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GET /api/patches/967279/?format=api
HTTP 200 OK
Allow: GET, PUT, PATCH, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

{
    "id": 967279,
    "url": "http://patchwork.ozlabs.org/api/patches/967279/?format=api",
    "web_url": "http://patchwork.ozlabs.org/project/intel-wired-lan/patch/20180907081848.5438-3-bjorn.topel@gmail.com/",
    "project": {
        "id": 46,
        "url": "http://patchwork.ozlabs.org/api/projects/46/?format=api",
        "name": "Intel Wired Ethernet development",
        "link_name": "intel-wired-lan",
        "list_id": "intel-wired-lan.osuosl.org",
        "list_email": "intel-wired-lan@osuosl.org",
        "web_url": "",
        "scm_url": "",
        "webscm_url": "",
        "list_archive_url": "",
        "list_archive_url_format": "",
        "commit_url_format": ""
    },
    "msgid": "<20180907081848.5438-3-bjorn.topel@gmail.com>",
    "list_archive_url": null,
    "date": "2018-09-07T08:18:46",
    "name": "[v2,2/4] net: xsk: add a simple buffer reuse queue",
    "commit_ref": null,
    "pull_url": null,
    "state": "accepted",
    "archived": false,
    "hash": "0a9d164ceaed38a68f0a17e603b857e75cc6d2ba",
    "submitter": {
        "id": 70569,
        "url": "http://patchwork.ozlabs.org/api/people/70569/?format=api",
        "name": "Björn Töpel",
        "email": "bjorn.topel@gmail.com"
    },
    "delegate": {
        "id": 68,
        "url": "http://patchwork.ozlabs.org/api/users/68/?format=api",
        "username": "jtkirshe",
        "first_name": "Jeff",
        "last_name": "Kirsher",
        "email": "jeffrey.t.kirsher@intel.com"
    },
    "mbox": "http://patchwork.ozlabs.org/project/intel-wired-lan/patch/20180907081848.5438-3-bjorn.topel@gmail.com/mbox/",
    "series": [
        {
            "id": 64562,
            "url": "http://patchwork.ozlabs.org/api/series/64562/?format=api",
            "web_url": "http://patchwork.ozlabs.org/project/intel-wired-lan/list/?series=64562",
            "date": "2018-09-07T08:18:44",
            "name": "i40e AF_XDP zero-copy buffer leak fixes",
            "version": 2,
            "mbox": "http://patchwork.ozlabs.org/series/64562/mbox/"
        }
    ],
    "comments": "http://patchwork.ozlabs.org/api/patches/967279/comments/",
    "check": "pending",
    "checks": "http://patchwork.ozlabs.org/api/patches/967279/checks/",
    "tags": {},
    "related": [],
    "headers": {
        "Return-Path": "<intel-wired-lan-bounces@osuosl.org>",
        "X-Original-To": [
            "incoming@patchwork.ozlabs.org",
            "intel-wired-lan@lists.osuosl.org"
        ],
        "Delivered-To": [
            "patchwork-incoming@bilbo.ozlabs.org",
            "intel-wired-lan@lists.osuosl.org"
        ],
        "Authentication-Results": [
            "ozlabs.org;\n\tspf=pass (mailfrom) smtp.mailfrom=osuosl.org\n\t(client-ip=140.211.166.138; helo=whitealder.osuosl.org;\n\tenvelope-from=intel-wired-lan-bounces@osuosl.org;\n\treceiver=<UNKNOWN>)",
            "ozlabs.org;\n\tdmarc=fail (p=none dis=none) header.from=gmail.com"
        ],
        "Received": [
            "from whitealder.osuosl.org (smtp1.osuosl.org [140.211.166.138])\n\t(using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256\n\tbits)) (No client certificate requested)\n\tby ozlabs.org (Postfix) with ESMTPS id 4269Zz242yz9sBJ\n\tfor <incoming@patchwork.ozlabs.org>;\n\tFri,  7 Sep 2018 18:29:15 +1000 (AEST)",
            "from localhost (localhost [127.0.0.1])\n\tby whitealder.osuosl.org (Postfix) with ESMTP id AAFBD87F9B;\n\tFri,  7 Sep 2018 08:29:13 +0000 (UTC)",
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            "from ash.osuosl.org (ash.osuosl.org [140.211.166.34])\n\tby whitealder.osuosl.org (Postfix) with ESMTP id 8387287CB9;\n\tFri,  7 Sep 2018 08:29:11 +0000 (UTC)",
            "from whitealder.osuosl.org (smtp1.osuosl.org [140.211.166.138])\n\tby ash.osuosl.org (Postfix) with ESMTP id 51D341C0180\n\tfor <intel-wired-lan@lists.osuosl.org>;\n\tFri,  7 Sep 2018 08:29:10 +0000 (UTC)",
            "from localhost (localhost [127.0.0.1])\n\tby whitealder.osuosl.org (Postfix) with ESMTP id A8086877E7\n\tfor <intel-wired-lan@lists.osuosl.org>;\n\tFri,  7 Sep 2018 08:29:09 +0000 (UTC)",
            "from whitealder.osuosl.org ([127.0.0.1])\n\tby localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024)\n\twith ESMTP id piAdltDB6xWS for <intel-wired-lan@lists.osuosl.org>;\n\tFri,  7 Sep 2018 08:29:05 +0000 (UTC)",
            "from mga03.intel.com (mga03.intel.com [134.134.136.65])\n\tby whitealder.osuosl.org (Postfix) with ESMTPS id D5C99877FC\n\tfor <intel-wired-lan@lists.osuosl.org>;\n\tFri,  7 Sep 2018 08:29:04 +0000 (UTC)",
            "from orsmga001.jf.intel.com ([10.7.209.18])\n\tby orsmga103.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384;\n\t07 Sep 2018 01:19:34 -0700",
            "from btopel-mobl1.isw.intel.com ([10.103.211.147])\n\tby orsmga001.jf.intel.com with ESMTP; 07 Sep 2018 01:19:22 -0700"
        ],
        "X-Virus-Scanned": [
            "amavisd-new at osuosl.org",
            "amavisd-new at osuosl.org"
        ],
        "X-Greylist": "from auto-whitelisted by SQLgrey-1.7.6",
        "X-Amp-Result": "SKIPPED(no attachment in message)",
        "X-Amp-File-Uploaded": "False",
        "X-ExtLoop1": "1",
        "X-IronPort-AV": "E=Sophos;i=\"5.53,341,1531810800\"; d=\"scan'208\";a=\"88438112\"",
        "From": "=?utf-8?b?QmrDtnJuIFTDtnBlbA==?= <bjorn.topel@gmail.com>",
        "To": "ast@kernel.org, daniel@iogearbox.net, jeffrey.t.kirsher@intel.com,\n\tintel-wired-lan@lists.osuosl.org, jakub.kicinski@netronome.com",
        "Date": "Fri,  7 Sep 2018 10:18:46 +0200",
        "Message-Id": "<20180907081848.5438-3-bjorn.topel@gmail.com>",
        "X-Mailer": "git-send-email 2.17.1",
        "In-Reply-To": "<20180907081848.5438-1-bjorn.topel@gmail.com>",
        "References": "<20180907081848.5438-1-bjorn.topel@gmail.com>",
        "Subject": "[Intel-wired-lan] [PATCH v2 2/4] net: xsk: add a simple buffer\n\treuse queue",
        "X-BeenThere": "intel-wired-lan@osuosl.org",
        "X-Mailman-Version": "2.1.24",
        "Precedence": "list",
        "List-Id": "Intel Wired Ethernet Linux Kernel Driver Development\n\t<intel-wired-lan.osuosl.org>",
        "List-Unsubscribe": "<https://lists.osuosl.org/mailman/options/intel-wired-lan>, \n\t<mailto:intel-wired-lan-request@osuosl.org?subject=unsubscribe>",
        "List-Archive": "<http://lists.osuosl.org/pipermail/intel-wired-lan/>",
        "List-Post": "<mailto:intel-wired-lan@osuosl.org>",
        "List-Help": "<mailto:intel-wired-lan-request@osuosl.org?subject=help>",
        "List-Subscribe": "<https://lists.osuosl.org/mailman/listinfo/intel-wired-lan>, \n\t<mailto:intel-wired-lan-request@osuosl.org?subject=subscribe>",
        "Cc": "netdev@vger.kernel.org, magnus.karlsson@gmail.com,\n\tmagnus.karlsson@intel.com",
        "MIME-Version": "1.0",
        "Content-Type": "text/plain; charset=\"us-ascii\"",
        "Content-Transfer-Encoding": "7bit",
        "Errors-To": "intel-wired-lan-bounces@osuosl.org",
        "Sender": "\"Intel-wired-lan\" <intel-wired-lan-bounces@osuosl.org>"
    },
    "content": "From: Jakub Kicinski <jakub.kicinski@netronome.com>\n\nXSK UMEM is strongly single producer single consumer so reuse of\nframes is challenging.  Add a simple \"stash\" of FILL packets to\nreuse for drivers to optionally make use of.  This is useful\nwhen driver has to free (ndo_stop) or resize a ring with an active\nAF_XDP ZC socket.\n\nv2: Fixed build issues for !CONFIG_XDP_SOCKETS.\n\nSigned-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>\n---\n include/net/xdp_sock.h | 69 ++++++++++++++++++++++++++++++++++++++++++\n net/xdp/xdp_umem.c     |  2 ++\n net/xdp/xsk_queue.c    | 55 +++++++++++++++++++++++++++++++++\n net/xdp/xsk_queue.h    |  3 ++\n 4 files changed, 129 insertions(+)",
    "diff": "diff --git a/include/net/xdp_sock.h b/include/net/xdp_sock.h\nindex 932ca0dad6f3..70a115bea4f4 100644\n--- a/include/net/xdp_sock.h\n+++ b/include/net/xdp_sock.h\n@@ -21,6 +21,12 @@ struct xdp_umem_page {\n \tdma_addr_t dma;\n };\n \n+struct xdp_umem_fq_reuse {\n+\tu32 nentries;\n+\tu32 length;\n+\tu64 handles[];\n+};\n+\n struct xdp_umem {\n \tstruct xsk_queue *fq;\n \tstruct xsk_queue *cq;\n@@ -37,6 +43,7 @@ struct xdp_umem {\n \tstruct page **pgs;\n \tu32 npgs;\n \tstruct net_device *dev;\n+\tstruct xdp_umem_fq_reuse *fq_reuse;\n \tu16 queue_id;\n \tbool zc;\n \tspinlock_t xsk_list_lock;\n@@ -75,6 +82,10 @@ void xsk_umem_discard_addr(struct xdp_umem *umem);\n void xsk_umem_complete_tx(struct xdp_umem *umem, u32 nb_entries);\n bool xsk_umem_consume_tx(struct xdp_umem *umem, dma_addr_t *dma, u32 *len);\n void xsk_umem_consume_tx_done(struct xdp_umem *umem);\n+struct xdp_umem_fq_reuse *xsk_reuseq_prepare(u32 nentries);\n+struct xdp_umem_fq_reuse *xsk_reuseq_swap(struct xdp_umem *umem,\n+\t\t\t\t\t  struct xdp_umem_fq_reuse *newq);\n+void xsk_reuseq_free(struct xdp_umem_fq_reuse *rq);\n \n static inline char *xdp_umem_get_data(struct xdp_umem *umem, u64 addr)\n {\n@@ -85,6 +96,35 @@ static inline dma_addr_t xdp_umem_get_dma(struct xdp_umem *umem, u64 addr)\n {\n \treturn umem->pages[addr >> PAGE_SHIFT].dma + (addr & (PAGE_SIZE - 1));\n }\n+\n+/* Reuse-queue aware version of FILL queue helpers */\n+static inline u64 *xsk_umem_peek_addr_rq(struct xdp_umem *umem, u64 *addr)\n+{\n+\tstruct xdp_umem_fq_reuse *rq = umem->fq_reuse;\n+\n+\tif (!rq->length)\n+\t\treturn xsk_umem_peek_addr(umem, addr);\n+\n+\t*addr = rq->handles[rq->length - 1];\n+\treturn addr;\n+}\n+\n+static inline void xsk_umem_discard_addr_rq(struct xdp_umem *umem)\n+{\n+\tstruct xdp_umem_fq_reuse *rq = umem->fq_reuse;\n+\n+\tif (!rq->length)\n+\t\txsk_umem_discard_addr(umem);\n+\telse\n+\t\trq->length--;\n+}\n+\n+static inline void xsk_umem_fq_reuse(struct xdp_umem *umem, u64 addr)\n+{\n+\tstruct xdp_umem_fq_reuse *rq = umem->fq_reuse;\n+\n+\trq->handles[rq->length++] = addr;\n+}\n #else\n static inline int xsk_generic_rcv(struct xdp_sock *xs, struct xdp_buff *xdp)\n {\n@@ -128,6 +168,21 @@ static inline void xsk_umem_consume_tx_done(struct xdp_umem *umem)\n {\n }\n \n+static inline struct xdp_umem_fq_reuse *xsk_reuseq_prepare(u32 nentries)\n+{\n+\treturn NULL;\n+}\n+\n+static inline struct xdp_umem_fq_reuse *xsk_reuseq_swap(\n+\tstruct xdp_umem *umem,\n+\tstruct xdp_umem_fq_reuse *newq)\n+{\n+\treturn NULL;\n+}\n+static inline void xsk_reuseq_free(struct xdp_umem_fq_reuse *rq)\n+{\n+}\n+\n static inline char *xdp_umem_get_data(struct xdp_umem *umem, u64 addr)\n {\n \treturn NULL;\n@@ -137,6 +192,20 @@ static inline dma_addr_t xdp_umem_get_dma(struct xdp_umem *umem, u64 addr)\n {\n \treturn 0;\n }\n+\n+static inline u64 *xsk_umem_peek_addr_rq(struct xdp_umem *umem, u64 *addr)\n+{\n+\treturn NULL;\n+}\n+\n+static inline void xsk_umem_discard_addr_rq(struct xdp_umem *umem)\n+{\n+}\n+\n+static inline void xsk_umem_fq_reuse(struct xdp_umem *umem, u64 addr)\n+{\n+}\n+\n #endif /* CONFIG_XDP_SOCKETS */\n \n #endif /* _LINUX_XDP_SOCK_H */\ndiff --git a/net/xdp/xdp_umem.c b/net/xdp/xdp_umem.c\nindex b3b632c5aeae..555427b3e0fe 100644\n--- a/net/xdp/xdp_umem.c\n+++ b/net/xdp/xdp_umem.c\n@@ -165,6 +165,8 @@ static void xdp_umem_release(struct xdp_umem *umem)\n \t\tumem->cq = NULL;\n \t}\n \n+\txsk_reuseq_destroy(umem);\n+\n \txdp_umem_unpin_pages(umem);\n \n \ttask = get_pid_task(umem->pid, PIDTYPE_PID);\ndiff --git a/net/xdp/xsk_queue.c b/net/xdp/xsk_queue.c\nindex 2dc1384d9f27..b66504592d9b 100644\n--- a/net/xdp/xsk_queue.c\n+++ b/net/xdp/xsk_queue.c\n@@ -3,7 +3,9 @@\n  * Copyright(c) 2018 Intel Corporation.\n  */\n \n+#include <linux/log2.h>\n #include <linux/slab.h>\n+#include <linux/overflow.h>\n \n #include \"xsk_queue.h\"\n \n@@ -62,3 +64,56 @@ void xskq_destroy(struct xsk_queue *q)\n \tpage_frag_free(q->ring);\n \tkfree(q);\n }\n+\n+struct xdp_umem_fq_reuse *xsk_reuseq_prepare(u32 nentries)\n+{\n+\tstruct xdp_umem_fq_reuse *newq;\n+\n+\t/* Check for overflow */\n+\tif (nentries > (u32)roundup_pow_of_two(nentries))\n+\t\treturn NULL;\n+\tnentries = roundup_pow_of_two(nentries);\n+\n+\tnewq = kvmalloc(struct_size(newq, handles, nentries), GFP_KERNEL);\n+\tif (!newq)\n+\t\treturn NULL;\n+\tmemset(newq, 0, offsetof(typeof(*newq), handles));\n+\n+\tnewq->nentries = nentries;\n+\treturn newq;\n+}\n+EXPORT_SYMBOL_GPL(xsk_reuseq_prepare);\n+\n+struct xdp_umem_fq_reuse *xsk_reuseq_swap(struct xdp_umem *umem,\n+\t\t\t\t\t  struct xdp_umem_fq_reuse *newq)\n+{\n+\tstruct xdp_umem_fq_reuse *oldq = umem->fq_reuse;\n+\n+\tif (!oldq) {\n+\t\tumem->fq_reuse = newq;\n+\t\treturn NULL;\n+\t}\n+\n+\tif (newq->nentries < oldq->length)\n+\t\treturn newq;\n+\n+\tmemcpy(newq->handles, oldq->handles,\n+\t       array_size(oldq->length, sizeof(u64)));\n+\tnewq->length = oldq->length;\n+\n+\tumem->fq_reuse = newq;\n+\treturn oldq;\n+}\n+EXPORT_SYMBOL_GPL(xsk_reuseq_swap);\n+\n+void xsk_reuseq_free(struct xdp_umem_fq_reuse *rq)\n+{\n+\tkvfree(rq);\n+}\n+EXPORT_SYMBOL_GPL(xsk_reuseq_free);\n+\n+void xsk_reuseq_destroy(struct xdp_umem *umem)\n+{\n+\txsk_reuseq_free(umem->fq_reuse);\n+\tumem->fq_reuse = NULL;\n+}\ndiff --git a/net/xdp/xsk_queue.h b/net/xdp/xsk_queue.h\nindex 82252cccb4e0..bcb5cbb40419 100644\n--- a/net/xdp/xsk_queue.h\n+++ b/net/xdp/xsk_queue.h\n@@ -258,4 +258,7 @@ void xskq_set_umem(struct xsk_queue *q, u64 size, u64 chunk_mask);\n struct xsk_queue *xskq_create(u32 nentries, bool umem_queue);\n void xskq_destroy(struct xsk_queue *q_ops);\n \n+/* Executed by the core when the entire UMEM gets freed */\n+void xsk_reuseq_destroy(struct xdp_umem *umem);\n+\n #endif /* _LINUX_XSK_QUEUE_H */\n",
    "prefixes": [
        "v2",
        "2/4"
    ]
}