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@@ -1,285 +0,0 @@
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-/*
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- * kvm trace
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- *
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- * It is designed to allow debugging traces of kvm to be generated
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- * on UP / SMP machines. Each trace entry can be timestamped so that
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- * it's possible to reconstruct a chronological record of trace events.
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- * The implementation refers to blktrace kernel support.
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- *
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- * Copyright (c) 2008 Intel Corporation
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- * Copyright (C) 2006 Jens Axboe <axboe@kernel.dk>
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- *
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- * Authors: Feng(Eric) Liu, eric.e.liu@intel.com
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- *
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- * Date: Feb 2008
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- */
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-
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-#include <linux/module.h>
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-#include <linux/relay.h>
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-#include <linux/debugfs.h>
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-#include <linux/ktime.h>
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-
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-#include <linux/kvm_host.h>
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-
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-#define KVM_TRACE_STATE_RUNNING (1 << 0)
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-#define KVM_TRACE_STATE_PAUSE (1 << 1)
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-#define KVM_TRACE_STATE_CLEARUP (1 << 2)
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-
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-struct kvm_trace {
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- int trace_state;
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- struct rchan *rchan;
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- struct dentry *lost_file;
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- atomic_t lost_records;
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-};
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-static struct kvm_trace *kvm_trace;
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-
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-struct kvm_trace_probe {
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- const char *name;
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- const char *format;
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- u32 timestamp_in;
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- marker_probe_func *probe_func;
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-};
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-
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-static inline int calc_rec_size(int timestamp, int extra)
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-{
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- int rec_size = KVM_TRC_HEAD_SIZE;
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-
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- rec_size += extra;
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- return timestamp ? rec_size += KVM_TRC_CYCLE_SIZE : rec_size;
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-}
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-
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-static void kvm_add_trace(void *probe_private, void *call_data,
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- const char *format, va_list *args)
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-{
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- struct kvm_trace_probe *p = probe_private;
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- struct kvm_trace *kt = kvm_trace;
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- struct kvm_trace_rec rec;
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- struct kvm_vcpu *vcpu;
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- int i, size;
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- u32 extra;
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-
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- if (unlikely(kt->trace_state != KVM_TRACE_STATE_RUNNING))
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- return;
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-
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- rec.rec_val = TRACE_REC_EVENT_ID(va_arg(*args, u32));
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- vcpu = va_arg(*args, struct kvm_vcpu *);
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- rec.pid = current->tgid;
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- rec.vcpu_id = vcpu->vcpu_id;
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-
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- extra = va_arg(*args, u32);
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- WARN_ON(!(extra <= KVM_TRC_EXTRA_MAX));
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- extra = min_t(u32, extra, KVM_TRC_EXTRA_MAX);
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-
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- rec.rec_val |= TRACE_REC_TCS(p->timestamp_in)
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- | TRACE_REC_NUM_DATA_ARGS(extra);
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-
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- if (p->timestamp_in) {
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- rec.u.timestamp.timestamp = ktime_to_ns(ktime_get());
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-
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- for (i = 0; i < extra; i++)
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- rec.u.timestamp.extra_u32[i] = va_arg(*args, u32);
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- } else {
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- for (i = 0; i < extra; i++)
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- rec.u.notimestamp.extra_u32[i] = va_arg(*args, u32);
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- }
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-
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- size = calc_rec_size(p->timestamp_in, extra * sizeof(u32));
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- relay_write(kt->rchan, &rec, size);
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-}
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-
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-static struct kvm_trace_probe kvm_trace_probes[] = {
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- { "kvm_trace_entryexit", "%u %p %u %u %u %u %u %u", 1, kvm_add_trace },
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- { "kvm_trace_handler", "%u %p %u %u %u %u %u %u", 0, kvm_add_trace },
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-};
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-
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-static int lost_records_get(void *data, u64 *val)
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-{
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- struct kvm_trace *kt = data;
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-
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- *val = atomic_read(&kt->lost_records);
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- return 0;
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-}
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-
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-DEFINE_SIMPLE_ATTRIBUTE(kvm_trace_lost_ops, lost_records_get, NULL, "%llu\n");
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-
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-/*
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- * The relay channel is used in "no-overwrite" mode, it keeps trace of how
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- * many times we encountered a full subbuffer, to tell user space app the
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- * lost records there were.
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- */
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-static int kvm_subbuf_start_callback(struct rchan_buf *buf, void *subbuf,
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- void *prev_subbuf, size_t prev_padding)
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-{
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- struct kvm_trace *kt;
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-
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- if (!relay_buf_full(buf)) {
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- if (!prev_subbuf) {
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- /*
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- * executed only once when the channel is opened
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- * save metadata as first record
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- */
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- subbuf_start_reserve(buf, sizeof(u32));
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- *(u32 *)subbuf = 0x12345678;
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- }
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-
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- return 1;
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- }
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-
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- kt = buf->chan->private_data;
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- atomic_inc(&kt->lost_records);
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-
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- return 0;
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-}
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-
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-static struct dentry *kvm_create_buf_file_callack(const char *filename,
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- struct dentry *parent,
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- int mode,
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- struct rchan_buf *buf,
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- int *is_global)
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-{
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- return debugfs_create_file(filename, mode, parent, buf,
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- &relay_file_operations);
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-}
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-
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-static int kvm_remove_buf_file_callback(struct dentry *dentry)
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-{
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- debugfs_remove(dentry);
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- return 0;
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-}
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-
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-static struct rchan_callbacks kvm_relay_callbacks = {
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- .subbuf_start = kvm_subbuf_start_callback,
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- .create_buf_file = kvm_create_buf_file_callack,
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- .remove_buf_file = kvm_remove_buf_file_callback,
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-};
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-
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-static int do_kvm_trace_enable(struct kvm_user_trace_setup *kuts)
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-{
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- struct kvm_trace *kt;
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- int i, r = -ENOMEM;
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-
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- if (!kuts->buf_size || !kuts->buf_nr)
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- return -EINVAL;
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-
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- kt = kzalloc(sizeof(*kt), GFP_KERNEL);
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- if (!kt)
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- goto err;
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-
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- r = -EIO;
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- atomic_set(&kt->lost_records, 0);
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- kt->lost_file = debugfs_create_file("lost_records", 0444, kvm_debugfs_dir,
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- kt, &kvm_trace_lost_ops);
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- if (!kt->lost_file)
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- goto err;
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-
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- kt->rchan = relay_open("trace", kvm_debugfs_dir, kuts->buf_size,
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- kuts->buf_nr, &kvm_relay_callbacks, kt);
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- if (!kt->rchan)
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- goto err;
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-
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- kvm_trace = kt;
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-
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- for (i = 0; i < ARRAY_SIZE(kvm_trace_probes); i++) {
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- struct kvm_trace_probe *p = &kvm_trace_probes[i];
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-
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- r = marker_probe_register(p->name, p->format, p->probe_func, p);
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- if (r)
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- printk(KERN_INFO "Unable to register probe %s\n",
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- p->name);
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- }
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-
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- kvm_trace->trace_state = KVM_TRACE_STATE_RUNNING;
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-
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- return 0;
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-err:
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- if (kt) {
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- if (kt->lost_file)
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- debugfs_remove(kt->lost_file);
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- if (kt->rchan)
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- relay_close(kt->rchan);
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- kfree(kt);
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- }
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- return r;
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-}
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-
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-static int kvm_trace_enable(char __user *arg)
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-{
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- struct kvm_user_trace_setup kuts;
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- int ret;
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-
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- ret = copy_from_user(&kuts, arg, sizeof(kuts));
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- if (ret)
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- return -EFAULT;
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-
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- ret = do_kvm_trace_enable(&kuts);
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- if (ret)
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- return ret;
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-
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- return 0;
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-}
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-
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-static int kvm_trace_pause(void)
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-{
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- struct kvm_trace *kt = kvm_trace;
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- int r = -EINVAL;
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-
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- if (kt == NULL)
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- return r;
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-
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- if (kt->trace_state == KVM_TRACE_STATE_RUNNING) {
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- kt->trace_state = KVM_TRACE_STATE_PAUSE;
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- relay_flush(kt->rchan);
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- r = 0;
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- }
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-
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- return r;
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-}
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-
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-void kvm_trace_cleanup(void)
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-{
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- struct kvm_trace *kt = kvm_trace;
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- int i;
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-
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- if (kt == NULL)
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- return;
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-
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- if (kt->trace_state == KVM_TRACE_STATE_RUNNING ||
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- kt->trace_state == KVM_TRACE_STATE_PAUSE) {
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-
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- kt->trace_state = KVM_TRACE_STATE_CLEARUP;
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-
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- for (i = 0; i < ARRAY_SIZE(kvm_trace_probes); i++) {
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- struct kvm_trace_probe *p = &kvm_trace_probes[i];
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- marker_probe_unregister(p->name, p->probe_func, p);
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- }
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- marker_synchronize_unregister();
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-
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- relay_close(kt->rchan);
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- debugfs_remove(kt->lost_file);
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- kfree(kt);
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- }
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-}
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-
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-int kvm_trace_ioctl(unsigned int ioctl, unsigned long arg)
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-{
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- void __user *argp = (void __user *)arg;
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- long r = -EINVAL;
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-
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- if (!capable(CAP_SYS_ADMIN))
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- return -EPERM;
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-
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- switch (ioctl) {
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- case KVM_TRACE_ENABLE:
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- r = kvm_trace_enable(argp);
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- break;
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- case KVM_TRACE_PAUSE:
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- r = kvm_trace_pause();
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- break;
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- case KVM_TRACE_DISABLE:
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- r = 0;
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- kvm_trace_cleanup();
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- break;
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- }
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-
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- return r;
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-}
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Marcelo Tosatti