cregit-Linux how code gets into the kernel

Release 4.8 arch/powerpc/kvm/book3s_hv_builtin.c

Directory: arch/powerpc/kvm
/*
 * Copyright 2011 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License, version 2, as
 * published by the Free Software Foundation.
 */

#include <linux/cpu.h>
#include <linux/kvm_host.h>
#include <linux/preempt.h>
#include <linux/export.h>
#include <linux/sched.h>
#include <linux/spinlock.h>
#include <linux/init.h>
#include <linux/memblock.h>
#include <linux/sizes.h>
#include <linux/cma.h>
#include <linux/bitops.h>

#include <asm/cputable.h>
#include <asm/kvm_ppc.h>
#include <asm/kvm_book3s.h>
#include <asm/archrandom.h>
#include <asm/xics.h>
#include <asm/dbell.h>
#include <asm/cputhreads.h>


#define KVM_CMA_CHUNK_ORDER	18

/*
 * Hash page table alignment on newer cpus(CPU_FTR_ARCH_206)
 * should be power of 2.
 */

#define HPT_ALIGN_PAGES		((1 << 18) >> PAGE_SHIFT) 
/* 256k */
/*
 * By default we reserve 5% of memory for hash pagetable allocation.
 */

static unsigned long kvm_cma_resv_ratio = 5;


static struct cma *kvm_cma;


static int __init early_parse_kvm_cma_resv(char *p) { pr_debug("%s(%s)\n", __func__, p); if (!p) return -EINVAL; return kstrtoul(p, 0, &kvm_cma_resv_ratio); }

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alexander grafalexander graf2357.50%150.00%
aneesh kumaraneesh kumar1742.50%150.00%
Total40100.00%2100.00%

early_param("kvm_cma_resv_ratio", early_parse_kvm_cma_resv);
struct page *kvm_alloc_hpt(unsigned long nr_pages) { VM_BUG_ON(order_base_2(nr_pages) < KVM_CMA_CHUNK_ORDER - PAGE_SHIFT); return cma_alloc(kvm_cma, nr_pages, order_base_2(HPT_ALIGN_PAGES)); }

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joonsoo kimjoonsoo kim1644.44%120.00%
alexander grafalexander graf1130.56%120.00%
aneesh kumaraneesh kumar616.67%120.00%
alexey kardashevskiyalexey kardashevskiy25.56%120.00%
paul mackerraspaul mackerras12.78%120.00%
Total36100.00%5100.00%

EXPORT_SYMBOL_GPL(kvm_alloc_hpt);
void kvm_release_hpt(struct page *page, unsigned long nr_pages) { cma_release(kvm_cma, page, nr_pages); }

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alexander grafalexander graf1147.83%133.33%
aneesh kumaraneesh kumar939.13%133.33%
joonsoo kimjoonsoo kim313.04%133.33%
Total23100.00%3100.00%

EXPORT_SYMBOL_GPL(kvm_release_hpt); /** * kvm_cma_reserve() - reserve area for kvm hash pagetable * * This function reserves memory from early allocator. It should be * called by arch specific code once the memblock allocator * has been activated and all other subsystems have already allocated/reserved * memory. */
void __init kvm_cma_reserve(void) { unsigned long align_size; struct memblock_region *reg; phys_addr_t selected_size = 0; /* * We need CMA reservation only when we are in HV mode */ if (!cpu_has_feature(CPU_FTR_HVMODE)) return; /* * We cannot use memblock_phys_mem_size() here, because * memblock_analyze() has not been called yet. */ for_each_memblock(memory, reg) selected_size += memblock_region_memory_end_pfn(reg) - memblock_region_memory_base_pfn(reg); selected_size = (selected_size * kvm_cma_resv_ratio / 100) << PAGE_SHIFT; if (selected_size) { pr_debug("%s: reserving %ld MiB for global area\n", __func__, (unsigned long)selected_size / SZ_1M); align_size = HPT_ALIGN_PAGES << PAGE_SHIFT; cma_declare_contiguous(0, selected_size, 0, align_size, KVM_CMA_CHUNK_ORDER - PAGE_SHIFT, false, &kvm_cma); } }

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aneesh kumaraneesh kumar9485.45%250.00%
joonsoo kimjoonsoo kim1614.55%250.00%
Total110100.00%4100.00%

/* * Real-mode H_CONFER implementation. * We check if we are the only vcpu out of this virtual core * still running in the guest and not ceded. If so, we pop up * to the virtual-mode implementation; if not, just return to * the guest. */
long int kvmppc_rm_h_confer(struct kvm_vcpu *vcpu, int target, unsigned int yield_count) { struct kvmppc_vcore *vc = local_paca->kvm_hstate.kvm_vcore; int ptid = local_paca->kvm_hstate.ptid; int threads_running; int threads_ceded; int threads_conferring; u64 stop = get_tb() + 10 * tb_ticks_per_usec; int rv = H_SUCCESS; /* => don't yield */ set_bit(ptid, &vc->conferring_threads); while ((get_tb() < stop) && !VCORE_IS_EXITING(vc)) { threads_running = VCORE_ENTRY_MAP(vc); threads_ceded = vc->napping_threads; threads_conferring = vc->conferring_threads; if ((threads_ceded | threads_conferring) == threads_running) { rv = H_TOO_HARD; /* => do yield */ break; } } clear_bit(ptid, &vc->conferring_threads); return rv; }

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sam bobroffsam bobroff12186.43%133.33%
paul mackerraspaul mackerras1913.57%266.67%
Total140100.00%3100.00%

/* * When running HV mode KVM we need to block certain operations while KVM VMs * exist in the system. We use a counter of VMs to track this. * * One of the operations we need to block is onlining of secondaries, so we * protect hv_vm_count with get/put_online_cpus(). */ static atomic_t hv_vm_count;
void kvm_hv_vm_activated(void) { get_online_cpus(); atomic_inc(&hv_vm_count); put_online_cpus(); }

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michael ellermanmichael ellerman19100.00%1100.00%
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EXPORT_SYMBOL_GPL(kvm_hv_vm_activated);
void kvm_hv_vm_deactivated(void) { get_online_cpus(); atomic_dec(&hv_vm_count); put_online_cpus(); }

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michael ellermanmichael ellerman19100.00%1100.00%
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EXPORT_SYMBOL_GPL(kvm_hv_vm_deactivated);
bool kvm_hv_mode_active(void) { return atomic_read(&hv_vm_count) != 0; }

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michael ellermanmichael ellerman16100.00%1100.00%
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extern int hcall_real_table[], hcall_real_table_end[];
int kvmppc_hcall_impl_hv_realmode(unsigned long cmd) { cmd /= 4; if (cmd < hcall_real_table_end - hcall_real_table && hcall_real_table[cmd]) return 1; return 0; }

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paul mackerraspaul mackerras32100.00%1100.00%
Total32100.00%1100.00%

EXPORT_SYMBOL_GPL(kvmppc_hcall_impl_hv_realmode);
int kvmppc_hwrng_present(void) { return powernv_hwrng_present(); }

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michael ellermanmichael ellerman11100.00%1100.00%
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EXPORT_SYMBOL_GPL(kvmppc_hwrng_present);
long kvmppc_h_random(struct kvm_vcpu *vcpu) { if (powernv_get_random_real_mode(&vcpu->arch.gpr[4])) return H_SUCCESS; return H_HARDWARE; }

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michael ellermanmichael ellerman31100.00%1100.00%
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static inline void rm_writeb(unsigned long paddr, u8 val) { __asm__ __volatile__("stbcix %0,0,%1" : : "r" (val), "r" (paddr) : "memory"); }

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paul mackerraspaul mackerras17100.00%1100.00%
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/* * Send an interrupt or message to another CPU. * This can only be called in real mode. * The caller needs to include any barrier needed to order writes * to memory vs. the IPI/message. */
void kvmhv_rm_send_ipi(int cpu) { unsigned long xics_phys; /* On POWER8 for IPIs to threads in the same core, use msgsnd */ if (cpu_has_feature(CPU_FTR_ARCH_207S) && cpu_first_thread_sibling(cpu) == cpu_first_thread_sibling(raw_smp_processor_id())) { unsigned long msg = PPC_DBELL_TYPE(PPC_DBELL_SERVER); msg |= cpu_thread_in_core(cpu); __asm__ __volatile__ (PPC_MSGSND(%0) : : "r" (msg)); return; } /* Else poke the target with an IPI */ xics_phys = paca[cpu].kvm_hstate.xics_phys; rm_writeb(xics_phys + XICS_MFRR, IPI_PRIORITY); }

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paul mackerraspaul mackerras74100.00%2100.00%
Total74100.00%2100.00%

/* * The following functions are called from the assembly code * in book3s_hv_rmhandlers.S. */
static void kvmhv_interrupt_vcore(struct kvmppc_vcore *vc, int active) { int cpu = vc->pcpu; /* Order setting of exit map vs. msgsnd/IPI */ smp_mb(); for (; active; active >>= 1, ++cpu) if (active & 1) kvmhv_rm_send_ipi(cpu); }

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paul mackerraspaul mackerras48100.00%1100.00%
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void kvmhv_commence_exit(int trap) { struct kvmppc_vcore *vc = local_paca->kvm_hstate.kvm_vcore; int ptid = local_paca->kvm_hstate.ptid; struct kvm_split_mode *sip = local_paca->kvm_hstate.kvm_split_mode; int me, ee, i; /* Set our bit in the threads-exiting-guest map in the 0xff00 bits of vcore->entry_exit_map */ me = 0x100 << ptid; do { ee = vc->entry_exit_map; } while (cmpxchg(&vc->entry_exit_map, ee, ee | me) != ee); /* Are we the first here? */ if ((ee >> 8) != 0) return; /* * Trigger the other threads in this vcore to exit the guest. * If this is a hypervisor decrementer interrupt then they * will be already on their way out of the guest. */ if (trap != BOOK3S_INTERRUPT_HV_DECREMENTER) kvmhv_interrupt_vcore(vc, ee & ~(1 << ptid)); /* * If we are doing dynamic micro-threading, interrupt the other * subcores to pull them out of their guests too. */ if (!sip) return; for (i = 0; i < MAX_SUBCORES; ++i) { vc = sip->master_vcs[i]; if (!vc) break; do { ee = vc->entry_exit_map; /* Already asked to exit? */ if ((ee >> 8) != 0) break; } while (cmpxchg(&vc->entry_exit_map, ee, ee | VCORE_EXIT_REQ) != ee); if ((ee >> 8) == 0) kvmhv_interrupt_vcore(vc, ee); } }

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paul mackerraspaul mackerras208100.00%2100.00%
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struct kvmppc_host_rm_ops *kvmppc_host_rm_ops_hv; EXPORT_SYMBOL_GPL(kvmppc_host_rm_ops_hv);

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paul mackerraspaul mackerras44746.23%942.86%
aneesh kumaraneesh kumar14815.31%29.52%
sam bobroffsam bobroff12512.93%14.76%
michael ellermanmichael ellerman12212.62%29.52%
alexander grafalexander graf606.20%14.76%
joonsoo kimjoonsoo kim495.07%29.52%
suresh e. warriersuresh e. warrier101.03%14.76%
paul gortmakerpaul gortmaker30.31%14.76%
alexey kardashevskiyalexey kardashevskiy20.21%14.76%
anton blanchardanton blanchard10.10%14.76%
Total967100.00%21100.00%
Directory: arch/powerpc/kvm
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