On 2021/6/27 14:09, Michael S. Tsirkin wrote: > On Fri, Jun 25, 2021 at 11:52:16AM +0800, Yunsheng Lin wrote: >> On 2021/6/25 11:36, Jason Wang wrote: >>> >>> 在 2021/6/25 上午11:18, Yunsheng Lin 写道: >>>> Currently ptr_ring selftest is embedded within the virtio >>>> selftest, which involves some specific virtio operation, >>>> such as notifying and kicking. >>>> >>>> As ptr_ring has been used by various subsystems, it deserves >>>> it's owner's selftest in order to benchmark different usecase >>>> of ptr_ring, such as page pool and pfifo_fast qdisc. >>>> >>>> So add a simple application to benchmark ptr_ring performance. >>>> Currently two test mode is supported: >>>> Mode 0: Both enqueuing and dequeuing is done in a single thread, >>>> it is called simple test mode in the test app. >>>> Mode 1: Enqueuing and dequeuing is done in different thread >>>> concurrently, also known as SPSC(single-producer/ >>>> single-consumer) test. >>>> >>>> The multi-producer/single-consumer test for pfifo_fast case is >>>> not added yet, which can be added if using CAS atomic operation >>>> to enable lockless multi-producer is proved to be better than >>>> using r->producer_lock. >>>> >>>> Only supported on x86 and arm64 for now. >>>> >>>> Signed-off-by: Yunsheng Lin <linyunsheng@xxxxxxxxxx> >>>> --- >>>> MAINTAINERS | 5 + >>>> tools/testing/selftests/ptr_ring/Makefile | 6 + >>>> tools/testing/selftests/ptr_ring/ptr_ring_test.c | 249 +++++++++++++++++++++++ >>>> tools/testing/selftests/ptr_ring/ptr_ring_test.h | 150 ++++++++++++++ >>>> 4 files changed, 410 insertions(+) >>> >>> >>> Why can't you simply reuse tools/virtio/ringtest? >> >> The main reason is stated in the commit log: >> "Currently ptr_ring selftest is embedded within the virtio >> selftest, which involves some specific virtio operation, >> such as notifying and kicking. >> >> As ptr_ring has been used by various subsystems, it deserves >> it's owner's selftest in order to benchmark different usecase >> of ptr_ring, such as page pool and pfifo_fast qdisc." >> >> More specificly in tools/virtio/ringtest/main.c and >> tools/virtio/ringtest/ptr_ring.c, there are a lot of operation >> related to virtio usecase, such as start_guest(), start_host(), >> poll_used(), notify() or kick() ....., so it makes more sense >> to add a generic selftest for ptr ring as it is not only used >> by virtio now. > > > Okay that answers why you didn't just run main.c > but why not add a new test under tools/virtio/ringtest/ > reusing the rest of infrastructure that you currently copied? Actually, my first attempt was to reuse the infrastructure in tools/virtio/ or tools/virtio/ringtest/, and neither of them was able to be compiled in the latest kernel. And then I read through the code to try fixing the compile error, I found that the testcase under tools/virtio/ is coupled deeply to virtio as explained above, which was difficult to read for someone who is not fimiliar with virtio. So I searched for how testing is supposed to be added in the kernel, it seems it is more common to add the testing in tools/testing or tools/testing/selftest, and ptr ring is not only used by virtio now, so it seems more appropriate to add a sperate testing for virtio by instinct. Most of tools/virtio/ is to do testing related to virtio testing, IMHO, most of them are better to be in tools/testing/selftest. Even if most of virtio testing is moved to tools/testing/selftest, I think it makes more sense to decouple the virtio testing to ptr_ring testing too if we can find some mechanism to share the abstract infrastructure in ptr_ring_test.h for both virtio and ptr_ring testing. > >> >>> >>> Thanks >>> >>> >>> . >>> > > > . >
