On 2024-11-19 09:35:51 [+0800], Hou Tao wrote: > Hi Sebastian, Hi Hou, > On 11/18/2024 11:39 PM, Sebastian Andrzej Siewior wrote: > > On 2024-11-18 09:07:58 [+0800], Hou Tao wrote: > >> From: Hou Tao <houtao1@xxxxxxxxxx> > >> > >> Hi, > > Hi, > > > >> Please see individual patches for more details. Comments are always > >> welcome. > > This might be a coincidence but it seems I get > > > > | helper_fill_hashmap(282):FAIL:can't update hashmap err: Unknown error -12 > > | test_maps: test_maps.c:1379: __run_parallel: Assertion `status == 0' failed. > > > > more often with the series when I do ./test_maps. I never managed to > > pass the test with series while it passed on v6.12. I'm not blaming the > > series, just pointing this out it might be known… > > Thanks for the information. 12 is ENOMEM, so the hash map failed to > allocate an element for it. There are multiple possible reasons for ENOMEM: > > 1) something is wrong for bpf mem allocator. E.g., it could not refill > the free list timely. It may be possible when running under RT, because > the irq work is threaded under RT. right. forgot to switch that one off. I had it for the initial test… > 2) the series causes the shortage of memory (e.g., It uses a lot memory > then free these memory, but the reclaim of the memory is slow) > Could you please share the kernel config file and the VM setup, so I > could try to reproduce the problem ? I very much thing this is due to the RT switch. The irq-work and testcase run on different CPUs so… > > In 08/10 you switch the locks to raw_spinlock_t. I was a little worried > > that a lot of elements will make the while() loop go for a long time. Is > > there a test for this? I run into "test_progs -a map_kptr" and noticed > > something else… > > The concern is the possibility of hard-lockup, right ? The total time Not lockup but spending a "visible amount of time" for the lookup. > used for update or deletion is decided by the max_prefixlen. The typical > use case will use 32 or 128 as the max_prefixlen. The max value of > max_prefixlen is LPM_DATA_SIZE_MAX * 8 = 2048, I think the loop time > will be fine. Will try to construct some test cases for it. Okay, thank you. Sebastian
