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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/s390/lib/spinlock.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
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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(). ...
Diffstat (limited to '')
-rw-r--r--arch/s390/lib/spinlock.c324
1 files changed, 324 insertions, 0 deletions
diff --git a/arch/s390/lib/spinlock.c b/arch/s390/lib/spinlock.c
new file mode 100644
index 000000000..04d4c6cf8
--- /dev/null
+++ b/arch/s390/lib/spinlock.c
@@ -0,0 +1,324 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Out of line spinlock code.
+ *
+ * Copyright IBM Corp. 2004, 2006
+ * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
+ */
+
+#include <linux/types.h>
+#include <linux/export.h>
+#include <linux/spinlock.h>
+#include <linux/jiffies.h>
+#include <linux/init.h>
+#include <linux/smp.h>
+#include <linux/percpu.h>
+#include <asm/alternative.h>
+#include <asm/io.h>
+
+int spin_retry = -1;
+
+static int __init spin_retry_init(void)
+{
+ if (spin_retry < 0)
+ spin_retry = 1000;
+ return 0;
+}
+early_initcall(spin_retry_init);
+
+/*
+ * spin_retry= parameter
+ */
+static int __init spin_retry_setup(char *str)
+{
+ spin_retry = simple_strtoul(str, &str, 0);
+ return 1;
+}
+__setup("spin_retry=", spin_retry_setup);
+
+struct spin_wait {
+ struct spin_wait *next, *prev;
+ int node_id;
+} __aligned(32);
+
+static DEFINE_PER_CPU_ALIGNED(struct spin_wait, spin_wait[4]);
+
+#define _Q_LOCK_CPU_OFFSET 0
+#define _Q_LOCK_STEAL_OFFSET 16
+#define _Q_TAIL_IDX_OFFSET 18
+#define _Q_TAIL_CPU_OFFSET 20
+
+#define _Q_LOCK_CPU_MASK 0x0000ffff
+#define _Q_LOCK_STEAL_ADD 0x00010000
+#define _Q_LOCK_STEAL_MASK 0x00030000
+#define _Q_TAIL_IDX_MASK 0x000c0000
+#define _Q_TAIL_CPU_MASK 0xfff00000
+
+#define _Q_LOCK_MASK (_Q_LOCK_CPU_MASK | _Q_LOCK_STEAL_MASK)
+#define _Q_TAIL_MASK (_Q_TAIL_IDX_MASK | _Q_TAIL_CPU_MASK)
+
+void arch_spin_lock_setup(int cpu)
+{
+ struct spin_wait *node;
+ int ix;
+
+ node = per_cpu_ptr(&spin_wait[0], cpu);
+ for (ix = 0; ix < 4; ix++, node++) {
+ memset(node, 0, sizeof(*node));
+ node->node_id = ((cpu + 1) << _Q_TAIL_CPU_OFFSET) +
+ (ix << _Q_TAIL_IDX_OFFSET);
+ }
+}
+
+static inline int arch_load_niai4(int *lock)
+{
+ int owner;
+
+ asm_inline volatile(
+ ALTERNATIVE("nop", ".insn rre,0xb2fa0000,4,0", 49) /* NIAI 4 */
+ " l %0,%1\n"
+ : "=d" (owner) : "Q" (*lock) : "memory");
+ return owner;
+}
+
+static inline int arch_cmpxchg_niai8(int *lock, int old, int new)
+{
+ int expected = old;
+
+ asm_inline volatile(
+ ALTERNATIVE("nop", ".insn rre,0xb2fa0000,8,0", 49) /* NIAI 8 */
+ " cs %0,%3,%1\n"
+ : "=d" (old), "=Q" (*lock)
+ : "0" (old), "d" (new), "Q" (*lock)
+ : "cc", "memory");
+ return expected == old;
+}
+
+static inline struct spin_wait *arch_spin_decode_tail(int lock)
+{
+ int ix, cpu;
+
+ ix = (lock & _Q_TAIL_IDX_MASK) >> _Q_TAIL_IDX_OFFSET;
+ cpu = (lock & _Q_TAIL_CPU_MASK) >> _Q_TAIL_CPU_OFFSET;
+ return per_cpu_ptr(&spin_wait[ix], cpu - 1);
+}
+
+static inline int arch_spin_yield_target(int lock, struct spin_wait *node)
+{
+ if (lock & _Q_LOCK_CPU_MASK)
+ return lock & _Q_LOCK_CPU_MASK;
+ if (node == NULL || node->prev == NULL)
+ return 0; /* 0 -> no target cpu */
+ while (node->prev)
+ node = node->prev;
+ return node->node_id >> _Q_TAIL_CPU_OFFSET;
+}
+
+static inline void arch_spin_lock_queued(arch_spinlock_t *lp)
+{
+ struct spin_wait *node, *next;
+ int lockval, ix, node_id, tail_id, old, new, owner, count;
+
+ ix = S390_lowcore.spinlock_index++;
+ barrier();
+ lockval = SPINLOCK_LOCKVAL; /* cpu + 1 */
+ node = this_cpu_ptr(&spin_wait[ix]);
+ node->prev = node->next = NULL;
+ node_id = node->node_id;
+
+ /* Enqueue the node for this CPU in the spinlock wait queue */
+ while (1) {
+ old = READ_ONCE(lp->lock);
+ if ((old & _Q_LOCK_CPU_MASK) == 0 &&
+ (old & _Q_LOCK_STEAL_MASK) != _Q_LOCK_STEAL_MASK) {
+ /*
+ * The lock is free but there may be waiters.
+ * With no waiters simply take the lock, if there
+ * are waiters try to steal the lock. The lock may
+ * be stolen three times before the next queued
+ * waiter will get the lock.
+ */
+ new = (old ? (old + _Q_LOCK_STEAL_ADD) : 0) | lockval;
+ if (__atomic_cmpxchg_bool(&lp->lock, old, new))
+ /* Got the lock */
+ goto out;
+ /* lock passing in progress */
+ continue;
+ }
+ /* Make the node of this CPU the new tail. */
+ new = node_id | (old & _Q_LOCK_MASK);
+ if (__atomic_cmpxchg_bool(&lp->lock, old, new))
+ break;
+ }
+ /* Set the 'next' pointer of the tail node in the queue */
+ tail_id = old & _Q_TAIL_MASK;
+ if (tail_id != 0) {
+ node->prev = arch_spin_decode_tail(tail_id);
+ WRITE_ONCE(node->prev->next, node);
+ }
+
+ /* Pass the virtual CPU to the lock holder if it is not running */
+ owner = arch_spin_yield_target(old, node);
+ if (owner && arch_vcpu_is_preempted(owner - 1))
+ smp_yield_cpu(owner - 1);
+
+ /* Spin on the CPU local node->prev pointer */
+ if (tail_id != 0) {
+ count = spin_retry;
+ while (READ_ONCE(node->prev) != NULL) {
+ if (count-- >= 0)
+ continue;
+ count = spin_retry;
+ /* Query running state of lock holder again. */
+ owner = arch_spin_yield_target(old, node);
+ if (owner && arch_vcpu_is_preempted(owner - 1))
+ smp_yield_cpu(owner - 1);
+ }
+ }
+
+ /* Spin on the lock value in the spinlock_t */
+ count = spin_retry;
+ while (1) {
+ old = READ_ONCE(lp->lock);
+ owner = old & _Q_LOCK_CPU_MASK;
+ if (!owner) {
+ tail_id = old & _Q_TAIL_MASK;
+ new = ((tail_id != node_id) ? tail_id : 0) | lockval;
+ if (__atomic_cmpxchg_bool(&lp->lock, old, new))
+ /* Got the lock */
+ break;
+ continue;
+ }
+ if (count-- >= 0)
+ continue;
+ count = spin_retry;
+ if (!MACHINE_IS_LPAR || arch_vcpu_is_preempted(owner - 1))
+ smp_yield_cpu(owner - 1);
+ }
+
+ /* Pass lock_spin job to next CPU in the queue */
+ if (node_id && tail_id != node_id) {
+ /* Wait until the next CPU has set up the 'next' pointer */
+ while ((next = READ_ONCE(node->next)) == NULL)
+ ;
+ next->prev = NULL;
+ }
+
+ out:
+ S390_lowcore.spinlock_index--;
+}
+
+static inline void arch_spin_lock_classic(arch_spinlock_t *lp)
+{
+ int lockval, old, new, owner, count;
+
+ lockval = SPINLOCK_LOCKVAL; /* cpu + 1 */
+
+ /* Pass the virtual CPU to the lock holder if it is not running */
+ owner = arch_spin_yield_target(READ_ONCE(lp->lock), NULL);
+ if (owner && arch_vcpu_is_preempted(owner - 1))
+ smp_yield_cpu(owner - 1);
+
+ count = spin_retry;
+ while (1) {
+ old = arch_load_niai4(&lp->lock);
+ owner = old & _Q_LOCK_CPU_MASK;
+ /* Try to get the lock if it is free. */
+ if (!owner) {
+ new = (old & _Q_TAIL_MASK) | lockval;
+ if (arch_cmpxchg_niai8(&lp->lock, old, new)) {
+ /* Got the lock */
+ return;
+ }
+ continue;
+ }
+ if (count-- >= 0)
+ continue;
+ count = spin_retry;
+ if (!MACHINE_IS_LPAR || arch_vcpu_is_preempted(owner - 1))
+ smp_yield_cpu(owner - 1);
+ }
+}
+
+void arch_spin_lock_wait(arch_spinlock_t *lp)
+{
+ if (test_cpu_flag(CIF_DEDICATED_CPU))
+ arch_spin_lock_queued(lp);
+ else
+ arch_spin_lock_classic(lp);
+}
+EXPORT_SYMBOL(arch_spin_lock_wait);
+
+int arch_spin_trylock_retry(arch_spinlock_t *lp)
+{
+ int cpu = SPINLOCK_LOCKVAL;
+ int owner, count;
+
+ for (count = spin_retry; count > 0; count--) {
+ owner = READ_ONCE(lp->lock);
+ /* Try to get the lock if it is free. */
+ if (!owner) {
+ if (__atomic_cmpxchg_bool(&lp->lock, 0, cpu))
+ return 1;
+ }
+ }
+ return 0;
+}
+EXPORT_SYMBOL(arch_spin_trylock_retry);
+
+void arch_read_lock_wait(arch_rwlock_t *rw)
+{
+ if (unlikely(in_interrupt())) {
+ while (READ_ONCE(rw->cnts) & 0x10000)
+ barrier();
+ return;
+ }
+
+ /* Remove this reader again to allow recursive read locking */
+ __atomic_add_const(-1, &rw->cnts);
+ /* Put the reader into the wait queue */
+ arch_spin_lock(&rw->wait);
+ /* Now add this reader to the count value again */
+ __atomic_add_const(1, &rw->cnts);
+ /* Loop until the writer is done */
+ while (READ_ONCE(rw->cnts) & 0x10000)
+ barrier();
+ arch_spin_unlock(&rw->wait);
+}
+EXPORT_SYMBOL(arch_read_lock_wait);
+
+void arch_write_lock_wait(arch_rwlock_t *rw)
+{
+ int old;
+
+ /* Add this CPU to the write waiters */
+ __atomic_add(0x20000, &rw->cnts);
+
+ /* Put the writer into the wait queue */
+ arch_spin_lock(&rw->wait);
+
+ while (1) {
+ old = READ_ONCE(rw->cnts);
+ if ((old & 0x1ffff) == 0 &&
+ __atomic_cmpxchg_bool(&rw->cnts, old, old | 0x10000))
+ /* Got the lock */
+ break;
+ barrier();
+ }
+
+ arch_spin_unlock(&rw->wait);
+}
+EXPORT_SYMBOL(arch_write_lock_wait);
+
+void arch_spin_relax(arch_spinlock_t *lp)
+{
+ int cpu;
+
+ cpu = READ_ONCE(lp->lock) & _Q_LOCK_CPU_MASK;
+ if (!cpu)
+ return;
+ if (MACHINE_IS_LPAR && !arch_vcpu_is_preempted(cpu - 1))
+ return;
+ smp_yield_cpu(cpu - 1);
+}
+EXPORT_SYMBOL(arch_spin_relax);