[dpdk-dev] [PATCH 1/7] net/sfc/base: add a new means to control RSS hash

[Andrew Rybchenko <arybchenko@solarflare.com>]

From: Ivan Malov <ivan.malov@oktetlabs.ru>

Currently, libefx has no support for additional RSS modes
available with later controllers. In order to support this,
libefx should be able to list available hash configurations.

This patch provides basic infrastructure for the new interface.
The client drivers will be able to query the list of supported
hash configurations for a particular hash algorithm. Also, it
will be possible to configure hashing by means of new definitions.

Signed-off-by: Ivan Malov <ivan.malov@oktetlabs.ru>
Signed-off-by: Andrew Rybchenko <arybchenko@solarflare.com>
---
 drivers/net/sfc/base/ef10_rx.c |  29 ++++++++--
 drivers/net/sfc/base/efx.h     |  90 +++++++++++++++++++++++++++++
 drivers/net/sfc/base/efx_rx.c  | 126 +++++++++++++++++++++++++++++++++++++++--
 3 files changed, 236 insertions(+), 9 deletions(-)

diff --git a/drivers/net/sfc/base/ef10_rx.c b/drivers/net/sfc/base/ef10_rx.c
index 86a6ac7..e7dd1ea 100644
--- a/drivers/net/sfc/base/ef10_rx.c
+++ b/drivers/net/sfc/base/ef10_rx.c
@@ -298,11 +298,32 @@ efx_mcdi_rss_context_set_flags(
 	__in		uint32_t rss_context,
 	__in		efx_rx_hash_type_t type)
 {
+	efx_rx_hash_type_t type_ipv4 = EFX_RX_HASH(IPV4, 2TUPLE);
+	efx_rx_hash_type_t type_ipv4_tcp = EFX_RX_HASH(IPV4_TCP, 4TUPLE);
+	efx_rx_hash_type_t type_ipv6 = EFX_RX_HASH(IPV6, 2TUPLE);
+	efx_rx_hash_type_t type_ipv6_tcp = EFX_RX_HASH(IPV6_TCP, 4TUPLE);
 	efx_mcdi_req_t req;
 	uint8_t payload[MAX(MC_CMD_RSS_CONTEXT_SET_FLAGS_IN_LEN,
 			    MC_CMD_RSS_CONTEXT_SET_FLAGS_OUT_LEN)];
 	efx_rc_t rc;
 
+	EFX_STATIC_ASSERT(EFX_RX_CLASS_IPV4_TCP_LBN ==
+		    MC_CMD_RSS_CONTEXT_SET_FLAGS_IN_TCP_IPV4_RSS_MODE_LBN);
+	EFX_STATIC_ASSERT(EFX_RX_CLASS_IPV4_TCP_WIDTH ==
+		    MC_CMD_RSS_CONTEXT_SET_FLAGS_IN_TCP_IPV4_RSS_MODE_WIDTH);
+	EFX_STATIC_ASSERT(EFX_RX_CLASS_IPV4_LBN ==
+		    MC_CMD_RSS_CONTEXT_SET_FLAGS_IN_OTHER_IPV4_RSS_MODE_LBN);
+	EFX_STATIC_ASSERT(EFX_RX_CLASS_IPV4_WIDTH ==
+		    MC_CMD_RSS_CONTEXT_SET_FLAGS_IN_OTHER_IPV4_RSS_MODE_WIDTH);
+	EFX_STATIC_ASSERT(EFX_RX_CLASS_IPV6_TCP_LBN ==
+		    MC_CMD_RSS_CONTEXT_SET_FLAGS_IN_TCP_IPV6_RSS_MODE_LBN);
+	EFX_STATIC_ASSERT(EFX_RX_CLASS_IPV6_TCP_WIDTH ==
+		    MC_CMD_RSS_CONTEXT_SET_FLAGS_IN_TCP_IPV6_RSS_MODE_WIDTH);
+	EFX_STATIC_ASSERT(EFX_RX_CLASS_IPV6_LBN ==
+		    MC_CMD_RSS_CONTEXT_SET_FLAGS_IN_OTHER_IPV6_RSS_MODE_LBN);
+	EFX_STATIC_ASSERT(EFX_RX_CLASS_IPV6_WIDTH ==
+		    MC_CMD_RSS_CONTEXT_SET_FLAGS_IN_OTHER_IPV6_RSS_MODE_WIDTH);
+
 	if (rss_context == EF10_RSS_CONTEXT_INVALID) {
 		rc = EINVAL;
 		goto fail1;
@@ -320,13 +341,13 @@ efx_mcdi_rss_context_set_flags(
 
 	MCDI_IN_POPULATE_DWORD_4(req, RSS_CONTEXT_SET_FLAGS_IN_FLAGS,
 	    RSS_CONTEXT_SET_FLAGS_IN_TOEPLITZ_IPV4_EN,
-	    (type & EFX_RX_HASH_IPV4) ? 1 : 0,
+	    ((type & type_ipv4) == type_ipv4) ? 1 : 0,
 	    RSS_CONTEXT_SET_FLAGS_IN_TOEPLITZ_TCPV4_EN,
-	    (type & EFX_RX_HASH_TCPIPV4) ? 1 : 0,
+	    ((type & type_ipv4_tcp) == type_ipv4_tcp) ? 1 : 0,
 	    RSS_CONTEXT_SET_FLAGS_IN_TOEPLITZ_IPV6_EN,
-	    (type & EFX_RX_HASH_IPV6) ? 1 : 0,
+	    ((type & type_ipv6) == type_ipv6) ? 1 : 0,
 	    RSS_CONTEXT_SET_FLAGS_IN_TOEPLITZ_TCPV6_EN,
-	    (type & EFX_RX_HASH_TCPIPV6) ? 1 : 0);
+	    ((type & type_ipv6_tcp) == type_ipv6_tcp) ? 1 : 0);
 
 	efx_mcdi_execute(enp, &req);
 
diff --git a/drivers/net/sfc/base/efx.h b/drivers/net/sfc/base/efx.h
index fd9f059..2b2b09f 100644
--- a/drivers/net/sfc/base/efx.h
+++ b/drivers/net/sfc/base/efx.h
@@ -2068,11 +2068,30 @@ typedef enum efx_rx_hash_alg_e {
 	EFX_RX_HASHALG_TOEPLITZ
 } efx_rx_hash_alg_t;
 
+/*
+ * Legacy hash type flags.
+ *
+ * They represent standard tuples for distinct traffic classes.
+ */
 #define	EFX_RX_HASH_IPV4	(1U << 0)
 #define	EFX_RX_HASH_TCPIPV4	(1U << 1)
 #define	EFX_RX_HASH_IPV6	(1U << 2)
 #define	EFX_RX_HASH_TCPIPV6	(1U << 3)
 
+#define	EFX_RX_HASH_LEGACY_MASK		\
+	(EFX_RX_HASH_IPV4	|	\
+	EFX_RX_HASH_TCPIPV4	|	\
+	EFX_RX_HASH_IPV6	|	\
+	EFX_RX_HASH_TCPIPV6)
+
+/*
+ * The type of the argument used by efx_rx_scale_mode_set() to
+ * provide a means for the client drivers to configure hashing.
+ *
+ * A properly constructed value can either be:
+ *  - a combination of legacy flags
+ *  - a combination of EFX_RX_HASH() flags
+ */
 typedef unsigned int efx_rx_hash_type_t;
 
 typedef enum efx_rx_hash_support_e {
@@ -2091,6 +2110,77 @@ typedef enum efx_rx_scale_context_type_e {
 	EFX_RX_SCALE_SHARED		/* Read-only key/indirection table */
 } efx_rx_scale_context_type_t;
 
+/*
+ * Traffic classes eligible for hash computation.
+ *
+ * Select packet headers used in computing the receive hash.
+ * This uses the same encoding as the RSS_MODES field of
+ * MC_CMD_RSS_CONTEXT_SET_FLAGS.
+ */
+#define	EFX_RX_CLASS_IPV4_TCP_LBN	8
+#define	EFX_RX_CLASS_IPV4_TCP_WIDTH	4
+#define	EFX_RX_CLASS_IPV4_LBN		16
+#define	EFX_RX_CLASS_IPV4_WIDTH		4
+#define	EFX_RX_CLASS_IPV6_TCP_LBN	20
+#define	EFX_RX_CLASS_IPV6_TCP_WIDTH	4
+#define	EFX_RX_CLASS_IPV6_LBN		28
+#define	EFX_RX_CLASS_IPV6_WIDTH		4
+
+#define	EFX_RX_NCLASSES			4
+
+/*
+ * Ancillary flags used to construct generic hash tuples.
+ * This uses the same encoding as RSS_MODE_HASH_SELECTOR.
+ */
+#define	EFX_RX_CLASS_HASH_SRC_ADDR	(1U << 0)
+#define	EFX_RX_CLASS_HASH_DST_ADDR	(1U << 1)
+#define	EFX_RX_CLASS_HASH_SRC_PORT	(1U << 2)
+#define	EFX_RX_CLASS_HASH_DST_PORT	(1U << 3)
+
+/*
+ * Generic hash tuples.
+ *
+ * They express combinations of packet fields
+ * which can contribute to the hash value for
+ * a particular traffic class.
+ */
+#define	EFX_RX_CLASS_HASH_DISABLE	0
+
+#define	EFX_RX_CLASS_HASH_2TUPLE		\
+	(EFX_RX_CLASS_HASH_SRC_ADDR	|	\
+	EFX_RX_CLASS_HASH_DST_ADDR)
+
+#define	EFX_RX_CLASS_HASH_4TUPLE		\
+	(EFX_RX_CLASS_HASH_SRC_ADDR	|	\
+	EFX_RX_CLASS_HASH_DST_ADDR	|	\
+	EFX_RX_CLASS_HASH_SRC_PORT	|	\
+	EFX_RX_CLASS_HASH_DST_PORT)
+
+#define EFX_RX_CLASS_HASH_NTUPLES	3
+
+/*
+ * Hash flag constructor.
+ *
+ * Resulting flags encode hash tuples for specific traffic classes.
+ * The client drivers are encouraged to use these flags to form
+ * a hash type value.
+ */
+#define	EFX_RX_HASH(_class, _tuple)				\
+	EFX_INSERT_FIELD_NATIVE32(0, 31,			\
+	EFX_RX_CLASS_##_class, EFX_RX_CLASS_HASH_##_tuple)
+
+/*
+ * The maximum number of EFX_RX_HASH() flags.
+ */
+#define	EFX_RX_HASH_NFLAGS	(EFX_RX_NCLASSES * EFX_RX_CLASS_HASH_NTUPLES)
+
+extern	__checkReturn				efx_rc_t
+efx_rx_scale_hash_flags_get(
+	__in					efx_nic_t *enp,
+	__in					efx_rx_hash_alg_t hash_alg,
+	__inout_ecount(EFX_RX_HASH_NFLAGS)	unsigned int *flags,
+	__out					unsigned int *nflagsp);
+
 extern	__checkReturn	efx_rc_t
 efx_rx_hash_default_support_get(
 	__in		efx_nic_t *enp,
diff --git a/drivers/net/sfc/base/efx_rx.c b/drivers/net/sfc/base/efx_rx.c
index ae79584..b495c74 100644
--- a/drivers/net/sfc/base/efx_rx.c
+++ b/drivers/net/sfc/base/efx_rx.c
@@ -294,6 +294,61 @@ efx_rx_scatter_enable(
 #endif	/* EFSYS_OPT_RX_SCATTER */
 
 #if EFSYS_OPT_RX_SCALE
+	__checkReturn				efx_rc_t
+efx_rx_scale_hash_flags_get(
+	__in					efx_nic_t *enp,
+	__in					efx_rx_hash_alg_t hash_alg,
+	__inout_ecount(EFX_RX_HASH_NFLAGS)	unsigned int *flags,
+	__out					unsigned int *nflagsp)
+{
+	unsigned int *entryp = flags;
+	efx_rc_t rc;
+
+	if (flags == NULL || nflagsp == NULL) {
+		rc = EINVAL;
+		goto fail1;
+	}
+
+#define	LIST_FLAGS(_entryp, _class, _l4_hashing)			\
+	do {								\
+		if (_l4_hashing)					\
+			*(_entryp++) = EFX_RX_HASH(_class, 4TUPLE);	\
+									\
+		*(_entryp++) = EFX_RX_HASH(_class, 2TUPLE);		\
+		*(_entryp++) = EFX_RX_HASH(_class, DISABLE);		\
+									\
+		_NOTE(CONSTANTCONDITION)				\
+	} while (B_FALSE)
+
+	switch (hash_alg) {
+	case EFX_RX_HASHALG_TOEPLITZ:
+		LIST_FLAGS(entryp, IPV4_TCP, B_TRUE);
+		LIST_FLAGS(entryp, IPV6_TCP, B_TRUE);
+		LIST_FLAGS(entryp, IPV4, B_FALSE);
+		LIST_FLAGS(entryp, IPV6, B_FALSE);
+		break;
+
+	default:
+		rc = EINVAL;
+		goto fail2;
+	}
+
+#undef LIST_FLAGS
+
+	*nflagsp = (unsigned int)(entryp - flags);
+	EFSYS_ASSERT3U(*nflagsp, <=, EFX_RX_HASH_NFLAGS);
+
+	return (0);
+
+fail2:
+	EFSYS_PROBE(fail2);
+
+fail1:
+	EFSYS_PROBE1(fail1, efx_rc_t, rc);
+
+	return (rc);
+}
+
 	__checkReturn	efx_rc_t
 efx_rx_hash_default_support_get(
 	__in		efx_nic_t *enp,
@@ -425,19 +480,76 @@ efx_rx_scale_mode_set(
 	__in		boolean_t insert)
 {
 	const efx_rx_ops_t *erxop = enp->en_erxop;
+	unsigned int type_flags[EFX_RX_HASH_NFLAGS];
+	unsigned int type_nflags;
+	efx_rx_hash_type_t type_check;
+	unsigned int i;
 	efx_rc_t rc;
 
 	EFSYS_ASSERT3U(enp->en_magic, ==, EFX_NIC_MAGIC);
 	EFSYS_ASSERT3U(enp->en_mod_flags, &, EFX_MOD_RX);
 
+	/*
+	 * Legacy flags and modern bits cannot be
+	 * used at the same time in the hash type.
+	 */
+	if ((type & EFX_RX_HASH_LEGACY_MASK) &&
+	    (type & ~EFX_RX_HASH_LEGACY_MASK)) {
+		rc = EINVAL;
+		goto fail1;
+	}
+
+	/*
+	 * Translate legacy flags to the new representation
+	 * so that chip-specific handlers will consider the
+	 * new flags only.
+	 */
+	if (type & EFX_RX_HASH_IPV4)
+		type |= EFX_RX_HASH(IPV4, 2TUPLE);
+
+	if (type & EFX_RX_HASH_TCPIPV4)
+		type |= EFX_RX_HASH(IPV4_TCP, 4TUPLE);
+
+	if (type & EFX_RX_HASH_IPV6)
+		type |= EFX_RX_HASH(IPV6, 2TUPLE);
+
+	if (type & EFX_RX_HASH_TCPIPV6)
+		type |= EFX_RX_HASH(IPV6_TCP, 4TUPLE);
+
+	type &= ~EFX_RX_HASH_LEGACY_MASK;
+	type_check = type;
+
+	/*
+	 * Get the list of supported hash flags and sanitise the input.
+	 */
+	rc = efx_rx_scale_hash_flags_get(enp, alg, type_flags, &type_nflags);
+	if (rc != 0)
+		goto fail2;
+
+	for (i = 0; i < type_nflags; ++i) {
+		if ((type_check & type_flags[i]) == type_flags[i])
+			type_check &= ~(type_flags[i]);
+	}
+
+	if (type_check != 0) {
+		rc = EINVAL;
+		goto fail3;
+	}
+
 	if (erxop->erxo_scale_mode_set != NULL) {
 		if ((rc = erxop->erxo_scale_mode_set(enp, rss_context, alg,
 			    type, insert)) != 0)
-			goto fail1;
+			goto fail4;
 	}
 
 	return (0);
 
+fail4:
+	EFSYS_PROBE(fail4);
+fail3:
+	EFSYS_PROBE(fail3);
+fail2:
+	EFSYS_PROBE(fail2);
 fail1:
 	EFSYS_PROBE1(fail1, efx_rc_t, rc);
 	return (rc);
@@ -881,6 +993,10 @@ siena_rx_scale_mode_set(
 	__in		efx_rx_hash_type_t type,
 	__in		boolean_t insert)
 {
+	efx_rx_hash_type_t type_ipv4 = EFX_RX_HASH(IPV4, 2TUPLE);
+	efx_rx_hash_type_t type_ipv4_tcp = EFX_RX_HASH(IPV4_TCP, 4TUPLE);
+	efx_rx_hash_type_t type_ipv6 = EFX_RX_HASH(IPV6, 2TUPLE);
+	efx_rx_hash_type_t type_ipv6_tcp = EFX_RX_HASH(IPV6_TCP, 4TUPLE);
 	efx_rc_t rc;
 
 	if (rss_context != EFX_RSS_CONTEXT_DEFAULT) {
@@ -895,12 +1011,12 @@ siena_rx_scale_mode_set(
 
 	case EFX_RX_HASHALG_TOEPLITZ:
 		EFX_RX_TOEPLITZ_IPV4_HASH(enp, insert,
-		    type & EFX_RX_HASH_IPV4,
-		    type & EFX_RX_HASH_TCPIPV4);
+		    (type & type_ipv4) == type_ipv4,
+		    (type & type_ipv4_tcp) == type_ipv4_tcp);
 
 		EFX_RX_TOEPLITZ_IPV6_HASH(enp,
-		    type & EFX_RX_HASH_IPV6,
-		    type & EFX_RX_HASH_TCPIPV6,
+		    (type & type_ipv6) == type_ipv6,
+		    (type & type_ipv6_tcp) == type_ipv6_tcp,
 		    rc);
 		if (rc != 0)
 			goto fail2;
-- 
2.7.4