CVS commit: src

["Taylor R Campbell" <riastradh%netbsd.org@localhost>]

Module Name:    src
Committed By:   riastradh
Date:           Sun Dec 22 23:25:15 UTC 2024

Modified Files:
        src/distrib/sets/lists/debug: mi
        src/distrib/sets/lists/tests: mi
        src/tests/kernel: Makefile
Added Files:
        src/tests/kernel: t_time_arith.c

Log Message:
t_time_arith: New test for timer calculations.

This will facilitate fixing various problems in the arithmetic to
determine, given an itimer's scheduled time (it_value) and periodic
interval (it_interval) along with the current time of actual expiry
(now), what time the itimer should be rescheduled for (next, new
value of it_timer) on the same clock.

Later we can also put tests for other functions like tvtohz here, and
make them test many different values of hz/tick.

XXX Not 100% sure about all of these cases -- there is some room for
reasonable discussion about what the right answer is.  But we have
unquestionably implemented the wrong thing for many of these cases,
even if the answers this test checks for may not be quite right yet.

PR kern/58922: itimer(9): arithmetic overflow
PR kern/58925: itimer(9) responds erratically to clock wound back
PR kern/58926: itimer(9) integer overflow in overrun counting
PR kern/58927: itimer(9): overrun accounting is broken


To generate a diff of this commit:
cvs rdiff -u -r1.456 -r1.457 src/distrib/sets/lists/debug/mi
cvs rdiff -u -r1.1351 -r1.1352 src/distrib/sets/lists/tests/mi
cvs rdiff -u -r1.83 -r1.84 src/tests/kernel/Makefile
cvs rdiff -u -r0 -r1.1 src/tests/kernel/t_time_arith.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.