From: Michal Mazurek <m...@semihalf.com>
Add an implementation of the rte_lpm_lookupx4() function for platforms
without support for vector operations.
Signed-off-by: Michal Mazurek <m...@semihalf.com>
Signed-off-by: Stanislaw Kardach <k...@semihalf.com>
Sponsored-by: Frank Zhao <frank.z...@starfivetech.com>
Sponsored-by: Sam Grove <sam.gr...@sifive.com>
---
doc/guides/rel_notes/release_22_07.rst | 5 +
lib/lpm/meson.build | 1 +
lib/lpm/rte_lpm.h | 4 +-
lib/lpm/rte_lpm_scalar.h | 122 +++++++++++++++++++++++++
4 files changed, 131 insertions(+), 1 deletion(-)
create mode 100644 lib/lpm/rte_lpm_scalar.h
diff --git a/doc/guides/rel_notes/release_22_07.rst
b/doc/guides/rel_notes/release_22_07.rst
index 88d6e96cc1..067118174b 100644
--- a/doc/guides/rel_notes/release_22_07.rst
+++ b/doc/guides/rel_notes/release_22_07.rst
@@ -65,6 +65,11 @@ New Features
* Added support for promiscuous mode on Windows.
* Added support for MTU on Windows.
+* **Added scalar version of the LPM library.**
+
+ * Added scalar implementation of ``rte_lpm_lookupx4``. This is a fall-back
+ implementation for platforms that don't support vector operations.
+
Removed Items
-------------
diff --git a/lib/lpm/meson.build b/lib/lpm/meson.build
index 78d91d3421..6b47361fce 100644
--- a/lib/lpm/meson.build
+++ b/lib/lpm/meson.build
@@ -14,6 +14,7 @@ headers = files('rte_lpm.h', 'rte_lpm6.h')
indirect_headers += files(
'rte_lpm_altivec.h',
'rte_lpm_neon.h',
+ 'rte_lpm_scalar.h',
'rte_lpm_sse.h',
'rte_lpm_sve.h',
)
diff --git a/lib/lpm/rte_lpm.h b/lib/lpm/rte_lpm.h
index eb91960e81..b5db6a353a 100644
--- a/lib/lpm/rte_lpm.h
+++ b/lib/lpm/rte_lpm.h
@@ -405,8 +405,10 @@ rte_lpm_lookupx4(const struct rte_lpm *lpm, xmm_t ip,
uint32_t hop[4],
#endif
#elif defined(RTE_ARCH_PPC_64)
#include "rte_lpm_altivec.h"
-#else
+#elif defined(RTE_ARCH_X86)
#include "rte_lpm_sse.h"
+#else
+#include "rte_lpm_scalar.h"
#endif
#ifdef __cplusplus
diff --git a/lib/lpm/rte_lpm_scalar.h b/lib/lpm/rte_lpm_scalar.h
new file mode 100644
index 0000000000..991b94e687
--- /dev/null
+++ b/lib/lpm/rte_lpm_scalar.h
@@ -0,0 +1,122 @@
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright(c) 2022 StarFive
+ * Copyright(c) 2022 SiFive
+ * Copyright(c) 2022 Semihalf
+ */
+
+#ifndef _RTE_LPM_SCALAR_H_
+#define _RTE_LPM_SCALAR_H_
+
+#include <rte_branch_prediction.h>
+#include <rte_byteorder.h>
+#include <rte_common.h>
+#include <rte_vect.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+static inline void
+rte_lpm_lookupx4(const struct rte_lpm *lpm, xmm_t ip, uint32_t hop[4],
+ uint32_t defv)
+{
+ rte_xmm_t i24;
+ rte_xmm_t i8;
+ uint32_t tbl[4];
+ uint64_t pt, pt2;
+ const uint32_t *ptbl;
+
+ const rte_xmm_t mask8 = {
+ .u32 = {UINT8_MAX, UINT8_MAX, UINT8_MAX, UINT8_MAX}};
+
+ /*
+ * RTE_LPM_VALID_EXT_ENTRY_BITMASK for 2 LPM entries
+ * as one 64-bit value (0x0300000003000000).
+ */
+ const uint64_t mask_xv =
+ ((uint64_t)RTE_LPM_VALID_EXT_ENTRY_BITMASK |
+ (uint64_t)RTE_LPM_VALID_EXT_ENTRY_BITMASK << 32);
+
+ /*
+ * RTE_LPM_LOOKUP_SUCCESS for 2 LPM entries
+ * as one 64-bit value (0x0100000001000000).
+ */
+ const uint64_t mask_v =
+ ((uint64_t)RTE_LPM_LOOKUP_SUCCESS |
+ (uint64_t)RTE_LPM_LOOKUP_SUCCESS << 32);
+
+ /* get 4 indexes for tbl24[]. */
+ i24.x = ip;
+ i24.u32[0] >>= CHAR_BIT;
+ i24.u32[1] >>= CHAR_BIT;
+ i24.u32[2] >>= CHAR_BIT;
+ i24.u32[3] >>= CHAR_BIT;
+
+ /* extract values from tbl24[] */
+ ptbl = (const uint32_t *)&lpm->tbl24[i24.u32[0]];
+ tbl[0] = *ptbl;
+ ptbl = (const uint32_t *)&lpm->tbl24[i24.u32[1]];
+ tbl[1] = *ptbl;
+ ptbl = (const uint32_t *)&lpm->tbl24[i24.u32[2]];
+ tbl[2] = *ptbl;
+ ptbl = (const uint32_t *)&lpm->tbl24[i24.u32[3]];
+ tbl[3] = *ptbl;
+
+ /* get 4 indexes for tbl8[]. */
+ i8.x = ip;
+ i8.u64[0] &= mask8.u64[0];
+ i8.u64[1] &= mask8.u64[1];
+
+ pt = (uint64_t)tbl[0] |
+ (uint64_t)tbl[1] << 32;
+ pt2 = (uint64_t)tbl[2] |
+ (uint64_t)tbl[3] << 32;
+
+ /* search successfully finished for all 4 IP addresses. */
+ if (likely((pt & mask_xv) == mask_v) &&
+ likely((pt2 & mask_xv) == mask_v)) {
+ *(uint64_t *)hop = pt & RTE_LPM_MASKX4_RES;
+ *(uint64_t *)(hop + 2) = pt2 & RTE_LPM_MASKX4_RES;
+ return;
+ }
+
+ if (unlikely((pt & RTE_LPM_VALID_EXT_ENTRY_BITMASK) ==
+ RTE_LPM_VALID_EXT_ENTRY_BITMASK)) {
+ i8.u32[0] = i8.u32[0] +
+ (tbl[0] & 0x00FFFFFF) * RTE_LPM_TBL8_GROUP_NUM_ENTRIES;
+ ptbl = (const uint32_t *)&lpm->tbl8[i8.u32[0]];
+ tbl[0] = *ptbl;
+ }
+ if (unlikely((pt >> 32 & RTE_LPM_VALID_EXT_ENTRY_BITMASK) ==
+ RTE_LPM_VALID_EXT_ENTRY_BITMASK)) {
+ i8.u32[1] = i8.u32[1] +
+ (tbl[1] & 0x00FFFFFF) * RTE_LPM_TBL8_GROUP_NUM_ENTRIES;
+ ptbl = (const uint32_t *)&lpm->tbl8[i8.u32[1]];
+ tbl[1] = *ptbl;
+ }
+ if (unlikely((pt2 & RTE_LPM_VALID_EXT_ENTRY_BITMASK) ==
+ RTE_LPM_VALID_EXT_ENTRY_BITMASK)) {
+ i8.u32[2] = i8.u32[2] +
+ (tbl[2] & 0x00FFFFFF) * RTE_LPM_TBL8_GROUP_NUM_ENTRIES;
+ ptbl = (const uint32_t *)&lpm->tbl8[i8.u32[2]];
+ tbl[2] = *ptbl;
+ }
+ if (unlikely((pt2 >> 32 & RTE_LPM_VALID_EXT_ENTRY_BITMASK) ==
+ RTE_LPM_VALID_EXT_ENTRY_BITMASK)) {
+ i8.u32[3] = i8.u32[3] +
+ (tbl[3] & 0x00FFFFFF) * RTE_LPM_TBL8_GROUP_NUM_ENTRIES;
+ ptbl = (const uint32_t *)&lpm->tbl8[i8.u32[3]];
+ tbl[3] = *ptbl;
+ }
+
+ hop[0] = (tbl[0] & RTE_LPM_LOOKUP_SUCCESS) ? tbl[0] & 0x00FFFFFF : defv;
+ hop[1] = (tbl[1] & RTE_LPM_LOOKUP_SUCCESS) ? tbl[1] & 0x00FFFFFF : defv;
+ hop[2] = (tbl[2] & RTE_LPM_LOOKUP_SUCCESS) ? tbl[2] & 0x00FFFFFF : defv;
+ hop[3] = (tbl[3] & RTE_LPM_LOOKUP_SUCCESS) ? tbl[3] & 0x00FFFFFF : defv;
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _RTE_LPM_SCALAR_H_ */
--
2.30.2
