From: "Juraj Linkeš" <juraj.linkes@pantheon.tech>
To: "dev@dpdk.org" <dev@dpdk.org>
Subject: [dpdk-dev] Minimun value of RTE_MAX_LCORE
Date: Thu, 15 Oct 2020 10:49:17 +0000 [thread overview]
Message-ID: <317a9b0f7130448190e2391150bd0f67@pantheon.tech> (raw)
Hi dpdk devs,
Is there a constraint on how low RTE_MAX_LCORE can be? I'm implementing a discovery mechanism that sets RTE_MAX_LCORE according to the number of host cores, but I'm hitting errors when the values are low:
https://travis-ci.com/github/jlinkes/dpdk/jobs/399596828
Message: Found 2
cores
Message: Found 1
numa nodes
../app/test/test_rcu_qsbr.c:296:54: error: iteration 2 invokes undefined behavior [-Werror=aggressive-loop-optimizations]
../app/test/test_rcu_qsbr.c:315:55: error: array subscript is above array bounds [-Werror=array-bounds]
All VM jobs failed in that Travis build. Travis VMs only have 2 cores, so I tried to put a bound on the build. I set it to 4 and all jobs except GCC shared lib jobs passed, which still threw iteration 4 invokes undefined behavior error:
https://travis-ci.com/github/jlinkes/dpdk/jobs/400004089
../examples/performance-thread/l3fwd-thread/main.c:2338:34: error: iteration 4 invokes undefined behavior [-Werror=aggressive-loop-optimizations]
This happens for number of cores < 32 and looks like a limitation unique to l3fwd (with cores between 4 and 32 - I didn't see the error elsewhere).
Should I use the bound or are these legitimate errors? The fact that only GCC (and not clang) shared lib jobs failed is also suspicious.
Thanks,
Juraj
next reply other threads:[~2020-10-15 10:49 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-10-15 10:49 Juraj Linkeš [this message]
2020-10-15 11:15 ` Bruce Richardson
2020-10-15 11:30 ` Gaëtan Rivet
2020-10-15 12:14 ` Juraj Linkeš
2020-10-16 6:06 ` Honnappa Nagarahalli
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