From d3cb7ba2ab042cbfb580ea3f01e41e98d41d0508 Mon Sep 17 00:00:00 2001 From: Nitin Saxena Date: Wed, 7 Feb 2018 11:32:00 +0000 Subject: [PATCH] vhost: Added ARMV8 NEON version of function map_guest_mem() (VPP-1085) The NEON implementation searches particular address in VHOST_MEMORY_MAX_NREGIONS regions. Searching two regions at a time. Change-Id: Icc3c6746bc98e3a1fa71424e51b64f62efbfdc74 Signed-off-by: Nitin Saxena --- src/vnet/devices/virtio/vhost-user.c | 69 ++++++++++++++++++++++++++++++++++++ 1 file changed, 69 insertions(+) diff --git a/src/vnet/devices/virtio/vhost-user.c b/src/vnet/devices/virtio/vhost-user.c index 9c93ef4ebfb..be3405488fe 100644 --- a/src/vnet/devices/virtio/vhost-user.c +++ b/src/vnet/devices/virtio/vhost-user.c @@ -256,7 +256,76 @@ map_guest_mem (vhost_user_intf_t * vui, uword addr, u32 * hint) return (void *) (vui->region_mmap_addr[i] + addr - vui->regions[i].guest_phys_addr); } +#elif __aarch64__ && __ARM_NEON + uint64x2_t al, ah, rl, rh, r; + uint32_t u32 = 0; + al = vdupq_n_u64 (addr + 1); + ah = vdupq_n_u64 (addr); + + /*First Iteration */ + rl = vld1q_u64 (&vui->region_guest_addr_lo[0]); + rl = vcgtq_u64 (al, rl); + rh = vld1q_u64 (&vui->region_guest_addr_hi[0]); + rh = vcgtq_u64 (rh, ah); + r = vandq_u64 (rl, rh); + u32 |= (vgetq_lane_u8 (vreinterpretq_u8_u64 (r), 0) & 0x1); + u32 |= ((vgetq_lane_u8 (vreinterpretq_u8_u64 (r), 8) & 0x1) << 1); + + if (u32) + { + i = __builtin_ctzll (u32); + goto vhost_map_guest_mem_done; + } + + /*Second Iteration */ + rl = vld1q_u64 (&vui->region_guest_addr_lo[2]); + rl = vcgtq_u64 (al, rl); + rh = vld1q_u64 (&vui->region_guest_addr_hi[2]); + rh = vcgtq_u64 (rh, ah); + r = vandq_u64 (rl, rh); + u32 |= ((vgetq_lane_u8 (vreinterpretq_u8_u64 (r), 0) & 0x1) << 2); + u32 |= ((vgetq_lane_u8 (vreinterpretq_u8_u64 (r), 8) & 0x1) << 3); + + if (u32) + { + i = __builtin_ctzll (u32); + goto vhost_map_guest_mem_done; + } + + /*Third Iteration */ + rl = vld1q_u64 (&vui->region_guest_addr_lo[4]); + rl = vcgtq_u64 (al, rl); + rh = vld1q_u64 (&vui->region_guest_addr_hi[4]); + rh = vcgtq_u64 (rh, ah); + r = vandq_u64 (rl, rh); + u32 |= ((vgetq_lane_u8 (vreinterpretq_u8_u64 (r), 0) & 0x1) << 4); + u32 |= ((vgetq_lane_u8 (vreinterpretq_u8_u64 (r), 8) & 0x1) << 5); + + if (u32) + { + i = __builtin_ctzll (u32); + goto vhost_map_guest_mem_done; + } + + /*Fourth Iteration */ + rl = vld1q_u64 (&vui->region_guest_addr_lo[6]); + rl = vcgtq_u64 (al, rl); + rh = vld1q_u64 (&vui->region_guest_addr_hi[6]); + rh = vcgtq_u64 (rh, ah); + r = vandq_u64 (rl, rh); + u32 |= ((vgetq_lane_u8 (vreinterpretq_u8_u64 (r), 0) & 0x1) << 6); + u32 |= ((vgetq_lane_u8 (vreinterpretq_u8_u64 (r), 8) & 0x1) << 7); + + i = __builtin_ctzll (u32 | (1 << VHOST_MEMORY_MAX_NREGIONS)); + +vhost_map_guest_mem_done: + if (i < vui->nregions) + { + *hint = i; + return (void *) (vui->region_mmap_addr[i] + addr - + vui->regions[i].guest_phys_addr); + } #else for (i = 0; i < vui->nregions; i++) { -- 2.16.6