Add a Jiffy time unit with isize as its representation and provide
Delta<Jiffy>::from_jiffies() and as_jiffies() as the unit-specific
constructor and accessor, mirroring from_nanos()/as_nanos() on the
nanosecond Delta.
Represent the jiffies span as isize: Delta is a signed span (nanoseconds
use i64) and, as a timeout, the value only needs to reach
MAX_JIFFY_OFFSET ((LONG_MAX >> 1) - 1). isize is signed and matches the
kernel's c_long, so it meets both.
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Link: https://patch.msgid.link/20260808062839.1159990-3-tomo@flapping.org
[ Added intra-doc links. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2e0d41002a