page_pool: Add allocation stats

Add per-pool statistics counters for the allocation path of a page pool.
These stats are incremented in softirq context, so no locking or per-cpu
variables are needed.

This code is disabled by default and a kernel config option is provided for
users who wish to enable them.

The statistics added are:
	- fast: successful fast path allocations
	- slow: slow path order-0 allocations
	- slow_high_order: slow path high order allocations
	- empty: ptr ring is empty, so a slow path allocation was forced.
	- refill: an allocation which triggered a refill of the cache
	- waive: pages obtained from the ptr ring that cannot be added to
	  the cache due to a NUMA mismatch.

Signed-off-by: Joe Damato <jdamato@fastly.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Joe Damato
2022-03-01 23:55:47 -08:00
committed by David S. Miller
parent 42f0c1934c
commit 8610037e81
3 changed files with 51 additions and 4 deletions

View File

@@ -434,6 +434,19 @@ config NET_DEVLINK
config PAGE_POOL
bool
config PAGE_POOL_STATS
default n
bool "Page pool stats"
depends on PAGE_POOL
help
Enable page pool statistics to track page allocation and recycling
in page pools. This option incurs additional CPU cost in allocation
and recycle paths and additional memory cost to store the statistics.
These statistics are only available if this option is enabled and if
the driver using the page pool supports exporting this data.
If unsure, say N.
config FAILOVER
tristate "Generic failover module"
help