diff options
| author |   Damjan Marion <damarion@cisco.com> | 2020-04-23 13:41:47 +0200 |
|---|---|---|
| committer | Damjan Marion <damarion@cisco.com> | 2020-04-23 13:45:25 +0200 |
| commit | 68e5fd5206e75cb367375b4fea2e531a3712fd06 (patch) | |
| tree | 857b29b0a960a4147c6009cf2edc70bdc0ca7be3 /src/vppinfra/clib.h | |
| parent | 59f71132edffcfa1b94c400736575bd55bdbd7d7 (diff) | |
vppinfra: more bihash optimizatons
* Avoid doing expensive bit extraction for most likely case where bucket
.log2_page_size == 0 and .linear_search == 0, saves 3-5 cycles for
lookup, data_prefetch and add operation
* use bextr instruction when available (x86 BMI instruction set)
Type: improvement
Change-Id: I163df36a29287482c5f133be8b21d62a2f7440de
Signed-off-by: Damjan Marion <damarion@cisco.com>
Diffstat (limited to 'src/vppinfra/clib.h')
| -rw-r--r-- | src/vppinfra/clib.h | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/src/vppinfra/clib.h b/src/vppinfra/clib.h index dac41adb165..bdea43b3fe0 100644 --- a/src/vppinfra/clib.h +++ b/src/vppinfra/clib.h @@ -40,6 +40,10 @@ #include <vppinfra/config.h> +#ifdef __x86_64__ +#include <x86intrin.h> +#endif + /* Standalone means to not assume we are running on a Unix box. */ #if ! defined (CLIB_STANDALONE) && ! defined (CLIB_LINUX_KERNEL) #define CLIB_UNIX @@ -293,6 +297,15 @@ flt_round_to_multiple (f64 x, f64 f) return f * flt_round_nearest (x / f); } +always_inline uword +extract_bits (uword x, int start, int count) +{ +#ifdef __BMI__ + return _bextr_u64 (x, start, count); +#endif + return (x >> start) & pow2_mask (count); +} + #define clib_max(x,y) \ ({ \ __typeof__ (x) _x = (x); \ |