| /* |
| * Memory mapped I/O tracing |
| * |
| * Copyright (C) 2008 Pekka Paalanen <pq@iki.fi> |
| */ |
| |
| #define DEBUG 1 |
| |
| #include <linux/kernel.h> |
| #include <linux/mmiotrace.h> |
| #include <linux/pci.h> |
| #include <asm/atomic.h> |
| |
| #include "trace.h" |
| #include "trace_output.h" |
| |
| struct header_iter { |
| struct pci_dev *dev; |
| }; |
| |
| static struct trace_array *mmio_trace_array; |
| static bool overrun_detected; |
| static unsigned long prev_overruns; |
| static atomic_t dropped_count; |
| |
| static void mmio_reset_data(struct trace_array *tr) |
| { |
| overrun_detected = false; |
| prev_overruns = 0; |
| |
| tracing_reset_online_cpus(tr); |
| } |
| |
| static int mmio_trace_init(struct trace_array *tr) |
| { |
| pr_debug("in %s\n", __func__); |
| mmio_trace_array = tr; |
| |
| mmio_reset_data(tr); |
| enable_mmiotrace(); |
| return 0; |
| } |
| |
| static void mmio_trace_reset(struct trace_array *tr) |
| { |
| pr_debug("in %s\n", __func__); |
| |
| disable_mmiotrace(); |
| mmio_reset_data(tr); |
| mmio_trace_array = NULL; |
| } |
| |
| static void mmio_trace_start(struct trace_array *tr) |
| { |
| pr_debug("in %s\n", __func__); |
| mmio_reset_data(tr); |
| } |
| |
| static int mmio_print_pcidev(struct trace_seq *s, const struct pci_dev *dev) |
| { |
| int ret = 0; |
| int i; |
| resource_size_t start, end; |
| const struct pci_driver *drv = pci_dev_driver(dev); |
| |
| /* XXX: incomplete checks for trace_seq_printf() return value */ |
| ret += trace_seq_printf(s, "PCIDEV %02x%02x %04x%04x %x", |
| dev->bus->number, dev->devfn, |
| dev->vendor, dev->device, dev->irq); |
| /* |
| * XXX: is pci_resource_to_user() appropriate, since we are |
| * supposed to interpret the __ioremap() phys_addr argument based on |
| * these printed values? |
| */ |
| for (i = 0; i < 7; i++) { |
| pci_resource_to_user(dev, i, &dev->resource[i], &start, &end); |
| ret += trace_seq_printf(s, " %llx", |
| (unsigned long long)(start | |
| (dev->resource[i].flags & PCI_REGION_FLAG_MASK))); |
| } |
| for (i = 0; i < 7; i++) { |
| pci_resource_to_user(dev, i, &dev->resource[i], &start, &end); |
| ret += trace_seq_printf(s, " %llx", |
| dev->resource[i].start < dev->resource[i].end ? |
| (unsigned long long)(end - start) + 1 : 0); |
| } |
| if (drv) |
| ret += trace_seq_printf(s, " %s\n", drv->name); |
| else |
| ret += trace_seq_printf(s, " \n"); |
| return ret; |
| } |
| |
| static void destroy_header_iter(struct header_iter *hiter) |
| { |
| if (!hiter) |
| return; |
| pci_dev_put(hiter->dev); |
| kfree(hiter); |
| } |
| |
| static void mmio_pipe_open(struct trace_iterator *iter) |
| { |
| struct header_iter *hiter; |
| struct trace_seq *s = &iter->seq; |
| |
| trace_seq_printf(s, "VERSION 20070824\n"); |
| |
| hiter = kzalloc(sizeof(*hiter), GFP_KERNEL); |
| if (!hiter) |
| return; |
| |
| hiter->dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, NULL); |
| iter->private = hiter; |
| } |
| |
| /* XXX: This is not called when the pipe is closed! */ |
| static void mmio_close(struct trace_iterator *iter) |
| { |
| struct header_iter *hiter = iter->private; |
| destroy_header_iter(hiter); |
| iter->private = NULL; |
| } |
| |
| static unsigned long count_overruns(struct trace_iterator *iter) |
| { |
| unsigned long cnt = atomic_xchg(&dropped_count, 0); |
| unsigned long over = ring_buffer_overruns(iter->tr->buffer); |
| |
| if (over > prev_overruns) |
| cnt += over - prev_overruns; |
| prev_overruns = over; |
| return cnt; |
| } |
| |
| static ssize_t mmio_read(struct trace_iterator *iter, struct file *filp, |
| char __user *ubuf, size_t cnt, loff_t *ppos) |
| { |
| ssize_t ret; |
| struct header_iter *hiter = iter->private; |
| struct trace_seq *s = &iter->seq; |
| unsigned long n; |
| |
| n = count_overruns(iter); |
| if (n) { |
| /* XXX: This is later than where events were lost. */ |
| trace_seq_printf(s, "MARK 0.000000 Lost %lu events.\n", n); |
| if (!overrun_detected) |
| pr_warning("mmiotrace has lost events.\n"); |
| overrun_detected = true; |
| goto print_out; |
| } |
| |
| if (!hiter) |
| return 0; |
| |
| mmio_print_pcidev(s, hiter->dev); |
| hiter->dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, hiter->dev); |
| |
| if (!hiter->dev) { |
| destroy_header_iter(hiter); |
| iter->private = NULL; |
| } |
| |
| print_out: |
| ret = trace_seq_to_user(s, ubuf, cnt); |
| return (ret == -EBUSY) ? 0 : ret; |
| } |
| |
| static enum print_line_t mmio_print_rw(struct trace_iterator *iter) |
| { |
| struct trace_entry *entry = iter->ent; |
| struct trace_mmiotrace_rw *field; |
| struct mmiotrace_rw *rw; |
| struct trace_seq *s = &iter->seq; |
| unsigned long long t = ns2usecs(iter->ts); |
| unsigned long usec_rem = do_div(t, 1000000ULL); |
| unsigned secs = (unsigned long)t; |
| int ret = 1; |
| |
| trace_assign_type(field, entry); |
| rw = &field->rw; |
| |
| switch (rw->opcode) { |
| case MMIO_READ: |
| ret = trace_seq_printf(s, |
| "R %d %u.%06lu %d 0x%llx 0x%lx 0x%lx %d\n", |
| rw->width, secs, usec_rem, rw->map_id, |
| (unsigned long long)rw->phys, |
| rw->value, rw->pc, 0); |
| break; |
| case MMIO_WRITE: |
| ret = trace_seq_printf(s, |
| "W %d %u.%06lu %d 0x%llx 0x%lx 0x%lx %d\n", |
| rw->width, secs, usec_rem, rw->map_id, |
| (unsigned long long)rw->phys, |
| rw->value, rw->pc, 0); |
| break; |
| case MMIO_UNKNOWN_OP: |
| ret = trace_seq_printf(s, |
| "UNKNOWN %u.%06lu %d 0x%llx %02lx,%02lx," |
| "%02lx 0x%lx %d\n", |
| secs, usec_rem, rw->map_id, |
| (unsigned long long)rw->phys, |
| (rw->value >> 16) & 0xff, (rw->value >> 8) & 0xff, |
| (rw->value >> 0) & 0xff, rw->pc, 0); |
| break; |
| default: |
| ret = trace_seq_printf(s, "rw what?\n"); |
| break; |
| } |
| if (ret) |
| return TRACE_TYPE_HANDLED; |
| return TRACE_TYPE_PARTIAL_LINE; |
| } |
| |
| static enum print_line_t mmio_print_map(struct trace_iterator *iter) |
| { |
| struct trace_entry *entry = iter->ent; |
| struct trace_mmiotrace_map *field; |
| struct mmiotrace_map *m; |
| struct trace_seq *s = &iter->seq; |
| unsigned long long t = ns2usecs(iter->ts); |
| unsigned long usec_rem = do_div(t, 1000000ULL); |
| unsigned secs = (unsigned long)t; |
| int ret; |
| |
| trace_assign_type(field, entry); |
| m = &field->map; |
| |
| switch (m->opcode) { |
| case MMIO_PROBE: |
| ret = trace_seq_printf(s, |
| "MAP %u.%06lu %d 0x%llx 0x%lx 0x%lx 0x%lx %d\n", |
| secs, usec_rem, m->map_id, |
| (unsigned long long)m->phys, m->virt, m->len, |
| 0UL, 0); |
| break; |
| case MMIO_UNPROBE: |
| ret = trace_seq_printf(s, |
| "UNMAP %u.%06lu %d 0x%lx %d\n", |
| secs, usec_rem, m->map_id, 0UL, 0); |
| break; |
| default: |
| ret = trace_seq_printf(s, "map what?\n"); |
| break; |
| } |
| if (ret) |
| return TRACE_TYPE_HANDLED; |
| return TRACE_TYPE_PARTIAL_LINE; |
| } |
| |
| static enum print_line_t mmio_print_mark(struct trace_iterator *iter) |
| { |
| struct trace_entry *entry = iter->ent; |
| struct print_entry *print = (struct print_entry *)entry; |
| const char *msg = print->buf; |
| struct trace_seq *s = &iter->seq; |
| unsigned long long t = ns2usecs(iter->ts); |
| unsigned long usec_rem = do_div(t, USEC_PER_SEC); |
| unsigned secs = (unsigned long)t; |
| int ret; |
| |
| /* The trailing newline must be in the message. */ |
| ret = trace_seq_printf(s, "MARK %u.%06lu %s", secs, usec_rem, msg); |
| if (!ret) |
| return TRACE_TYPE_PARTIAL_LINE; |
| |
| return TRACE_TYPE_HANDLED; |
| } |
| |
| static enum print_line_t mmio_print_line(struct trace_iterator *iter) |
| { |
| switch (iter->ent->type) { |
| case TRACE_MMIO_RW: |
| return mmio_print_rw(iter); |
| case TRACE_MMIO_MAP: |
| return mmio_print_map(iter); |
| case TRACE_PRINT: |
| return mmio_print_mark(iter); |
| default: |
| return TRACE_TYPE_HANDLED; /* ignore unknown entries */ |
| } |
| } |
| |
| static struct tracer mmio_tracer __read_mostly = |
| { |
| .name = "mmiotrace", |
| .init = mmio_trace_init, |
| .reset = mmio_trace_reset, |
| .start = mmio_trace_start, |
| .pipe_open = mmio_pipe_open, |
| .close = mmio_close, |
| .read = mmio_read, |
| .print_line = mmio_print_line, |
| }; |
| |
| __init static int init_mmio_trace(void) |
| { |
| return register_tracer(&mmio_tracer); |
| } |
| device_initcall(init_mmio_trace); |
| |
| static void __trace_mmiotrace_rw(struct trace_array *tr, |
| struct trace_array_cpu *data, |
| struct mmiotrace_rw *rw) |
| { |
| struct ring_buffer_event *event; |
| struct trace_mmiotrace_rw *entry; |
| int pc = preempt_count(); |
| |
| event = trace_buffer_lock_reserve(tr, TRACE_MMIO_RW, |
| sizeof(*entry), 0, pc); |
| if (!event) { |
| atomic_inc(&dropped_count); |
| return; |
| } |
| entry = ring_buffer_event_data(event); |
| entry->rw = *rw; |
| trace_buffer_unlock_commit(tr, event, 0, pc); |
| } |
| |
| void mmio_trace_rw(struct mmiotrace_rw *rw) |
| { |
| struct trace_array *tr = mmio_trace_array; |
| struct trace_array_cpu *data = tr->data[smp_processor_id()]; |
| __trace_mmiotrace_rw(tr, data, rw); |
| } |
| |
| static void __trace_mmiotrace_map(struct trace_array *tr, |
| struct trace_array_cpu *data, |
| struct mmiotrace_map *map) |
| { |
| struct ring_buffer_event *event; |
| struct trace_mmiotrace_map *entry; |
| int pc = preempt_count(); |
| |
| event = trace_buffer_lock_reserve(tr, TRACE_MMIO_MAP, |
| sizeof(*entry), 0, pc); |
| if (!event) { |
| atomic_inc(&dropped_count); |
| return; |
| } |
| entry = ring_buffer_event_data(event); |
| entry->map = *map; |
| trace_buffer_unlock_commit(tr, event, 0, pc); |
| } |
| |
| void mmio_trace_mapping(struct mmiotrace_map *map) |
| { |
| struct trace_array *tr = mmio_trace_array; |
| struct trace_array_cpu *data; |
| |
| preempt_disable(); |
| data = tr->data[smp_processor_id()]; |
| __trace_mmiotrace_map(tr, data, map); |
| preempt_enable(); |
| } |
| |
| int mmio_trace_printk(const char *fmt, va_list args) |
| { |
| return trace_vprintk(0, -1, fmt, args); |
| } |