From patchwork Thu Nov 3 04:27:28 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Elliott, Robert \(Servers\)" X-Patchwork-Id: 621145 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B9571C43219 for ; Thu, 3 Nov 2022 04:28:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229547AbiKCE2X (ORCPT ); Thu, 3 Nov 2022 00:28:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55106 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229953AbiKCE2V (ORCPT ); Thu, 3 Nov 2022 00:28:21 -0400 Received: from mx0a-002e3701.pphosted.com (mx0a-002e3701.pphosted.com [148.163.147.86]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 92EC3210; Wed, 2 Nov 2022 21:28:20 -0700 (PDT) Received: from pps.filterd (m0150242.ppops.net [127.0.0.1]) by mx0a-002e3701.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 2A338Wpm012666; Thu, 3 Nov 2022 04:28:11 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=hpe.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding; s=pps0720; bh=kDCsigLBc4RiVTNQSgXraDq+QR2Ctzc5DZfvh4IK8G0=; b=D5sARtk96vU0kMAXcZa/k38vmxhz4Nv8A8uIwRD6MLhHvWSQSkLL95eiAbbOgzDjkpQt eBDcdTZnSUlsDtlSyT5H59sB5Dmk9JUGagQwaFLxi+Jm5u/Ymp3xcaB04Rw1ioHAzslJ Nhkrtjv6eNF4CI1lVNt46v999hdb6xyTFiOXWBRcpgHWSaPPiKSOgmZxFYTEdxGFZCFs MMqeVxoPcb00+AtFlyhGebHTzKgS7+C8sxvE23+mbc9DPQE28YsMDeC2mjhJs2u9MrM3 1yxZepQwVp7ltBODjODCj7jLIOYZl+8tzHlyYmJVGm4hz7QZmnPMSC7y/ZXqCY2Ri6ZR 2w== Received: from p1lg14878.it.hpe.com (p1lg14878.it.hpe.com [16.230.97.204]) by mx0a-002e3701.pphosted.com (PPS) with ESMTPS id 3km2pfhdey-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 03 Nov 2022 04:28:11 +0000 Received: from p1lg14886.dc01.its.hpecorp.net (unknown [10.119.18.237]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by p1lg14878.it.hpe.com (Postfix) with ESMTPS id BFB22D2AE; Thu, 3 Nov 2022 04:28:10 +0000 (UTC) Received: from adevxp033-sys.us.rdlabs.hpecorp.net (unknown [16.231.227.36]) by p1lg14886.dc01.its.hpecorp.net (Postfix) with ESMTP id 4DA1180A0FF; Thu, 3 Nov 2022 04:28:10 +0000 (UTC) From: Robert Elliott To: herbert@gondor.apana.org.au, davem@davemloft.net, tim.c.chen@linux.intel.com, ap420073@gmail.com, ardb@kernel.org, Jason@zx2c4.com, David.Laight@ACULAB.COM, ebiggers@kernel.org, linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Robert Elliott Subject: [PATCH v3 05/17] crypto: x86/crc - limit FPU preemption Date: Wed, 2 Nov 2022 23:27:28 -0500 Message-Id: <20221103042740.6556-6-elliott@hpe.com> X-Mailer: git-send-email 2.37.3 In-Reply-To: <20221103042740.6556-1-elliott@hpe.com> References: <20221012215931.3896-1-elliott@hpe.com> <20221103042740.6556-1-elliott@hpe.com> MIME-Version: 1.0 X-Proofpoint-GUID: kuDi_pUWUsV-mfcQTfoU9DP58tPkJBJP X-Proofpoint-ORIG-GUID: kuDi_pUWUsV-mfcQTfoU9DP58tPkJBJP X-HPE-SCL: -1 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.895,Hydra:6.0.545,FMLib:17.11.122.1 definitions=2022-11-02_15,2022-11-02_01,2022-06-22_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 impostorscore=0 bulkscore=0 adultscore=0 priorityscore=1501 lowpriorityscore=0 malwarescore=0 mlxlogscore=999 clxscore=1015 phishscore=0 suspectscore=0 mlxscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2210170000 definitions=main-2211030031 Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org Limit the number of bytes processed between kernel_fpu_begin() and kernel_fpu_end() calls. Those functions call preempt_disable() and preempt_enable(), so the CPU core is unavailable for scheduling while running, leading to: rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: ... Fixes: 78c37d191dd6 ("crypto: crc32 - add crc32 pclmulqdq implementation and wrappers for table implementation") Fixes: 6a8ce1ef3940 ("crypto: crc32c - Optimize CRC32C calculation with PCLMULQDQ instruction") Fixes: 0b95a7f85718 ("crypto: crct10dif - Glue code to cast accelerated CRCT10DIF assembly as a crypto transform") Suggested-by: Herbert Xu Signed-off-by: Robert Elliott --- v3 use while loops and static int, simplify one of the loop structures, add algorithm-specific limits, use local stack variable in crc32 finup rather than the context pointer like update uses --- arch/x86/crypto/crc32-pclmul_asm.S | 6 +-- arch/x86/crypto/crc32-pclmul_glue.c | 27 +++++++++---- arch/x86/crypto/crc32c-intel_glue.c | 52 ++++++++++++++++++------- arch/x86/crypto/crct10dif-pclmul_glue.c | 48 +++++++++++++++++------ 4 files changed, 99 insertions(+), 34 deletions(-) diff --git a/arch/x86/crypto/crc32-pclmul_asm.S b/arch/x86/crypto/crc32-pclmul_asm.S index ca53e96996ac..9abd861636c3 100644 --- a/arch/x86/crypto/crc32-pclmul_asm.S +++ b/arch/x86/crypto/crc32-pclmul_asm.S @@ -72,15 +72,15 @@ .text /** * Calculate crc32 - * BUF - buffer (16 bytes aligned) - * LEN - sizeof buffer (16 bytes aligned), LEN should be grater than 63 + * BUF - buffer - must be 16 bytes aligned + * LEN - sizeof buffer - must be multiple of 16 bytes and greater than 63 * CRC - initial crc32 * return %eax crc32 * uint crc32_pclmul_le_16(unsigned char const *buffer, * size_t len, uint crc32) */ -SYM_FUNC_START(crc32_pclmul_le_16) /* buffer and buffer size are 16 bytes aligned */ +SYM_FUNC_START(crc32_pclmul_le_16) movdqa (BUF), %xmm1 movdqa 0x10(BUF), %xmm2 movdqa 0x20(BUF), %xmm3 diff --git a/arch/x86/crypto/crc32-pclmul_glue.c b/arch/x86/crypto/crc32-pclmul_glue.c index 98cf3b4e4c9f..df3dbc754818 100644 --- a/arch/x86/crypto/crc32-pclmul_glue.c +++ b/arch/x86/crypto/crc32-pclmul_glue.c @@ -46,6 +46,9 @@ #define SCALE_F 16L /* size of xmm register */ #define SCALE_F_MASK (SCALE_F - 1) +/* avoid kernel_fpu_begin/end scheduler/rcu stalls */ +static const unsigned int bytes_per_fpu = 655 * 1024; + u32 crc32_pclmul_le_16(unsigned char const *buffer, size_t len, u32 crc32); static u32 __attribute__((pure)) @@ -55,6 +58,9 @@ static u32 __attribute__((pure)) unsigned int iremainder; unsigned int prealign; + BUILD_BUG_ON(bytes_per_fpu < PCLMUL_MIN_LEN); + BUILD_BUG_ON(bytes_per_fpu & SCALE_F_MASK); + if (len < PCLMUL_MIN_LEN + SCALE_F_MASK || !crypto_simd_usable()) return crc32_le(crc, p, len); @@ -70,12 +76,19 @@ static u32 __attribute__((pure)) iquotient = len & (~SCALE_F_MASK); iremainder = len & SCALE_F_MASK; - kernel_fpu_begin(); - crc = crc32_pclmul_le_16(p, iquotient, crc); - kernel_fpu_end(); + while (iquotient >= PCLMUL_MIN_LEN) { + unsigned int chunk = min(iquotient, bytes_per_fpu); + + kernel_fpu_begin(); + crc = crc32_pclmul_le_16(p, chunk, crc); + kernel_fpu_end(); + + iquotient -= chunk; + p += chunk; + } - if (iremainder) - crc = crc32_le(crc, p + iquotient, iremainder); + if (iquotient || iremainder) + crc = crc32_le(crc, p, iquotient + iremainder); return crc; } @@ -120,8 +133,8 @@ static int crc32_pclmul_update(struct shash_desc *desc, const u8 *data, } /* No final XOR 0xFFFFFFFF, like crc32_le */ -static int __crc32_pclmul_finup(u32 *crcp, const u8 *data, unsigned int len, - u8 *out) +static int __crc32_pclmul_finup(const u32 *crcp, const u8 *data, + unsigned int len, u8 *out) { *(__le32 *)out = cpu_to_le32(crc32_pclmul_le(*crcp, data, len)); return 0; diff --git a/arch/x86/crypto/crc32c-intel_glue.c b/arch/x86/crypto/crc32c-intel_glue.c index feccb5254c7e..f08ed68ec93d 100644 --- a/arch/x86/crypto/crc32c-intel_glue.c +++ b/arch/x86/crypto/crc32c-intel_glue.c @@ -45,7 +45,10 @@ asmlinkage unsigned int crc_pcl(const u8 *buffer, int len, unsigned int crc_init); #endif /* CONFIG_X86_64 */ -static u32 crc32c_intel_le_hw_byte(u32 crc, unsigned char const *data, size_t length) +/* avoid kernel_fpu_begin/end scheduler/rcu stalls */ +static const unsigned int bytes_per_fpu = 868 * 1024; + +static u32 crc32c_intel_le_hw_byte(u32 crc, const unsigned char *data, size_t length) { while (length--) { asm("crc32b %1, %0" @@ -56,7 +59,7 @@ static u32 crc32c_intel_le_hw_byte(u32 crc, unsigned char const *data, size_t le return crc; } -static u32 __pure crc32c_intel_le_hw(u32 crc, unsigned char const *p, size_t len) +static u32 __pure crc32c_intel_le_hw(u32 crc, const unsigned char *p, size_t len) { unsigned int iquotient = len / SCALE_F; unsigned int iremainder = len % SCALE_F; @@ -110,8 +113,8 @@ static int crc32c_intel_update(struct shash_desc *desc, const u8 *data, return 0; } -static int __crc32c_intel_finup(u32 *crcp, const u8 *data, unsigned int len, - u8 *out) +static int __crc32c_intel_finup(const u32 *crcp, const u8 *data, + unsigned int len, u8 *out) { *(__le32 *)out = ~cpu_to_le32(crc32c_intel_le_hw(*crcp, data, len)); return 0; @@ -153,29 +156,52 @@ static int crc32c_pcl_intel_update(struct shash_desc *desc, const u8 *data, { u32 *crcp = shash_desc_ctx(desc); + BUILD_BUG_ON(bytes_per_fpu < CRC32C_PCL_BREAKEVEN); + BUILD_BUG_ON(bytes_per_fpu % SCALE_F); + /* * use faster PCL version if datasize is large enough to * overcome kernel fpu state save/restore overhead */ if (len >= CRC32C_PCL_BREAKEVEN && crypto_simd_usable()) { - kernel_fpu_begin(); - *crcp = crc_pcl(data, len, *crcp); - kernel_fpu_end(); + while (len) { + unsigned int chunk = min(len, bytes_per_fpu); + + kernel_fpu_begin(); + *crcp = crc_pcl(data, chunk, *crcp); + kernel_fpu_end(); + + len -= chunk; + data += chunk; + } } else *crcp = crc32c_intel_le_hw(*crcp, data, len); return 0; } -static int __crc32c_pcl_intel_finup(u32 *crcp, const u8 *data, unsigned int len, - u8 *out) +static int __crc32c_pcl_intel_finup(const u32 *crcp, const u8 *data, + unsigned int len, u8 *out) { + u32 crc = *crcp; + + BUILD_BUG_ON(bytes_per_fpu < CRC32C_PCL_BREAKEVEN); + BUILD_BUG_ON(bytes_per_fpu % SCALE_F); + if (len >= CRC32C_PCL_BREAKEVEN && crypto_simd_usable()) { - kernel_fpu_begin(); - *(__le32 *)out = ~cpu_to_le32(crc_pcl(data, len, *crcp)); - kernel_fpu_end(); + while (len) { + unsigned int chunk = min(len, bytes_per_fpu); + + kernel_fpu_begin(); + crc = crc_pcl(data, chunk, crc); + kernel_fpu_end(); + + len -= chunk; + data += chunk; + } + *(__le32 *)out = ~cpu_to_le32(crc); } else *(__le32 *)out = - ~cpu_to_le32(crc32c_intel_le_hw(*crcp, data, len)); + ~cpu_to_le32(crc32c_intel_le_hw(crc, data, len)); return 0; } diff --git a/arch/x86/crypto/crct10dif-pclmul_glue.c b/arch/x86/crypto/crct10dif-pclmul_glue.c index 71291d5af9f4..4f6b8c727d88 100644 --- a/arch/x86/crypto/crct10dif-pclmul_glue.c +++ b/arch/x86/crypto/crct10dif-pclmul_glue.c @@ -34,6 +34,11 @@ #include #include +#define PCLMUL_MIN_LEN 16U /* minimum size of buffer for crc_t10dif_pcl */ + +/* avoid kernel_fpu_begin/end scheduler/rcu stalls */ +static const unsigned int bytes_per_fpu = 614 * 1024; + asmlinkage u16 crc_t10dif_pcl(u16 init_crc, const u8 *buf, size_t len); struct chksum_desc_ctx { @@ -54,11 +59,21 @@ static int chksum_update(struct shash_desc *desc, const u8 *data, { struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); - if (length >= 16 && crypto_simd_usable()) { - kernel_fpu_begin(); - ctx->crc = crc_t10dif_pcl(ctx->crc, data, length); - kernel_fpu_end(); - } else + BUILD_BUG_ON(bytes_per_fpu < PCLMUL_MIN_LEN); + + if (length >= PCLMUL_MIN_LEN && crypto_simd_usable()) { + while (length >= PCLMUL_MIN_LEN) { + unsigned int chunk = min(length, bytes_per_fpu); + + kernel_fpu_begin(); + ctx->crc = crc_t10dif_pcl(ctx->crc, data, chunk); + kernel_fpu_end(); + + length -= chunk; + data += chunk; + } + } + if (length) ctx->crc = crc_t10dif_generic(ctx->crc, data, length); return 0; } @@ -73,12 +88,23 @@ static int chksum_final(struct shash_desc *desc, u8 *out) static int __chksum_finup(__u16 crc, const u8 *data, unsigned int len, u8 *out) { - if (len >= 16 && crypto_simd_usable()) { - kernel_fpu_begin(); - *(__u16 *)out = crc_t10dif_pcl(crc, data, len); - kernel_fpu_end(); - } else - *(__u16 *)out = crc_t10dif_generic(crc, data, len); + BUILD_BUG_ON(bytes_per_fpu < PCLMUL_MIN_LEN); + + if (len >= PCLMUL_MIN_LEN && crypto_simd_usable()) { + while (len >= PCLMUL_MIN_LEN) { + unsigned int chunk = min(len, bytes_per_fpu); + + kernel_fpu_begin(); + crc = crc_t10dif_pcl(crc, data, chunk); + kernel_fpu_end(); + + len -= chunk; + data += chunk; + } + } + if (len) + crc = crc_t10dif_generic(crc, data, len); + *(__u16 *)out = crc; return 0; }