lpm/arm: support SVE

Added new path to do lpm4 lookup by using scalable vector extension.
The SVE path will be selected if compiler has flag SVE set.

Signed-off-by: Ruifeng Wang <ruifeng.wang@arm.com>
Acked-by: Vladimir Medvedkin <vladimir.medvedkin@intel.com>

diff --git a/lib/librte_eal/arm/include/rte_vect.h b/lib/librte_eal/arm/include/rte_vect.h
index a739e6e..093e912 100644 (file)
--- a/lib/librte_eal/arm/include/rte_vect.h
+++ b/lib/librte_eal/arm/include/rte_vect.h
@@ -9,6 +9,9 @@
 #include "generic/rte_vect.h"
 #include "rte_debug.h"
 #include "arm_neon.h"
+#ifdef __ARM_FEATURE_SVE
+#include <arm_sve.h>
+#endif
 
 #ifdef __cplusplus
 extern "C" {

diff --git a/lib/librte_lpm/meson.build b/lib/librte_lpm/meson.build
index 6cfc083..f93c866 100644 (file)
--- a/lib/librte_lpm/meson.build
+++ b/lib/librte_lpm/meson.build
@@ -5,6 +5,6 @@ sources = files('rte_lpm.c', 'rte_lpm6.c')
 headers = files('rte_lpm.h', 'rte_lpm6.h')
 # since header files have different names, we can install all vector headers
 # without worrying about which architecture we actually need
-headers += files('rte_lpm_altivec.h', 'rte_lpm_neon.h', 'rte_lpm_sse.h')
+headers += files('rte_lpm_altivec.h', 'rte_lpm_neon.h', 'rte_lpm_sse.h', 'rte_lpm_sve.h')
 deps += ['hash']
 deps += ['rcu']

diff --git a/lib/librte_lpm/rte_lpm.h b/lib/librte_lpm/rte_lpm.h
index 1afe55c..28b5768 100644 (file)
--- a/lib/librte_lpm/rte_lpm.h
+++ b/lib/librte_lpm/rte_lpm.h
@@ -402,7 +402,11 @@ rte_lpm_lookupx4(const struct rte_lpm *lpm, xmm_t ip, uint32_t hop[4],
        uint32_t defv);
 
 #if defined(RTE_ARCH_ARM)
+#ifdef __ARM_FEATURE_SVE
+#include "rte_lpm_sve.h"
+#else
 #include "rte_lpm_neon.h"
+#endif
 #elif defined(RTE_ARCH_PPC_64)
 #include "rte_lpm_altivec.h"
 #else

diff --git a/lib/librte_lpm/rte_lpm_sve.h b/lib/librte_lpm/rte_lpm_sve.h
new file mode 100644 (file)
index 0000000..2e31937
--- /dev/null
+++ b/lib/librte_lpm/rte_lpm_sve.h
@@ -0,0 +1,83 @@
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright(c) 2020 Arm Limited
+ */
+
+#ifndef _RTE_LPM_SVE_H_
+#define _RTE_LPM_SVE_H_
+
+#include <rte_vect.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+__rte_internal
+static void
+__rte_lpm_lookup_vec(const struct rte_lpm *lpm, const uint32_t *ips,
+               uint32_t *__rte_restrict next_hops, const uint32_t n)
+{
+       uint32_t i = 0;
+       svuint32_t v_ip, v_idx, v_tbl24, v_tbl8, v_hop;
+       svuint32_t v_mask_xv, v_mask_v, v_mask_hop;
+       svbool_t pg = svwhilelt_b32(i, n);
+       svbool_t pv;
+
+       do {
+               v_ip = svld1(pg, &ips[i]);
+               /* Get indices for tbl24[] */
+               v_idx = svlsr_x(pg, v_ip, 8);
+               /* Extract values from tbl24[] */
+               v_tbl24 = svld1_gather_index(pg, (const uint32_t *)lpm->tbl24,
+                                               v_idx);
+
+               /* Create mask with valid set */
+               v_mask_v = svdup_u32_z(pg, RTE_LPM_LOOKUP_SUCCESS);
+               /* Create mask with valid and valid_group set */
+               v_mask_xv = svdup_u32_z(pg, RTE_LPM_VALID_EXT_ENTRY_BITMASK);
+               /* Create predicate for tbl24 entries: (valid && !valid_group) */
+               pv = svcmpeq(pg, svand_z(pg, v_tbl24, v_mask_xv), v_mask_v);
+               /* Create mask for next_hop in table entry */
+               v_mask_hop = svdup_u32_z(pg, 0x00ffffff);
+               /* Extract next_hop and write back */
+               v_hop = svand_x(pv, v_tbl24, v_mask_hop);
+               svst1(pv, &next_hops[i], v_hop);
+
+               /* Update predicate for tbl24 entries: (valid && valid_group) */
+               pv = svcmpeq(pg, svand_z(pg, v_tbl24, v_mask_xv), v_mask_xv);
+               /* Compute tbl8 index */
+               v_idx = svand_x(pv, v_tbl24, svdup_u32_z(pv, 0xffffff));
+               v_idx = svmul_x(pv, v_idx, RTE_LPM_TBL8_GROUP_NUM_ENTRIES);
+               v_idx = svadd_x(pv, svand_x(pv, v_ip, svdup_u32_z(pv, 0xff)),
+                               v_idx);
+               /* Extract values from tbl8[] */
+               v_tbl8 = svld1_gather_index(pv, (const uint32_t *)lpm->tbl8,
+                                               v_idx);
+               /* Update predicate for tbl8 entries: (valid) */
+               pv = svcmpeq(pv, svand_z(pv, v_tbl8, v_mask_v), v_mask_v);
+               /* Extract next_hop and write back */
+               v_hop = svand_x(pv, v_tbl8, v_mask_hop);
+               svst1(pv, &next_hops[i], v_hop);
+
+               i += svlen(v_ip);
+               pg = svwhilelt_b32(i, n);
+       } while (svptest_any(svptrue_b32(), pg));
+}
+
+static inline void
+rte_lpm_lookupx4(const struct rte_lpm *lpm, xmm_t ip, uint32_t hop[4],
+               uint32_t defv)
+{
+       uint32_t i, ips[4];
+
+       vst1q_s32((int32_t *)ips, ip);
+       for (i = 0; i < 4; i++)
+               hop[i] = defv;
+
+       __rte_lpm_lookup_vec(lpm, ips, hop, 4);
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _RTE_LPM_SVE_H_ */