From patchwork Mon Nov 11 23:39:56 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: John Ousterhout X-Patchwork-Id: 13871459 X-Patchwork-Delegate: kuba@kernel.org Received: from smtp1.cs.Stanford.EDU (smtp1.cs.stanford.edu [171.64.64.25]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 57A5A198A38 for ; Mon, 11 Nov 2024 23:40:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=171.64.64.25 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731368453; cv=none; b=Wz6Qo/iKDu69ME9irwc99J/e6TS6Mc/zADOVRMjt/U8BiAZ/7q4Gk1t43FIrAGRoLXWeTTyoM32HEjr+W8JKIahVrwT2ggryXWPNN7qM10ffTwTTUpnMslpzmJJJgpr3hYbFrF/QJ3jNLeRj2uejyZk822rVSmrPv+H9ndZT1oE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731368453; c=relaxed/simple; bh=QiPq35SPKJ4eRlfOAwlcFZlfRkrdi6Xg4cjbk+8C/D4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=RZ/1xhkhZIIMUNFz9LBXeoZTdqfYVOALaoNM0GY0+hDu4VTFOEKXKBhdo/3JkADcXQrFYlG66WiRWymSOFoIBgSnax+xWecJsCbbgKRYOzUH/z1FqbP24uO7I1GdJ4P+DtBgJaljv4Vl7L3lNSd1+bQAJNwOfT7jTgwuilMZRMw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=cs.stanford.edu; spf=pass smtp.mailfrom=cs.stanford.edu; dkim=pass (2048-bit key) header.d=cs.stanford.edu header.i=@cs.stanford.edu header.b=nlScpjMl; arc=none smtp.client-ip=171.64.64.25 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=cs.stanford.edu Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=cs.stanford.edu Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=cs.stanford.edu header.i=@cs.stanford.edu header.b="nlScpjMl" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=cs.stanford.edu; s=cs2308; h=Content-Transfer-Encoding:MIME-Version: References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From:Sender:Reply-To: Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help: List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=fitKp9yhB53l7AHibiNU7N+zO5pIlssI0iDN4EdDqio=; t=1731368450; x=1732232450; b=nlScpjMlLYGnAPCR/O16fxAs1iwEXuFr28hulwk6ScU153uidmvQzEGz9WRCmmA/VG6c0u5ERdt o7SdvClTi8FFavLF4SmjIzu/FC60cG1epAKIIfuwH0/rrcf3WSBL+meSTOv6tiJV/JANgPc/RWjUL fM5t4ABDgL/qQRksd0LSTr9ZoYYbLyArP7VkSnCjthWumO3rc/1zK/4H6CehPE9VFqXF5ro0dgO+P YzMbLr/TFCtOCrhEX38bo8LYNaOQO84FQww9A7TPfP3HupljHQJDIOhSPjT/ClX39y5qmFcX4y28M bE38AB5qOozfRRz4wZaem3YdvZsRuxFfx/CQ==; Received: from ouster448.stanford.edu ([172.24.72.71]:54467 helo=localhost.localdomain) by smtp1.cs.Stanford.EDU with esmtpsa (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1tAe1S-0002NP-RI; Mon, 11 Nov 2024 15:40:44 -0800 From: John Ousterhout To: netdev@vger.kernel.org, linux-api@vger.kernel.org Cc: John Ousterhout Subject: [PATCH net-next v2 03/12] net: homa: create shared Homa header files Date: Mon, 11 Nov 2024 15:39:56 -0800 Message-ID: <20241111234006.5942-4-ouster@cs.stanford.edu> X-Mailer: git-send-email 2.45.1 In-Reply-To: <20241111234006.5942-1-ouster@cs.stanford.edu> References: <20241111234006.5942-1-ouster@cs.stanford.edu> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Spam-Score: -101.0 X-Scan-Signature: bcdc0f61a95607edd77a27aa99508360 X-Patchwork-Delegate: kuba@kernel.org homa_impl.h defines "struct homa", which contains overall information about the Homa transport, plus various odds and ends that are used throughout the Homa implementation. homa_stub.h is a temporary header file that provides stubs for facilities that have omitted for this first patch series. This file will go away once Home is fully upstreamed. Signed-off-by: John Ousterhout --- net/homa/homa_impl.h | 767 +++++++++++++++++++++++++++++++++++++++++++ net/homa/homa_stub.h | 80 +++++ 2 files changed, 847 insertions(+) create mode 100644 net/homa/homa_impl.h create mode 100644 net/homa/homa_stub.h diff --git a/net/homa/homa_impl.h b/net/homa/homa_impl.h new file mode 100644 index 000000000000..316a82b12ffa --- /dev/null +++ b/net/homa/homa_impl.h @@ -0,0 +1,767 @@ +/* SPDX-License-Identifier: BSD-2-Clause */ + +/* This file contains definitions that are shared across the files + * that implement Homa for Linux. + */ + +#ifndef _HOMA_IMPL_H +#define _HOMA_IMPL_H + +#include + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include "homa_wire.h" + +/* Forward declarations. */ +struct homa_peer; +struct homa_sock; +struct homa; + +/* Declarations used in this file, so they can't be made at the end. */ +void homa_throttle_lock_slow(struct homa *homa); + +#define sizeof32(type) ((int)(sizeof(type))) + +/** + * Holds either an IPv4 or IPv6 address (smaller and easier to use than + * sockaddr_storage). + */ +union sockaddr_in_union { + struct sockaddr sa; + struct sockaddr_in in4; + struct sockaddr_in6 in6; +}; + +/** + * struct homa_interest - Contains various information used while waiting + * for incoming messages (indicates what kinds of messages a particular + * thread is interested in receiving). + */ +struct homa_interest { + /** + * @thread: Thread that would like to receive a message. Will get + * woken up when a suitable message becomes available. + */ + struct task_struct *thread; + + /** + * @ready_rpc: This is actually a (struct homa_rpc *) identifying the + * RPC that was found; NULL if no RPC has been found yet. This + * variable is used for synchronization to handoff the RPC, and + * must be set only after @locked is set. + */ + atomic_long_t ready_rpc; + + /** + * @locked: Nonzero means that @ready_rpc is locked; only valid + * if @ready_rpc is non-NULL. + */ + int locked; + + /** + * @core: Core on which @thread was executing when it registered + * its interest. Used for load balancing (see balance.txt). + */ + int core; + + /** + * @reg_rpc: RPC whose @interest field points here, or + * NULL if none. + */ + struct homa_rpc *reg_rpc; + + /** + * @request_links: For linking this object into + * &homa_sock.request_interests. The interest must not be linked + * on either this list or @response_links if @id is nonzero. + */ + struct list_head request_links; + + /** + * @response_links: For linking this object into + * &homa_sock.request_interests. + */ + struct list_head response_links; +}; + +/** + * homa_interest_init() - Fill in default values for all of the fields + * of a struct homa_interest. + * @interest: Struct to initialize. + */ +static inline void homa_interest_init(struct homa_interest *interest) +{ + interest->thread = current; + atomic_long_set(&interest->ready_rpc, 0); + interest->locked = 0; + interest->core = raw_smp_processor_id(); + interest->reg_rpc = NULL; + interest->request_links.next = LIST_POISON1; + interest->response_links.next = LIST_POISON1; +} + +/** + * struct homa - Overall information about the Homa protocol implementation. + * + * There will typically only exist one of these at a time, except during + * unit tests. + */ +struct homa { + /** + * @next_outgoing_id: Id to use for next outgoing RPC request. + * This is always even: it's used only to generate client-side ids. + * Accessed without locks. + */ + atomic64_t next_outgoing_id; + + /** + * @link_idle_time: The time, measured by sched_clock at which we + * estimate that all of the packets we have passed to Linux for + * transmission will have been transmitted. May be in the past. + * This estimate assumes that only Homa is transmitting data, so + * it could be a severe underestimate if there is competing traffic + * from, say, TCP. Access only with atomic ops. + */ + atomic64_t link_idle_time __aligned(L1_CACHE_BYTES); + + /** + * @pacer_mutex: Ensures that only one instance of homa_pacer_xmit + * runs at a time. Only used in "try" mode: never block on this. + */ + spinlock_t pacer_mutex __aligned(L1_CACHE_BYTES); + + /** + * @pacer_fifo_fraction: The fraction of time (in thousandths) when + * the pacer should transmit next from the oldest message, rather + * than the highest-priority message. Set externally via sysctl. + */ + int pacer_fifo_fraction; + + /** + * @pacer_fifo_count: When this becomes <= zero, it's time for the + * pacer to allow the oldest RPC to transmit. + */ + int pacer_fifo_count; + + /** + * @pacer_wake_time: time (in sched_clock units) when the pacer last + * woke up (if the pacer is running) or 0 if the pacer is sleeping. + */ + __u64 pacer_wake_time; + + /** + * @throttle_lock: Used to synchronize access to @throttled_rpcs. To + * insert or remove an RPC from throttled_rpcs, must first acquire + * the RPC's socket lock, then this lock. + */ + spinlock_t throttle_lock; + + /** + * @throttled_rpcs: Contains all homa_rpcs that have bytes ready + * for transmission, but which couldn't be sent without exceeding + * the queue limits for transmission. Manipulate only with "_rcu" + * functions. + */ + struct list_head throttled_rpcs; + + /** + * @throttle_add: The time (in sched_clock() units) when the most + * recent RPC was added to @throttled_rpcs. + */ + __u64 throttle_add; + + /** + * @throttle_min_bytes: If a packet has fewer bytes than this, then it + * bypasses the throttle mechanism and is transmitted immediately. + * We have this limit because for very small packets we can't keep + * up with the NIC (we're limited by CPU overheads); there's no + * need for throttling and going through the throttle mechanism + * adds overhead, which slows things down. At least, that's the + * hypothesis (needs to be verified experimentally!). Set externally + * via sysctl. + */ + int throttle_min_bytes; + + /** + * @next_client_port: A client port number to consider for the + * next Homa socket; increments monotonically. Current value may + * be in the range allocated for servers; must check before using. + * This port may also be in use already; must check. + */ + __u16 next_client_port __aligned(L1_CACHE_BYTES); + + /** + * @port_map: Information about all open sockets. Dynamically + * allocated; must be kfreed. + */ + struct homa_socktab *port_map __aligned(L1_CACHE_BYTES); + + /** + * @peertab: Info about all the other hosts we have communicated with. + * Dynamically allocated; must be kfreed. + */ + struct homa_peertab *peers; + + /** @max_numa: Highest NUMA node id in use by any core. */ + int max_numa; + + /** + * @unsched_bytes: The number of bytes that may be sent in a + * new message without receiving any grants. There used to be a + * variable rtt_bytes that served this purpose, and was also used + * for window. Historically, rtt_bytes was intended to be the amount + * of data that can be transmitted over the wire in the time it + * takes to send a full-size data packet and receive back a grant. + * But, for fast networks that value could result in too much + * buffer utilization (and, we wanted to have separate values for + * @unsched_bytes and @window). Set externally via sysctl. + */ + int unsched_bytes; + + /** + * @window_param: Set externally via sysctl to select a policy for + * computing homa-grant_window. If 0 then homa->grant_window is + * computed dynamically based on the number of RPCs we're currently + * granting to. If nonzero then homa->grant_window will always be the + * same as @window_param. + */ + int window_param; + + /** + * @link_bandwidth: The raw bandwidth of the network uplink, in + * units of 1e06 bits per second. Set externally via sysctl. + */ + int link_mbps; + + /** + * @fifo_grant_increment: how many additional bytes to grant in + * a "pity" grant sent to the oldest outstanding message. Set + * externally via sysctl. + */ + int fifo_grant_increment; + + /** + * @grant_fifo_fraction: The fraction (in thousandths) of granted + * bytes that should go to the *oldest* incoming message, rather + * than the highest priority ones. Set externally via sysctl. + */ + int grant_fifo_fraction; + + /** + * @max_overcommit: The maximum number of messages to which Homa will + * send grants at any given point in time. Set externally via sysctl. + */ + int max_overcommit; + + /** + * @max_incoming: Homa will try to ensure that the total number of + * bytes senders have permission to send to this host (either + * unscheduled bytes or granted bytes) does not exceeds this value. + * Set externally via sysctl. + */ + int max_incoming; + + /** + * @max_rpcs_per_peer: If there are multiple incoming messages from + * the same peer, Homa will only issue grants to this many of them + * at a time. Set externally via sysctl. + */ + int max_rpcs_per_peer; + + /** + * @resend_ticks: When an RPC's @silent_ticks reaches this value, + * start sending RESEND requests. + */ + int resend_ticks; + + /** + * @resend_interval: minimum number of homa timer ticks between + * RESENDs for the same RPC. + */ + int resend_interval; + + /** + * @timeout_ticks: abort an RPC if its silent_ticks reaches this value. + */ + int timeout_ticks; + + /** + * @timeout_resends: Assume that a server is dead if it has not + * responded after this many RESENDs have been sent to it. + */ + int timeout_resends; + + /** + * @request_ack_ticks: How many timer ticks we'll wait for the + * client to ack an RPC before explicitly requesting an ack. + * Set externally via sysctl. + */ + int request_ack_ticks; + + /** + * @reap_limit: Maximum number of packet buffers to free in a + * single call to home_rpc_reap. + */ + int reap_limit; + + /** + * @dead_buffs_limit: If the number of packet buffers in dead but + * not yet reaped RPCs is less than this number, then Homa reaps + * RPCs in a way that minimizes impact on performance but may permit + * dead RPCs to accumulate. If the number of dead packet buffers + * exceeds this value, then Homa switches to a more aggressive approach + * to reaping RPCs. Set externally via sysctl. + */ + int dead_buffs_limit; + + /** + * @max_dead_buffs: The largest aggregate number of packet buffers + * in dead (but not yet reaped) RPCs that has existed so far in a + * single socket. Readable via sysctl, and may be reset via sysctl + * to begin recalculating. + */ + int max_dead_buffs; + + /** + * @pacer_kthread: Kernel thread that transmits packets from + * throttled_rpcs in a way that limits queue buildup in the + * NIC. + */ + struct task_struct *pacer_kthread; + + /** + * @pacer_exit: true means that the pacer thread should exit as + * soon as possible. + */ + bool pacer_exit; + + /** + * @max_nic_queue_ns: Limits the NIC queue length: we won't queue + * up a packet for transmission if link_idle_time is this many + * nanoseconds in the future (or more). Set externally via sysctl. + */ + int max_nic_queue_ns; + + /** + * @ns_per_mbyte: the number of ns that it takes to transmit + * 10**6 bytes on our uplink. This is actually a slight overestimate + * of the value, to ensure that we don't underestimate NIC queue + * length and queue too many packets. + */ + __u32 ns_per_mbyte; + + /** + * @max_gso_size: Maximum number of bytes that will be included + * in a single output packet that Homa passes to Linux. Can be set + * externally via sysctl to lower the limit already enforced by Linux. + */ + int max_gso_size; + + /** + * @gso_force_software: A non-zero value will cause Home to perform + * segmentation in software using GSO; zero means ask the NIC to + * perform TSO. Set externally via sysctl. + */ + int gso_force_software; + + /** + * @max_gro_skbs: Maximum number of socket buffers that can be + * aggregated by the GRO mechanism. Set externally via sysctl. + */ + int max_gro_skbs; + + /** + * @gro_policy: An OR'ed together collection of bits that determine + * how Homa packets should be steered for SoftIRQ handling. A value + * of zero will eliminate any Homa-specific behaviors, reverting + * to the Linux defaults. Set externally via sysctl (but modifying + * it is almost certainly a bad idea; see below). + */ + int gro_policy; + + /* Bits that can be specified for gro_policy. These were created for + * testing, in order to evaluate various possible policies; you almost + * certainly should not use any value other than HOMA_GRO_NORMAL. + * HOMA_GRO_SAME_CORE If isolated packets arrive (not part of + * a batch) use the GRO core for SoftIRQ also. + * HOMA_GRO_IDLE Use old mechanism for selecting an idle + * core for SoftIRQ (deprecated). + * HOMA_GRO_NEXT Always use the next core in circular + * order for SoftIRQ (deprecated). + * HOMA_GRO_GEN2 Use the new mechanism for selecting an + * idle core for SoftIRQ. + * HOMA_GRO_SHORT_BYPASS Pass all single-packet messages directly + * to homa_softirq during GRO (only if the + * core isn't overloaded). + * HOMA_GRO_GEN3 Use the "Gen3" mechanisms for load + * balancing. + */ + #define HOMA_GRO_SAME_CORE 2 + #define HOMA_GRO_IDLE 4 + #define HOMA_GRO_NEXT 8 + #define HOMA_GRO_GEN2 0x10 + #define HOMA_GRO_SHORT_BYPASS 0x40 + #define HOMA_GRO_GEN3 0x80 + #define HOMA_GRO_NORMAL (HOMA_GRO_SAME_CORE | HOMA_GRO_GEN2 | \ + HOMA_GRO_SHORT_BYPASS) + + /** + * @timer_ticks: number of times that homa_timer has been invoked + * (may wraparound, which is safe). + */ + __u32 timer_ticks; + + /** + * @flags: a collection of bits that can be set using sysctl + * to trigger various behaviors. + */ + int flags; + + /** + * @bpage_lease_usecs: how long a core can own a bpage (microseconds) + * before its ownership can be revoked to reclaim the page. + */ + int bpage_lease_usecs; + + /** + * @next_id: Set via sysctl; causes next_outgoing_id to be set to + * this value; always reads as zero. Typically used while debugging to + * ensure that different nodes use different ranges of ids. + */ + int next_id; + + /** + * @temp: the values in this array can be read and written with sysctl. + * They have no officially defined purpose, and are available for + * short-term use during testing. + */ + int temp[4]; +}; + +/** + * struct homa_skb_info - Additional information needed by Homa for each + * outbound DATA packet. Space is allocated for this at the very end of the + * linear part of the skb. + */ +struct homa_skb_info { + /** + * @next_skb: used to link together all of the skb's for a Homa + * message (in order of offset). + */ + struct sk_buff *next_skb; + + /** + * @wire_bytes: total number of bytes of network bandwidth that + * will be consumed by this packet. This includes everything, + * including additional headers added by GSO, IP header, Ethernet + * header, CRC, preamble, and inter-packet gap. + */ + int wire_bytes; + + /** + * @data_bytes: total bytes of message data across all of the + * segments in this packet. + */ + int data_bytes; + + /** @seg_length: maximum number of data bytes in each GSO segment. */ + int seg_length; + + /** + * @offset: offset within the message of the first byte of data in + * this packet. + */ + int offset; +}; + +/** + * homa_get_skb_info() - Return the address of Homa's private information + * for an sk_buff. + * @skb: Socket buffer whose info is needed. + */ +static inline struct homa_skb_info *homa_get_skb_info(struct sk_buff *skb) +{ + return (struct homa_skb_info *)(skb_end_pointer(skb) + - sizeof(struct homa_skb_info)); +} + +/** + * homa_next_skb() - Compute address of Homa's private link field in @skb. + * @skb: Socket buffer containing private link field. + * + * Homa needs to keep a list of buffers in a message, but it can't use the + * links built into sk_buffs because Homa wants to retain its list even + * after sending the packet, and the built-in links get used during sending. + * Thus we allocate extra space at the very end of the packet's data + * area to hold a forward pointer for a list. + */ +static inline struct sk_buff **homa_next_skb(struct sk_buff *skb) +{ + return (struct sk_buff **)(skb_end_pointer(skb) - sizeof(char *)); +} + +/** + * homa_set_doff() - Fills in the doff TCP header field for a Homa packet. + * @h: Packet header whose doff field is to be set. + * @size: Size of the "header", bytes (must be a multiple of 4). This + * information is used only for TSO; it's the number of bytes + * that should be replicated in each segment. The bytes after + * this will be distributed among segments. + */ +static inline void homa_set_doff(struct data_header *h, int size) +{ + h->common.doff = size << 2; +} + +/** + * homa_throttle_lock() - Acquire the throttle lock. If the lock + * isn't immediately available, record stats on the waiting time. + * @homa: Overall data about the Homa protocol implementation. + */ +// static inline void homa_throttle_lock(struct homa *homa) +// __acquires(THROTTLE_LOCK) +// { +// if (!spin_trylock_bh(&homa->throttle_lock)) +// homa_throttle_lock_slow(homa); +// } + +#define homa_throttle_lock(_homa) do { \ + struct homa *h = _homa; \ + if (!spin_trylock_bh(&h->throttle_lock)) \ + homa_throttle_lock_slow(h); \ +} while (0) + +/** + * homa_throttle_unlock() - Release the throttle lock. + * @homa: Overall data about the Homa protocol implementation. + */ +static inline void homa_throttle_unlock(struct homa *homa) + __releases(&homa->throttle_lock) +{ + spin_unlock_bh(&homa->throttle_lock); +} + +/** skb_is_ipv6() - Return true if the packet is encapsulated with IPv6, + * false otherwise (presumably it's IPv4). + */ +static inline bool skb_is_ipv6(const struct sk_buff *skb) +{ + return ipv6_hdr(skb)->version == 6; +} + +/** + * Given an IPv4 address, return an equivalent IPv6 address (an IPv4-mapped + * one) + * @ip4: IPv4 address, in network byte order. + */ +static inline struct in6_addr ipv4_to_ipv6(__be32 ip4) +{ + struct in6_addr ret = {}; + + if (ip4 == htonl(INADDR_ANY)) + return in6addr_any; + ret.in6_u.u6_addr32[2] = htonl(0xffff); + ret.in6_u.u6_addr32[3] = ip4; + return ret; +} + +/** + * ipv6_to_ipv4() - Given an IPv6 address produced by ipv4_to_ipv6, return + * the original IPv4 address (in network byte order). + * @ip6: IPv6 address; assumed to be a mapped IPv4 address. + */ +static inline __be32 ipv6_to_ipv4(const struct in6_addr ip6) +{ + return ip6.in6_u.u6_addr32[3]; +} + +/** + * skb_canonical_ipv6_addr() - Convert a socket address to the "standard" + * form used in Homa, which is always an IPv6 address; if the original address + * was IPv4, convert it to an IPv4-mapped IPv6 address. + * @addr: Address to canonicalize (if NULL, "any" is returned). + */ +static inline struct in6_addr canonical_ipv6_addr(const union sockaddr_in_union *addr) +{ + if (addr) { + return (addr->sa.sa_family == AF_INET6) + ? addr->in6.sin6_addr + : ipv4_to_ipv6(addr->in4.sin_addr.s_addr); + } else { + return in6addr_any; + } +} + +/** + * skb_canonical_ipv6_saddr() - Given a packet buffer, return its source + * address in the "standard" form used in Homa, which is always an IPv6 + * address; if the original address was IPv4, convert it to an IPv4-mapped + * IPv6 address. + * @skb: The source address will be extracted from this packet buffer. + */ +static inline struct in6_addr skb_canonical_ipv6_saddr(struct sk_buff *skb) +{ + return skb_is_ipv6(skb) ? ipv6_hdr(skb)->saddr + : ipv4_to_ipv6(ip_hdr(skb)->saddr); +} + +/** + * is_mapped_ipv4() - Return true if an IPv6 address is actually an + * IPv4-mapped address, false otherwise. + * @x: The address to check. + */ +static inline bool is_mapped_ipv4(const struct in6_addr x) +{ + return ((x.in6_u.u6_addr32[0] == 0) && + (x.in6_u.u6_addr32[1] == 0) && + (x.in6_u.u6_addr32[2] == htonl(0xffff))); +} + +/** + * tt_addr() - Given an address, return a 4-byte id that will (hopefully) + * provide a unique identifier for the address in a timetrace record. + * @x: Address (either IPv6 or IPv4-mapped IPv6) + */ +static inline __u32 tt_addr(const struct in6_addr x) +{ + return is_mapped_ipv4(x) ? ntohl(x.in6_u.u6_addr32[3]) + : (x.in6_u.u6_addr32[3] ? ntohl(x.in6_u.u6_addr32[3]) + : ntohl(x.in6_u.u6_addr32[1])); +} + +void homa_abort_rpcs(struct homa *homa, const struct in6_addr *addr, + int port, int error); +void homa_abort_sock_rpcs(struct homa_sock *hsk, int error); +void homa_ack_pkt(struct sk_buff *skb, struct homa_sock *hsk, + struct homa_rpc *rpc); +void homa_add_packet(struct homa_rpc *rpc, struct sk_buff *skb); +void homa_add_to_throttled(struct homa_rpc *rpc); +int homa_backlog_rcv(struct sock *sk, struct sk_buff *skb); +int homa_bind(struct socket *sk, struct sockaddr *addr, + int addr_len); +int homa_check_nic_queue(struct homa *homa, struct sk_buff *skb, + bool force); +struct homa_interest *homa_choose_interest(struct homa *homa, + struct list_head *head, + int offset); +void homa_close(struct sock *sock, long timeout); +int homa_copy_to_user(struct homa_rpc *rpc); +void homa_data_from_server(struct sk_buff *skb, + struct homa_rpc *crpc); +void homa_data_pkt(struct sk_buff *skb, struct homa_rpc *rpc); +void homa_destroy(struct homa *homa); +int homa_disconnect(struct sock *sk, int flags); +void homa_dispatch_pkts(struct sk_buff *skb, struct homa *homa); +int homa_err_handler_v4(struct sk_buff *skb, u32 info); +int homa_err_handler_v6(struct sk_buff *skb, + struct inet6_skb_parm *opt, u8 type, u8 code, + int offset, __be32 info); +int homa_fill_data_interleaved(struct homa_rpc *rpc, + struct sk_buff *skb, struct iov_iter *iter); +struct homa_gap *homa_gap_new(struct list_head *next, int start, int end); +void homa_gap_retry(struct homa_rpc *rpc); +int homa_get_port(struct sock *sk, unsigned short snum); +int homa_getsockopt(struct sock *sk, int level, int optname, + char __user *optval, int __user *option); +int homa_hash(struct sock *sk); +enum hrtimer_restart homa_hrtimer(struct hrtimer *timer); +int homa_init(struct homa *homa); +void homa_incoming_sysctl_changed(struct homa *homa); +int homa_ioctl(struct sock *sk, int cmd, int *karg); +int homa_message_in_init(struct homa_rpc *rpc, int length); +int homa_message_out_fill(struct homa_rpc *rpc, + struct iov_iter *iter, int xmit); +void homa_message_out_init(struct homa_rpc *rpc, int length); +void homa_need_ack_pkt(struct sk_buff *skb, struct homa_sock *hsk, + struct homa_rpc *rpc); +struct sk_buff *homa_new_data_packet(struct homa_rpc *rpc, + struct iov_iter *iter, int offset, + int length, int max_seg_data); +void homa_outgoing_sysctl_changed(struct homa *homa); +int homa_pacer_main(void *transport); +void homa_pacer_stop(struct homa *homa); +void homa_pacer_xmit(struct homa *homa); +__poll_t homa_poll(struct file *file, struct socket *sock, + struct poll_table_struct *wait); +int homa_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, + int flags, int *addr_len); +int homa_register_interests(struct homa_interest *interest, + struct homa_sock *hsk, int flags, __u64 id); +void homa_remove_from_throttled(struct homa_rpc *rpc); +void homa_resend_data(struct homa_rpc *rpc, int start, int end); +void homa_resend_pkt(struct sk_buff *skb, struct homa_rpc *rpc, + struct homa_sock *hsk); +void homa_rpc_abort(struct homa_rpc *crpc, int error); +void homa_rpc_acked(struct homa_sock *hsk, + const struct in6_addr *saddr, struct homa_ack *ack); +void homa_rpc_free(struct homa_rpc *rpc); +void homa_rpc_handoff(struct homa_rpc *rpc); +int homa_sendmsg(struct sock *sk, struct msghdr *msg, size_t len); +int homa_setsockopt(struct sock *sk, int level, int optname, + sockptr_t optval, unsigned int optlen); +int homa_shutdown(struct socket *sock, int how); +int homa_softirq(struct sk_buff *skb); +void homa_spin(int ns); +char *homa_symbol_for_type(uint8_t type); +void homa_timer(struct homa *homa); +int homa_timer_main(void *transport); +void homa_unhash(struct sock *sk); +void homa_unknown_pkt(struct sk_buff *skb, struct homa_rpc *rpc); +struct homa_rpc *homa_wait_for_message(struct homa_sock *hsk, int flags, + __u64 id); +int homa_xmit_control(enum homa_packet_type type, void *contents, + size_t length, struct homa_rpc *rpc); +int __homa_xmit_control(void *contents, size_t length, + struct homa_peer *peer, struct homa_sock *hsk); +void homa_xmit_data(struct homa_rpc *rpc, bool force); +void __homa_xmit_data(struct sk_buff *skb, struct homa_rpc *rpc); +void homa_xmit_unknown(struct sk_buff *skb, struct homa_sock *hsk); + +/** + * homa_check_pacer() - This method is invoked at various places in Homa to + * see if the pacer needs to transmit more packets and, if so, transmit + * them. It's needed because the pacer thread may get descheduled by + * Linux, result in output stalls. + * @homa: Overall data about the Homa protocol implementation. No locks + * should be held when this function is invoked. + * @softirq: Nonzero means this code is running at softirq (bh) level; + * zero means it's running in process context. + */ +static inline void homa_check_pacer(struct homa *homa, int softirq) +{ + if (list_empty(&homa->throttled_rpcs)) + return; + + /* The ">> 1" in the line below gives homa_pacer_main the first chance + * to queue new packets; if the NIC queue becomes more than half + * empty, then we will help out here. + */ + if ((sched_clock() + (homa->max_nic_queue_ns >> 1)) < + atomic64_read(&homa->link_idle_time)) + return; + homa_pacer_xmit(homa); +} + +extern struct completion homa_pacer_kthread_done; +#endif /* _HOMA_IMPL_H */ diff --git a/net/homa/homa_stub.h b/net/homa/homa_stub.h new file mode 100644 index 000000000000..fb2ba4195dd2 --- /dev/null +++ b/net/homa/homa_stub.h @@ -0,0 +1,80 @@ +/* SPDX-License-Identifier: BSD-2-Clause */ + +/* This file contains stripped-down replacements that have been + * temporarily removed from Homa during the Linux upstreaming + * process. By the time upstreaming is complete this file will + * have gone away. + */ + +#ifndef _HOMA_STUB_H +#define _HOMA_STUB_H + +#include "homa_impl.h" + +static inline int homa_skb_append_from_iter(struct homa *homa, + struct sk_buff *skb, + struct iov_iter *iter, int length) +{ + char *dst = skb_put(skb, length); + + if (copy_from_iter(dst, length, iter) != length) + return -EFAULT; + return 0; +} + +static inline int homa_skb_append_to_frag(struct homa *homa, struct sk_buff *skb, + void *buf, int length) +{ + char *dst = skb_put(skb, length); + + memcpy(dst, buf, length); + return 0; +} + +static inline int homa_skb_append_from_skb(struct homa *homa, + struct sk_buff *dst_skb, + struct sk_buff *src_skb, + int offset, int length) +{ + return homa_skb_append_to_frag(homa, dst_skb, + skb_transport_header(src_skb) + offset, length); +} + +static inline void homa_skb_free_tx(struct homa *homa, struct sk_buff *skb) +{ + kfree_skb(skb); +} + +static inline void homa_skb_free_many_tx(struct homa *homa, + struct sk_buff **skbs, int count) +{ + int i; + + for (i = 0; i < count; i++) + kfree_skb(skbs[i]); +} + +static inline void homa_skb_get(struct sk_buff *skb, void *dest, int offset, + int length) +{ + memcpy(dest, skb_transport_header(skb) + offset, length); +} + +static inline struct sk_buff *homa_skb_new_tx(int length) +{ + struct sk_buff *skb; + + skb = alloc_skb(HOMA_SKB_EXTRA + HOMA_IPV6_HEADER_LENGTH + + sizeof(struct homa_skb_info) + length, + GFP_KERNEL); + if (likely(skb)) { + skb_reserve(skb, HOMA_SKB_EXTRA + HOMA_IPV6_HEADER_LENGTH); + skb_reset_transport_header(skb); + } + return skb; +} + +static inline void homa_skb_stash_pages(struct homa *homa, int length) +{} + +#endif /* _HOMA_STUB_H */