ligang/vpp
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

dpdk: improve perf of buffer indices calc in the input node

Browse Source 
Change-Id: I16557189aa4a763ec496cb4a45f6e12f2d46971f
Signed-off-by: Damjan Marion <damarion@cisco.com>
This commit is contained in:
Damjan Marion
2018-05-07 15:20:25 +02:00
committed by Florin Coras
parent 68e2ffb3ef
commit c755c05bd6
1 changed files with 55 additions and 36 deletions
Download Patch File Download Diff File Expand all files Collapse all files

91
src/plugins/dpdk/device/node.c
View File

@@ -214,37 +214,62 @@ poll_rate_limit (dpdk_main_t * dm)
*/
static_always_inline void
dpdk_mbuf_to_buffer_index_x4 (vlib_main_t * vm, struct rte_mbuf **mb,
u32 * buffers)
dpdk_mbufs_to_buffer_indices (vlib_main_t * vm, struct rte_mbuf **mb,
u32 * bi, uword n_left)
{
#ifdef CLIB_HAVE_VEC256
vlib_buffer_main_t *bm = &buffer_main;
u64x4 v = *(u64x4 *) mb;
u32x8 v2, mask = { 0, 2, 4, 6, 1, 3, 5, 7 };
/* load 4 pointers into 256-bit register */
v = u64x4_load_unaligned (mb);
/* vlib_buffer_t is straight after rte_mbuf so advance all 4
pointers for size of rte_mbuf */
v += u64x4_splat (sizeof (struct rte_mbuf));
/* calculate 4 buffer indices in paralled */
v = (v - u64x4_splat (bm->buffer_mem_start)) >> CLIB_LOG2_CACHE_LINE_BYTES;
/* permute 256-bit register so lower u32s of each buffer index are
* placed into lower 128-bits */
v2 = u32x8_permute ((u32x8) v, mask);
/* extract lower 128-bits and save them to the array of buffer indices */
u32x4_store_unaligned (u32x8_extract_lo (v2), buffers);
#else
/* equivalent non-nector implementation */
buffers[0] = vlib_get_buffer_index (vm, vlib_buffer_from_rte_mbuf (mb[0]));
buffers[1] = vlib_get_buffer_index (vm, vlib_buffer_from_rte_mbuf (mb[1]));
buffers[2] = vlib_get_buffer_index (vm, vlib_buffer_from_rte_mbuf (mb[2]));
buffers[3] = vlib_get_buffer_index (vm, vlib_buffer_from_rte_mbuf (mb[3]));
u32x8 mask = { 0, 2, 4, 6, 1, 3, 5, 7 };
u64x4 off4 = u64x4_splat (buffer_main.buffer_mem_start -
sizeof (struct rte_mbuf));
#endif
while (n_left >= 8)
{
#ifdef CLIB_HAVE_VEC256
/* load 4 pointers into 256-bit register */
u64x4 v0 = u64x4_load_unaligned (mb);
u64x4 v1 = u64x4_load_unaligned (mb + 4);
u32x8 v2, v3;
/* calculate 4 buffer indices in parallel
vlib_buffer_t is straight after rte_mbuf so advance all 4
pointers for size of rte_mbuf */
v0 -= off4;
v1 -= off4;
v0 >>= CLIB_LOG2_CACHE_LINE_BYTES;
v1 >>= CLIB_LOG2_CACHE_LINE_BYTES;
/* permute 256-bit register so lower u32s of each buffer index are
* placed into lower 128-bits */
v2 = u32x8_permute ((u32x8) v0, mask);
v3 = u32x8_permute ((u32x8) v1, mask);
/* extract lower 128-bits and save them to the array of buffer indices */
u32x4_store_unaligned (u32x8_extract_lo (v2), bi);
u32x4_store_unaligned (u32x8_extract_lo (v3), bi + 4);
#else
/* equivalent non-nector implementation */
bi[0] = vlib_get_buffer_index (vm, vlib_buffer_from_rte_mbuf (mb[0]));
bi[1] = vlib_get_buffer_index (vm, vlib_buffer_from_rte_mbuf (mb[1]));
bi[2] = vlib_get_buffer_index (vm, vlib_buffer_from_rte_mbuf (mb[2]));
bi[3] = vlib_get_buffer_index (vm, vlib_buffer_from_rte_mbuf (mb[3]));
bi[4] = vlib_get_buffer_index (vm, vlib_buffer_from_rte_mbuf (mb[4]));
bi[5] = vlib_get_buffer_index (vm, vlib_buffer_from_rte_mbuf (mb[4]));
bi[6] = vlib_get_buffer_index (vm, vlib_buffer_from_rte_mbuf (mb[6]));
bi[7] = vlib_get_buffer_index (vm, vlib_buffer_from_rte_mbuf (mb[7]));
#endif
bi += 8;
mb += 8;
n_left -= 8;
}
while (n_left)
{
bi[0] = vlib_get_buffer_index (vm, vlib_buffer_from_rte_mbuf (mb[0]));
bi += 1;
mb += 1;
n_left -= 1;
}
}
static_always_inline u8
@@ -539,6 +564,7 @@ dpdk_device_input (vlib_main_t * vm, dpdk_main_t * dm, dpdk_device_t * xd,
}
/* enqueue buffers to the next node */
dpdk_mbufs_to_buffer_indices (vm, ptd->mbufs, ptd->buffers, n_rx_packets);
n_left = n_rx_packets;
next = ptd->next;
buffers = ptd->buffers;
@@ -554,10 +580,6 @@ dpdk_device_input (vlib_main_t * vm, dpdk_main_t * dm, dpdk_device_t * xd,
u16x16 next16 = u16x16_load_unaligned (next);
if (u16x16_is_all_equal (next16, next_index))
{
dpdk_mbuf_to_buffer_index_x4 (vm, mb, buffers);
dpdk_mbuf_to_buffer_index_x4 (vm, mb + 4, buffers + 4);
dpdk_mbuf_to_buffer_index_x4 (vm, mb + 8, buffers + 8);
dpdk_mbuf_to_buffer_index_x4 (vm, mb + 12, buffers + 12);
clib_memcpy (to_next, buffers, 16 * sizeof (u32));
to_next += 16;
n_left_to_next -= 16;
@@ -568,7 +590,6 @@ dpdk_device_input (vlib_main_t * vm, dpdk_main_t * dm, dpdk_device_t * xd,
}
else
{
dpdk_mbuf_to_buffer_index_x4 (vm, mb, buffers);
clib_memcpy (to_next, buffers, 4 * sizeof (u32));
to_next += 4;
n_left_to_next -= 4;
@@ -588,7 +609,6 @@ dpdk_device_input (vlib_main_t * vm, dpdk_main_t * dm, dpdk_device_t * xd,
#endif
while (n_left >= 4 && n_left_to_next >= 4)
{
dpdk_mbuf_to_buffer_index_x4 (vm, mb, buffers);
clib_memcpy (to_next, buffers, 4 * sizeof (u32));
to_next += 4;
n_left_to_next -= 4;
@@ -606,8 +626,7 @@ dpdk_device_input (vlib_main_t * vm, dpdk_main_t * dm, dpdk_device_t * xd,
}
while (n_left && n_left_to_next)
{
to_next[0] = buffers[0] =
vlib_get_buffer_index (vm, vlib_buffer_from_rte_mbuf (mb[0]));
clib_memcpy (to_next, buffers, 1 * sizeof (u32));
to_next += 1;
n_left_to_next -= 1;
vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,