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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/arm/kernel/smp.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 'arch/arm/kernel/smp.c')
-rw-r--r--arch/arm/kernel/smp.c855
1 files changed, 855 insertions, 0 deletions
diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c
new file mode 100644
index 000000000..0b8c25763
--- /dev/null
+++ b/arch/arm/kernel/smp.c
@@ -0,0 +1,855 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * linux/arch/arm/kernel/smp.c
+ *
+ * Copyright (C) 2002 ARM Limited, All Rights Reserved.
+ */
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/spinlock.h>
+#include <linux/sched/mm.h>
+#include <linux/sched/hotplug.h>
+#include <linux/sched/task_stack.h>
+#include <linux/interrupt.h>
+#include <linux/cache.h>
+#include <linux/profile.h>
+#include <linux/errno.h>
+#include <linux/mm.h>
+#include <linux/err.h>
+#include <linux/cpu.h>
+#include <linux/seq_file.h>
+#include <linux/irq.h>
+#include <linux/nmi.h>
+#include <linux/percpu.h>
+#include <linux/clockchips.h>
+#include <linux/completion.h>
+#include <linux/cpufreq.h>
+#include <linux/irq_work.h>
+#include <linux/kernel_stat.h>
+
+#include <linux/atomic.h>
+#include <asm/bugs.h>
+#include <asm/smp.h>
+#include <asm/cacheflush.h>
+#include <asm/cpu.h>
+#include <asm/cputype.h>
+#include <asm/exception.h>
+#include <asm/idmap.h>
+#include <asm/topology.h>
+#include <asm/mmu_context.h>
+#include <asm/procinfo.h>
+#include <asm/processor.h>
+#include <asm/sections.h>
+#include <asm/tlbflush.h>
+#include <asm/ptrace.h>
+#include <asm/smp_plat.h>
+#include <asm/virt.h>
+#include <asm/mach/arch.h>
+#include <asm/mpu.h>
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/ipi.h>
+
+/*
+ * as from 2.5, kernels no longer have an init_tasks structure
+ * so we need some other way of telling a new secondary core
+ * where to place its SVC stack
+ */
+struct secondary_data secondary_data;
+
+enum ipi_msg_type {
+ IPI_WAKEUP,
+ IPI_TIMER,
+ IPI_RESCHEDULE,
+ IPI_CALL_FUNC,
+ IPI_CPU_STOP,
+ IPI_IRQ_WORK,
+ IPI_COMPLETION,
+ NR_IPI,
+ /*
+ * CPU_BACKTRACE is special and not included in NR_IPI
+ * or tracable with trace_ipi_*
+ */
+ IPI_CPU_BACKTRACE = NR_IPI,
+ /*
+ * SGI8-15 can be reserved by secure firmware, and thus may
+ * not be usable by the kernel. Please keep the above limited
+ * to at most 8 entries.
+ */
+ MAX_IPI
+};
+
+static int ipi_irq_base __read_mostly;
+static int nr_ipi __read_mostly = NR_IPI;
+static struct irq_desc *ipi_desc[MAX_IPI] __read_mostly;
+
+static void ipi_setup(int cpu);
+
+static DECLARE_COMPLETION(cpu_running);
+
+static struct smp_operations smp_ops __ro_after_init;
+
+void __init smp_set_ops(const struct smp_operations *ops)
+{
+ if (ops)
+ smp_ops = *ops;
+};
+
+static unsigned long get_arch_pgd(pgd_t *pgd)
+{
+#ifdef CONFIG_ARM_LPAE
+ return __phys_to_pfn(virt_to_phys(pgd));
+#else
+ return virt_to_phys(pgd);
+#endif
+}
+
+#if defined(CONFIG_BIG_LITTLE) && defined(CONFIG_HARDEN_BRANCH_PREDICTOR)
+static int secondary_biglittle_prepare(unsigned int cpu)
+{
+ if (!cpu_vtable[cpu])
+ cpu_vtable[cpu] = kzalloc(sizeof(*cpu_vtable[cpu]), GFP_KERNEL);
+
+ return cpu_vtable[cpu] ? 0 : -ENOMEM;
+}
+
+static void secondary_biglittle_init(void)
+{
+ init_proc_vtable(lookup_processor(read_cpuid_id())->proc);
+}
+#else
+static int secondary_biglittle_prepare(unsigned int cpu)
+{
+ return 0;
+}
+
+static void secondary_biglittle_init(void)
+{
+}
+#endif
+
+int __cpu_up(unsigned int cpu, struct task_struct *idle)
+{
+ int ret;
+
+ if (!smp_ops.smp_boot_secondary)
+ return -ENOSYS;
+
+ ret = secondary_biglittle_prepare(cpu);
+ if (ret)
+ return ret;
+
+ /*
+ * We need to tell the secondary core where to find
+ * its stack and the page tables.
+ */
+ secondary_data.stack = task_stack_page(idle) + THREAD_START_SP;
+#ifdef CONFIG_ARM_MPU
+ secondary_data.mpu_rgn_info = &mpu_rgn_info;
+#endif
+
+#ifdef CONFIG_MMU
+ secondary_data.pgdir = virt_to_phys(idmap_pgd);
+ secondary_data.swapper_pg_dir = get_arch_pgd(swapper_pg_dir);
+#endif
+ secondary_data.task = idle;
+ sync_cache_w(&secondary_data);
+
+ /*
+ * Now bring the CPU into our world.
+ */
+ ret = smp_ops.smp_boot_secondary(cpu, idle);
+ if (ret == 0) {
+ /*
+ * CPU was successfully started, wait for it
+ * to come online or time out.
+ */
+ wait_for_completion_timeout(&cpu_running,
+ msecs_to_jiffies(1000));
+
+ if (!cpu_online(cpu)) {
+ pr_crit("CPU%u: failed to come online\n", cpu);
+ ret = -EIO;
+ }
+ } else {
+ pr_err("CPU%u: failed to boot: %d\n", cpu, ret);
+ }
+
+
+ memset(&secondary_data, 0, sizeof(secondary_data));
+ return ret;
+}
+
+/* platform specific SMP operations */
+void __init smp_init_cpus(void)
+{
+ if (smp_ops.smp_init_cpus)
+ smp_ops.smp_init_cpus();
+}
+
+int platform_can_secondary_boot(void)
+{
+ return !!smp_ops.smp_boot_secondary;
+}
+
+int platform_can_cpu_hotplug(void)
+{
+#ifdef CONFIG_HOTPLUG_CPU
+ if (smp_ops.cpu_kill)
+ return 1;
+#endif
+
+ return 0;
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+static int platform_cpu_kill(unsigned int cpu)
+{
+ if (smp_ops.cpu_kill)
+ return smp_ops.cpu_kill(cpu);
+ return 1;
+}
+
+static int platform_cpu_disable(unsigned int cpu)
+{
+ if (smp_ops.cpu_disable)
+ return smp_ops.cpu_disable(cpu);
+
+ return 0;
+}
+
+int platform_can_hotplug_cpu(unsigned int cpu)
+{
+ /* cpu_die must be specified to support hotplug */
+ if (!smp_ops.cpu_die)
+ return 0;
+
+ if (smp_ops.cpu_can_disable)
+ return smp_ops.cpu_can_disable(cpu);
+
+ /*
+ * By default, allow disabling all CPUs except the first one,
+ * since this is special on a lot of platforms, e.g. because
+ * of clock tick interrupts.
+ */
+ return cpu != 0;
+}
+
+static void ipi_teardown(int cpu)
+{
+ int i;
+
+ if (WARN_ON_ONCE(!ipi_irq_base))
+ return;
+
+ for (i = 0; i < nr_ipi; i++)
+ disable_percpu_irq(ipi_irq_base + i);
+}
+
+/*
+ * __cpu_disable runs on the processor to be shutdown.
+ */
+int __cpu_disable(void)
+{
+ unsigned int cpu = smp_processor_id();
+ int ret;
+
+ ret = platform_cpu_disable(cpu);
+ if (ret)
+ return ret;
+
+#ifdef CONFIG_GENERIC_ARCH_TOPOLOGY
+ remove_cpu_topology(cpu);
+#endif
+
+ /*
+ * Take this CPU offline. Once we clear this, we can't return,
+ * and we must not schedule until we're ready to give up the cpu.
+ */
+ set_cpu_online(cpu, false);
+ ipi_teardown(cpu);
+
+ /*
+ * OK - migrate IRQs away from this CPU
+ */
+ irq_migrate_all_off_this_cpu();
+
+ /*
+ * Flush user cache and TLB mappings, and then remove this CPU
+ * from the vm mask set of all processes.
+ *
+ * Caches are flushed to the Level of Unification Inner Shareable
+ * to write-back dirty lines to unified caches shared by all CPUs.
+ */
+ flush_cache_louis();
+ local_flush_tlb_all();
+
+ return 0;
+}
+
+/*
+ * called on the thread which is asking for a CPU to be shutdown -
+ * waits until shutdown has completed, or it is timed out.
+ */
+void __cpu_die(unsigned int cpu)
+{
+ if (!cpu_wait_death(cpu, 5)) {
+ pr_err("CPU%u: cpu didn't die\n", cpu);
+ return;
+ }
+ pr_debug("CPU%u: shutdown\n", cpu);
+
+ clear_tasks_mm_cpumask(cpu);
+ /*
+ * platform_cpu_kill() is generally expected to do the powering off
+ * and/or cutting of clocks to the dying CPU. Optionally, this may
+ * be done by the CPU which is dying in preference to supporting
+ * this call, but that means there is _no_ synchronisation between
+ * the requesting CPU and the dying CPU actually losing power.
+ */
+ if (!platform_cpu_kill(cpu))
+ pr_err("CPU%u: unable to kill\n", cpu);
+}
+
+/*
+ * Called from the idle thread for the CPU which has been shutdown.
+ *
+ * Note that we disable IRQs here, but do not re-enable them
+ * before returning to the caller. This is also the behaviour
+ * of the other hotplug-cpu capable cores, so presumably coming
+ * out of idle fixes this.
+ */
+void arch_cpu_idle_dead(void)
+{
+ unsigned int cpu = smp_processor_id();
+
+ idle_task_exit();
+
+ local_irq_disable();
+
+ /*
+ * Flush the data out of the L1 cache for this CPU. This must be
+ * before the completion to ensure that data is safely written out
+ * before platform_cpu_kill() gets called - which may disable
+ * *this* CPU and power down its cache.
+ */
+ flush_cache_louis();
+
+ /*
+ * Tell __cpu_die() that this CPU is now safe to dispose of. Once
+ * this returns, power and/or clocks can be removed at any point
+ * from this CPU and its cache by platform_cpu_kill().
+ */
+ (void)cpu_report_death();
+
+ /*
+ * Ensure that the cache lines associated with that completion are
+ * written out. This covers the case where _this_ CPU is doing the
+ * powering down, to ensure that the completion is visible to the
+ * CPU waiting for this one.
+ */
+ flush_cache_louis();
+
+ /*
+ * The actual CPU shutdown procedure is at least platform (if not
+ * CPU) specific. This may remove power, or it may simply spin.
+ *
+ * Platforms are generally expected *NOT* to return from this call,
+ * although there are some which do because they have no way to
+ * power down the CPU. These platforms are the _only_ reason we
+ * have a return path which uses the fragment of assembly below.
+ *
+ * The return path should not be used for platforms which can
+ * power off the CPU.
+ */
+ if (smp_ops.cpu_die)
+ smp_ops.cpu_die(cpu);
+
+ pr_warn("CPU%u: smp_ops.cpu_die() returned, trying to resuscitate\n",
+ cpu);
+
+ /*
+ * Do not return to the idle loop - jump back to the secondary
+ * cpu initialisation. There's some initialisation which needs
+ * to be repeated to undo the effects of taking the CPU offline.
+ */
+ __asm__("mov sp, %0\n"
+ " mov fp, #0\n"
+ " mov r0, %1\n"
+ " b secondary_start_kernel"
+ :
+ : "r" (task_stack_page(current) + THREAD_SIZE - 8),
+ "r" (current)
+ : "r0");
+}
+#endif /* CONFIG_HOTPLUG_CPU */
+
+/*
+ * Called by both boot and secondaries to move global data into
+ * per-processor storage.
+ */
+static void smp_store_cpu_info(unsigned int cpuid)
+{
+ struct cpuinfo_arm *cpu_info = &per_cpu(cpu_data, cpuid);
+
+ cpu_info->loops_per_jiffy = loops_per_jiffy;
+ cpu_info->cpuid = read_cpuid_id();
+
+ store_cpu_topology(cpuid);
+ check_cpu_icache_size(cpuid);
+}
+
+static void set_current(struct task_struct *cur)
+{
+ /* Set TPIDRURO */
+ asm("mcr p15, 0, %0, c13, c0, 3" :: "r"(cur) : "memory");
+}
+
+/*
+ * This is the secondary CPU boot entry. We're using this CPUs
+ * idle thread stack, but a set of temporary page tables.
+ */
+asmlinkage void secondary_start_kernel(struct task_struct *task)
+{
+ struct mm_struct *mm = &init_mm;
+ unsigned int cpu;
+
+ set_current(task);
+
+ secondary_biglittle_init();
+
+ /*
+ * The identity mapping is uncached (strongly ordered), so
+ * switch away from it before attempting any exclusive accesses.
+ */
+ cpu_switch_mm(mm->pgd, mm);
+ local_flush_bp_all();
+ enter_lazy_tlb(mm, current);
+ local_flush_tlb_all();
+
+ /*
+ * All kernel threads share the same mm context; grab a
+ * reference and switch to it.
+ */
+ cpu = smp_processor_id();
+ mmgrab(mm);
+ current->active_mm = mm;
+ cpumask_set_cpu(cpu, mm_cpumask(mm));
+
+ cpu_init();
+
+#ifndef CONFIG_MMU
+ setup_vectors_base();
+#endif
+ pr_debug("CPU%u: Booted secondary processor\n", cpu);
+
+ trace_hardirqs_off();
+
+ /*
+ * Give the platform a chance to do its own initialisation.
+ */
+ if (smp_ops.smp_secondary_init)
+ smp_ops.smp_secondary_init(cpu);
+
+ notify_cpu_starting(cpu);
+
+ ipi_setup(cpu);
+
+ calibrate_delay();
+
+ smp_store_cpu_info(cpu);
+
+ /*
+ * OK, now it's safe to let the boot CPU continue. Wait for
+ * the CPU migration code to notice that the CPU is online
+ * before we continue - which happens after __cpu_up returns.
+ */
+ set_cpu_online(cpu, true);
+
+ check_other_bugs();
+
+ complete(&cpu_running);
+
+ local_irq_enable();
+ local_fiq_enable();
+ local_abt_enable();
+
+ /*
+ * OK, it's off to the idle thread for us
+ */
+ cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
+}
+
+void __init smp_cpus_done(unsigned int max_cpus)
+{
+ int cpu;
+ unsigned long bogosum = 0;
+
+ for_each_online_cpu(cpu)
+ bogosum += per_cpu(cpu_data, cpu).loops_per_jiffy;
+
+ printk(KERN_INFO "SMP: Total of %d processors activated "
+ "(%lu.%02lu BogoMIPS).\n",
+ num_online_cpus(),
+ bogosum / (500000/HZ),
+ (bogosum / (5000/HZ)) % 100);
+
+ hyp_mode_check();
+}
+
+void __init smp_prepare_boot_cpu(void)
+{
+ set_my_cpu_offset(per_cpu_offset(smp_processor_id()));
+}
+
+void __init smp_prepare_cpus(unsigned int max_cpus)
+{
+ unsigned int ncores = num_possible_cpus();
+
+ init_cpu_topology();
+
+ smp_store_cpu_info(smp_processor_id());
+
+ /*
+ * are we trying to boot more cores than exist?
+ */
+ if (max_cpus > ncores)
+ max_cpus = ncores;
+ if (ncores > 1 && max_cpus) {
+ /*
+ * Initialise the present map, which describes the set of CPUs
+ * actually populated at the present time. A platform should
+ * re-initialize the map in the platforms smp_prepare_cpus()
+ * if present != possible (e.g. physical hotplug).
+ */
+ init_cpu_present(cpu_possible_mask);
+
+ /*
+ * Initialise the SCU if there are more than one CPU
+ * and let them know where to start.
+ */
+ if (smp_ops.smp_prepare_cpus)
+ smp_ops.smp_prepare_cpus(max_cpus);
+ }
+}
+
+static const char *ipi_types[NR_IPI] __tracepoint_string = {
+ [IPI_WAKEUP] = "CPU wakeup interrupts",
+ [IPI_TIMER] = "Timer broadcast interrupts",
+ [IPI_RESCHEDULE] = "Rescheduling interrupts",
+ [IPI_CALL_FUNC] = "Function call interrupts",
+ [IPI_CPU_STOP] = "CPU stop interrupts",
+ [IPI_IRQ_WORK] = "IRQ work interrupts",
+ [IPI_COMPLETION] = "completion interrupts",
+};
+
+static void smp_cross_call(const struct cpumask *target, unsigned int ipinr);
+
+void show_ipi_list(struct seq_file *p, int prec)
+{
+ unsigned int cpu, i;
+
+ for (i = 0; i < NR_IPI; i++) {
+ if (!ipi_desc[i])
+ continue;
+
+ seq_printf(p, "%*s%u: ", prec - 1, "IPI", i);
+
+ for_each_online_cpu(cpu)
+ seq_printf(p, "%10u ", irq_desc_kstat_cpu(ipi_desc[i], cpu));
+
+ seq_printf(p, " %s\n", ipi_types[i]);
+ }
+}
+
+void arch_send_call_function_ipi_mask(const struct cpumask *mask)
+{
+ smp_cross_call(mask, IPI_CALL_FUNC);
+}
+
+void arch_send_wakeup_ipi_mask(const struct cpumask *mask)
+{
+ smp_cross_call(mask, IPI_WAKEUP);
+}
+
+void arch_send_call_function_single_ipi(int cpu)
+{
+ smp_cross_call(cpumask_of(cpu), IPI_CALL_FUNC);
+}
+
+#ifdef CONFIG_IRQ_WORK
+void arch_irq_work_raise(void)
+{
+ if (arch_irq_work_has_interrupt())
+ smp_cross_call(cpumask_of(smp_processor_id()), IPI_IRQ_WORK);
+}
+#endif
+
+#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
+void tick_broadcast(const struct cpumask *mask)
+{
+ smp_cross_call(mask, IPI_TIMER);
+}
+#endif
+
+static DEFINE_RAW_SPINLOCK(stop_lock);
+
+/*
+ * ipi_cpu_stop - handle IPI from smp_send_stop()
+ */
+static void ipi_cpu_stop(unsigned int cpu)
+{
+ local_fiq_disable();
+
+ if (system_state <= SYSTEM_RUNNING) {
+ raw_spin_lock(&stop_lock);
+ pr_crit("CPU%u: stopping\n", cpu);
+ dump_stack();
+ raw_spin_unlock(&stop_lock);
+ }
+
+ set_cpu_online(cpu, false);
+
+ while (1) {
+ cpu_relax();
+ wfe();
+ }
+}
+
+static DEFINE_PER_CPU(struct completion *, cpu_completion);
+
+int register_ipi_completion(struct completion *completion, int cpu)
+{
+ per_cpu(cpu_completion, cpu) = completion;
+ return IPI_COMPLETION;
+}
+
+static void ipi_complete(unsigned int cpu)
+{
+ complete(per_cpu(cpu_completion, cpu));
+}
+
+/*
+ * Main handler for inter-processor interrupts
+ */
+static void do_handle_IPI(int ipinr)
+{
+ unsigned int cpu = smp_processor_id();
+
+ if ((unsigned)ipinr < NR_IPI)
+ trace_ipi_entry(ipi_types[ipinr]);
+
+ switch (ipinr) {
+ case IPI_WAKEUP:
+ break;
+
+#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
+ case IPI_TIMER:
+ tick_receive_broadcast();
+ break;
+#endif
+
+ case IPI_RESCHEDULE:
+ scheduler_ipi();
+ break;
+
+ case IPI_CALL_FUNC:
+ generic_smp_call_function_interrupt();
+ break;
+
+ case IPI_CPU_STOP:
+ ipi_cpu_stop(cpu);
+ break;
+
+#ifdef CONFIG_IRQ_WORK
+ case IPI_IRQ_WORK:
+ irq_work_run();
+ break;
+#endif
+
+ case IPI_COMPLETION:
+ ipi_complete(cpu);
+ break;
+
+ case IPI_CPU_BACKTRACE:
+ printk_deferred_enter();
+ nmi_cpu_backtrace(get_irq_regs());
+ printk_deferred_exit();
+ break;
+
+ default:
+ pr_crit("CPU%u: Unknown IPI message 0x%x\n",
+ cpu, ipinr);
+ break;
+ }
+
+ if ((unsigned)ipinr < NR_IPI)
+ trace_ipi_exit(ipi_types[ipinr]);
+}
+
+/* Legacy version, should go away once all irqchips have been converted */
+void handle_IPI(int ipinr, struct pt_regs *regs)
+{
+ struct pt_regs *old_regs = set_irq_regs(regs);
+
+ irq_enter();
+ do_handle_IPI(ipinr);
+ irq_exit();
+
+ set_irq_regs(old_regs);
+}
+
+static irqreturn_t ipi_handler(int irq, void *data)
+{
+ do_handle_IPI(irq - ipi_irq_base);
+ return IRQ_HANDLED;
+}
+
+static void smp_cross_call(const struct cpumask *target, unsigned int ipinr)
+{
+ trace_ipi_raise(target, ipi_types[ipinr]);
+ __ipi_send_mask(ipi_desc[ipinr], target);
+}
+
+static void ipi_setup(int cpu)
+{
+ int i;
+
+ if (WARN_ON_ONCE(!ipi_irq_base))
+ return;
+
+ for (i = 0; i < nr_ipi; i++)
+ enable_percpu_irq(ipi_irq_base + i, 0);
+}
+
+void __init set_smp_ipi_range(int ipi_base, int n)
+{
+ int i;
+
+ WARN_ON(n < MAX_IPI);
+ nr_ipi = min(n, MAX_IPI);
+
+ for (i = 0; i < nr_ipi; i++) {
+ int err;
+
+ err = request_percpu_irq(ipi_base + i, ipi_handler,
+ "IPI", &irq_stat);
+ WARN_ON(err);
+
+ ipi_desc[i] = irq_to_desc(ipi_base + i);
+ irq_set_status_flags(ipi_base + i, IRQ_HIDDEN);
+ }
+
+ ipi_irq_base = ipi_base;
+
+ /* Setup the boot CPU immediately */
+ ipi_setup(smp_processor_id());
+}
+
+void smp_send_reschedule(int cpu)
+{
+ smp_cross_call(cpumask_of(cpu), IPI_RESCHEDULE);
+}
+
+void smp_send_stop(void)
+{
+ unsigned long timeout;
+ struct cpumask mask;
+
+ cpumask_copy(&mask, cpu_online_mask);
+ cpumask_clear_cpu(smp_processor_id(), &mask);
+ if (!cpumask_empty(&mask))
+ smp_cross_call(&mask, IPI_CPU_STOP);
+
+ /* Wait up to one second for other CPUs to stop */
+ timeout = USEC_PER_SEC;
+ while (num_online_cpus() > 1 && timeout--)
+ udelay(1);
+
+ if (num_online_cpus() > 1)
+ pr_warn("SMP: failed to stop secondary CPUs\n");
+}
+
+/* In case panic() and panic() called at the same time on CPU1 and CPU2,
+ * and CPU 1 calls panic_smp_self_stop() before crash_smp_send_stop()
+ * CPU1 can't receive the ipi irqs from CPU2, CPU1 will be always online,
+ * kdump fails. So split out the panic_smp_self_stop() and add
+ * set_cpu_online(smp_processor_id(), false).
+ */
+void panic_smp_self_stop(void)
+{
+ pr_debug("CPU %u will stop doing anything useful since another CPU has paniced\n",
+ smp_processor_id());
+ set_cpu_online(smp_processor_id(), false);
+ while (1)
+ cpu_relax();
+}
+
+#ifdef CONFIG_CPU_FREQ
+
+static DEFINE_PER_CPU(unsigned long, l_p_j_ref);
+static DEFINE_PER_CPU(unsigned long, l_p_j_ref_freq);
+static unsigned long global_l_p_j_ref;
+static unsigned long global_l_p_j_ref_freq;
+
+static int cpufreq_callback(struct notifier_block *nb,
+ unsigned long val, void *data)
+{
+ struct cpufreq_freqs *freq = data;
+ struct cpumask *cpus = freq->policy->cpus;
+ int cpu, first = cpumask_first(cpus);
+ unsigned int lpj;
+
+ if (freq->flags & CPUFREQ_CONST_LOOPS)
+ return NOTIFY_OK;
+
+ if (!per_cpu(l_p_j_ref, first)) {
+ for_each_cpu(cpu, cpus) {
+ per_cpu(l_p_j_ref, cpu) =
+ per_cpu(cpu_data, cpu).loops_per_jiffy;
+ per_cpu(l_p_j_ref_freq, cpu) = freq->old;
+ }
+
+ if (!global_l_p_j_ref) {
+ global_l_p_j_ref = loops_per_jiffy;
+ global_l_p_j_ref_freq = freq->old;
+ }
+ }
+
+ if ((val == CPUFREQ_PRECHANGE && freq->old < freq->new) ||
+ (val == CPUFREQ_POSTCHANGE && freq->old > freq->new)) {
+ loops_per_jiffy = cpufreq_scale(global_l_p_j_ref,
+ global_l_p_j_ref_freq,
+ freq->new);
+
+ lpj = cpufreq_scale(per_cpu(l_p_j_ref, first),
+ per_cpu(l_p_j_ref_freq, first), freq->new);
+ for_each_cpu(cpu, cpus)
+ per_cpu(cpu_data, cpu).loops_per_jiffy = lpj;
+ }
+ return NOTIFY_OK;
+}
+
+static struct notifier_block cpufreq_notifier = {
+ .notifier_call = cpufreq_callback,
+};
+
+static int __init register_cpufreq_notifier(void)
+{
+ return cpufreq_register_notifier(&cpufreq_notifier,
+ CPUFREQ_TRANSITION_NOTIFIER);
+}
+core_initcall(register_cpufreq_notifier);
+
+#endif
+
+static void raise_nmi(cpumask_t *mask)
+{
+ __ipi_send_mask(ipi_desc[IPI_CPU_BACKTRACE], mask);
+}
+
+void arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self)
+{
+ nmi_trigger_cpumask_backtrace(mask, exclude_self, raise_nmi);
+}