Re: [PATCH 1/3] KVM: selftests: Add unit to dirty_log_test

[Sean Christopherson <seanjc@google.com>]

On Mon, May 11, 2026, wu.fei9@sanechips.com.cn wrote:
> Currently dirty_log_test hardcodes usleep 1ms in each interval, which
> could be too short for guest to write and fault in enough pages, then
> there is less chance to test the write protection mechanism, especially
> in the case of (log_mode != LOG_MODE_DIRTY_RING).

But when log_mode != LOG_MODE_DIRTY_RING, the individual sleep time is largely
meaningless, because the test won't reap the bitmaps for iterations > 0.

			if (i && host_log_mode != LOG_MODE_DIRTY_RING)
				continue;

>
> Unit is introduced to replace the default 1ms if specified in command
> line. The following test can't trigger failure on my riscv vm:

Failure of what?  And does the failure really not reproduce with a higher interval?

> 
>   # ./dirty_log_test -m 21 -M clear-log
> 
> By enlarging unit, it fails every time:

"unit" is way too vague.   Even looking at the code, it's not clear to me what
you intended a "unit" to be.  I'm not entirely opposed to providing the user with
more control over the innards of the test, but the interface needs to be somewhat
intuitive.