/proc/meminfo: add percpu populated pages count

Currently, percpu memory only exposes allocation and utilization
information via debugfs.  This more or less is only really useful for
understanding the fragmentation and allocation information at a per-chunk
level with a few global counters.  This is also gated behind a config.
BPF and cgroup, for example, have seen an increase in use causing
increased use of percpu memory.  Let's make it easier for someone to
identify how much memory is being used.

This patch adds the "Percpu" stat to meminfo to more easily look up how
much percpu memory is in use.  This number includes the cost for all
allocated backing pages and not just insight at the per a unit, per chunk
level.  Metadata is excluded.  I think excluding metadata is fair because
the backing memory scales with the numbere of cpus and can quickly
outweigh the metadata.  It also makes this calculation light.

Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Dennis Zhou <[email protected]>
Acked-by: Tejun Heo <[email protected]>
Acked-by: Roman Gushchin <[email protected]>
Reviewed-by: Andrew Morton <[email protected]>
Acked-by: David Rientjes <[email protected]>
Acked-by: Vlastimil Babka <[email protected]>
Cc: Johannes Weiner <[email protected]>
Cc: Christoph Lameter <[email protected]>
Cc: Alexey Dobriyan <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

0 files changed, 0 insertions, 0 deletions