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Diffstat (limited to 'vendor/rustix/src/process/membarrier.rs')
-rw-r--r-- | vendor/rustix/src/process/membarrier.rs | 92 |
1 files changed, 92 insertions, 0 deletions
diff --git a/vendor/rustix/src/process/membarrier.rs b/vendor/rustix/src/process/membarrier.rs new file mode 100644 index 0000000..26be07d --- /dev/null +++ b/vendor/rustix/src/process/membarrier.rs @@ -0,0 +1,92 @@ +//! The Linux `membarrier` syscall. + +use crate::process::Cpuid; +use crate::{backend, io}; + +pub use backend::process::types::MembarrierCommand; + +#[cfg(linux_kernel)] +bitflags::bitflags! { + /// A result from [`membarrier_query`]. + /// + /// These flags correspond to values of [`MembarrierCommand`] which are + /// supported in the OS. + #[repr(transparent)] + #[derive(Copy, Clone, Eq, PartialEq, Hash, Debug)] + pub struct MembarrierQuery: u32 { + /// `MEMBARRIER_CMD_GLOBAL` (also known as `MEMBARRIER_CMD_SHARED`) + #[doc(alias = "SHARED")] + #[doc(alias = "MEMBARRIER_CMD_SHARED")] + const GLOBAL = MembarrierCommand::Global as _; + /// `MEMBARRIER_CMD_GLOBAL_EXPEDITED` + const GLOBAL_EXPEDITED = MembarrierCommand::GlobalExpedited as _; + /// `MEMBARRIER_CMD_REGISTER_GLOBAL_EXPEDITED` + const REGISTER_GLOBAL_EXPEDITED = MembarrierCommand::RegisterGlobalExpedited as _; + /// `MEMBARRIER_CMD_PRIVATE_EXPEDITED` + const PRIVATE_EXPEDITED = MembarrierCommand::PrivateExpedited as _; + /// `MEMBARRIER_CMD_REGISTER_PRIVATE_EXPEDITED` + const REGISTER_PRIVATE_EXPEDITED = MembarrierCommand::RegisterPrivateExpedited as _; + /// `MEMBARRIER_CMD_PRIVATE_EXPEDITED_SYNC_CORE` + const PRIVATE_EXPEDITED_SYNC_CORE = MembarrierCommand::PrivateExpeditedSyncCore as _; + /// `MEMBARRIER_CMD_REGISTER_PRIVATE_EXPEDITED_SYNC_CORE` + const REGISTER_PRIVATE_EXPEDITED_SYNC_CORE = MembarrierCommand::RegisterPrivateExpeditedSyncCore as _; + /// `MEMBARRIER_CMD_PRIVATE_EXPEDITED_RSEQ` (since Linux 5.10) + const PRIVATE_EXPEDITED_RSEQ = MembarrierCommand::PrivateExpeditedRseq as _; + /// `MEMBARRIER_CMD_REGISTER_PRIVATE_EXPEDITED_RSEQ` (since Linux 5.10) + const REGISTER_PRIVATE_EXPEDITED_RSEQ = MembarrierCommand::RegisterPrivateExpeditedRseq as _; + + /// <https://docs.rs/bitflags/*/bitflags/#externally-defined-flags> + const _ = !0; + } +} + +#[cfg(linux_kernel)] +impl MembarrierQuery { + /// Test whether this query result contains the given command. + #[inline] + pub fn contains_command(self, cmd: MembarrierCommand) -> bool { + // `MembarrierCommand` is an enum that only contains values also valid + // in `MembarrierQuery`. + self.contains(Self::from_bits_retain(cmd as _)) + } +} + +/// `membarrier(MEMBARRIER_CMD_QUERY, 0, 0)`—Query the supported `membarrier` +/// commands. +/// +/// This function doesn't return a `Result` because it always succeeds; if the +/// underlying OS doesn't support the `membarrier` syscall, it returns an empty +/// `MembarrierQuery` value. +/// +/// # References +/// - [Linux] +/// +/// [Linux]: https://man7.org/linux/man-pages/man2/membarrier.2.html +#[inline] +#[doc(alias = "MEMBARRIER_CMD_QUERY")] +pub fn membarrier_query() -> MembarrierQuery { + backend::process::syscalls::membarrier_query() +} + +/// `membarrier(cmd, 0, 0)`—Perform a memory barrier. +/// +/// # References +/// - [Linux] +/// +/// [Linux]: https://man7.org/linux/man-pages/man2/membarrier.2.html +#[inline] +pub fn membarrier(cmd: MembarrierCommand) -> io::Result<()> { + backend::process::syscalls::membarrier(cmd) +} + +/// `membarrier(cmd, MEMBARRIER_CMD_FLAG_CPU, cpu)`—Perform a memory barrier +/// with a specific CPU. +/// +/// # References +/// - [Linux] +/// +/// [Linux]: https://man7.org/linux/man-pages/man2/membarrier.2.html +#[inline] +pub fn membarrier_cpu(cmd: MembarrierCommand, cpu: Cpuid) -> io::Result<()> { + backend::process::syscalls::membarrier_cpu(cmd, cpu) +} |