From be2830b15b60011845ad701076511e8b93b2fd76 Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Fri, 16 Nov 2018 17:26:23 -0800 Subject: [PATCH] crypto: arm/chacha20 - limit the preemption-disabled section To improve responsivesess, disable preemption for each step of the walk (which is at most PAGE_SIZE) rather than for the entire encryption/decryption operation. Suggested-by: Ard Biesheuvel Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu --- arch/arm/crypto/chacha20-neon-glue.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/arm/crypto/chacha20-neon-glue.c b/arch/arm/crypto/chacha20-neon-glue.c index 7386eb1..2bc035c 100644 --- a/arch/arm/crypto/chacha20-neon-glue.c +++ b/arch/arm/crypto/chacha20-neon-glue.c @@ -68,22 +68,22 @@ static int chacha20_neon(struct skcipher_request *req) if (req->cryptlen <= CHACHA_BLOCK_SIZE || !may_use_simd()) return crypto_chacha_crypt(req); - err = skcipher_walk_virt(&walk, req, true); + err = skcipher_walk_virt(&walk, req, false); crypto_chacha_init(state, ctx, walk.iv); - kernel_neon_begin(); while (walk.nbytes > 0) { unsigned int nbytes = walk.nbytes; if (nbytes < walk.total) nbytes = round_down(nbytes, walk.stride); + kernel_neon_begin(); chacha20_doneon(state, walk.dst.virt.addr, walk.src.virt.addr, nbytes); + kernel_neon_end(); err = skcipher_walk_done(&walk, walk.nbytes - nbytes); } - kernel_neon_end(); return err; } -- 2.7.4