Commit 7df8d164 authored by Ard Biesheuvel's avatar Ard Biesheuvel Committed by Herbert Xu
Browse files

crypto: arm64/sha1-ce - yield NEON after every block of input 



Avoid excessive scheduling delays under a preemptible kernel by
yielding the NEON after every block of input.

Signed-off-by: default avatarArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
parent 158b52ff

arch/arm64/crypto/sha1-ce-core.S

+29 −13
Original line number Diff line number Diff line
@@ -69,30 +69,36 @@ 
	 *			  int blocks)

	 */

ENTRY(sha1_ce_transform)

	frame_push	3



	mov		x19, x0

	mov		x20, x1

	mov		x21, x2



	/* load round constants */

	loadrc		k0.4s, 0x5a827999, w6

0:	loadrc		k0.4s, 0x5a827999, w6

	loadrc		k1.4s, 0x6ed9eba1, w6

	loadrc		k2.4s, 0x8f1bbcdc, w6

	loadrc		k3.4s, 0xca62c1d6, w6



	/* load state */

	ld1		{dgav.4s}, [x0]

	ldr		dgb, [x0, #16]

	ld1		{dgav.4s}, [x19]

	ldr		dgb, [x19, #16]



	/* load sha1_ce_state::finalize */

	ldr_l		w4, sha1_ce_offsetof_finalize, x4

	ldr		w4, [x0, x4]

	ldr		w4, [x19, x4]



	/* load input */

0:	ld1		{v8.4s-v11.4s}, [x1], #64

	sub		w2, w2, #1

1:	ld1		{v8.4s-v11.4s}, [x20], #64

	sub		w21, w21, #1



CPU_LE(	rev32		v8.16b, v8.16b		)

CPU_LE(	rev32		v9.16b, v9.16b		)

CPU_LE(	rev32		v10.16b, v10.16b	)

CPU_LE(	rev32		v11.16b, v11.16b	)



1:	add		t0.4s, v8.4s, k0.4s

2:	add		t0.4s, v8.4s, k0.4s

	mov		dg0v.16b, dgav.16b



	add_update	c, ev, k0,  8,  9, 10, 11, dgb
@@ -123,16 +129,25 @@ CPU_LE( rev32 v11.16b, v11.16b ) 
	add		dgbv.2s, dgbv.2s, dg1v.2s

	add		dgav.4s, dgav.4s, dg0v.4s



	cbnz		w2, 0b

	cbz		w21, 3f



	if_will_cond_yield_neon

	st1		{dgav.4s}, [x19]

	str		dgb, [x19, #16]

	do_cond_yield_neon

	b		0b

	endif_yield_neon



	b		1b



	/*

	 * Final block: add padding and total bit count.

	 * Skip if the input size was not a round multiple of the block size,

	 * the padding is handled by the C code in that case.

	 */

	cbz		x4, 3f

3:	cbz		x4, 4f

	ldr_l		w4, sha1_ce_offsetof_count, x4

	ldr		x4, [x0, x4]

	ldr		x4, [x19, x4]

	movi		v9.2d, #0

	mov		x8, #0x80000000

	movi		v10.2d, #0
@@ -141,10 +156,11 @@ CPU_LE( rev32 v11.16b, v11.16b ) 
	mov		x4, #0

	mov		v11.d[0], xzr

	mov		v11.d[1], x7

	b		1b

	b		2b



	/* store new state */

3:	st1		{dgav.4s}, [x0]

	str		dgb, [x0, #16]

4:	st1		{dgav.4s}, [x19]

	str		dgb, [x19, #16]

	frame_pop

	ret

ENDPROC(sha1_ce_transform)