Patch Detail

HTTP 200 OK
Allow: GET, PUT, PATCH, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

{
    "id": 1313,
    "url": "https://patches.dpdk.org/api/patches/1313/?format=api",
    "web_url": "https://patches.dpdk.org/project/dpdk/patch/1416160760-16087-4-git-send-email-e_zhumabekov@sts.kz/",
    "project": {
        "id": 1,
        "url": "https://patches.dpdk.org/api/projects/1/?format=api",
        "name": "DPDK",
        "link_name": "dpdk",
        "list_id": "dev.dpdk.org",
        "list_email": "dev@dpdk.org",
        "web_url": "http://core.dpdk.org",
        "scm_url": "git://dpdk.org/dpdk",
        "webscm_url": "http://git.dpdk.org/dpdk",
        "list_archive_url": "https://inbox.dpdk.org/dev",
        "list_archive_url_format": "https://inbox.dpdk.org/dev/{}",
        "commit_url_format": ""
    },
    "msgid": "<1416160760-16087-4-git-send-email-e_zhumabekov@sts.kz>",
    "list_archive_url": "https://inbox.dpdk.org/dev/1416160760-16087-4-git-send-email-e_zhumabekov@sts.kz",
    "date": "2014-11-16T17:59:19",
    "name": "[dpdk-dev,v2,3/4] hash: add fallback to software CRC32 implementation",
    "commit_ref": null,
    "pull_url": null,
    "state": "superseded",
    "archived": true,
    "hash": "939f1d8f2a4e02e34d3ed0a51557849674dc4968",
    "submitter": {
        "id": 36,
        "url": "https://patches.dpdk.org/api/people/36/?format=api",
        "name": "Yerden Zhumabekov",
        "email": "e_zhumabekov@sts.kz"
    },
    "delegate": null,
    "mbox": "https://patches.dpdk.org/project/dpdk/patch/1416160760-16087-4-git-send-email-e_zhumabekov@sts.kz/mbox/",
    "series": [],
    "comments": "https://patches.dpdk.org/api/patches/1313/comments/",
    "check": "pending",
    "checks": "https://patches.dpdk.org/api/patches/1313/checks/",
    "tags": {},
    "related": [],
    "headers": {
        "Return-Path": "<dev-bounces@dpdk.org>",
        "X-Original-To": "patchwork@dpdk.org",
        "Delivered-To": "patchwork@dpdk.org",
        "Received": [
            "from [92.243.14.124] (localhost [IPv6:::1])\n\tby dpdk.org (Postfix) with ESMTP id 5167E7FE5;\n\tSun, 16 Nov 2014 18:48:51 +0100 (CET)",
            "from mgw.gov.kz (mgw.gov.kz [89.218.88.242])\n\tby dpdk.org (Postfix) with ESMTP id 07B687FB4\n\tfor <dev@dpdk.org>; Sun, 16 Nov 2014 18:48:47 +0100 (CET)",
            "from mgw.gov.kz (mx.ctsat.kz [178.89.4.95])\n\tby mgw.gov.kz  with ESMTP id sAGHww2p029789-sAGHww2r029789\n\t(version=TLSv1.0 cipher=AES128-SHA bits=128 verify=NO);\n\tSun, 16 Nov 2014 23:58:58 +0600",
            "from EXCASHUB2.rgp.local (192.168.40.53) by EdgeForefront.rgp.local\n\t(192.168.40.59) with Microsoft SMTP Server (TLS) id 14.2.247.3;\n\tSun, 16 Nov 2014 23:58:48 +0600",
            "from r220.rgp.local (192.168.59.10) by excashub2.rgp.local\n\t(192.168.40.48) with Microsoft SMTP Server (TLS) id 14.2.247.3;\n\tSun, 16 Nov 2014 23:59:03 +0600"
        ],
        "From": "Yerden Zhumabekov <e_zhumabekov@sts.kz>",
        "To": "<dev@dpdk.org>",
        "Date": "Sun, 16 Nov 2014 23:59:19 +0600",
        "Message-ID": "<1416160760-16087-4-git-send-email-e_zhumabekov@sts.kz>",
        "X-Mailer": "git-send-email 1.7.9.5",
        "In-Reply-To": "<1409724351-23786-1-git-send-email-e_zhumabekov@sts.kz>",
        "References": "<1409724351-23786-1-git-send-email-e_zhumabekov@sts.kz>",
        "MIME-Version": "1.0",
        "Content-Type": "text/plain",
        "X-Originating-IP": "[192.168.59.10]",
        "X-FEAS-SYSTEM-WL": "e_zhumabekov@sts.kz",
        "Subject": "[dpdk-dev] [PATCH v2 3/4] hash: add fallback to software CRC32\n\timplementation",
        "X-BeenThere": "dev@dpdk.org",
        "X-Mailman-Version": "2.1.15",
        "Precedence": "list",
        "List-Id": "patches and discussions about DPDK <dev.dpdk.org>",
        "List-Unsubscribe": "<http://dpdk.org/ml/options/dev>,\n\t<mailto:dev-request@dpdk.org?subject=unsubscribe>",
        "List-Archive": "<http://dpdk.org/ml/archives/dev/>",
        "List-Post": "<mailto:dev@dpdk.org>",
        "List-Help": "<mailto:dev-request@dpdk.org?subject=help>",
        "List-Subscribe": "<http://dpdk.org/ml/listinfo/dev>,\n\t<mailto:dev-request@dpdk.org?subject=subscribe>",
        "Errors-To": "dev-bounces@dpdk.org",
        "Sender": "\"dev\" <dev-bounces@dpdk.org>"
    },
    "content": "Initially, SSE4.2 support is detected via CPUID instruction.\n\nAdded rte_hash_crc_set_alg() function to detect and set CRC32\nimplementation if necessary. SSE4.2 is allowed by default. If it's\nnot available, fall back to sw implementation.\n\nSigned-off-by: Yerden Zhumabekov <e_zhumabekov@sts.kz>\n---\n lib/librte_hash/rte_hash_crc.h |   60 ++++++++++++++++++++++++++++++++++++++--\n 1 file changed, 58 insertions(+), 2 deletions(-)",
    "diff": "diff --git a/lib/librte_hash/rte_hash_crc.h b/lib/librte_hash/rte_hash_crc.h\nindex 74e2d92..178b162 100644\n--- a/lib/librte_hash/rte_hash_crc.h\n+++ b/lib/librte_hash/rte_hash_crc.h\n@@ -45,7 +45,11 @@ extern \"C\" {\n #endif\n \n #include <stdint.h>\n+#ifdef RTE_MACHINE_CPUFLAG_SSE4_2\n #include <nmmintrin.h>\n+#endif\n+#include <rte_cpuflags.h>\n+#include <rte_branch_prediction.h>\n \n /* Lookup table for software implementation of CRC32C */\n static const uint32_t crc32c_table[256] = {\n@@ -152,8 +156,42 @@ crc32c_2words(uint64_t data, uint32_t init_val)\n \treturn init_val;\n }\n \n+enum crc32_alg_t {\n+\tCRC32_SW = 0,\n+\tCRC32_SSE42,\n+\tCRC32_AUTODETECT\n+};\n+\n+/* Default algorithm is left for autodetection,\n+ * it is detected on first run of hash function\n+ */\n+static enum crc32_alg_t crc32_alg = CRC32_AUTODETECT;\n+\n+/**\n+ * Allow or disallow use of SSE4.2 instrinsics for CRC32 hash\n+ * hash calculation.\n+ *\n+ * @param flag\n+ *   unsigned integer flag\n+ *   - (CRC32_SW) Don't use SSE4.2 intrinsics\n+ *   - (CRC32_SSE42) Use SSE4.2 intrinsics if available, set by default\n+ */\n+static inline void\n+rte_hash_crc_set_alg(enum crc32_alg_t alg)\n+{\n+\tint sse42_supp = rte_cpu_get_flag_enabled(RTE_CPUFLAG_SSE4_2);\n+\tenum crc32_alg_t alg_supp = sse42_supp ? CRC32_SSE42 : CRC32_SW;\n+\n+\tif (alg == CRC32_SSE42)\n+\t\tcrc32_alg = alg_supp;\n+\telse\n+\t\tcrc32_alg = CRC32_SW;\n+}\n+\n /**\n  * Use single crc32 instruction to perform a hash on a 4 byte value.\n+ * Fall back to software crc32 implementation in case SSE4.2 is\n+ * not supported\n  *\n  * @param data\n  *   Data to perform hash on.\n@@ -165,11 +203,21 @@ crc32c_2words(uint64_t data, uint32_t init_val)\n static inline uint32_t\n rte_hash_crc_4byte(uint32_t data, uint32_t init_val)\n {\n-\treturn _mm_crc32_u32(init_val, data);\n+\tif (unlikely(crc32_alg == CRC32_AUTODETECT))\n+\t\trte_hash_crc_set_alg(CRC32_SSE42);\n+\n+#ifdef RTE_MACHINE_CPUFLAG_SSE4_2\n+\tif (likely(crc32_alg == CRC32_SSE42))\n+\t\treturn _mm_crc32_u32(init_val, data);\n+#endif\n+\n+\treturn crc32c_1word(data, init_val);\n }\n \n /**\n  * Use single crc32 instruction to perform a hash on a 8 byte value.\n+ * Fall back to software crc32 implementation in case SSE4.2 is\n+ * not supported\n  *\n  * @param data\n  *   Data to perform hash on.\n@@ -181,7 +229,15 @@ rte_hash_crc_4byte(uint32_t data, uint32_t init_val)\n static inline uint32_t\n rte_hash_crc_8byte(uint64_t data, uint32_t init_val)\n {\n-\treturn _mm_crc32_u64(init_val, data);\n+\tif (unlikely(crc32_alg == CRC32_AUTODETECT))\n+\t\trte_hash_crc_set_alg(CRC32_SSE42);\n+\n+#ifdef RTE_MACHINE_CPUFLAG_SSE4_2\n+\tif (likely(crc32_alg == CRC32_SSE42))\n+\t\treturn _mm_crc32_u64(init_val, data);\n+#endif\n+\n+\treturn crc32c_2words(data, init_val);\n }\n \n /**\n",
    "prefixes": [
        "dpdk-dev",
        "v2",
        "3/4"
    ]
}