sched/numa: Trace decisions related to skipping VMAs

[ Upstream commit ed2da8b7 ]

NUMA balancing skips or scans VMAs for a variety of reasons. In preparation
for completing scans of VMAs regardless of PID access, trace the reasons
why a VMA was skipped. In a later patch, the tracing will be used to track
if a VMA was forcibly scanned.

Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20231010083143.19593-4-mgorman@techsingularity.net


Stable-dep-of: f22cde43 ("sched/numa: Fix the vma scan starving issue")
Signed-off-by: Sasha Levin <sashal@kernel.org>