page_pool: Add function to batch and return stats

Adds a function page_pool_get_stats which can be used by drivers to obtain
stats for a specified page_pool.

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>

diff --git a/include/net/page_pool.h b/include/net/page_pool.h
index 298af95..ea5fb70 100644 (file)
--- a/include/net/page_pool.h
+++ b/include/net/page_pool.h
@@ -107,6 +107,23 @@ struct page_pool_recycle_stats {
                              * refcnt
                              */
 };
+
+/* This struct wraps the above stats structs so users of the
+ * page_pool_get_stats API can pass a single argument when requesting the
+ * stats for the page pool.
+ */
+struct page_pool_stats {
+       struct page_pool_alloc_stats alloc_stats;
+       struct page_pool_recycle_stats recycle_stats;
+};
+
+/*
+ * Drivers that wish to harvest page pool stats and report them to users
+ * (perhaps via ethtool, debugfs, or another mechanism) can allocate a
+ * struct page_pool_stats call page_pool_get_stats to get stats for the specified pool.
+ */
+bool page_pool_get_stats(struct page_pool *pool,
+                        struct page_pool_stats *stats);
 #endif
 
 struct page_pool {

diff --git a/net/core/page_pool.c b/net/core/page_pool.c
index 3d273cb..1943c0f 100644 (file)
--- a/net/core/page_pool.c
+++ b/net/core/page_pool.c
@@ -35,6 +35,31 @@
                struct page_pool_recycle_stats __percpu *s = pool->recycle_stats;       \
                this_cpu_inc(s->__stat);                                                \
        } while (0)
+
+bool page_pool_get_stats(struct page_pool *pool,
+                        struct page_pool_stats *stats)
+{
+       int cpu = 0;
+
+       if (!stats)
+               return false;
+
+       memcpy(&stats->alloc_stats, &pool->alloc_stats, sizeof(pool->alloc_stats));
+
+       for_each_possible_cpu(cpu) {
+               const struct page_pool_recycle_stats *pcpu =
+                       per_cpu_ptr(pool->recycle_stats, cpu);
+
+               stats->recycle_stats.cached += pcpu->cached;
+               stats->recycle_stats.cache_full += pcpu->cache_full;
+               stats->recycle_stats.ring += pcpu->ring;
+               stats->recycle_stats.ring_full += pcpu->ring_full;
+               stats->recycle_stats.released_refcnt += pcpu->released_refcnt;
+       }
+
+       return true;
+}
+EXPORT_SYMBOL(page_pool_get_stats);
 #else
 #define alloc_stat_inc(pool, __stat)
 #define recycle_stat_inc(pool, __stat)