ethtool: add CRC32 as an RSS hash function

CRC32 engines are usually easily available in hardware and generate
OK spread for RSS hash.  Add CRC32 RSS hash function to ethtool API.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h
index 9ded8c6d8176b909cf68da0e125eef4441b7c9a9..83cc9863444b078765255b9010b015578768be09 100644 (file)
--- a/include/linux/ethtool.h
+++ b/include/linux/ethtool.h
@@ -60,6 +60,7 @@ enum ethtool_phys_id_state {
 enum {
        ETH_RSS_HASH_TOP_BIT, /* Configurable RSS hash function - Toeplitz */
        ETH_RSS_HASH_XOR_BIT, /* Configurable RSS hash function - Xor */
+       ETH_RSS_HASH_CRC32_BIT, /* Configurable RSS hash function - Crc32 */
 
        /*
         * Add your fresh new hash function bits above and remember to update
@@ -73,6 +74,7 @@ enum {
 
 #define ETH_RSS_HASH_TOP       __ETH_RSS_HASH(TOP)
 #define ETH_RSS_HASH_XOR       __ETH_RSS_HASH(XOR)
+#define ETH_RSS_HASH_CRC32     __ETH_RSS_HASH(CRC32)
 
 #define ETH_RSS_HASH_UNKNOWN   0
 #define ETH_RSS_HASH_NO_CHANGE 0

diff --git a/net/core/ethtool.c b/net/core/ethtool.c
index aecb2c7241b697e79628fdb79467f5087b2bbf9f..905a88ad28e096d57289eba7f966629336382032 100644 (file)
--- a/net/core/ethtool.c
+++ b/net/core/ethtool.c
@@ -109,6 +109,7 @@ static const char
 rss_hash_func_strings[ETH_RSS_HASH_FUNCS_COUNT][ETH_GSTRING_LEN] = {
        [ETH_RSS_HASH_TOP_BIT] =        "toeplitz",
        [ETH_RSS_HASH_XOR_BIT] =        "xor",
+       [ETH_RSS_HASH_CRC32_BIT] =      "crc32",
 };
 
 static const char