ynl: samples: fix recycling rate calculation

Running the page-pool sample on production machines under moderate
networking load shows recycling rate higher than 100%:

$ page-pool
    eth0[2]	page pools: 14 (zombies: 0)
		refs: 89088 bytes: 364904448 (refs: 0 bytes: 0)
		recycling: 100.3% (alloc: 1392:2290247724 recycle: 469289484:1828235386)

Note that outstanding refs (89088) == slow alloc * cache size (1392 * 64)
which means this machine is recycling page pool pages perfectly, not
a single page has been released.

The extra 0.3% is because sample ignores allocations from the ptr_ring.
Treat those the same as alloc_fast, the ring vs cache alloc is
already captured accurately enough by recycling stats.

With the fix:

$ page-pool
    eth0[2]	page pools: 14 (zombies: 0)
		refs: 89088 bytes: 364904448 (refs: 0 bytes: 0)
		recycling: 100.0% (alloc: 1392:2331141604 recycle: 473625579:1857460661)

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Jakub Kicinski 2024-03-07 14:11:22 -08:00 committed by David S. Miller
parent 08842c43d0
commit 900b2801bf

View File

@ -95,6 +95,8 @@ int main(int argc, char **argv)
if (pp->_present.alloc_fast)
s->alloc_fast += pp->alloc_fast;
if (pp->_present.alloc_refill)
s->alloc_fast += pp->alloc_refill;
if (pp->_present.alloc_slow)
s->alloc_slow += pp->alloc_slow;
if (pp->_present.recycle_ring)