrency fs libc-pipe affinity
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TEST_TARGET=i686-unknown-freebsd run_tests_minimal $BASIC $UNIX time hashmap random thread sync concurrency fs libc-pipe affinity
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TEST_TARGET=aarch64-linux-android run_tests_minimal $BASIC $UNIX time hashmap random thread sync concurrency epoll eventfd
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TEST_TARGET=wasm32-wasip2 run_tests_minimal $BASIC wasm
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TEST_TARGET=wasm32-unknown-unknown run_tests_minimal no_std empty_main wasm # this target doesn't really have std

‎src/tools/miri/src/shims/unix/freebsd/foreign_items.rs‎

Lines changed: 64 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -56,6 +56,70 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
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this.write_scalar(res, dest)?;
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}
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"cpuset_getaffinity" => {
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// The "same" kind of api as `sched_getaffinity` but more fine grained control for FreeBSD specifically.
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let [level, which, id, set_size, mask] =
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this.check_shim(abi, Conv::C, link_name, args)?;
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let level = this.read_scalar(level)?.to_i32()?;
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let which = this.read_scalar(which)?.to_i32()?;
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let id = this.read_scalar(id)?.to_i64()?;
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let set_size = this.read_target_usize(set_size)?; // measured in bytes
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let mask = this.read_pointer(mask)?;
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let _level_root = this.eval_libc_i32("CPU_LEVEL_ROOT");
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let _level_cpuset = this.eval_libc_i32("CPU_LEVEL_CPUSET");
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let level_which = this.eval_libc_i32("CPU_LEVEL_WHICH");
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let _which_tid = this.eval_libc_i32("CPU_WHICH_TID");
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let which_pid = this.eval_libc_i32("CPU_WHICH_PID");
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let _which_jail = this.eval_libc_i32("CPU_WHICH_JAIL");
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let _which_cpuset = this.eval_libc_i32("CPU_WHICH_CPUSET");
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let _which_irq = this.eval_libc_i32("CPU_WHICH_IRQ");
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// For sched_getaffinity, the current process is identified by -1.
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// TODO: Use gettid? I'm (LorrensP-2158466) not that familiar with this api .
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let id = match id {
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-1 => this.active_thread(),
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_ =>
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throw_unsup_format!(
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"`cpuset_getaffinity` is only supported with a pid of -1 (indicating the current thread)"
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),
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};
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if this.ptr_is_null(mask)? {
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this.set_last_error_and_return(LibcError("EFAULT"), dest)?;
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}
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// We only support CPU_LEVEL_WHICH and CPU_WHICH_PID for now.
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// This is the bare minimum to make the tests pass.
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else if level != level_which || which != which_pid {
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throw_unsup_format!(
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"`cpuset_getaffinity` is only supported with `level` set to CPU_LEVEL_WHICH and `which` set to CPU_WHICH_PID."
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);
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} else if let Some(cpuset) = this.machine.thread_cpu_affinity.get(&id) {
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// `cpusetsize` must be large enough to contain the entire CPU mask.
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// FreeBSD only uses `cpusetsize` to verify that it's sufficient for the kernel's CPU mask.
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// If it's too small, the syscall returns ERANGE.
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// If it's large enough, copying the kernel mask to user space is safe, regardless of the actual size.
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// See https://github.com/freebsd/freebsd-src/blob/909aa6781340f8c0b4ae01c6366bf1556ee2d1be/sys/kern/kern_cpuset.c#L1985
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if set_size < u64::from(this.machine.num_cpus).div_ceil(8) {
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this.set_last_error_and_return(LibcError("ERANGE"), dest)?;
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} else {
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let cpuset = cpuset.clone();
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let byte_count =
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Ord::min(cpuset.as_slice().len(), set_size.try_into().unwrap());
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this.write_bytes_ptr(
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mask,
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cpuset.as_slice()[..byte_count].iter().copied(),
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)?;
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this.write_null(dest)?;
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}
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} else {
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// `id` is always that of the active thread, so this is currently unreachable.
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unreachable!();
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}
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}
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59123
// Synchronization primitives
60124
"_umtx_op" => {
61125
let [obj, op, val, uaddr, uaddr2] =

‎src/tools/miri/tests/pass-dep/shims/freebsd-cpuset-affinity.rs‎

Lines changed: 51 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,51 @@
1+
//@only-target: freebsd
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//@compile-flags: -Zmiri-num-cpus=256
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use std::mem;
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fn getaffinity() {
7+
let mut set: libc::cpuset_t = unsafe { mem::zeroed() };
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unsafe {
9+
if libc::cpuset_getaffinity(
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libc::CPU_LEVEL_WHICH,
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libc::CPU_WHICH_PID,
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-1,
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size_of::<libc::cpuset_t>(),
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&mut set,
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) == 0
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{
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assert!(libc::CPU_COUNT(&set) == 256);
18+
}
19+
}
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}
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22+
fn get_small_cpu_mask() {
23+
let mut set: libc::cpuset_t = unsafe { core::mem::MaybeUninit::zeroed().assume_init() };
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// 256 CPUs so we need 32 bytes to represent this mask.
26+
// According to Freebsd only when `cpusetsize` is smaller than this value, does it return with ERANGE
27+
28+
let err = unsafe {
29+
libc::cpuset_getaffinity(libc::CPU_LEVEL_WHICH, libc::CPU_WHICH_PID, -1, 32, &mut set)
30+
};
31+
assert_eq!(err, 0, "Success Expected");
32+
33+
// 31 is not enough, so it should fail.
34+
let err = unsafe {
35+
libc::cpuset_getaffinity(libc::CPU_LEVEL_WHICH, libc::CPU_WHICH_PID, -1, 31, &mut set)
36+
};
37+
assert_eq!(err, -1, "Expected Failure");
38+
assert_eq!(std::io::Error::last_os_error().raw_os_error().unwrap(), libc::ERANGE);
39+
40+
// Zero should fail as well.
41+
let err = unsafe {
42+
libc::cpuset_getaffinity(libc::CPU_LEVEL_WHICH, libc::CPU_WHICH_PID, -1, 0, &mut set)
43+
};
44+
assert_eq!(err, -1, "Expected Failure");
45+
assert_eq!(std::io::Error::last_os_error().raw_os_error().unwrap(), libc::ERANGE);
46+
}
47+
48+
fn main() {
49+
getaffinity();
50+
get_small_cpu_mask();
51+
}

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