Re: [PATCH] tests/plugin: Remove duplicate insn log from libinsn.so

[Richard Henderson <richard.henderson@linaro.org>]

On 6/11/23 02:14, Alex Bennée wrote:
> 
> Richard Henderson <richard.henderson@linaro.org> writes:
> 
>> This is a perfectly natural occurrence for x86 "rep movb",
>> where the "rep" prefix forms a counted loop of the one insn.
>>
>> During the tests/tcg/multiarch/memory test, this logging is
>> triggered over 350000 times.  Within the context of cross-i386-tci
>> build, which is already slow by nature, the logging is sufficient
>> to push the test into timeout.
> 
> How does this get triggered because I added these:
> 
> # non-inline runs will trigger the duplicate instruction heuristics in libinsn.so
> run-plugin-%-with-libinsn.so:
> 	$(call run-test, $@, \
> 	  $(QEMU) -monitor none -display none \
> 		  -chardev file$(COMMA)path=$@.out$(COMMA)id=output \
>                    -plugin ../../plugin/libinsn.so$(COMMA)inline=on \
> 	    	  -d plugin -D $*-with-libinsn.so.pout \
> 		  $(QEMU_OPTS) $*)
> 
> to prevent the callback versions from being called for x86. The original
> intent of the check was to detect failures due to cpu_io_recompile, see
> e025d799af (tests/plugin: expand insn test to detect duplicate instructions)

I have no idea how, but it's happening.


>> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
>> ---
>> Irritatingly, it doesn't timeout locally, so I used staging to double-check:
>>
>> Fail: https://gitlab.com/qemu-project/qemu/-/jobs/4450754282#L5062
>> Pass: https://gitlab.com/qemu-project/qemu/-/jobs/4450927108

Note that in the pass case, we don't even log that the test ran.


r~