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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /arch/ia64/lib/do_csum.S
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Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
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+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ *
+ * Optmized version of the standard do_csum() function
+ *
+ * Return: a 64bit quantity containing the 16bit Internet checksum
+ *
+ * Inputs:
+ * in0: address of buffer to checksum (char *)
+ * in1: length of the buffer (int)
+ *
+ * Copyright (C) 1999, 2001-2002 Hewlett-Packard Co
+ * Stephane Eranian <eranian@hpl.hp.com>
+ *
+ * 02/04/22 Ken Chen <kenneth.w.chen@intel.com>
+ * Data locality study on the checksum buffer.
+ * More optimization cleanup - remove excessive stop bits.
+ * 02/04/08 David Mosberger <davidm@hpl.hp.com>
+ * More cleanup and tuning.
+ * 01/04/18 Jun Nakajima <jun.nakajima@intel.com>
+ * Clean up and optimize and the software pipeline, loading two
+ * back-to-back 8-byte words per loop. Clean up the initialization
+ * for the loop. Support the cases where load latency = 1 or 2.
+ * Set CONFIG_IA64_LOAD_LATENCY to 1 or 2 (default).
+ */
+
+#include <asm/asmmacro.h>
+
+//
+// Theory of operations:
+// The goal is to go as quickly as possible to the point where
+// we can checksum 16 bytes/loop. Before reaching that point we must
+// take care of incorrect alignment of first byte.
+//
+// The code hereafter also takes care of the "tail" part of the buffer
+// before entering the core loop, if any. The checksum is a sum so it
+// allows us to commute operations. So we do the "head" and "tail"
+// first to finish at full speed in the body. Once we get the head and
+// tail values, we feed them into the pipeline, very handy initialization.
+//
+// Of course we deal with the special case where the whole buffer fits
+// into one 8 byte word. In this case we have only one entry in the pipeline.
+//
+// We use a (LOAD_LATENCY+2)-stage pipeline in the loop to account for
+// possible load latency and also to accommodate for head and tail.
+//
+// The end of the function deals with folding the checksum from 64bits
+// down to 16bits taking care of the carry.
+//
+// This version avoids synchronization in the core loop by also using a
+// pipeline for the accumulation of the checksum in resultx[] (x=1,2).
+//
+// wordx[] (x=1,2)
+// |---|
+// | | 0 : new value loaded in pipeline
+// |---|
+// | | - : in transit data
+// |---|
+// | | LOAD_LATENCY : current value to add to checksum
+// |---|
+// | | LOAD_LATENCY+1 : previous value added to checksum
+// |---| (previous iteration)
+//
+// resultx[] (x=1,2)
+// |---|
+// | | 0 : initial value
+// |---|
+// | | LOAD_LATENCY-1 : new checksum
+// |---|
+// | | LOAD_LATENCY : previous value of checksum
+// |---|
+// | | LOAD_LATENCY+1 : final checksum when out of the loop
+// |---|
+//
+//
+// See RFC1071 "Computing the Internet Checksum" for various techniques for
+// calculating the Internet checksum.
+//
+// NOT YET DONE:
+// - Maybe another algorithm which would take care of the folding at the
+// end in a different manner
+// - Work with people more knowledgeable than me on the network stack
+// to figure out if we could not split the function depending on the
+// type of packet or alignment we get. Like the ip_fast_csum() routine
+// where we know we have at least 20bytes worth of data to checksum.
+// - Do a better job of handling small packets.
+// - Note on prefetching: it was found that under various load, i.e. ftp read/write,
+// nfs read/write, the L1 cache hit rate is at 60% and L2 cache hit rate is at 99.8%
+// on the data that buffer points to (partly because the checksum is often preceded by
+// a copy_from_user()). This finding indiate that lfetch will not be beneficial since
+// the data is already in the cache.
+//
+
+#define saved_pfs r11
+#define hmask r16
+#define tmask r17
+#define first1 r18
+#define firstval r19
+#define firstoff r20
+#define last r21
+#define lastval r22
+#define lastoff r23
+#define saved_lc r24
+#define saved_pr r25
+#define tmp1 r26
+#define tmp2 r27
+#define tmp3 r28
+#define carry1 r29
+#define carry2 r30
+#define first2 r31
+
+#define buf in0
+#define len in1
+
+#define LOAD_LATENCY 2 // XXX fix me
+
+#if (LOAD_LATENCY != 1) && (LOAD_LATENCY != 2)
+# error "Only 1 or 2 is supported/tested for LOAD_LATENCY."
+#endif
+
+#define PIPE_DEPTH (LOAD_LATENCY+2)
+#define ELD p[LOAD_LATENCY] // end of load
+#define ELD_1 p[LOAD_LATENCY+1] // and next stage
+
+// unsigned long do_csum(unsigned char *buf,long len)
+
+GLOBAL_ENTRY(do_csum)
+ .prologue
+ .save ar.pfs, saved_pfs
+ alloc saved_pfs=ar.pfs,2,16,0,16
+ .rotr word1[4], word2[4],result1[LOAD_LATENCY+2],result2[LOAD_LATENCY+2]
+ .rotp p[PIPE_DEPTH], pC1[2], pC2[2]
+ mov ret0=r0 // in case we have zero length
+ cmp.lt p0,p6=r0,len // check for zero length or negative (32bit len)
+ ;;
+ add tmp1=buf,len // last byte's address
+ .save pr, saved_pr
+ mov saved_pr=pr // preserve predicates (rotation)
+(p6) br.ret.spnt.many rp // return if zero or negative length
+
+ mov hmask=-1 // initialize head mask
+ tbit.nz p15,p0=buf,0 // is buf an odd address?
+ and first1=-8,buf // 8-byte align down address of first1 element
+
+ and firstoff=7,buf // how many bytes off for first1 element
+ mov tmask=-1 // initialize tail mask
+
+ ;;
+ adds tmp2=-1,tmp1 // last-1
+ and lastoff=7,tmp1 // how many bytes off for last element
+ ;;
+ sub tmp1=8,lastoff // complement to lastoff
+ and last=-8,tmp2 // address of word containing last byte
+ ;;
+ sub tmp3=last,first1 // tmp3=distance from first1 to last
+ .save ar.lc, saved_lc
+ mov saved_lc=ar.lc // save lc
+ cmp.eq p8,p9=last,first1 // everything fits in one word ?
+
+ ld8 firstval=[first1],8 // load, ahead of time, "first1" word
+ and tmp1=7, tmp1 // make sure that if tmp1==8 -> tmp1=0
+ shl tmp2=firstoff,3 // number of bits
+ ;;
+(p9) ld8 lastval=[last] // load, ahead of time, "last" word, if needed
+ shl tmp1=tmp1,3 // number of bits
+(p9) adds tmp3=-8,tmp3 // effectively loaded
+ ;;
+(p8) mov lastval=r0 // we don't need lastval if first1==last
+ shl hmask=hmask,tmp2 // build head mask, mask off [0,first1off[
+ shr.u tmask=tmask,tmp1 // build tail mask, mask off ]8,lastoff]
+ ;;
+ .body
+#define count tmp3
+
+(p8) and hmask=hmask,tmask // apply tail mask to head mask if 1 word only
+(p9) and word2[0]=lastval,tmask // mask last it as appropriate
+ shr.u count=count,3 // how many 8-byte?
+ ;;
+ // If count is odd, finish this 8-byte word so that we can
+ // load two back-to-back 8-byte words per loop thereafter.
+ and word1[0]=firstval,hmask // and mask it as appropriate
+ tbit.nz p10,p11=count,0 // if (count is odd)
+ ;;
+(p8) mov result1[0]=word1[0]
+(p9) add result1[0]=word1[0],word2[0]
+ ;;
+ cmp.ltu p6,p0=result1[0],word1[0] // check the carry
+ cmp.eq.or.andcm p8,p0=0,count // exit if zero 8-byte
+ ;;
+(p6) adds result1[0]=1,result1[0]
+(p8) br.cond.dptk .do_csum_exit // if (within an 8-byte word)
+(p11) br.cond.dptk .do_csum16 // if (count is even)
+
+ // Here count is odd.
+ ld8 word1[1]=[first1],8 // load an 8-byte word
+ cmp.eq p9,p10=1,count // if (count == 1)
+ adds count=-1,count // loaded an 8-byte word
+ ;;
+ add result1[0]=result1[0],word1[1]
+ ;;
+ cmp.ltu p6,p0=result1[0],word1[1]
+ ;;
+(p6) adds result1[0]=1,result1[0]
+(p9) br.cond.sptk .do_csum_exit // if (count == 1) exit
+ // Fall through to calculate the checksum, feeding result1[0] as
+ // the initial value in result1[0].
+ //
+ // Calculate the checksum loading two 8-byte words per loop.
+ //
+.do_csum16:
+ add first2=8,first1
+ shr.u count=count,1 // we do 16 bytes per loop
+ ;;
+ adds count=-1,count
+ mov carry1=r0
+ mov carry2=r0
+ brp.loop.imp 1f,2f
+ ;;
+ mov ar.ec=PIPE_DEPTH
+ mov ar.lc=count // set lc
+ mov pr.rot=1<<16
+ // result1[0] must be initialized in advance.
+ mov result2[0]=r0
+ ;;
+ .align 32
+1:
+(ELD_1) cmp.ltu pC1[0],p0=result1[LOAD_LATENCY],word1[LOAD_LATENCY+1]
+(pC1[1])adds carry1=1,carry1
+(ELD_1) cmp.ltu pC2[0],p0=result2[LOAD_LATENCY],word2[LOAD_LATENCY+1]
+(pC2[1])adds carry2=1,carry2
+(ELD) add result1[LOAD_LATENCY-1]=result1[LOAD_LATENCY],word1[LOAD_LATENCY]
+(ELD) add result2[LOAD_LATENCY-1]=result2[LOAD_LATENCY],word2[LOAD_LATENCY]
+2:
+(p[0]) ld8 word1[0]=[first1],16
+(p[0]) ld8 word2[0]=[first2],16
+ br.ctop.sptk 1b
+ ;;
+ // Since len is a 32-bit value, carry cannot be larger than a 64-bit value.
+(pC1[1])adds carry1=1,carry1 // since we miss the last one
+(pC2[1])adds carry2=1,carry2
+ ;;
+ add result1[LOAD_LATENCY+1]=result1[LOAD_LATENCY+1],carry1
+ add result2[LOAD_LATENCY+1]=result2[LOAD_LATENCY+1],carry2
+ ;;
+ cmp.ltu p6,p0=result1[LOAD_LATENCY+1],carry1
+ cmp.ltu p7,p0=result2[LOAD_LATENCY+1],carry2
+ ;;
+(p6) adds result1[LOAD_LATENCY+1]=1,result1[LOAD_LATENCY+1]
+(p7) adds result2[LOAD_LATENCY+1]=1,result2[LOAD_LATENCY+1]
+ ;;
+ add result1[0]=result1[LOAD_LATENCY+1],result2[LOAD_LATENCY+1]
+ ;;
+ cmp.ltu p6,p0=result1[0],result2[LOAD_LATENCY+1]
+ ;;
+(p6) adds result1[0]=1,result1[0]
+ ;;
+.do_csum_exit:
+ //
+ // now fold 64 into 16 bits taking care of carry
+ // that's not very good because it has lots of sequentiality
+ //
+ mov tmp3=0xffff
+ zxt4 tmp1=result1[0]
+ shr.u tmp2=result1[0],32
+ ;;
+ add result1[0]=tmp1,tmp2
+ ;;
+ and tmp1=result1[0],tmp3
+ shr.u tmp2=result1[0],16
+ ;;
+ add result1[0]=tmp1,tmp2
+ ;;
+ and tmp1=result1[0],tmp3
+ shr.u tmp2=result1[0],16
+ ;;
+ add result1[0]=tmp1,tmp2
+ ;;
+ and tmp1=result1[0],tmp3
+ shr.u tmp2=result1[0],16
+ ;;
+ add ret0=tmp1,tmp2
+ mov pr=saved_pr,0xffffffffffff0000
+ ;;
+ // if buf was odd then swap bytes
+ mov ar.pfs=saved_pfs // restore ar.ec
+(p15) mux1 ret0=ret0,@rev // reverse word
+ ;;
+ mov ar.lc=saved_lc
+(p15) shr.u ret0=ret0,64-16 // + shift back to position = swap bytes
+ br.ret.sptk.many rp
+
+// I (Jun Nakajima) wrote an equivalent code (see below), but it was
+// not much better than the original. So keep the original there so that
+// someone else can challenge.
+//
+// shr.u word1[0]=result1[0],32
+// zxt4 result1[0]=result1[0]
+// ;;
+// add result1[0]=result1[0],word1[0]
+// ;;
+// zxt2 result2[0]=result1[0]
+// extr.u word1[0]=result1[0],16,16
+// shr.u carry1=result1[0],32
+// ;;
+// add result2[0]=result2[0],word1[0]
+// ;;
+// add result2[0]=result2[0],carry1
+// ;;
+// extr.u ret0=result2[0],16,16
+// ;;
+// add ret0=ret0,result2[0]
+// ;;
+// zxt2 ret0=ret0
+// mov ar.pfs=saved_pfs // restore ar.ec
+// mov pr=saved_pr,0xffffffffffff0000
+// ;;
+// // if buf was odd then swap bytes
+// mov ar.lc=saved_lc
+//(p15) mux1 ret0=ret0,@rev // reverse word
+// ;;
+//(p15) shr.u ret0=ret0,64-16 // + shift back to position = swap bytes
+// br.ret.sptk.many rp
+
+END(do_csum)