From: =?UTF-8?q?Bj=C3=B6rn=20T=C3=B6pel?= <bjorn.topel@intel.com>
Date: Thu, 19 Dec 2019 07:10:05 +0100
Subject: xdp: Remove map_to_flush and map swap detection
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Patch-mainline: v5.6-rc1
Git-commit: 332f22a60e4c3492d4953cd6f7aaa4e8bd0bba97
References: bsc#1177028
Now that all XDP maps that can be used with bpf_redirect_map() tracks
entries to be flushed in a global fashion, there is not need to track
that the map has changed and flush from xdp_do_generic_map()
anymore. All entries will be flushed in xdp_do_flush_map().
This means that the map_to_flush can be removed, and the corresponding
checks. Moving the flush logic to one place, xdp_do_flush_map(), give
a bulking behavior and performance boost.
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20191219061006.21980-8-bjorn.topel@gmail.com
Acked-by: Gary Lin <glin@suse.com>
---
include/linux/filter.h | 1 -
net/core/filter.c | 27 +++------------------------
2 files changed, 3 insertions(+), 25 deletions(-)
--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -592,7 +592,6 @@ struct bpf_redirect_info {
u32 tgt_index;
void *tgt_value;
struct bpf_map *map;
- struct bpf_map *map_to_flush;
u32 kern_flags;
};
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -3549,26 +3549,9 @@ static int __bpf_tx_xdp_map(struct net_d
void xdp_do_flush_map(void)
{
- struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
- struct bpf_map *map = ri->map_to_flush;
-
- ri->map_to_flush = NULL;
- if (map) {
- switch (map->map_type) {
- case BPF_MAP_TYPE_DEVMAP:
- case BPF_MAP_TYPE_DEVMAP_HASH:
- __dev_map_flush();
- break;
- case BPF_MAP_TYPE_CPUMAP:
- __cpu_map_flush();
- break;
- case BPF_MAP_TYPE_XSKMAP:
- __xsk_map_flush();
- break;
- default:
- break;
- }
- }
+ __dev_map_flush();
+ __cpu_map_flush();
+ __xsk_map_flush();
}
EXPORT_SYMBOL_GPL(xdp_do_flush_map);
@@ -3617,14 +3600,10 @@ static int xdp_do_redirect_map(struct ne
ri->tgt_value = NULL;
WRITE_ONCE(ri->map, NULL);
- if (ri->map_to_flush && unlikely(ri->map_to_flush != map))
- xdp_do_flush_map();
-
err = __bpf_tx_xdp_map(dev, fwd, map, xdp);
if (unlikely(err))
goto err;
- ri->map_to_flush = map;
_trace_xdp_redirect_map(dev, xdp_prog, fwd, map, index);
return 0;
err: