Skip to content

The boot CPU waits for an AP's echo as long as a dead CPU is: 5 s, not 100 ms #670

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
Japabu merged 2 commits into from
Oct 1, 2026
Merged

The boot CPU waits for an AP's echo as long as a dead CPU is: 5 s, not 100 ms #670

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
3f70813
A wait on a guest reads the guest's own clock, and an AP is waited fo…
Japabu Oct 1, 2026
8b94f84
Review round 1: the guest clock and WIDTH's deletion go; AP_START stays
Japabu Oct 1, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
30 changes: 0 additions & 30 deletions issues/kernel/an-ap-its-host-has-not-scheduled-for-100-ms-is-booted-without.md
View file
Open in desktop

This file was deleted.

6 changes: 4 additions & 2 deletions kernel/src/time.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -242,9 +242,11 @@ impl fmt::Display for Budget {
}
}

/// How long the boot CPU waits for an AP it started to echo its token.
/// How long the boot CPU waits for an AP it started to echo its token:
/// [`DEAF_CPU`]'s span, because a vCPU its host has not run yet is slow and not
/// dead.
pub const AP_START: Budget = Budget::of(
Duration::from_millis(100),
Duration::from_nanos(DEAF_CPU.nanos()),
"the machine boots with the CPUs that came up before the first that did not",
);

Expand Down
Loading