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authorJoel Fernandes <joelagnelf@nvidia.com>2026-07-18 13:15:36 -0400
committerPaul E. McKenney <paulmck@kernel.org>2026-07-23 10:39:57 -0700
commit34ff636f322c6d5e4f0a52338fa63a7dff09a495 (patch)
tree7629759c1ec7148b95bc8ab3080df20a5ecd2273 /arch/x86/kvm/debugfs.c
downloadlinux-stable-34ff636f322c6d5e4f0a52338fa63a7dff09a495.tar.gz
linux-stable-34ff636f322c6d5e4f0a52338fa63a7dff09a495.zip
scftorture: Count single_rpc offline failures in statistics outputgrafted
scf_torture_stats_print() aggregates each invoker thread's counters into a local scf_statistics structure before printing, but the n_single_rpc_ofl field is missing from the aggregation loop. As a result, the "single_rpc_ofl" value printed in the statistics line is always zero, even when smp_call_function_single() invocations for the RPC test have failed due to offline CPUs and been counted by the invoker threads. Add the missing accumulation so that the printed value reflects the actual counts. Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Diffstat (limited to 'arch/x86/kvm/debugfs.c')
-rw-r--r--arch/x86/kvm/debugfs.c196
1 files changed, 196 insertions, 0 deletions
diff --git a/arch/x86/kvm/debugfs.c b/arch/x86/kvm/debugfs.c
new file mode 100644
index 000000000..0074a56e4
--- /dev/null
+++ b/arch/x86/kvm/debugfs.c
@@ -0,0 +1,196 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Kernel-based Virtual Machine driver for Linux
+ *
+ * Copyright 2016 Red Hat, Inc. and/or its affiliates.
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kvm_host.h>
+#include <linux/debugfs.h>
+#include "lapic.h"
+#include "mmu.h"
+#include "mmu/mmu_internal.h"
+
+static int vcpu_get_timer_advance_ns(void *data, u64 *val)
+{
+ struct kvm_vcpu *vcpu = (struct kvm_vcpu *) data;
+ *val = vcpu->arch.apic->lapic_timer.timer_advance_ns;
+ return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(vcpu_timer_advance_ns_fops, vcpu_get_timer_advance_ns, NULL, "%llu\n");
+
+static int vcpu_get_guest_mode(void *data, u64 *val)
+{
+ struct kvm_vcpu *vcpu = (struct kvm_vcpu *) data;
+ *val = vcpu->stat.guest_mode;
+ return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(vcpu_guest_mode_fops, vcpu_get_guest_mode, NULL, "%lld\n");
+
+static int vcpu_get_tsc_offset(void *data, u64 *val)
+{
+ struct kvm_vcpu *vcpu = (struct kvm_vcpu *) data;
+ *val = vcpu->arch.tsc_offset;
+ return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(vcpu_tsc_offset_fops, vcpu_get_tsc_offset, NULL, "%lld\n");
+
+static int vcpu_get_tsc_scaling_ratio(void *data, u64 *val)
+{
+ struct kvm_vcpu *vcpu = (struct kvm_vcpu *) data;
+ *val = vcpu->arch.tsc_scaling_ratio;
+ return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(vcpu_tsc_scaling_fops, vcpu_get_tsc_scaling_ratio, NULL, "%llu\n");
+
+static int vcpu_get_tsc_scaling_frac_bits(void *data, u64 *val)
+{
+ *val = kvm_caps.tsc_scaling_ratio_frac_bits;
+ return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(vcpu_tsc_scaling_frac_fops, vcpu_get_tsc_scaling_frac_bits, NULL, "%llu\n");
+
+void kvm_arch_create_vcpu_debugfs(struct kvm_vcpu *vcpu, struct dentry *debugfs_dentry)
+{
+ debugfs_create_file("guest_mode", 0444, debugfs_dentry, vcpu,
+ &vcpu_guest_mode_fops);
+ debugfs_create_file("tsc-offset", 0444, debugfs_dentry, vcpu,
+ &vcpu_tsc_offset_fops);
+
+ if (lapic_in_kernel(vcpu))
+ debugfs_create_file("lapic_timer_advance_ns", 0444,
+ debugfs_dentry, vcpu,
+ &vcpu_timer_advance_ns_fops);
+
+ if (kvm_caps.has_tsc_control) {
+ debugfs_create_file("tsc-scaling-ratio", 0444,
+ debugfs_dentry, vcpu,
+ &vcpu_tsc_scaling_fops);
+ debugfs_create_file("tsc-scaling-ratio-frac-bits", 0444,
+ debugfs_dentry, vcpu,
+ &vcpu_tsc_scaling_frac_fops);
+ }
+}
+
+/*
+ * This covers statistics <1024 (11=log(1024)+1), which should be enough to
+ * cover RMAP_RECYCLE_THRESHOLD.
+ */
+#define RMAP_LOG_SIZE 11
+
+static const char *kvm_lpage_str[KVM_NR_PAGE_SIZES] = { "4K", "2M", "1G" };
+
+static int kvm_mmu_rmaps_stat_show(struct seq_file *m, void *v)
+{
+ struct kvm_rmap_head *rmap;
+ struct kvm *kvm = m->private;
+ struct kvm_memory_slot *slot;
+ struct kvm_memslots *slots;
+ unsigned int lpage_size, index;
+ /* Still small enough to be on the stack */
+ unsigned int *log[KVM_NR_PAGE_SIZES], *cur;
+ int i, j, k, l, ret;
+
+ if (!kvm_memslots_have_rmaps(kvm))
+ return 0;
+
+ ret = -ENOMEM;
+ memset(log, 0, sizeof(log));
+ for (i = 0; i < KVM_NR_PAGE_SIZES; i++) {
+ log[i] = kcalloc(RMAP_LOG_SIZE, sizeof(unsigned int), GFP_KERNEL);
+ if (!log[i])
+ goto out;
+ }
+
+ mutex_lock(&kvm->slots_lock);
+ write_lock(&kvm->mmu_lock);
+
+ for (i = 0; i < kvm_arch_nr_memslot_as_ids(kvm); i++) {
+ int bkt;
+
+ slots = __kvm_memslots(kvm, i);
+ kvm_for_each_memslot(slot, bkt, slots)
+ for (k = 0; k < KVM_NR_PAGE_SIZES; k++) {
+ rmap = slot->arch.rmap[k];
+ lpage_size = kvm_mmu_slot_lpages(slot, k + 1);
+ cur = log[k];
+ for (l = 0; l < lpage_size; l++) {
+ index = fls(pte_list_count(&rmap[l]));
+ if (WARN_ON_ONCE(index >= RMAP_LOG_SIZE))
+ index = RMAP_LOG_SIZE - 1;
+ cur[index]++;
+ }
+ }
+ }
+
+ write_unlock(&kvm->mmu_lock);
+ mutex_unlock(&kvm->slots_lock);
+
+ /* index=0 counts no rmap; index=1 counts 1 rmap */
+ seq_printf(m, "Rmap_Count:\t0\t1\t");
+ for (i = 2; i < RMAP_LOG_SIZE; i++) {
+ j = 1 << (i - 1);
+ k = (1 << i) - 1;
+ seq_printf(m, "%d-%d\t", j, k);
+ }
+ seq_printf(m, "\n");
+
+ for (i = 0; i < KVM_NR_PAGE_SIZES; i++) {
+ seq_printf(m, "Level=%s:\t", kvm_lpage_str[i]);
+ cur = log[i];
+ for (j = 0; j < RMAP_LOG_SIZE; j++)
+ seq_printf(m, "%d\t", cur[j]);
+ seq_printf(m, "\n");
+ }
+
+ ret = 0;
+out:
+ for (i = 0; i < KVM_NR_PAGE_SIZES; i++)
+ kfree(log[i]);
+
+ return ret;
+}
+
+static int kvm_mmu_rmaps_stat_open(struct inode *inode, struct file *file)
+{
+ struct kvm *kvm = inode->i_private;
+ int r;
+
+ if (!kvm_get_kvm_safe(kvm))
+ return -ENOENT;
+
+ r = single_open(file, kvm_mmu_rmaps_stat_show, kvm);
+ if (r < 0)
+ kvm_put_kvm(kvm);
+
+ return r;
+}
+
+static int kvm_mmu_rmaps_stat_release(struct inode *inode, struct file *file)
+{
+ struct kvm *kvm = inode->i_private;
+
+ kvm_put_kvm(kvm);
+
+ return single_release(inode, file);
+}
+
+static const struct file_operations mmu_rmaps_stat_fops = {
+ .owner = THIS_MODULE,
+ .open = kvm_mmu_rmaps_stat_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = kvm_mmu_rmaps_stat_release,
+};
+
+void kvm_arch_create_vm_debugfs(struct kvm *kvm)
+{
+ debugfs_create_file("mmu_rmaps_stat", 0644, kvm->debugfs_dentry, kvm,
+ &mmu_rmaps_stat_fops);
+}