trace_output.c

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/*
 * trace_output.c
 *
 * Copyright (C) 2008 Red Hat Inc, Steven Rostedt <[email protected]>
 *
 */

#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/ftrace.h>

#include "trace_output.h"

/* must be a power of 2 */
#define EVENT_HASHSIZE  128

DECLARE_RWSEM(trace_event_mutex);

static struct hlist_head event_hash[EVENT_HASHSIZE] __read_mostly;

static int next_event_type = __TRACE_LAST_TYPE + 1;

int trace_print_seq(struct seq_file *m, struct trace_seq *s)
{
    int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len;
    int ret;

    ret = seq_write(m, s->buffer, len);

    /*
     * Only reset this buffer if we successfully wrote to the
     * seq_file buffer.
     */
    if (!ret)
        trace_seq_init(s);

    return ret;
}

enum print_line_t trace_print_bprintk_msg_only(struct trace_iterator *iter)
{
    struct trace_seq *s = &iter->seq;
    struct trace_entry *entry = iter->ent;
    struct bprint_entry *field;
    int ret;

    trace_assign_type(field, entry);

    ret = trace_seq_bprintf(s, field->fmt, field->buf);
    if (!ret)
        return TRACE_TYPE_PARTIAL_LINE;

    return TRACE_TYPE_HANDLED;
}

enum print_line_t trace_print_printk_msg_only(struct trace_iterator *iter)
{
    struct trace_seq *s = &iter->seq;
    struct trace_entry *entry = iter->ent;
    struct print_entry *field;
    int ret;

    trace_assign_type(field, entry);

    ret = trace_seq_printf(s, "%s", field->buf);
    if (!ret)
        return TRACE_TYPE_PARTIAL_LINE;

    return TRACE_TYPE_HANDLED;
}

int
trace_seq_printf(struct trace_seq *s, const char *fmt, ...)
{
    int len = (PAGE_SIZE - 1) - s->len;
    va_list ap;
    int ret;

    if (s->full || !len)
        return 0;

    va_start(ap, fmt);
    ret = vsnprintf(s->buffer + s->len, len, fmt, ap);
    va_end(ap);

    /* If we can't write it all, don't bother writing anything */
    if (ret >= len) {
        s->full = 1;
        return 0;
    }

    s->len += ret;

    return 1;
}
EXPORT_SYMBOL_GPL(trace_seq_printf);

int
trace_seq_vprintf(struct trace_seq *s, const char *fmt, va_list args)
{
    int len = (PAGE_SIZE - 1) - s->len;
    int ret;

    if (s->full || !len)
        return 0;

    ret = vsnprintf(s->buffer + s->len, len, fmt, args);

    /* If we can't write it all, don't bother writing anything */
    if (ret >= len) {
        s->full = 1;
        return 0;
    }

    s->len += ret;

    return len;
}
EXPORT_SYMBOL_GPL(trace_seq_vprintf);

int trace_seq_bprintf(struct trace_seq *s, const char *fmt, const u32 *binary)
{
    int len = (PAGE_SIZE - 1) - s->len;
    int ret;

    if (s->full || !len)
        return 0;

    ret = bstr_printf(s->buffer + s->len, len, fmt, binary);

    /* If we can't write it all, don't bother writing anything */
    if (ret >= len) {
        s->full = 1;
        return 0;
    }

    s->len += ret;

    return len;
}

int trace_seq_puts(struct trace_seq *s, const char *str)
{
    int len = strlen(str);

    if (s->full)
        return 0;

    if (len > ((PAGE_SIZE - 1) - s->len)) {
        s->full = 1;
        return 0;
    }

    memcpy(s->buffer + s->len, str, len);
    s->len += len;

    return len;
}

int trace_seq_putc(struct trace_seq *s, unsigned char c)
{
    if (s->full)
        return 0;

    if (s->len >= (PAGE_SIZE - 1)) {
        s->full = 1;
        return 0;
    }

    s->buffer[s->len++] = c;

    return 1;
}
EXPORT_SYMBOL(trace_seq_putc);

int trace_seq_putmem(struct trace_seq *s, const void *mem, size_t len)
{
    if (s->full)
        return 0;

    if (len > ((PAGE_SIZE - 1) - s->len)) {
        s->full = 1;
        return 0;
    }

    memcpy(s->buffer + s->len, mem, len);
    s->len += len;

    return len;
}

int trace_seq_putmem_hex(struct trace_seq *s, const void *mem, size_t len)
{
    unsigned char hex[HEX_CHARS];
    const unsigned char *data = mem;
    int i, j;

    if (s->full)
        return 0;

#ifdef __BIG_ENDIAN
    for (i = 0, j = 0; i < len; i++) {
#else
    for (i = len-1, j = 0; i >= 0; i--) {
#endif
        hex[j++] = hex_asc_hi(data[i]);
        hex[j++] = hex_asc_lo(data[i]);
    }
    hex[j++] = ' ';

    return trace_seq_putmem(s, hex, j);
}

void *trace_seq_reserve(struct trace_seq *s, size_t len)
{
    void *ret;

    if (s->full)
        return NULL;

    if (len > ((PAGE_SIZE - 1) - s->len)) {
        s->full = 1;
        return NULL;
    }

    ret = s->buffer + s->len;
    s->len += len;

    return ret;
}

int trace_seq_path(struct trace_seq *s, const struct path *path)
{
    unsigned char *p;

    if (s->full)
        return 0;

    if (s->len >= (PAGE_SIZE - 1)) {
        s->full = 1;
        return 0;
    }

    p = d_path(path, s->buffer + s->len, PAGE_SIZE - s->len);
    if (!IS_ERR(p)) {
        p = mangle_path(s->buffer + s->len, p, "\n");
        if (p) {
            s->len = p - s->buffer;
            return 1;
        }
    } else {
        s->buffer[s->len++] = '?';
        return 1;
    }

    s->full = 1;
    return 0;
}

const char *
ftrace_print_flags_seq(struct trace_seq *p, const char *delim,
               unsigned long flags,
               const struct trace_print_flags *flag_array)
{
    unsigned long mask;
    const char *str;
    const char *ret = p->buffer + p->len;
    int i, first = 1;

    for (i = 0;  flag_array[i].name && flags; i++) {

        mask = flag_array[i].mask;
        if ((flags & mask) != mask)
            continue;

        str = flag_array[i].name;
        flags &= ~mask;
        if (!first && delim)
            trace_seq_puts(p, delim);
        else
            first = 0;
        trace_seq_puts(p, str);
    }

    /* check for left over flags */
    if (flags) {
        if (!first && delim)
            trace_seq_puts(p, delim);
        trace_seq_printf(p, "0x%lx", flags);
    }

    trace_seq_putc(p, 0);

    return ret;
}
EXPORT_SYMBOL(ftrace_print_flags_seq);

const char *
ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val,
             const struct trace_print_flags *symbol_array)
{
    int i;
    const char *ret = p->buffer + p->len;

    for (i = 0;  symbol_array[i].name; i++) {

        if (val != symbol_array[i].mask)
            continue;

        trace_seq_puts(p, symbol_array[i].name);
        break;
    }

    if (ret == (const char *)(p->buffer + p->len))
        trace_seq_printf(p, "0x%lx", val);
        
    trace_seq_putc(p, 0);

    return ret;
}
EXPORT_SYMBOL(ftrace_print_symbols_seq);

#if BITS_PER_LONG == 32
const char *
ftrace_print_symbols_seq_u64(struct trace_seq *p, unsigned long long val,
             const struct trace_print_flags_u64 *symbol_array)
{
    int i;
    const char *ret = p->buffer + p->len;

    for (i = 0;  symbol_array[i].name; i++) {

        if (val != symbol_array[i].mask)
            continue;

        trace_seq_puts(p, symbol_array[i].name);
        break;
    }

    if (ret == (const char *)(p->buffer + p->len))
        trace_seq_printf(p, "0x%llx", val);

    trace_seq_putc(p, 0);

    return ret;
}
EXPORT_SYMBOL(ftrace_print_symbols_seq_u64);
#endif

const char *
ftrace_print_hex_seq(struct trace_seq *p, const unsigned char *buf, int buf_len)
{
    int i;
    const char *ret = p->buffer + p->len;

    for (i = 0; i < buf_len; i++)
        trace_seq_printf(p, "%s%2.2x", i == 0 ? "" : " ", buf[i]);

    trace_seq_putc(p, 0);

    return ret;
}
EXPORT_SYMBOL(ftrace_print_hex_seq);

#ifdef CONFIG_KRETPROBES
static inline const char *kretprobed(const char *name)
{
    static const char tramp_name[] = "kretprobe_trampoline";
    int size = sizeof(tramp_name);

    if (strncmp(tramp_name, name, size) == 0)
        return "[unknown/kretprobe'd]";
    return name;
}
#else
static inline const char *kretprobed(const char *name)
{
    return name;
}
#endif /* CONFIG_KRETPROBES */

static int
seq_print_sym_short(struct trace_seq *s, const char *fmt, unsigned long address)
{
#ifdef CONFIG_KALLSYMS
    char str[KSYM_SYMBOL_LEN];
    const char *name;

    kallsyms_lookup(address, NULL, NULL, NULL, str);

    name = kretprobed(str);

    return trace_seq_printf(s, fmt, name);
#endif
    return 1;
}

static int
seq_print_sym_offset(struct trace_seq *s, const char *fmt,
             unsigned long address)
{
#ifdef CONFIG_KALLSYMS
    char str[KSYM_SYMBOL_LEN];
    const char *name;

    sprint_symbol(str, address);
    name = kretprobed(str);

    return trace_seq_printf(s, fmt, name);
#endif
    return 1;
}

#ifndef CONFIG_64BIT
# define IP_FMT "%08lx"
#else
# define IP_FMT "%016lx"
#endif

int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm,
              unsigned long ip, unsigned long sym_flags)
{
    struct file *file = NULL;
    unsigned long vmstart = 0;
    int ret = 1;

    if (s->full)
        return 0;

    if (mm) {
        const struct vm_area_struct *vma;

        down_read(&mm->mmap_sem);
        vma = find_vma(mm, ip);
        if (vma) {
            file = vma->vm_file;
            vmstart = vma->vm_start;
        }
        if (file) {
            ret = trace_seq_path(s, &file->f_path);
            if (ret)
                ret = trace_seq_printf(s, "[+0x%lx]",
                               ip - vmstart);
        }
        up_read(&mm->mmap_sem);
    }
    if (ret && ((sym_flags & TRACE_ITER_SYM_ADDR) || !file))
        ret = trace_seq_printf(s, " <" IP_FMT ">", ip);
    return ret;
}

int
seq_print_userip_objs(const struct userstack_entry *entry, struct trace_seq *s,
              unsigned long sym_flags)
{
    struct mm_struct *mm = NULL;
    int ret = 1;
    unsigned int i;

    if (trace_flags & TRACE_ITER_SYM_USEROBJ) {
        struct task_struct *task;
        /*
         * we do the lookup on the thread group leader,
         * since individual threads might have already quit!
         */
        rcu_read_lock();
        task = find_task_by_vpid(entry->tgid);
        if (task)
            mm = get_task_mm(task);
        rcu_read_unlock();
    }

    for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
        unsigned long ip = entry->caller[i];

        if (ip == ULONG_MAX || !ret)
            break;
        if (ret)
            ret = trace_seq_puts(s, " => ");
        if (!ip) {
            if (ret)
                ret = trace_seq_puts(s, "??");
            if (ret)
                ret = trace_seq_puts(s, "\n");
            continue;
        }
        if (!ret)
            break;
        if (ret)
            ret = seq_print_user_ip(s, mm, ip, sym_flags);
        ret = trace_seq_puts(s, "\n");
    }

    if (mm)
        mmput(mm);
    return ret;
}

int
seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags)
{
    int ret;

    if (!ip)
        return trace_seq_printf(s, "0");

    if (sym_flags & TRACE_ITER_SYM_OFFSET)
        ret = seq_print_sym_offset(s, "%s", ip);
    else
        ret = seq_print_sym_short(s, "%s", ip);

    if (!ret)
        return 0;

    if (sym_flags & TRACE_ITER_SYM_ADDR)
        ret = trace_seq_printf(s, " <" IP_FMT ">", ip);
    return ret;
}

int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
{
    char hardsoft_irq;
    char need_resched;
    char irqs_off;
    int hardirq;
    int softirq;
    int ret;

    hardirq = entry->flags & TRACE_FLAG_HARDIRQ;
    softirq = entry->flags & TRACE_FLAG_SOFTIRQ;

    irqs_off =
        (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' :
        (entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ? 'X' :
        '.';
    need_resched =
        (entry->flags & TRACE_FLAG_NEED_RESCHED) ? 'N' : '.';
    hardsoft_irq =
        (hardirq && softirq) ? 'H' :
        hardirq ? 'h' :
        softirq ? 's' :
        '.';

    if (!trace_seq_printf(s, "%c%c%c",
                  irqs_off, need_resched, hardsoft_irq))
        return 0;

    if (entry->preempt_count)
        ret = trace_seq_printf(s, "%x", entry->preempt_count);
    else
        ret = trace_seq_putc(s, '.');

    return ret;
}

static int
lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
{
    char comm[TASK_COMM_LEN];

    trace_find_cmdline(entry->pid, comm);

    if (!trace_seq_printf(s, "%8.8s-%-5d %3d",
                  comm, entry->pid, cpu))
        return 0;

    return trace_print_lat_fmt(s, entry);
}

static unsigned long preempt_mark_thresh = 100;

static int
lat_print_timestamp(struct trace_seq *s, u64 abs_usecs,
            unsigned long rel_usecs)
{
    return trace_seq_printf(s, " %4lldus%c: ", abs_usecs,
                rel_usecs > preempt_mark_thresh ? '!' :
                  rel_usecs > 1 ? '+' : ' ');
}

int trace_print_context(struct trace_iterator *iter)
{
    struct trace_seq *s = &iter->seq;
    struct trace_entry *entry = iter->ent;
    unsigned long long t = ns2usecs(iter->ts);
    unsigned long usec_rem = do_div(t, USEC_PER_SEC);
    unsigned long secs = (unsigned long)t;
    char comm[TASK_COMM_LEN];
    int ret;

    trace_find_cmdline(entry->pid, comm);

    ret = trace_seq_printf(s, "%16s-%-5d [%03d] ",
                   comm, entry->pid, iter->cpu);
    if (!ret)
        return 0;

    if (trace_flags & TRACE_ITER_IRQ_INFO) {
        ret = trace_print_lat_fmt(s, entry);
        if (!ret)
            return 0;
    }

    return trace_seq_printf(s, " %5lu.%06lu: ",
                secs, usec_rem);
}

int trace_print_lat_context(struct trace_iterator *iter)
{
    u64 next_ts;
    int ret;
    /* trace_find_next_entry will reset ent_size */
    int ent_size = iter->ent_size;
    struct trace_seq *s = &iter->seq;
    struct trace_entry *entry = iter->ent,
               *next_entry = trace_find_next_entry(iter, NULL,
                                   &next_ts);
    unsigned long verbose = (trace_flags & TRACE_ITER_VERBOSE);
    unsigned long abs_usecs = ns2usecs(iter->ts - iter->tr->time_start);
    unsigned long rel_usecs;

    /* Restore the original ent_size */
    iter->ent_size = ent_size;

    if (!next_entry)
        next_ts = iter->ts;
    rel_usecs = ns2usecs(next_ts - iter->ts);

    if (verbose) {
        char comm[TASK_COMM_LEN];

        trace_find_cmdline(entry->pid, comm);

        ret = trace_seq_printf(s, "%16s %5d %3d %d %08x %08lx [%08llx]"
                       " %ld.%03ldms (+%ld.%03ldms): ", comm,
                       entry->pid, iter->cpu, entry->flags,
                       entry->preempt_count, iter->idx,
                       ns2usecs(iter->ts),
                       abs_usecs / USEC_PER_MSEC,
                       abs_usecs % USEC_PER_MSEC,
                       rel_usecs / USEC_PER_MSEC,
                       rel_usecs % USEC_PER_MSEC);
    } else {
        ret = lat_print_generic(s, entry, iter->cpu);
        if (ret)
            ret = lat_print_timestamp(s, abs_usecs, rel_usecs);
    }

    return ret;
}

static const char state_to_char[] = TASK_STATE_TO_CHAR_STR;

static int task_state_char(unsigned long state)
{
    int bit = state ? __ffs(state) + 1 : 0;

    return bit < sizeof(state_to_char) - 1 ? state_to_char[bit] : '?';
}

struct trace_event *ftrace_find_event(int type)
{
    struct trace_event *event;
    struct hlist_node *n;
    unsigned key;

    key = type & (EVENT_HASHSIZE - 1);

    hlist_for_each_entry(event, n, &event_hash[key], node) {
        if (event->type == type)
            return event;
    }

    return NULL;
}

static LIST_HEAD(ftrace_event_list);

static int trace_search_list(struct list_head **list)
{
    struct trace_event *e;
    int last = __TRACE_LAST_TYPE;

    if (list_empty(&ftrace_event_list)) {
        *list = &ftrace_event_list;
        return last + 1;
    }

    /*
     * We used up all possible max events,
     * lets see if somebody freed one.
     */
    list_for_each_entry(e, &ftrace_event_list, list) {
        if (e->type != last + 1)
            break;
        last++;
    }

    /* Did we used up all 65 thousand events??? */
    if ((last + 1) > FTRACE_MAX_EVENT)
        return 0;

    *list = &e->list;
    return last + 1;
}

void trace_event_read_lock(void)
{
    down_read(&trace_event_mutex);
}

void trace_event_read_unlock(void)
{
    up_read(&trace_event_mutex);
}

int register_ftrace_event(struct trace_event *event)
{
    unsigned key;
    int ret = 0;

    down_write(&trace_event_mutex);

    if (WARN_ON(!event))
        goto out;

    if (WARN_ON(!event->funcs))
        goto out;

    INIT_LIST_HEAD(&event->list);

    if (!event->type) {
        struct list_head *list = NULL;

        if (next_event_type > FTRACE_MAX_EVENT) {

            event->type = trace_search_list(&list);
            if (!event->type)
                goto out;

        } else {
            
            event->type = next_event_type++;
            list = &ftrace_event_list;
        }

        if (WARN_ON(ftrace_find_event(event->type)))
            goto out;

        list_add_tail(&event->list, list);

    } else if (event->type > __TRACE_LAST_TYPE) {
        printk(KERN_WARNING "Need to add type to trace.h\n");
        WARN_ON(1);
        goto out;
    } else {
        /* Is this event already used */
        if (ftrace_find_event(event->type))
            goto out;
    }

    if (event->funcs->trace == NULL)
        event->funcs->trace = trace_nop_print;
    if (event->funcs->raw == NULL)
        event->funcs->raw = trace_nop_print;
    if (event->funcs->hex == NULL)
        event->funcs->hex = trace_nop_print;
    if (event->funcs->binary == NULL)
        event->funcs->binary = trace_nop_print;

    key = event->type & (EVENT_HASHSIZE - 1);

    hlist_add_head(&event->node, &event_hash[key]);

    ret = event->type;
 out:
    up_write(&trace_event_mutex);

    return ret;
}
EXPORT_SYMBOL_GPL(register_ftrace_event);

/*
 * Used by module code with the trace_event_mutex held for write.
 */
int __unregister_ftrace_event(struct trace_event *event)
{
    hlist_del(&event->node);
    list_del(&event->list);
    return 0;
}

int unregister_ftrace_event(struct trace_event *event)
{
    down_write(&trace_event_mutex);
    __unregister_ftrace_event(event);
    up_write(&trace_event_mutex);

    return 0;
}
EXPORT_SYMBOL_GPL(unregister_ftrace_event);

/*
 * Standard events
 */

enum print_line_t trace_nop_print(struct trace_iterator *iter, int flags,
                  struct trace_event *event)
{
    if (!trace_seq_printf(&iter->seq, "type: %d\n", iter->ent->type))
        return TRACE_TYPE_PARTIAL_LINE;

    return TRACE_TYPE_HANDLED;
}

/* TRACE_FN */
static enum print_line_t trace_fn_trace(struct trace_iterator *iter, int flags,
                    struct trace_event *event)
{
    struct ftrace_entry *field;
    struct trace_seq *s = &iter->seq;

    trace_assign_type(field, iter->ent);

    if (!seq_print_ip_sym(s, field->ip, flags))
        goto partial;

    if ((flags & TRACE_ITER_PRINT_PARENT) && field->parent_ip) {
        if (!trace_seq_printf(s, " <-"))
            goto partial;
        if (!seq_print_ip_sym(s,
                      field->parent_ip,
                      flags))
            goto partial;
    }
    if (!trace_seq_printf(s, "\n"))
        goto partial;

    return TRACE_TYPE_HANDLED;

 partial:
    return TRACE_TYPE_PARTIAL_LINE;
}

static enum print_line_t trace_fn_raw(struct trace_iterator *iter, int flags,
                      struct trace_event *event)
{
    struct ftrace_entry *field;

    trace_assign_type(field, iter->ent);

    if (!trace_seq_printf(&iter->seq, "%lx %lx\n",
                  field->ip,
                  field->parent_ip))
        return TRACE_TYPE_PARTIAL_LINE;

    return TRACE_TYPE_HANDLED;
}

static enum print_line_t trace_fn_hex(struct trace_iterator *iter, int flags,
                      struct trace_event *event)
{
    struct ftrace_entry *field;
    struct trace_seq *s = &iter->seq;

    trace_assign_type(field, iter->ent);

    SEQ_PUT_HEX_FIELD_RET(s, field->ip);
    SEQ_PUT_HEX_FIELD_RET(s, field->parent_ip);

    return TRACE_TYPE_HANDLED;
}

static enum print_line_t trace_fn_bin(struct trace_iterator *iter, int flags,
                      struct trace_event *event)
{
    struct ftrace_entry *field;
    struct trace_seq *s = &iter->seq;

    trace_assign_type(field, iter->ent);

    SEQ_PUT_FIELD_RET(s, field->ip);
    SEQ_PUT_FIELD_RET(s, field->parent_ip);

    return TRACE_TYPE_HANDLED;
}

static struct trace_event_functions trace_fn_funcs = {
    .trace      = trace_fn_trace,
    .raw        = trace_fn_raw,
    .hex        = trace_fn_hex,
    .binary     = trace_fn_bin,
};

static struct trace_event trace_fn_event = {
    .type       = TRACE_FN,
    .funcs      = &trace_fn_funcs,
};

/* TRACE_CTX an TRACE_WAKE */
static enum print_line_t trace_ctxwake_print(struct trace_iterator *iter,
                         char *delim)
{
    struct ctx_switch_entry *field;
    char comm[TASK_COMM_LEN];
    int S, T;


    trace_assign_type(field, iter->ent);

    T = task_state_char(field->next_state);
    S = task_state_char(field->prev_state);
    trace_find_cmdline(field->next_pid, comm);
    if (!trace_seq_printf(&iter->seq,
                  " %5d:%3d:%c %s [%03d] %5d:%3d:%c %s\n",
                  field->prev_pid,
                  field->prev_prio,
                  S, delim,
                  field->next_cpu,
                  field->next_pid,
                  field->next_prio,
                  T, comm))
        return TRACE_TYPE_PARTIAL_LINE;

    return TRACE_TYPE_HANDLED;
}

static enum print_line_t trace_ctx_print(struct trace_iterator *iter, int flags,
                     struct trace_event *event)
{
    return trace_ctxwake_print(iter, "==>");
}

static enum print_line_t trace_wake_print(struct trace_iterator *iter,
                      int flags, struct trace_event *event)
{
    return trace_ctxwake_print(iter, "  +");
}

static int trace_ctxwake_raw(struct trace_iterator *iter, char S)
{
    struct ctx_switch_entry *field;
    int T;

    trace_assign_type(field, iter->ent);

    if (!S)
        S = task_state_char(field->prev_state);
    T = task_state_char(field->next_state);
    if (!trace_seq_printf(&iter->seq, "%d %d %c %d %d %d %c\n",
                  field->prev_pid,
                  field->prev_prio,
                  S,
                  field->next_cpu,
                  field->next_pid,
                  field->next_prio,
                  T))
        return TRACE_TYPE_PARTIAL_LINE;

    return TRACE_TYPE_HANDLED;
}

static enum print_line_t trace_ctx_raw(struct trace_iterator *iter, int flags,
                       struct trace_event *event)
{
    return trace_ctxwake_raw(iter, 0);
}

static enum print_line_t trace_wake_raw(struct trace_iterator *iter, int flags,
                    struct trace_event *event)
{
    return trace_ctxwake_raw(iter, '+');
}


static int trace_ctxwake_hex(struct trace_iterator *iter, char S)
{
    struct ctx_switch_entry *field;
    struct trace_seq *s = &iter->seq;
    int T;

    trace_assign_type(field, iter->ent);

    if (!S)
        S = task_state_char(field->prev_state);
    T = task_state_char(field->next_state);

    SEQ_PUT_HEX_FIELD_RET(s, field->prev_pid);
    SEQ_PUT_HEX_FIELD_RET(s, field->prev_prio);
    SEQ_PUT_HEX_FIELD_RET(s, S);
    SEQ_PUT_HEX_FIELD_RET(s, field->next_cpu);
    SEQ_PUT_HEX_FIELD_RET(s, field->next_pid);
    SEQ_PUT_HEX_FIELD_RET(s, field->next_prio);
    SEQ_PUT_HEX_FIELD_RET(s, T);

    return TRACE_TYPE_HANDLED;
}

static enum print_line_t trace_ctx_hex(struct trace_iterator *iter, int flags,
                       struct trace_event *event)
{
    return trace_ctxwake_hex(iter, 0);
}

static enum print_line_t trace_wake_hex(struct trace_iterator *iter, int flags,
                    struct trace_event *event)
{
    return trace_ctxwake_hex(iter, '+');
}

static enum print_line_t trace_ctxwake_bin(struct trace_iterator *iter,
                       int flags, struct trace_event *event)
{
    struct ctx_switch_entry *field;
    struct trace_seq *s = &iter->seq;

    trace_assign_type(field, iter->ent);

    SEQ_PUT_FIELD_RET(s, field->prev_pid);
    SEQ_PUT_FIELD_RET(s, field->prev_prio);
    SEQ_PUT_FIELD_RET(s, field->prev_state);
    SEQ_PUT_FIELD_RET(s, field->next_pid);
    SEQ_PUT_FIELD_RET(s, field->next_prio);
    SEQ_PUT_FIELD_RET(s, field->next_state);

    return TRACE_TYPE_HANDLED;
}

static struct trace_event_functions trace_ctx_funcs = {
    .trace      = trace_ctx_print,
    .raw        = trace_ctx_raw,
    .hex        = trace_ctx_hex,
    .binary     = trace_ctxwake_bin,
};

static struct trace_event trace_ctx_event = {
    .type       = TRACE_CTX,
    .funcs      = &trace_ctx_funcs,
};

static struct trace_event_functions trace_wake_funcs = {
    .trace      = trace_wake_print,
    .raw        = trace_wake_raw,
    .hex        = trace_wake_hex,
    .binary     = trace_ctxwake_bin,
};

static struct trace_event trace_wake_event = {
    .type       = TRACE_WAKE,
    .funcs      = &trace_wake_funcs,
};

/* TRACE_STACK */

static enum print_line_t trace_stack_print(struct trace_iterator *iter,
                       int flags, struct trace_event *event)
{
    struct stack_entry *field;
    struct trace_seq *s = &iter->seq;
    unsigned long *p;
    unsigned long *end;

    trace_assign_type(field, iter->ent);
    end = (unsigned long *)((long)iter->ent + iter->ent_size);

    if (!trace_seq_puts(s, "<stack trace>\n"))
        goto partial;

    for (p = field->caller; p && *p != ULONG_MAX && p < end; p++) {
        if (!trace_seq_puts(s, " => "))
            goto partial;

        if (!seq_print_ip_sym(s, *p, flags))
            goto partial;
        if (!trace_seq_puts(s, "\n"))
            goto partial;
    }

    return TRACE_TYPE_HANDLED;

 partial:
    return TRACE_TYPE_PARTIAL_LINE;
}

static struct trace_event_functions trace_stack_funcs = {
    .trace      = trace_stack_print,
};

static struct trace_event trace_stack_event = {
    .type       = TRACE_STACK,
    .funcs      = &trace_stack_funcs,
};

/* TRACE_USER_STACK */
static enum print_line_t trace_user_stack_print(struct trace_iterator *iter,
                        int flags, struct trace_event *event)
{
    struct userstack_entry *field;
    struct trace_seq *s = &iter->seq;

    trace_assign_type(field, iter->ent);

    if (!trace_seq_puts(s, "<user stack trace>\n"))
        goto partial;

    if (!seq_print_userip_objs(field, s, flags))
        goto partial;

    return TRACE_TYPE_HANDLED;

 partial:
    return TRACE_TYPE_PARTIAL_LINE;
}

static struct trace_event_functions trace_user_stack_funcs = {
    .trace      = trace_user_stack_print,
};

static struct trace_event trace_user_stack_event = {
    .type       = TRACE_USER_STACK,
    .funcs      = &trace_user_stack_funcs,
};

/* TRACE_BPRINT */
static enum print_line_t
trace_bprint_print(struct trace_iterator *iter, int flags,
           struct trace_event *event)
{
    struct trace_entry *entry = iter->ent;
    struct trace_seq *s = &iter->seq;
    struct bprint_entry *field;

    trace_assign_type(field, entry);

    if (!seq_print_ip_sym(s, field->ip, flags))
        goto partial;

    if (!trace_seq_puts(s, ": "))
        goto partial;

    if (!trace_seq_bprintf(s, field->fmt, field->buf))
        goto partial;

    return TRACE_TYPE_HANDLED;

 partial:
    return TRACE_TYPE_PARTIAL_LINE;
}


static enum print_line_t
trace_bprint_raw(struct trace_iterator *iter, int flags,
         struct trace_event *event)
{
    struct bprint_entry *field;
    struct trace_seq *s = &iter->seq;

    trace_assign_type(field, iter->ent);

    if (!trace_seq_printf(s, ": %lx : ", field->ip))
        goto partial;

    if (!trace_seq_bprintf(s, field->fmt, field->buf))
        goto partial;

    return TRACE_TYPE_HANDLED;

 partial:
    return TRACE_TYPE_PARTIAL_LINE;
}

static struct trace_event_functions trace_bprint_funcs = {
    .trace      = trace_bprint_print,
    .raw        = trace_bprint_raw,
};

static struct trace_event trace_bprint_event = {
    .type       = TRACE_BPRINT,
    .funcs      = &trace_bprint_funcs,
};

/* TRACE_PRINT */
static enum print_line_t trace_print_print(struct trace_iterator *iter,
                       int flags, struct trace_event *event)
{
    struct print_entry *field;
    struct trace_seq *s = &iter->seq;

    trace_assign_type(field, iter->ent);

    if (!seq_print_ip_sym(s, field->ip, flags))
        goto partial;

    if (!trace_seq_printf(s, ": %s", field->buf))
        goto partial;

    return TRACE_TYPE_HANDLED;

 partial:
    return TRACE_TYPE_PARTIAL_LINE;
}

static enum print_line_t trace_print_raw(struct trace_iterator *iter, int flags,
                     struct trace_event *event)
{
    struct print_entry *field;

    trace_assign_type(field, iter->ent);

    if (!trace_seq_printf(&iter->seq, "# %lx %s", field->ip, field->buf))
        goto partial;

    return TRACE_TYPE_HANDLED;

 partial:
    return TRACE_TYPE_PARTIAL_LINE;
}

static struct trace_event_functions trace_print_funcs = {
    .trace      = trace_print_print,
    .raw        = trace_print_raw,
};

static struct trace_event trace_print_event = {
    .type       = TRACE_PRINT,
    .funcs      = &trace_print_funcs,
};


static struct trace_event *events[] __initdata = {
    &trace_fn_event,
    &trace_ctx_event,
    &trace_wake_event,
    &trace_stack_event,
    &trace_user_stack_event,
    &trace_bprint_event,
    &trace_print_event,
    NULL
};

__init static int init_events(void)
{
    struct trace_event *event;
    int i, ret;

    for (i = 0; events[i]; i++) {
        event = events[i];

        ret = register_ftrace_event(event);
        if (!ret) {
            printk(KERN_WARNING "event %d failed to register\n",
                   event->type);
            WARN_ON_ONCE(1);
        }
    }

    return 0;
}
early_initcall(init_events);