mirror_zfs/lib/libspl/include/sys/simd.h
Attila Fülöp 31b160f0a6
ICP: Improve AES-GCM performance
Currently SIMD accelerated AES-GCM performance is limited by two
factors:

a. The need to disable preemption and interrupts and save the FPU
state before using it and to do the reverse when done. Due to the
way the code is organized (see (b) below) we have to pay this price
twice for each 16 byte GCM block processed.

b. Most processing is done in C, operating on single GCM blocks.
The use of SIMD instructions is limited to the AES encryption of the
counter block (AES-NI) and the Galois multiplication (PCLMULQDQ).
This leads to the FPU not being fully utilized for crypto
operations.

To solve (a) we do crypto processing in larger chunks while owning
the FPU. An `icp_gcm_avx_chunk_size` module parameter was introduced
to make this chunk size tweakable. It defaults to 32 KiB. This step
alone roughly doubles performance. (b) is tackled by porting and
using the highly optimized openssl AES-GCM assembler routines, which
do all the processing (CTR, AES, GMULT) in a single routine. Both
steps together result in up to 32x reduction of the time spend in
the en/decryption routines, leading up to approximately 12x
throughput increase for large (128 KiB) blocks.

Lastly, this commit changes the default encryption algorithm from
AES-CCM to AES-GCM when setting the `encryption=on` property.

Reviewed-By: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-By: Jason King <jason.king@joyent.com>
Reviewed-By: Tom Caputi <tcaputi@datto.com>
Reviewed-By: Richard Laager <rlaager@wiktel.com>
Signed-off-by: Attila Fülöp <attila@fueloep.org>
Closes #9749
2020-02-10 12:59:50 -08:00

503 lines
11 KiB
C

/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2006 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#ifndef _LIBSPL_SYS_SIMD_H
#define _LIBSPL_SYS_SIMD_H
#include <sys/isa_defs.h>
#include <sys/types.h>
#if defined(__x86)
#include <cpuid.h>
#define kfpu_allowed() 1
#define kfpu_begin() do {} while (0)
#define kfpu_end() do {} while (0)
#define kfpu_init() 0
#define kfpu_fini() ((void) 0)
/*
* CPUID feature tests for user-space.
*
* x86 registers used implicitly by CPUID
*/
typedef enum cpuid_regs {
EAX = 0,
EBX,
ECX,
EDX,
CPUID_REG_CNT = 4
} cpuid_regs_t;
/*
* List of instruction sets identified by CPUID
*/
typedef enum cpuid_inst_sets {
SSE = 0,
SSE2,
SSE3,
SSSE3,
SSE4_1,
SSE4_2,
OSXSAVE,
AVX,
AVX2,
BMI1,
BMI2,
AVX512F,
AVX512CD,
AVX512DQ,
AVX512BW,
AVX512IFMA,
AVX512VBMI,
AVX512PF,
AVX512ER,
AVX512VL,
AES,
PCLMULQDQ,
MOVBE
} cpuid_inst_sets_t;
/*
* Instruction set descriptor.
*/
typedef struct cpuid_feature_desc {
uint32_t leaf; /* CPUID leaf */
uint32_t subleaf; /* CPUID sub-leaf */
uint32_t flag; /* bit mask of the feature */
cpuid_regs_t reg; /* which CPUID return register to test */
} cpuid_feature_desc_t;
#define _AVX512F_BIT (1U << 16)
#define _AVX512CD_BIT (_AVX512F_BIT | (1U << 28))
#define _AVX512DQ_BIT (_AVX512F_BIT | (1U << 17))
#define _AVX512BW_BIT (_AVX512F_BIT | (1U << 30))
#define _AVX512IFMA_BIT (_AVX512F_BIT | (1U << 21))
#define _AVX512VBMI_BIT (1U << 1) /* AVX512F_BIT is on another leaf */
#define _AVX512PF_BIT (_AVX512F_BIT | (1U << 26))
#define _AVX512ER_BIT (_AVX512F_BIT | (1U << 27))
#define _AVX512VL_BIT (1U << 31) /* if used also check other levels */
#define _AES_BIT (1U << 25)
#define _PCLMULQDQ_BIT (1U << 1)
#define _MOVBE_BIT (1U << 22)
/*
* Descriptions of supported instruction sets
*/
static const cpuid_feature_desc_t cpuid_features[] = {
[SSE] = {1U, 0U, 1U << 25, EDX },
[SSE2] = {1U, 0U, 1U << 26, EDX },
[SSE3] = {1U, 0U, 1U << 0, ECX },
[SSSE3] = {1U, 0U, 1U << 9, ECX },
[SSE4_1] = {1U, 0U, 1U << 19, ECX },
[SSE4_2] = {1U, 0U, 1U << 20, ECX },
[OSXSAVE] = {1U, 0U, 1U << 27, ECX },
[AVX] = {1U, 0U, 1U << 28, ECX },
[AVX2] = {7U, 0U, 1U << 5, EBX },
[BMI1] = {7U, 0U, 1U << 3, EBX },
[BMI2] = {7U, 0U, 1U << 8, EBX },
[AVX512F] = {7U, 0U, _AVX512F_BIT, EBX },
[AVX512CD] = {7U, 0U, _AVX512CD_BIT, EBX },
[AVX512DQ] = {7U, 0U, _AVX512DQ_BIT, EBX },
[AVX512BW] = {7U, 0U, _AVX512BW_BIT, EBX },
[AVX512IFMA] = {7U, 0U, _AVX512IFMA_BIT, EBX },
[AVX512VBMI] = {7U, 0U, _AVX512VBMI_BIT, ECX },
[AVX512PF] = {7U, 0U, _AVX512PF_BIT, EBX },
[AVX512ER] = {7U, 0U, _AVX512ER_BIT, EBX },
[AVX512VL] = {7U, 0U, _AVX512ER_BIT, EBX },
[AES] = {1U, 0U, _AES_BIT, ECX },
[PCLMULQDQ] = {1U, 0U, _PCLMULQDQ_BIT, ECX },
[MOVBE] = {1U, 0U, _MOVBE_BIT, ECX },
};
/*
* Check if OS supports AVX and AVX2 by checking XCR0
* Only call this function if CPUID indicates that AVX feature is
* supported by the CPU, otherwise it might be an illegal instruction.
*/
static inline uint64_t
xgetbv(uint32_t index)
{
uint32_t eax, edx;
/* xgetbv - instruction byte code */
__asm__ __volatile__(".byte 0x0f; .byte 0x01; .byte 0xd0"
: "=a" (eax), "=d" (edx)
: "c" (index));
return ((((uint64_t)edx)<<32) | (uint64_t)eax);
}
/*
* Check if CPU supports a feature
*/
static inline boolean_t
__cpuid_check_feature(const cpuid_feature_desc_t *desc)
{
uint32_t r[CPUID_REG_CNT];
if (__get_cpuid_max(0, NULL) >= desc->leaf) {
/*
* __cpuid_count is needed to properly check
* for AVX2. It is a macro, so return parameters
* are passed by value.
*/
__cpuid_count(desc->leaf, desc->subleaf,
r[EAX], r[EBX], r[ECX], r[EDX]);
return ((r[desc->reg] & desc->flag) == desc->flag);
}
return (B_FALSE);
}
#define CPUID_FEATURE_CHECK(name, id) \
static inline boolean_t \
__cpuid_has_ ## name(void) \
{ \
return (__cpuid_check_feature(&cpuid_features[id])); \
}
/*
* Define functions for user-space CPUID features testing
*/
CPUID_FEATURE_CHECK(sse, SSE);
CPUID_FEATURE_CHECK(sse2, SSE2);
CPUID_FEATURE_CHECK(sse3, SSE3);
CPUID_FEATURE_CHECK(ssse3, SSSE3);
CPUID_FEATURE_CHECK(sse4_1, SSE4_1);
CPUID_FEATURE_CHECK(sse4_2, SSE4_2);
CPUID_FEATURE_CHECK(avx, AVX);
CPUID_FEATURE_CHECK(avx2, AVX2);
CPUID_FEATURE_CHECK(osxsave, OSXSAVE);
CPUID_FEATURE_CHECK(bmi1, BMI1);
CPUID_FEATURE_CHECK(bmi2, BMI2);
CPUID_FEATURE_CHECK(avx512f, AVX512F);
CPUID_FEATURE_CHECK(avx512cd, AVX512CD);
CPUID_FEATURE_CHECK(avx512dq, AVX512DQ);
CPUID_FEATURE_CHECK(avx512bw, AVX512BW);
CPUID_FEATURE_CHECK(avx512ifma, AVX512IFMA);
CPUID_FEATURE_CHECK(avx512vbmi, AVX512VBMI);
CPUID_FEATURE_CHECK(avx512pf, AVX512PF);
CPUID_FEATURE_CHECK(avx512er, AVX512ER);
CPUID_FEATURE_CHECK(avx512vl, AVX512VL);
CPUID_FEATURE_CHECK(aes, AES);
CPUID_FEATURE_CHECK(pclmulqdq, PCLMULQDQ);
CPUID_FEATURE_CHECK(movbe, MOVBE);
/*
* Detect register set support
*/
static inline boolean_t
__simd_state_enabled(const uint64_t state)
{
boolean_t has_osxsave;
uint64_t xcr0;
has_osxsave = __cpuid_has_osxsave();
if (!has_osxsave)
return (B_FALSE);
xcr0 = xgetbv(0);
return ((xcr0 & state) == state);
}
#define _XSTATE_SSE_AVX (0x2 | 0x4)
#define _XSTATE_AVX512 (0xE0 | _XSTATE_SSE_AVX)
#define __ymm_enabled() __simd_state_enabled(_XSTATE_SSE_AVX)
#define __zmm_enabled() __simd_state_enabled(_XSTATE_AVX512)
/*
* Check if SSE instruction set is available
*/
static inline boolean_t
zfs_sse_available(void)
{
return (__cpuid_has_sse());
}
/*
* Check if SSE2 instruction set is available
*/
static inline boolean_t
zfs_sse2_available(void)
{
return (__cpuid_has_sse2());
}
/*
* Check if SSE3 instruction set is available
*/
static inline boolean_t
zfs_sse3_available(void)
{
return (__cpuid_has_sse3());
}
/*
* Check if SSSE3 instruction set is available
*/
static inline boolean_t
zfs_ssse3_available(void)
{
return (__cpuid_has_ssse3());
}
/*
* Check if SSE4.1 instruction set is available
*/
static inline boolean_t
zfs_sse4_1_available(void)
{
return (__cpuid_has_sse4_1());
}
/*
* Check if SSE4.2 instruction set is available
*/
static inline boolean_t
zfs_sse4_2_available(void)
{
return (__cpuid_has_sse4_2());
}
/*
* Check if AVX instruction set is available
*/
static inline boolean_t
zfs_avx_available(void)
{
return (__cpuid_has_avx() && __ymm_enabled());
}
/*
* Check if AVX2 instruction set is available
*/
static inline boolean_t
zfs_avx2_available(void)
{
return (__cpuid_has_avx2() && __ymm_enabled());
}
/*
* Check if BMI1 instruction set is available
*/
static inline boolean_t
zfs_bmi1_available(void)
{
return (__cpuid_has_bmi1());
}
/*
* Check if BMI2 instruction set is available
*/
static inline boolean_t
zfs_bmi2_available(void)
{
return (__cpuid_has_bmi2());
}
/*
* Check if AES instruction set is available
*/
static inline boolean_t
zfs_aes_available(void)
{
return (__cpuid_has_aes());
}
/*
* Check if PCLMULQDQ instruction set is available
*/
static inline boolean_t
zfs_pclmulqdq_available(void)
{
return (__cpuid_has_pclmulqdq());
}
/*
* Check if MOVBE instruction is available
*/
static inline boolean_t
zfs_movbe_available(void)
{
return (__cpuid_has_movbe());
}
/*
* AVX-512 family of instruction sets:
*
* AVX512F Foundation
* AVX512CD Conflict Detection Instructions
* AVX512ER Exponential and Reciprocal Instructions
* AVX512PF Prefetch Instructions
*
* AVX512BW Byte and Word Instructions
* AVX512DQ Double-word and Quadword Instructions
* AVX512VL Vector Length Extensions
*
* AVX512IFMA Integer Fused Multiply Add (Not supported by kernel 4.4)
* AVX512VBMI Vector Byte Manipulation Instructions
*/
/*
* Check if AVX512F instruction set is available
*/
static inline boolean_t
zfs_avx512f_available(void)
{
return (__cpuid_has_avx512f() && __zmm_enabled());
}
/*
* Check if AVX512CD instruction set is available
*/
static inline boolean_t
zfs_avx512cd_available(void)
{
return (__cpuid_has_avx512cd() && __zmm_enabled());
}
/*
* Check if AVX512ER instruction set is available
*/
static inline boolean_t
zfs_avx512er_available(void)
{
return (__cpuid_has_avx512er() && __zmm_enabled());
}
/*
* Check if AVX512PF instruction set is available
*/
static inline boolean_t
zfs_avx512pf_available(void)
{
return (__cpuid_has_avx512pf() && __zmm_enabled());
}
/*
* Check if AVX512BW instruction set is available
*/
static inline boolean_t
zfs_avx512bw_available(void)
{
return (__cpuid_has_avx512bw() && __zmm_enabled());
}
/*
* Check if AVX512DQ instruction set is available
*/
static inline boolean_t
zfs_avx512dq_available(void)
{
return (__cpuid_has_avx512dq() && __zmm_enabled());
}
/*
* Check if AVX512VL instruction set is available
*/
static inline boolean_t
zfs_avx512vl_available(void)
{
return (__cpuid_has_avx512vl() && __zmm_enabled());
}
/*
* Check if AVX512IFMA instruction set is available
*/
static inline boolean_t
zfs_avx512ifma_available(void)
{
return (__cpuid_has_avx512ifma() && __zmm_enabled());
}
/*
* Check if AVX512VBMI instruction set is available
*/
static inline boolean_t
zfs_avx512vbmi_available(void)
{
return (__cpuid_has_avx512f() && __cpuid_has_avx512vbmi() &&
__zmm_enabled());
}
#elif defined(__aarch64__)
#define kfpu_allowed() 1
#define kfpu_initialize(tsk) do {} while (0)
#define kfpu_begin() do {} while (0)
#define kfpu_end() do {} while (0)
#elif defined(__powerpc__)
#define kfpu_allowed() 1
#define kfpu_initialize(tsk) do {} while (0)
#define kfpu_begin() do {} while (0)
#define kfpu_end() do {} while (0)
/*
* Check if AltiVec instruction set is available
* No easy way beyond 'altivec works' :-(
*/
#include <signal.h>
#include <setjmp.h>
#ifdef __ALTIVEC__
static jmp_buf env;
static void sigillhandler(int x)
{
longjmp(env, 1);
}
#endif
static inline boolean_t
zfs_altivec_available(void)
{
boolean_t has_altivec = B_FALSE;
#ifdef __ALTIVEC__
sighandler_t savesig;
savesig = signal(SIGILL, sigillhandler);
if (setjmp(env)) {
signal(SIGILL, savesig);
has_altivec = B_FALSE;
} else {
__asm__ __volatile__("vor 0,0,0\n" : : : "v0");
signal(SIGILL, savesig);
has_altivec = B_TRUE;
}
#endif
return (has_altivec);
}
#else
#define kfpu_allowed() 0
#define kfpu_initialize(tsk) do {} while (0)
#define kfpu_begin() do {} while (0)
#define kfpu_end() do {} while (0)
#endif
#endif /* _LIBSPL_SYS_SIMD_H */