x86: remove always-defined CONFIG_AS_AVX

CONFIG_AS_AVX was introduced by commit ea4d26ae ("raid5: add AVX
optimized RAID5 checksumming").

We raise the minimal supported binutils version from time to time.
The last bump was commit 1fb12b35 ("kbuild: Raise the minimum
required binutils version to 2.21").

I confirmed the code in $(call as-instr,...) can be assembled by the
binutils 2.21 assembler and also by LLVM integrated assembler.

Remove CONFIG_AS_AVX, which is always defined.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Jason A. Donenfeld <Jason@zx2c4.com>
Acked-by: Ingo Molnar <mingo@kernel.org>

arch/x86/Makefile

@@ -178,15 +178,14 @@ ifeq ($(ACCUMULATE_OUTGOING_ARGS), 1)
 endif
 
 # does binutils support specific instructions?
-avx_instr := $(call as-instr,vxorps %ymm0$(comma)%ymm1$(comma)%ymm2,-DCONFIG_AS_AVX=1)
 avx2_instr :=$(call as-instr,vpbroadcastb %xmm0$(comma)%ymm1,-DCONFIG_AS_AVX2=1)
 avx512_instr :=$(call as-instr,vpmovm2b %k1$(comma)%zmm5,-DCONFIG_AS_AVX512=1)
 sha1_ni_instr :=$(call as-instr,sha1msg1 %xmm0$(comma)%xmm1,-DCONFIG_AS_SHA1_NI=1)
 sha256_ni_instr :=$(call as-instr,sha256msg1 %xmm0$(comma)%xmm1,-DCONFIG_AS_SHA256_NI=1)
 adx_instr := $(call as-instr,adox %r10$(comma)%r10,-DCONFIG_AS_ADX=1)
 
-KBUILD_AFLAGS += $(avx_instr) $(avx2_instr) $(avx512_instr) $(sha1_ni_instr) $(sha256_ni_instr) $(adx_instr)
-KBUILD_CFLAGS += $(avx_instr) $(avx2_instr) $(avx512_instr) $(sha1_ni_instr) $(sha256_ni_instr) $(adx_instr)
+KBUILD_AFLAGS += $(avx2_instr) $(avx512_instr) $(sha1_ni_instr) $(sha256_ni_instr) $(adx_instr)
+KBUILD_CFLAGS += $(avx2_instr) $(avx512_instr) $(sha1_ni_instr) $(sha256_ni_instr) $(adx_instr)
 
 KBUILD_LDFLAGS := -m elf_$(UTS_MACHINE)
 

arch/x86/crypto/Makefile

@@ -5,7 +5,6 @@
 
 OBJECT_FILES_NON_STANDARD := y
 
-avx_supported := $(call as-instr,vpxor %xmm0$(comma)%xmm0$(comma)%xmm0,yes,no)
 avx2_supported := $(call as-instr,vpgatherdd %ymm0$(comma)(%eax$(comma)%ymm1\
 				$(comma)4)$(comma)%ymm2,yes,no)
 avx512_supported :=$(call as-instr,vpmovm2b %k1$(comma)%zmm5,yes,no)
@@ -47,15 +46,12 @@ ifeq ($(adx_supported),yes)
 endif
 
 # These modules require assembler to support AVX.
-ifeq ($(avx_supported),yes)
-	obj-$(CONFIG_CRYPTO_CAMELLIA_AESNI_AVX_X86_64) += \
-						camellia-aesni-avx-x86_64.o
-	obj-$(CONFIG_CRYPTO_CAST5_AVX_X86_64) += cast5-avx-x86_64.o
-	obj-$(CONFIG_CRYPTO_CAST6_AVX_X86_64) += cast6-avx-x86_64.o
-	obj-$(CONFIG_CRYPTO_TWOFISH_AVX_X86_64) += twofish-avx-x86_64.o
-	obj-$(CONFIG_CRYPTO_SERPENT_AVX_X86_64) += serpent-avx-x86_64.o
-	obj-$(CONFIG_CRYPTO_BLAKE2S_X86) += blake2s-x86_64.o
-endif
+obj-$(CONFIG_CRYPTO_CAMELLIA_AESNI_AVX_X86_64) += camellia-aesni-avx-x86_64.o
+obj-$(CONFIG_CRYPTO_CAST5_AVX_X86_64) += cast5-avx-x86_64.o
+obj-$(CONFIG_CRYPTO_CAST6_AVX_X86_64) += cast6-avx-x86_64.o
+obj-$(CONFIG_CRYPTO_TWOFISH_AVX_X86_64) += twofish-avx-x86_64.o
+obj-$(CONFIG_CRYPTO_SERPENT_AVX_X86_64) += serpent-avx-x86_64.o
+obj-$(CONFIG_CRYPTO_BLAKE2S_X86) += blake2s-x86_64.o
 
 # These modules require assembler to support AVX2.
 ifeq ($(avx2_supported),yes)
@@ -83,16 +79,12 @@ ifneq ($(CONFIG_CRYPTO_POLY1305_X86_64),)
 targets += poly1305-x86_64-cryptogams.S
 endif
 
-ifeq ($(avx_supported),yes)
-	camellia-aesni-avx-x86_64-y := camellia-aesni-avx-asm_64.o \
-					camellia_aesni_avx_glue.o
-	cast5-avx-x86_64-y := cast5-avx-x86_64-asm_64.o cast5_avx_glue.o
-	cast6-avx-x86_64-y := cast6-avx-x86_64-asm_64.o cast6_avx_glue.o
-	twofish-avx-x86_64-y := twofish-avx-x86_64-asm_64.o \
-				twofish_avx_glue.o
-	serpent-avx-x86_64-y := serpent-avx-x86_64-asm_64.o \
-				serpent_avx_glue.o
-endif
+camellia-aesni-avx-x86_64-y := camellia-aesni-avx-asm_64.o \
+				camellia_aesni_avx_glue.o
+cast5-avx-x86_64-y := cast5-avx-x86_64-asm_64.o cast5_avx_glue.o
+cast6-avx-x86_64-y := cast6-avx-x86_64-asm_64.o cast6_avx_glue.o
+twofish-avx-x86_64-y := twofish-avx-x86_64-asm_64.o twofish_avx_glue.o
+serpent-avx-x86_64-y := serpent-avx-x86_64-asm_64.o serpent_avx_glue.o
 
 ifeq ($(avx2_supported),yes)
 	camellia-aesni-avx2-y := camellia-aesni-avx2-asm_64.o camellia_aesni_avx2_glue.o

arch/x86/crypto/aesni-intel_avx-x86_64.S

@@ -886,7 +886,6 @@ _less_than_8_bytes_left_\@:
 _partial_block_done_\@:
 .endm # PARTIAL_BLOCK
 
-#ifdef CONFIG_AS_AVX
 ###############################################################################
 # GHASH_MUL MACRO to implement: Data*HashKey mod (128,127,126,121,0)
 # Input: A and B (128-bits each, bit-reflected)
@@ -1869,8 +1868,6 @@ key_256_finalize:
         ret
 SYM_FUNC_END(aesni_gcm_finalize_avx_gen2)
 
-#endif /* CONFIG_AS_AVX */
-
 #ifdef CONFIG_AS_AVX2
 ###############################################################################
 # GHASH_MUL MACRO to implement: Data*HashKey mod (128,127,126,121,0)

arch/x86/crypto/aesni-intel_glue.c

@@ -185,7 +185,6 @@ static const struct aesni_gcm_tfm_s aesni_gcm_tfm_sse = {
 	.finalize = &aesni_gcm_finalize,
 };
 
-#ifdef CONFIG_AS_AVX
 asmlinkage void aes_ctr_enc_128_avx_by8(const u8 *in, u8 *iv,
 		void *keys, u8 *out, unsigned int num_bytes);
 asmlinkage void aes_ctr_enc_192_avx_by8(const u8 *in, u8 *iv,
@@ -234,8 +233,6 @@ static const struct aesni_gcm_tfm_s aesni_gcm_tfm_avx_gen2 = {
 	.finalize = &aesni_gcm_finalize_avx_gen2,
 };
 
-#endif
-
 #ifdef CONFIG_AS_AVX2
 /*
  * asmlinkage void aesni_gcm_init_avx_gen4()
@@ -476,7 +473,6 @@ static void ctr_crypt_final(struct crypto_aes_ctx *ctx,
 	crypto_inc(ctrblk, AES_BLOCK_SIZE);
 }
 
-#ifdef CONFIG_AS_AVX
 static void aesni_ctr_enc_avx_tfm(struct crypto_aes_ctx *ctx, u8 *out,
 			      const u8 *in, unsigned int len, u8 *iv)
 {
@@ -493,7 +489,6 @@ static void aesni_ctr_enc_avx_tfm(struct crypto_aes_ctx *ctx, u8 *out,
 	else
 		aes_ctr_enc_256_avx_by8(in, iv, (void *)ctx, out, len);
 }
-#endif
 
 static int ctr_crypt(struct skcipher_request *req)
 {
@@ -715,10 +710,8 @@ static int gcmaes_crypt_by_sg(bool enc, struct aead_request *req,
 	if (left < AVX_GEN4_OPTSIZE && gcm_tfm == &aesni_gcm_tfm_avx_gen4)
 		gcm_tfm = &aesni_gcm_tfm_avx_gen2;
 #endif
-#ifdef CONFIG_AS_AVX
 	if (left < AVX_GEN2_OPTSIZE && gcm_tfm == &aesni_gcm_tfm_avx_gen2)
 		gcm_tfm = &aesni_gcm_tfm_sse;
-#endif
 
 	/* Linearize assoc, if not already linear */
 	if (req->src->length >= assoclen && req->src->length &&
@@ -1082,24 +1075,19 @@ static int __init aesni_init(void)
 		aesni_gcm_tfm = &aesni_gcm_tfm_avx_gen4;
 	} else
 #endif
-#ifdef CONFIG_AS_AVX
 	if (boot_cpu_has(X86_FEATURE_AVX)) {
 		pr_info("AVX version of gcm_enc/dec engaged.\n");
 		aesni_gcm_tfm = &aesni_gcm_tfm_avx_gen2;
-	} else
-#endif
-	{
+	} else {
 		pr_info("SSE version of gcm_enc/dec engaged.\n");
 		aesni_gcm_tfm = &aesni_gcm_tfm_sse;
 	}
 	aesni_ctr_enc_tfm = aesni_ctr_enc;
-#ifdef CONFIG_AS_AVX
 	if (boot_cpu_has(X86_FEATURE_AVX)) {
 		/* optimize performance of ctr mode encryption transform */
 		aesni_ctr_enc_tfm = aesni_ctr_enc_avx_tfm;
 		pr_info("AES CTR mode by8 optimization enabled\n");
 	}
-#endif
 #endif
 
 	err = crypto_register_alg(&aesni_cipher_alg);

arch/x86/crypto/poly1305-x86_64-cryptogams.pl

@@ -404,10 +404,6 @@ ___
 &end_function("poly1305_emit_x86_64");
 if ($avx) {
 
-if($kernel) {
-	$code .= "#ifdef CONFIG_AS_AVX\n";
-}
-
 ########################################################################
 # Layout of opaque area is following.
 #
@@ -1516,10 +1512,6 @@ $code.=<<___;
 ___
 &end_function("poly1305_emit_avx");
 
-if ($kernel) {
-	$code .= "#endif\n";
-}
-
 if ($avx>1) {
 
 if ($kernel) {

arch/x86/crypto/poly1305_glue.c

@@ -94,7 +94,7 @@ static void poly1305_simd_blocks(void *ctx, const u8 *inp, size_t len,
 	BUILD_BUG_ON(PAGE_SIZE < POLY1305_BLOCK_SIZE ||
 		     PAGE_SIZE % POLY1305_BLOCK_SIZE);
 
-	if (!IS_ENABLED(CONFIG_AS_AVX) || !static_branch_likely(&poly1305_use_avx) ||
+	if (!static_branch_likely(&poly1305_use_avx) ||
 	    (len < (POLY1305_BLOCK_SIZE * 18) && !state->is_base2_26) ||
 	    !crypto_simd_usable()) {
 		convert_to_base2_64(ctx);
@@ -123,7 +123,7 @@ static void poly1305_simd_blocks(void *ctx, const u8 *inp, size_t len,
 static void poly1305_simd_emit(void *ctx, u8 mac[POLY1305_DIGEST_SIZE],
 			       const u32 nonce[4])
 {
-	if (!IS_ENABLED(CONFIG_AS_AVX) || !static_branch_likely(&poly1305_use_avx))
+	if (!static_branch_likely(&poly1305_use_avx))
 		poly1305_emit_x86_64(ctx, mac, nonce);
 	else
 		poly1305_emit_avx(ctx, mac, nonce);
@@ -261,7 +261,7 @@ static struct shash_alg alg = {
 
 static int __init poly1305_simd_mod_init(void)
 {
-	if (IS_ENABLED(CONFIG_AS_AVX) && boot_cpu_has(X86_FEATURE_AVX) &&
+	if (boot_cpu_has(X86_FEATURE_AVX) &&
 	    cpu_has_xfeatures(XFEATURE_MASK_SSE | XFEATURE_MASK_YMM, NULL))
 		static_branch_enable(&poly1305_use_avx);
 	if (IS_ENABLED(CONFIG_AS_AVX2) && boot_cpu_has(X86_FEATURE_AVX) &&

arch/x86/crypto/sha1_ssse3_asm.S

@@ -467,8 +467,6 @@ W_PRECALC_SSSE3
  */
 SHA1_VECTOR_ASM     sha1_transform_ssse3
 
-#ifdef CONFIG_AS_AVX
-
 .macro W_PRECALC_AVX
 
 .purgem W_PRECALC_00_15
@@ -553,5 +551,3 @@ W_PRECALC_AVX
  *				       const u8 *data, int blocks);
  */
 SHA1_VECTOR_ASM     sha1_transform_avx
-
-#endif

arch/x86/crypto/sha1_ssse3_glue.c

@@ -114,7 +114,6 @@ static void unregister_sha1_ssse3(void)
 		crypto_unregister_shash(&sha1_ssse3_alg);
 }
 
-#ifdef CONFIG_AS_AVX
 asmlinkage void sha1_transform_avx(struct sha1_state *state,
 				   const u8 *data, int blocks);
 
@@ -175,13 +174,7 @@ static void unregister_sha1_avx(void)
 		crypto_unregister_shash(&sha1_avx_alg);
 }
 
-#else  /* CONFIG_AS_AVX */
-static inline int register_sha1_avx(void) { return 0; }
-static inline void unregister_sha1_avx(void) { }
-#endif /* CONFIG_AS_AVX */
-
-
-#if defined(CONFIG_AS_AVX2) && (CONFIG_AS_AVX)
+#if defined(CONFIG_AS_AVX2)
 #define SHA1_AVX2_BLOCK_OPTSIZE	4	/* optimal 4*64 bytes of SHA1 blocks */
 
 asmlinkage void sha1_transform_avx2(struct sha1_state *state,

arch/x86/crypto/sha256-avx-asm.S

@@ -47,7 +47,6 @@
 # This code schedules 1 block at a time, with 4 lanes per block
 ########################################################################
 
-#ifdef CONFIG_AS_AVX
 #include <linux/linkage.h>
 
 ## assume buffers not aligned
@@ -498,5 +497,3 @@ _SHUF_00BA:
 # shuffle xDxC -> DC00
 _SHUF_DC00:
 	.octa 0x0b0a090803020100FFFFFFFFFFFFFFFF
-
-#endif

arch/x86/crypto/sha256_ssse3_glue.c

@@ -144,7 +144,6 @@ static void unregister_sha256_ssse3(void)
 				ARRAY_SIZE(sha256_ssse3_algs));
 }
 
-#ifdef CONFIG_AS_AVX
 asmlinkage void sha256_transform_avx(struct sha256_state *state,
 				     const u8 *data, int blocks);
 
@@ -221,12 +220,7 @@ static void unregister_sha256_avx(void)
 				ARRAY_SIZE(sha256_avx_algs));
 }
 
-#else
-static inline int register_sha256_avx(void) { return 0; }
-static inline void unregister_sha256_avx(void) { }
-#endif
-
-#if defined(CONFIG_AS_AVX2) && defined(CONFIG_AS_AVX)
+#if defined(CONFIG_AS_AVX2)
 asmlinkage void sha256_transform_rorx(struct sha256_state *state,
 				      const u8 *data, int blocks);
 

arch/x86/crypto/sha512-avx-asm.S

@@ -47,7 +47,6 @@
 #
 ########################################################################
 
-#ifdef CONFIG_AS_AVX
 #include <linux/linkage.h>
 
 .text
@@ -424,4 +423,3 @@ K512:
 	.quad 0x3c9ebe0a15c9bebc,0x431d67c49c100d4c
 	.quad 0x4cc5d4becb3e42b6,0x597f299cfc657e2a
 	.quad 0x5fcb6fab3ad6faec,0x6c44198c4a475817
-#endif

arch/x86/crypto/sha512_ssse3_glue.c

@@ -142,7 +142,6 @@ static void unregister_sha512_ssse3(void)
 			ARRAY_SIZE(sha512_ssse3_algs));
 }
 
-#ifdef CONFIG_AS_AVX
 asmlinkage void sha512_transform_avx(struct sha512_state *state,
 				     const u8 *data, int blocks);
 static bool avx_usable(void)
@@ -218,12 +217,8 @@ static void unregister_sha512_avx(void)
 		crypto_unregister_shashes(sha512_avx_algs,
 			ARRAY_SIZE(sha512_avx_algs));
 }
-#else
-static inline int register_sha512_avx(void) { return 0; }
-static inline void unregister_sha512_avx(void) { }
-#endif
 
-#if defined(CONFIG_AS_AVX2) && defined(CONFIG_AS_AVX)
+#if defined(CONFIG_AS_AVX2)
 asmlinkage void sha512_transform_rorx(struct sha512_state *state,
 				      const u8 *data, int blocks);
 

arch/x86/include/asm/xor_avx.h

@@ -11,8 +11,6 @@
  * Based on Ingo Molnar and Zach Brown's respective MMX and SSE routines
  */
 
-#ifdef CONFIG_AS_AVX
-
 #include <linux/compiler.h>
 #include <asm/fpu/api.h>
 
@@ -170,11 +168,4 @@ do { \
 #define AVX_SELECT(FASTEST) \
 	(boot_cpu_has(X86_FEATURE_AVX) && boot_cpu_has(X86_FEATURE_OSXSAVE) ? &xor_block_avx : FASTEST)
 
-#else
-
-#define AVX_XOR_SPEED {}
-
-#define AVX_SELECT(FASTEST) (FASTEST)
-
-#endif
 #endif