kunit: irq: Continue increasing hrtimer interval for longer

Browse source

Currently, kunit_irq_test_timer_func() stops increasing the hrtimer
interval as soon as some forward progress is made in each of softirq and
task context.  Update it to use a more aggressive strategy: increase the
interval as long as the hrtimer is running significantly faster than
either context.

This resolves an occasional hang in the CRC and crypto library tests
under qemu-system-s390x.  It was exposed by the change in the default
preemption model on s390 from NONE to LAZY.  That seems to have exposed
the issue by allowing some forward progress to be made while the actual
system timer tick is still starved, preventing jiffies from increasing
or the task context from making much progress towards max_iterations.

Fixes: 201ceb94aa ("kunit: irq: Ensure timer doesn't fire too frequently")
Cc: stable@vger.kernel.org
Reviewed-by: David Gow <david@davidgow.net>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://patch.msgid.link/20260803181842.44648-1-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@kernel.org>

...

This commit is contained in:

Eric Biggers 2026-08-03 11:18:41 -07:00

parent b09bd2d92e

commit faa6c4c4e4

1 changed files with 6 additions and 4 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

10

include/kunit/run-in-irq-context.h

View file