From: Konstantin Ananyev <konstantin.v.ananyev@yandex.ru>
To: Rahul Bhansali <rbhansali@marvell.com>,
"dev@dpdk.org" <dev@dpdk.org>,
Ruifeng Wang <ruifeng.wang@arm.com>
Cc: Jerin Jacob Kollanukkaran <jerinj@marvell.com>
Subject: Re: [PATCH v2 1/2] examples/l3fwd: common packet group functionality
Date: Tue, 21 Jun 2022 00:13:14 +0100 [thread overview]
Message-ID: <96dac197-a384-f14c-3704-26239a5781ae@yandex.ru> (raw)
In-Reply-To: <PH0PR18MB384635BD02378719E8C71ADDB8AF9@PH0PR18MB3846.namprd18.prod.outlook.com>
17/06/2022 08:50, Rahul Bhansali пишет:
> CC: Konstantin Ananyev
>
>> -----Original Message-----
>> From: Rahul Bhansali <rbhansali@marvell.com>
>> Sent: Friday, June 17, 2022 1:13 PM
>> To: dev@dpdk.org; Ruifeng Wang <ruifeng.wang@arm.com>
>> Cc: Jerin Jacob Kollanukkaran <jerinj@marvell.com>; Rahul Bhansali
>> <rbhansali@marvell.com>
>> Subject: [PATCH v2 1/2] examples/l3fwd: common packet group functionality
>>
>> This will make the packet grouping function common, so that other examples
>> can utilize as per need.
>>
>> Signed-off-by: Rahul Bhansali <rbhansali@marvell.com>
>> ---
>> Changes in v2: New patch to address review comment.
>>
>> examples/common/neon_common.h | 50 ++++++++++++
>> examples/common/pkt_group.h | 139
>> ++++++++++++++++++++++++++++++++++
>> examples/l3fwd/Makefile | 5 +-
>> examples/l3fwd/l3fwd.h | 2 -
>> examples/l3fwd/l3fwd_common.h | 129 +------------------------------
>> examples/l3fwd/l3fwd_neon.h | 43 +----------
>> examples/meson.build | 2 +-
>> 7 files changed, 198 insertions(+), 172 deletions(-) create mode 100644
>> examples/common/neon_common.h create mode 100644
>> examples/common/pkt_group.h
>>
>> diff --git a/examples/common/neon_common.h
>> b/examples/common/neon_common.h new file mode 100644 index
>> 0000000000..f01b5ab6bc
>> --- /dev/null
>> +++ b/examples/common/neon_common.h
>> @@ -0,0 +1,50 @@
>> +/* SPDX-License-Identifier: BSD-3-Clause
>> + * Copyright(c) 2016-2018 Intel Corporation.
>> + * Copyright(c) 2017-2018 Linaro Limited.
>> + * Copyright(C) 2022 Marvell.
>> + */
>> +
>> +#ifndef _NEON_COMMON_H_
>> +#define _NEON_COMMON_H_
>> +
>> +#include "pkt_group.h"
>> +
>> +/*
>> + * Group consecutive packets with the same destination port in bursts of 4.
>> + * Suppose we have array of destination ports:
>> + * dst_port[] = {a, b, c, d,, e, ... }
>> + * dp1 should contain: <a, b, c, d>, dp2: <b, c, d, e>.
>> + * We doing 4 comparisons at once and the result is 4 bit mask.
>> + * This mask is used as an index into prebuild array of pnum values.
>> + */
>> +static inline uint16_t *
>> +neon_port_groupx4(uint16_t pn[FWDSTEP + 1], uint16_t *lp, uint16x8_t dp1,
>> + uint16x8_t dp2)
>> +{
>> + union {
>> + uint16_t u16[FWDSTEP + 1];
>> + uint64_t u64;
>> + } *pnum = (void *)pn;
>> +
>> + uint16x8_t mask = {1, 2, 4, 8, 0, 0, 0, 0};
>> + int32_t v;
>> +
>> + dp1 = vceqq_u16(dp1, dp2);
>> + dp1 = vandq_u16(dp1, mask);
>> + v = vaddvq_u16(dp1);
>> +
>> + /* update last port counter. */hh
>> + lp[0] += gptbl[v].lpv;
>> + rte_compiler_barrier();
>> +
>> + /* if dest port value has changed. */
>> + if (v != GRPMSK) {
>> + pnum->u64 = gptbl[v].pnum;
>> + pnum->u16[FWDSTEP] = 1;
>> + lp = pnum->u16 + gptbl[v].idx;
>> + }
>> +
>> + return lp;
>> +}
Thanks for the effort.
As I can see this function: port_groupx4() is nearly identical for all 3
platforms: sse/nenon/altivec (except of course built-in arch-specific
instincts).
In fact, even comemnts are identical.
I wonder can we have something like:
examples/common/<arch>/port_group.h
and for each arch will have defined port_groupx4(...)
?
>> +
>> +#endif /* _NEON_COMMON_H_ */
>> diff --git a/examples/common/pkt_group.h b/examples/common/pkt_group.h
>> new file mode 100644 index 0000000000..8b26d9380f
>> --- /dev/null
>> +++ b/examples/common/pkt_group.h
>> @@ -0,0 +1,139 @@
>> +/* SPDX-License-Identifier: BSD-3-Clause
>> + * Copyright(c) 2016-2018 Intel Corporation.
>> + * Copyright(c) 2017-2018 Linaro Limited.
>> + * Copyright(C) 2022 Marvell.
>> + */
>> +
>> +#ifndef _PKT_GROUP_H_
>> +#define _PKT_GROUP_H_
>> +
>> +#define FWDSTEP 4
>> +
>> +/*
>> + * Group consecutive packets with the same destination port into one burst.
>> + * To avoid extra latency this is done together with some other packet
>> + * processing, but after we made a final decision about packet's destination.
>> + * To do this we maintain:
>> + * pnum - array of number of consecutive packets with the same dest
>> +port for
>> + * each packet in the input burst.
>> + * lp - pointer to the last updated element in the pnum.
>> + * dlp - dest port value lp corresponds to.
>> + */
>> +
>> +#define GRPSZ (1 << FWDSTEP)
>> +#define GRPMSK (GRPSZ - 1)
>> +
>> +#define GROUP_PORT_STEP(dlp, dcp, lp, pn, idx) do { \
>> + if (likely((dlp) == (dcp)[(idx)])) { \
>> + (lp)[0]++; \
>> + } else { \
>> + (dlp) = (dcp)[idx]; \
>> + (lp) = (pn) + (idx); \
>> + (lp)[0] = 1; \
>> + } \
>> +} while (0)
>> +
>> +static const struct {
>> + uint64_t pnum; /* prebuild 4 values for pnum[]. */
>> + int32_t idx; /* index for new last updated elemnet. */
>> + uint16_t lpv; /* add value to the last updated element. */ }
>> +gptbl[GRPSZ] = {
>> + {
>> + /* 0: a != b, b != c, c != d, d != e */
>> + .pnum = UINT64_C(0x0001000100010001),
>> + .idx = 4,
>> + .lpv = 0,
>> + },
>> + {
>> + /* 1: a == b, b != c, c != d, d != e */
>> + .pnum = UINT64_C(0x0001000100010002),
>> + .idx = 4,
>> + .lpv = 1,
>> + },
>> + {
>> + /* 2: a != b, b == c, c != d, d != e */
>> + .pnum = UINT64_C(0x0001000100020001),
>> + .idx = 4,
>> + .lpv = 0,
>> + },
>> + {
>> + /* 3: a == b, b == c, c != d, d != e */
>> + .pnum = UINT64_C(0x0001000100020003),
>> + .idx = 4,
>> + .lpv = 2,
>> + },
>> + {
>> + /* 4: a != b, b != c, c == d, d != e */
>> + .pnum = UINT64_C(0x0001000200010001),
>> + .idx = 4,
>> + .lpv = 0,
>> + },
>> + {
>> + /* 5: a == b, b != c, c == d, d != e */
>> + .pnum = UINT64_C(0x0001000200010002),
>> + .idx = 4,
>> + .lpv = 1,
>> + },
>> + {
>> + /* 6: a != b, b == c, c == d, d != e */
>> + .pnum = UINT64_C(0x0001000200030001),
>> + .idx = 4,
>> + .lpv = 0,
>> + },
>> + {
>> + /* 7: a == b, b == c, c == d, d != e */
>> + .pnum = UINT64_C(0x0001000200030004),
>> + .idx = 4,
>> + .lpv = 3,
>> + },
>> + {
>> + /* 8: a != b, b != c, c != d, d == e */
>> + .pnum = UINT64_C(0x0002000100010001),
>> + .idx = 3,
>> + .lpv = 0,
>> + },
>> + {
>> + /* 9: a == b, b != c, c != d, d == e */
>> + .pnum = UINT64_C(0x0002000100010002),
>> + .idx = 3,
>> + .lpv = 1,
>> + },
>> + {
>> + /* 0xa: a != b, b == c, c != d, d == e */
>> + .pnum = UINT64_C(0x0002000100020001),
>> + .idx = 3,
>> + .lpv = 0,
>> + },
>> + {
>> + /* 0xb: a == b, b == c, c != d, d == e */
>> + .pnum = UINT64_C(0x0002000100020003),
>> + .idx = 3,
>> + .lpv = 2,
>> + },
>> + {
>> + /* 0xc: a != b, b != c, c == d, d == e */
>> + .pnum = UINT64_C(0x0002000300010001),
>> + .idx = 2,
>> + .lpv = 0,
>> + },
>> + {
>> + /* 0xd: a == b, b != c, c == d, d == e */
>> + .pnum = UINT64_C(0x0002000300010002),
>> + .idx = 2,
>> + .lpv = 1,
>> + },
>> + {
>> + /* 0xe: a != b, b == c, c == d, d == e */
>> + .pnum = UINT64_C(0x0002000300040001),
>> + .idx = 1,
>> + .lpv = 0,
>> + },
>> + {
>> + /* 0xf: a == b, b == c, c == d, d == e */
>> + .pnum = UINT64_C(0x0002000300040005),
>> + .idx = 0,
>> + .lpv = 4,
>> + },
>> +};
>> +
>> +#endif /* _PKT_GROUP_H_ */
>> diff --git a/examples/l3fwd/Makefile b/examples/l3fwd/Makefile index
>> 8efe6378e2..8dbe85c2e6 100644
>> --- a/examples/l3fwd/Makefile
>> +++ b/examples/l3fwd/Makefile
>> @@ -22,6 +22,7 @@ shared: build/$(APP)-shared
>> static: build/$(APP)-static
>> ln -sf $(APP)-static build/$(APP)
>>
>> +INCLUDES =-I../common
>> PC_FILE := $(shell $(PKGCONF) --path libdpdk 2>/dev/null) CFLAGS += -O3
>> $(shell $(PKGCONF) --cflags libdpdk) # Added for 'rte_eth_link_to_str()'
>> @@ -38,10 +39,10 @@ endif
>> endif
>>
>> build/$(APP)-shared: $(SRCS-y) Makefile $(PC_FILE) | build
>> - $(CC) $(CFLAGS) $(SRCS-y) -o $@ $(LDFLAGS) $(LDFLAGS_SHARED)
>> + $(CC) $(CFLAGS) $(SRCS-y) $(INCLUDES) -o $@ $(LDFLAGS)
>> +$(LDFLAGS_SHARED)
>>
>> build/$(APP)-static: $(SRCS-y) Makefile $(PC_FILE) | build
>> - $(CC) $(CFLAGS) $(SRCS-y) -o $@ $(LDFLAGS) $(LDFLAGS_STATIC)
>> + $(CC) $(CFLAGS) $(SRCS-y) $(INCLUDES) -o $@ $(LDFLAGS)
>> +$(LDFLAGS_STATIC)
>>
>> build:
>> @mkdir -p $@
>> diff --git a/examples/l3fwd/l3fwd.h b/examples/l3fwd/l3fwd.h index
>> 8a52c90755..40b5f32a9e 100644
>> --- a/examples/l3fwd/l3fwd.h
>> +++ b/examples/l3fwd/l3fwd.h
>> @@ -44,8 +44,6 @@
>> /* Used to mark destination port as 'invalid'. */
>> #define BAD_PORT ((uint16_t)-1)
>>
>> -#define FWDSTEP 4
>> -
>> /* replace first 12B of the ethernet header. */
>> #define MASK_ETH 0x3f
>>
>> diff --git a/examples/l3fwd/l3fwd_common.h
>> b/examples/l3fwd/l3fwd_common.h index 8e4c27218f..224b1c08e8 100644
>> --- a/examples/l3fwd/l3fwd_common.h
>> +++ b/examples/l3fwd/l3fwd_common.h
>> @@ -7,6 +7,8 @@
>> #ifndef _L3FWD_COMMON_H_
>> #define _L3FWD_COMMON_H_
>>
>> +#include "pkt_group.h"
>> +
>> #ifdef DO_RFC_1812_CHECKS
>>
>> #define IPV4_MIN_VER_IHL 0x45
>> @@ -50,133 +52,6 @@ rfc1812_process(struct rte_ipv4_hdr *ipv4_hdr, uint16_t
>> *dp, uint32_t ptype)
>> #define rfc1812_process(mb, dp, ptype) do { } while (0)
>> #endif /* DO_RFC_1812_CHECKS */
>>
>> -/*
>> - * We group consecutive packets with the same destination port into one burst.
>> - * To avoid extra latency this is done together with some other packet
>> - * processing, but after we made a final decision about packet's destination.
>> - * To do this we maintain:
>> - * pnum - array of number of consecutive packets with the same dest port for
>> - * each packet in the input burst.
>> - * lp - pointer to the last updated element in the pnum.
>> - * dlp - dest port value lp corresponds to.
>> - */
>> -
>> -#define GRPSZ (1 << FWDSTEP)
>> -#define GRPMSK (GRPSZ - 1)
>> -
>> -#define GROUP_PORT_STEP(dlp, dcp, lp, pn, idx) do { \
>> - if (likely((dlp) == (dcp)[(idx)])) { \
>> - (lp)[0]++; \
>> - } else { \
>> - (dlp) = (dcp)[idx]; \
>> - (lp) = (pn) + (idx); \
>> - (lp)[0] = 1; \
>> - } \
>> -} while (0)
>> -
>> -static const struct {
>> - uint64_t pnum; /* prebuild 4 values for pnum[]. */
>> - int32_t idx; /* index for new last updated element. */
>> - uint16_t lpv; /* add value to the last updated element. */
>> -} gptbl[GRPSZ] = {
>> - {
>> - /* 0: a != b, b != c, c != d, d != e */
>> - .pnum = UINT64_C(0x0001000100010001),
>> - .idx = 4,
>> - .lpv = 0,
>> - },
>> - {
>> - /* 1: a == b, b != c, c != d, d != e */
>> - .pnum = UINT64_C(0x0001000100010002),
>> - .idx = 4,
>> - .lpv = 1,
>> - },
>> - {
>> - /* 2: a != b, b == c, c != d, d != e */
>> - .pnum = UINT64_C(0x0001000100020001),
>> - .idx = 4,
>> - .lpv = 0,
>> - },
>> - {
>> - /* 3: a == b, b == c, c != d, d != e */
>> - .pnum = UINT64_C(0x0001000100020003),
>> - .idx = 4,
>> - .lpv = 2,
>> - },
>> - {
>> - /* 4: a != b, b != c, c == d, d != e */
>> - .pnum = UINT64_C(0x0001000200010001),
>> - .idx = 4,
>> - .lpv = 0,
>> - },
>> - {
>> - /* 5: a == b, b != c, c == d, d != e */
>> - .pnum = UINT64_C(0x0001000200010002),
>> - .idx = 4,
>> - .lpv = 1,
>> - },
>> - {
>> - /* 6: a != b, b == c, c == d, d != e */
>> - .pnum = UINT64_C(0x0001000200030001),
>> - .idx = 4,
>> - .lpv = 0,
>> - },
>> - {
>> - /* 7: a == b, b == c, c == d, d != e */
>> - .pnum = UINT64_C(0x0001000200030004),
>> - .idx = 4,
>> - .lpv = 3,
>> - },
>> - {
>> - /* 8: a != b, b != c, c != d, d == e */
>> - .pnum = UINT64_C(0x0002000100010001),
>> - .idx = 3,
>> - .lpv = 0,
>> - },
>> - {
>> - /* 9: a == b, b != c, c != d, d == e */
>> - .pnum = UINT64_C(0x0002000100010002),
>> - .idx = 3,
>> - .lpv = 1,
>> - },
>> - {
>> - /* 0xa: a != b, b == c, c != d, d == e */
>> - .pnum = UINT64_C(0x0002000100020001),
>> - .idx = 3,
>> - .lpv = 0,
>> - },
>> - {
>> - /* 0xb: a == b, b == c, c != d, d == e */
>> - .pnum = UINT64_C(0x0002000100020003),
>> - .idx = 3,
>> - .lpv = 2,
>> - },
>> - {
>> - /* 0xc: a != b, b != c, c == d, d == e */
>> - .pnum = UINT64_C(0x0002000300010001),
>> - .idx = 2,
>> - .lpv = 0,
>> - },
>> - {
>> - /* 0xd: a == b, b != c, c == d, d == e */
>> - .pnum = UINT64_C(0x0002000300010002),
>> - .idx = 2,
>> - .lpv = 1,
>> - },
>> - {
>> - /* 0xe: a != b, b == c, c == d, d == e */
>> - .pnum = UINT64_C(0x0002000300040001),
>> - .idx = 1,
>> - .lpv = 0,
>> - },
>> - {
>> - /* 0xf: a == b, b == c, c == d, d == e */
>> - .pnum = UINT64_C(0x0002000300040005),
>> - .idx = 0,
>> - .lpv = 4,
>> - },
>> -};
>> -
>> static __rte_always_inline void
>> send_packetsx4(struct lcore_conf *qconf, uint16_t port, struct rte_mbuf *m[],
>> uint32_t num)
>> diff --git a/examples/l3fwd/l3fwd_neon.h b/examples/l3fwd/l3fwd_neon.h
>> index e3d33a5229..5fa765b640 100644
>> --- a/examples/l3fwd/l3fwd_neon.h
>> +++ b/examples/l3fwd/l3fwd_neon.h
>> @@ -7,6 +7,7 @@
>> #define _L3FWD_NEON_H_
>>
>> #include "l3fwd.h"
>> +#include "neon_common.h"
>> #include "l3fwd_common.h"
>>
>> /*
>> @@ -62,44 +63,6 @@ processx4_step3(struct rte_mbuf *pkt[FWDSTEP],
>> uint16_t dst_port[FWDSTEP])
>> &dst_port[3], pkt[3]->packet_type);
>> }
>>
>> -/*
>> - * Group consecutive packets with the same destination port in bursts of 4.
>> - * Suppose we have array of destination ports:
>> - * dst_port[] = {a, b, c, d,, e, ... }
>> - * dp1 should contain: <a, b, c, d>, dp2: <b, c, d, e>.
>> - * We doing 4 comparisons at once and the result is 4 bit mask.
>> - * This mask is used as an index into prebuild array of pnum values.
>> - */
>> -static inline uint16_t *
>> -port_groupx4(uint16_t pn[FWDSTEP + 1], uint16_t *lp, uint16x8_t dp1,
>> - uint16x8_t dp2)
>> -{
>> - union {
>> - uint16_t u16[FWDSTEP + 1];
>> - uint64_t u64;
>> - } *pnum = (void *)pn;
>> -
>> - int32_t v;
>> - uint16x8_t mask = {1, 2, 4, 8, 0, 0, 0, 0};
>> -
>> - dp1 = vceqq_u16(dp1, dp2);
>> - dp1 = vandq_u16(dp1, mask);
>> - v = vaddvq_u16(dp1);
>> -
>> - /* update last port counter. */
>> - lp[0] += gptbl[v].lpv;
>> - rte_compiler_barrier();
>> -
>> - /* if dest port value has changed. */
>> - if (v != GRPMSK) {
>> - pnum->u64 = gptbl[v].pnum;
>> - pnum->u16[FWDSTEP] = 1;
>> - lp = pnum->u16 + gptbl[v].idx;
>> - }
>> -
>> - return lp;
>> -}
>> -
>> /**
>> * Process one packet:
>> * Update source and destination MAC addresses in the ethernet header.
>> @@ -161,7 +124,7 @@ send_packets_multi(struct lcore_conf *qconf, struct
>> rte_mbuf **pkts_burst,
>> * <d[j-3], d[j-2], d[j-1], d[j], ... >
>> */
>> dp2 = vld1q_u16(&dst_port[j - FWDSTEP + 1]);
>> - lp = port_groupx4(&pnum[j - FWDSTEP], lp, dp1, dp2);
>> + lp = neon_port_groupx4(&pnum[j - FWDSTEP], lp, dp1,
>> dp2);
>>
>> /*
>> * dp1:
>> @@ -175,7 +138,7 @@ send_packets_multi(struct lcore_conf *qconf, struct
>> rte_mbuf **pkts_burst,
>> */
>> dp2 = vextq_u16(dp1, dp1, 1);
>> dp2 = vsetq_lane_u16(vgetq_lane_u16(dp2, 2), dp2, 3);
>> - lp = port_groupx4(&pnum[j - FWDSTEP], lp, dp1, dp2);
>> + lp = neon_port_groupx4(&pnum[j - FWDSTEP], lp, dp1, dp2);
>>
>> /*
>> * remove values added by the last repeated diff --git
>> a/examples/meson.build b/examples/meson.build index
>> 78de0e1f37..81e93799f2 100644
>> --- a/examples/meson.build
>> +++ b/examples/meson.build
>> @@ -97,7 +97,7 @@ foreach example: examples
>> ldflags = default_ldflags
>>
>> ext_deps = []
>> - includes = [include_directories(example)]
>> + includes = [include_directories(example, 'common')]
>> deps = ['eal', 'mempool', 'net', 'mbuf', 'ethdev', 'cmdline']
>> subdir(example)
>>
>> --
>> 2.25.1
>
next prev parent reply other threads:[~2022-06-20 23:13 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-05-24 9:57 [PATCH] examples/ipsec-secgw: add support of NEON with poll mode Rahul Bhansali
2022-05-24 23:00 ` Konstantin Ananyev
2022-05-25 11:03 ` [EXT] " Rahul Bhansali
2022-05-27 11:44 ` Konstantin Ananyev
2022-06-17 7:42 ` [PATCH v2 1/2] examples/l3fwd: common packet group functionality Rahul Bhansali
2022-06-17 7:42 ` [PATCH v2 2/2] examples/ipsec-secgw: add support of NEON with poll mode Rahul Bhansali
2022-06-17 7:51 ` Rahul Bhansali
2022-06-21 12:55 ` Akhil Goyal
2022-06-23 8:46 ` Zhang, Roy Fan
2022-06-23 9:37 ` Rahul Bhansali
2022-06-17 7:50 ` [PATCH v2 1/2] examples/l3fwd: common packet group functionality Rahul Bhansali
2022-06-20 23:13 ` Konstantin Ananyev [this message]
2022-06-21 16:50 ` [EXT] " Rahul Bhansali
2022-06-22 23:25 ` Konstantin Ananyev
2022-06-20 7:49 ` [EXT] " Akhil Goyal
2022-06-20 10:45 ` Thomas Monjalon
2022-06-21 12:56 ` Akhil Goyal
2022-06-23 9:38 ` [PATCH v3 " Rahul Bhansali
2022-06-23 9:38 ` [PATCH v3 2/2] examples/ipsec-secgw: add support of NEON with poll mode Rahul Bhansali
2022-06-26 19:00 ` [PATCH v3 1/2] examples/l3fwd: common packet group functionality Konstantin Ananyev
2022-06-28 8:54 ` [EXT] " Akhil Goyal
2022-07-03 21:40 ` Thomas Monjalon
2022-07-04 12:49 ` [EXT] " Rahul Bhansali
2022-07-04 14:04 ` Thomas Monjalon
2022-07-04 14:48 ` Thomas Monjalon
2022-07-05 16:11 ` [EXT] " Rahul Bhansali
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