ctmap: right-shift kernel jiffies by BPF_MONO_SCALER #26197
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Commit 8531c5a ("bpf,datapath: read jiffies from /proc/schedstat") switched package ctmap over to using /proc/schedstat for getting kernel jiffies. During the conversion, a shift by a magic 'scaler' value was missed, leading to strange output in `cilium bpf ct list global -d` (.. (remaining: -4391264792 sec(s)) ..) and the CT GC never collecting any flows, since the current jiffies were always perceived to be orders of magnitude larger than the flow expiry time. This patch wraps probes.Jiffies() in a documented scaledJiffies() helper and declares the BPF_MONO_SCALER macro as a Go constant. Signed-off-by: Timo Beckers <timo@isovalent.com>
ti-mo
added
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/test |
borkmann
approved these changes
Jun 13, 2023
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ci-external-workloads: looks like a transient infra issue. restarting. |
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ci-e2e: lots of one.one.one.one failures. not sure if re-trying would help, but let's see. |
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yeah let's ignore the one.one.one.one failures. it's not related to this pull request, and as you said it's happening in other pull requests too (#26160 (comment) is one example). i'll wait for |
michi-covalent
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This was referenced Jun 13, 2023
michi-covalent
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michi-covalent
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Commit 8531c5a ("bpf,datapath: read jiffies from /proc/schedstat") switched package ctmap over to using /proc/schedstat for getting kernel jiffies.
During the conversion, a shift by a magic 'scaler' value was missed, leading to strange output in
cilium bpf ct list global -d(.. (remaining: -4391264792 sec(s)) ..) and the CT GC never collecting any flows, since the current jiffies were always perceived to be orders of magnitude larger than the flow expiry time.This patch wraps probes.Jiffies() in a documented scaledJiffies() helper and declares the BPF_MONO_SCALER macro as a Go constant.
Fixes: #26182
Follow-up to: #25795