From 3a2197f5fe95894f4536b2c0382076d52812d15e Mon Sep 17 00:00:00 2001 From: Daniel Canter Date: Fri, 2 Sep 2022 20:31:35 -0700 Subject: [PATCH] metrics/cgroups/v1: Remove unused event parameter The event parameter wasn't actually used when processing oom events, likely because it's only ever available for reads. Additionally clarify flush is for eventfds, and point to where the buffer size of 8 is coming from. Signed-off-by: Daniel Canter --- metrics/cgroups/v1/oom.go | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/metrics/cgroups/v1/oom.go b/metrics/cgroups/v1/oom.go index a7fa2658a..2882e775b 100644 --- a/metrics/cgroups/v1/oom.go +++ b/metrics/cgroups/v1/oom.go @@ -121,14 +121,14 @@ func (o *oomCollector) start() { return } for i := 0; i < n; i++ { - o.process(uintptr(events[i].Fd), events[i].Events) + o.process(uintptr(events[i].Fd)) } } } -func (o *oomCollector) process(fd uintptr, event uint32) { - // make sure to always flush the fd - flush(fd) +func (o *oomCollector) process(fd uintptr) { + // make sure to always flush the eventfd + flushEventfd(fd) o.mu.Lock() info, ok := o.set[fd] @@ -152,8 +152,10 @@ func (o *oomCollector) process(fd uintptr, event uint32) { } } -func flush(fd uintptr) error { +func flushEventfd(efd uintptr) error { + // Buffer must be >= 8 bytes for eventfd reads + // https://man7.org/linux/man-pages/man2/eventfd.2.html var buf [8]byte - _, err := unix.Read(int(fd), buf[:]) + _, err := unix.Read(int(efd), buf[:]) return err }