diff options
| author | Jesper Dangaard Brouer <brouer@redhat.com> | 2019-12-27 18:13:24 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2020-01-02 15:37:52 -0800 |
| commit | f13fc10785bc04f83fe0d7730beb8ff4be563a20 (patch) | |
| tree | 9284b79bba0aa682bb0019f1165a5fb50c6edace | |
| parent | 44768decb7c0a6c7c01995dbacc864f3921b6dac (diff) | |
page_pool: help compiler remove code in case CONFIG_NUMA=n
When kernel is compiled without NUMA support, then page_pool NUMA
config setting (pool->p.nid) doesn't make any practical sense. The
compiler cannot see that it can remove the code paths.
This patch avoids reading pool->p.nid setting in case of !CONFIG_NUMA,
in allocation and numa check code, which helps compiler to see the
optimisation potential. It leaves update code intact to keep API the
same.
$ ./scripts/bloat-o-meter net/core/page_pool.o-numa-enabled \
net/core/page_pool.o-numa-disabled
add/remove: 0/0 grow/shrink: 0/3 up/down: 0/-113 (-113)
Function old new delta
page_pool_create 401 398 -3
__page_pool_alloc_pages_slow 439 426 -13
page_pool_refill_alloc_cache 425 328 -97
Total: Before=3611, After=3498, chg -3.13%
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/core/page_pool.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/net/core/page_pool.c b/net/core/page_pool.c index 515bfb97fda1..9b7cbe35df37 100644 --- a/net/core/page_pool.c +++ b/net/core/page_pool.c @@ -113,7 +113,12 @@ static struct page *page_pool_refill_alloc_cache(struct page_pool *pool, /* Softirq guarantee CPU and thus NUMA node is stable. This, * assumes CPU refilling driver RX-ring will also run RX-NAPI. */ +#ifdef CONFIG_NUMA pref_nid = (pool->p.nid == NUMA_NO_NODE) ? numa_mem_id() : pool->p.nid; +#else + /* Ignore pool->p.nid setting if !CONFIG_NUMA, helps compiler */ + pref_nid = numa_mem_id(); /* will be zero like page_to_nid() */ +#endif /* Slower-path: Get pages from locked ring queue */ spin_lock(&r->consumer_lock); @@ -200,7 +205,11 @@ static struct page *__page_pool_alloc_pages_slow(struct page_pool *pool, */ /* Cache was empty, do real allocation */ +#ifdef CONFIG_NUMA page = alloc_pages_node(pool->p.nid, gfp, pool->p.order); +#else + page = alloc_pages(gfp, pool->p.order); +#endif if (!page) return NULL; |