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Currently, function graph tracer prints "!" or "+" just before function execution time to signal a function overhead, depending on the time. And some tracers tracing latency also print "!" or "+" just after time to signal overhead, depending on the interval between events. Even it is usually enough to do that, we sometimes need to signal for bigger execution time than 100 micro seconds. For example, I used function graph tracer to detect if there is any case that exit_mm() takes too much time. I did following steps in /sys/kernel/debug/tracing. It was easier to detect very large excution time with patched kernel than with original kernel. $ echo exit_mm > set_graph_function $ echo function_graph > current_tracer $ echo > trace $ cat trace_pipe > $LOGFILE ... (do something and terminate logging) $ grep "\\$" $LOGFILE 3) $ 22082032 us | } /* kernel_map_pages */ 3) $ 22082040 us | } /* free_pages_prepare */ 3) $ 22082113 us | } /* free_hot_cold_page */ 3) $ 22083455 us | } /* free_hot_cold_page_list */ 3) $ 22083895 us | } /* release_pages */ 3) $ 22177873 us | } /* free_pages_and_swap_cache */ 3) $ 22178929 us | } /* unmap_single_vma */ 3) $ 22198885 us | } /* unmap_vmas */ 3) $ 22206949 us | } /* exit_mmap */ 3) $ 22207659 us | } /* mmput */ 3) $ 22207793 us | } /* exit_mm */ And then, it was easy to find out that a schedule-out occured by sub_preempt_count() within kernel_map_pages(). To detect very large function exection time caused by either problematic function implementation or scheduling issues, this patch can be useful. Link: http://lkml.kernel.org/r/1416789259-24038-1-git-send-email-byungchul.park@lge.com Signed-off-by: Byungchul Park <byungchul.park@lge.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
1212 lines
26 KiB
C
1212 lines
26 KiB
C
/*
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* trace_output.c
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*
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* Copyright (C) 2008 Red Hat Inc, Steven Rostedt <srostedt@redhat.com>
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*
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*/
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#include <linux/module.h>
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#include <linux/mutex.h>
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#include <linux/ftrace.h>
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#include "trace_output.h"
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/* must be a power of 2 */
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#define EVENT_HASHSIZE 128
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DECLARE_RWSEM(trace_event_sem);
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static struct hlist_head event_hash[EVENT_HASHSIZE] __read_mostly;
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static int next_event_type = __TRACE_LAST_TYPE + 1;
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enum print_line_t trace_print_bputs_msg_only(struct trace_iterator *iter)
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{
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struct trace_seq *s = &iter->seq;
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struct trace_entry *entry = iter->ent;
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struct bputs_entry *field;
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trace_assign_type(field, entry);
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trace_seq_puts(s, field->str);
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return trace_handle_return(s);
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}
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enum print_line_t trace_print_bprintk_msg_only(struct trace_iterator *iter)
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{
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struct trace_seq *s = &iter->seq;
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struct trace_entry *entry = iter->ent;
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struct bprint_entry *field;
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trace_assign_type(field, entry);
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trace_seq_bprintf(s, field->fmt, field->buf);
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return trace_handle_return(s);
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}
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enum print_line_t trace_print_printk_msg_only(struct trace_iterator *iter)
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{
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struct trace_seq *s = &iter->seq;
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struct trace_entry *entry = iter->ent;
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struct print_entry *field;
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trace_assign_type(field, entry);
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trace_seq_puts(s, field->buf);
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return trace_handle_return(s);
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}
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const char *
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ftrace_print_flags_seq(struct trace_seq *p, const char *delim,
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unsigned long flags,
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const struct trace_print_flags *flag_array)
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{
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unsigned long mask;
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const char *str;
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const char *ret = trace_seq_buffer_ptr(p);
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int i, first = 1;
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for (i = 0; flag_array[i].name && flags; i++) {
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mask = flag_array[i].mask;
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if ((flags & mask) != mask)
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continue;
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str = flag_array[i].name;
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flags &= ~mask;
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if (!first && delim)
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trace_seq_puts(p, delim);
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else
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first = 0;
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trace_seq_puts(p, str);
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}
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/* check for left over flags */
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if (flags) {
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if (!first && delim)
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trace_seq_puts(p, delim);
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trace_seq_printf(p, "0x%lx", flags);
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}
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trace_seq_putc(p, 0);
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return ret;
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}
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EXPORT_SYMBOL(ftrace_print_flags_seq);
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const char *
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ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val,
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const struct trace_print_flags *symbol_array)
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{
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int i;
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const char *ret = trace_seq_buffer_ptr(p);
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for (i = 0; symbol_array[i].name; i++) {
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if (val != symbol_array[i].mask)
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continue;
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trace_seq_puts(p, symbol_array[i].name);
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break;
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}
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if (ret == (const char *)(trace_seq_buffer_ptr(p)))
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trace_seq_printf(p, "0x%lx", val);
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trace_seq_putc(p, 0);
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return ret;
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}
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EXPORT_SYMBOL(ftrace_print_symbols_seq);
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#if BITS_PER_LONG == 32
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const char *
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ftrace_print_symbols_seq_u64(struct trace_seq *p, unsigned long long val,
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const struct trace_print_flags_u64 *symbol_array)
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{
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int i;
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const char *ret = trace_seq_buffer_ptr(p);
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for (i = 0; symbol_array[i].name; i++) {
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if (val != symbol_array[i].mask)
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continue;
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trace_seq_puts(p, symbol_array[i].name);
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break;
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}
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if (ret == (const char *)(trace_seq_buffer_ptr(p)))
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trace_seq_printf(p, "0x%llx", val);
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trace_seq_putc(p, 0);
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return ret;
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}
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EXPORT_SYMBOL(ftrace_print_symbols_seq_u64);
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#endif
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const char *
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ftrace_print_bitmask_seq(struct trace_seq *p, void *bitmask_ptr,
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unsigned int bitmask_size)
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{
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const char *ret = trace_seq_buffer_ptr(p);
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trace_seq_bitmask(p, bitmask_ptr, bitmask_size * 8);
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trace_seq_putc(p, 0);
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return ret;
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}
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EXPORT_SYMBOL_GPL(ftrace_print_bitmask_seq);
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const char *
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ftrace_print_hex_seq(struct trace_seq *p, const unsigned char *buf, int buf_len)
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{
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int i;
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const char *ret = trace_seq_buffer_ptr(p);
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for (i = 0; i < buf_len; i++)
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trace_seq_printf(p, "%s%2.2x", i == 0 ? "" : " ", buf[i]);
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trace_seq_putc(p, 0);
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return ret;
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}
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EXPORT_SYMBOL(ftrace_print_hex_seq);
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int ftrace_raw_output_prep(struct trace_iterator *iter,
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struct trace_event *trace_event)
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{
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struct ftrace_event_call *event;
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struct trace_seq *s = &iter->seq;
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struct trace_seq *p = &iter->tmp_seq;
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struct trace_entry *entry;
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event = container_of(trace_event, struct ftrace_event_call, event);
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entry = iter->ent;
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if (entry->type != event->event.type) {
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WARN_ON_ONCE(1);
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return TRACE_TYPE_UNHANDLED;
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}
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trace_seq_init(p);
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trace_seq_printf(s, "%s: ", ftrace_event_name(event));
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return trace_handle_return(s);
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}
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EXPORT_SYMBOL(ftrace_raw_output_prep);
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static int ftrace_output_raw(struct trace_iterator *iter, char *name,
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char *fmt, va_list ap)
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{
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struct trace_seq *s = &iter->seq;
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trace_seq_printf(s, "%s: ", name);
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trace_seq_vprintf(s, fmt, ap);
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return trace_handle_return(s);
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}
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int ftrace_output_call(struct trace_iterator *iter, char *name, char *fmt, ...)
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{
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va_list ap;
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int ret;
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va_start(ap, fmt);
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ret = ftrace_output_raw(iter, name, fmt, ap);
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va_end(ap);
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return ret;
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}
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EXPORT_SYMBOL_GPL(ftrace_output_call);
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#ifdef CONFIG_KRETPROBES
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static inline const char *kretprobed(const char *name)
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{
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static const char tramp_name[] = "kretprobe_trampoline";
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int size = sizeof(tramp_name);
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if (strncmp(tramp_name, name, size) == 0)
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return "[unknown/kretprobe'd]";
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return name;
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}
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#else
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static inline const char *kretprobed(const char *name)
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{
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return name;
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}
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#endif /* CONFIG_KRETPROBES */
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static void
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seq_print_sym_short(struct trace_seq *s, const char *fmt, unsigned long address)
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{
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#ifdef CONFIG_KALLSYMS
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char str[KSYM_SYMBOL_LEN];
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const char *name;
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kallsyms_lookup(address, NULL, NULL, NULL, str);
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name = kretprobed(str);
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trace_seq_printf(s, fmt, name);
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#endif
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}
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static void
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seq_print_sym_offset(struct trace_seq *s, const char *fmt,
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unsigned long address)
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{
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#ifdef CONFIG_KALLSYMS
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char str[KSYM_SYMBOL_LEN];
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const char *name;
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sprint_symbol(str, address);
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name = kretprobed(str);
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trace_seq_printf(s, fmt, name);
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#endif
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}
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#ifndef CONFIG_64BIT
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# define IP_FMT "%08lx"
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#else
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# define IP_FMT "%016lx"
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#endif
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int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm,
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unsigned long ip, unsigned long sym_flags)
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{
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struct file *file = NULL;
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unsigned long vmstart = 0;
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int ret = 1;
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if (s->full)
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return 0;
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if (mm) {
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const struct vm_area_struct *vma;
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down_read(&mm->mmap_sem);
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vma = find_vma(mm, ip);
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if (vma) {
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file = vma->vm_file;
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vmstart = vma->vm_start;
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}
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if (file) {
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ret = trace_seq_path(s, &file->f_path);
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if (ret)
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trace_seq_printf(s, "[+0x%lx]",
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ip - vmstart);
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}
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up_read(&mm->mmap_sem);
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}
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if (ret && ((sym_flags & TRACE_ITER_SYM_ADDR) || !file))
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trace_seq_printf(s, " <" IP_FMT ">", ip);
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return !trace_seq_has_overflowed(s);
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}
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int
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seq_print_userip_objs(const struct userstack_entry *entry, struct trace_seq *s,
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unsigned long sym_flags)
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{
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struct mm_struct *mm = NULL;
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unsigned int i;
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if (trace_flags & TRACE_ITER_SYM_USEROBJ) {
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struct task_struct *task;
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/*
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* we do the lookup on the thread group leader,
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* since individual threads might have already quit!
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*/
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rcu_read_lock();
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task = find_task_by_vpid(entry->tgid);
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if (task)
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mm = get_task_mm(task);
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rcu_read_unlock();
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}
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for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
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unsigned long ip = entry->caller[i];
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if (ip == ULONG_MAX || trace_seq_has_overflowed(s))
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break;
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trace_seq_puts(s, " => ");
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if (!ip) {
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trace_seq_puts(s, "??");
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trace_seq_putc(s, '\n');
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continue;
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}
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seq_print_user_ip(s, mm, ip, sym_flags);
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trace_seq_putc(s, '\n');
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}
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if (mm)
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mmput(mm);
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return !trace_seq_has_overflowed(s);
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}
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int
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seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags)
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{
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if (!ip) {
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trace_seq_putc(s, '0');
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goto out;
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}
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if (sym_flags & TRACE_ITER_SYM_OFFSET)
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seq_print_sym_offset(s, "%s", ip);
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else
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seq_print_sym_short(s, "%s", ip);
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if (sym_flags & TRACE_ITER_SYM_ADDR)
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trace_seq_printf(s, " <" IP_FMT ">", ip);
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out:
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return !trace_seq_has_overflowed(s);
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}
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/**
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* trace_print_lat_fmt - print the irq, preempt and lockdep fields
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* @s: trace seq struct to write to
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* @entry: The trace entry field from the ring buffer
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*
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* Prints the generic fields of irqs off, in hard or softirq, preempt
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* count.
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*/
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int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
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{
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char hardsoft_irq;
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char need_resched;
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char irqs_off;
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int hardirq;
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int softirq;
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hardirq = entry->flags & TRACE_FLAG_HARDIRQ;
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softirq = entry->flags & TRACE_FLAG_SOFTIRQ;
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irqs_off =
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(entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' :
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(entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ? 'X' :
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'.';
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switch (entry->flags & (TRACE_FLAG_NEED_RESCHED |
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TRACE_FLAG_PREEMPT_RESCHED)) {
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case TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_PREEMPT_RESCHED:
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need_resched = 'N';
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break;
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case TRACE_FLAG_NEED_RESCHED:
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need_resched = 'n';
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break;
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case TRACE_FLAG_PREEMPT_RESCHED:
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need_resched = 'p';
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break;
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default:
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need_resched = '.';
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break;
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}
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hardsoft_irq =
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(hardirq && softirq) ? 'H' :
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hardirq ? 'h' :
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softirq ? 's' :
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'.';
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trace_seq_printf(s, "%c%c%c",
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irqs_off, need_resched, hardsoft_irq);
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if (entry->preempt_count)
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trace_seq_printf(s, "%x", entry->preempt_count);
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else
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trace_seq_putc(s, '.');
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return !trace_seq_has_overflowed(s);
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}
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static int
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lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
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{
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char comm[TASK_COMM_LEN];
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trace_find_cmdline(entry->pid, comm);
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trace_seq_printf(s, "%8.8s-%-5d %3d",
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comm, entry->pid, cpu);
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return trace_print_lat_fmt(s, entry);
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}
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#undef MARK
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#define MARK(v, s) {.val = v, .sym = s}
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/* trace overhead mark */
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static const struct trace_mark {
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unsigned long long val; /* unit: nsec */
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char sym;
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} mark[] = {
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MARK(1000000000ULL , '$'), /* 1 sec */
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MARK(1000000ULL , '#'), /* 1000 usecs */
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MARK(100000ULL , '!'), /* 100 usecs */
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MARK(10000ULL , '+'), /* 10 usecs */
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};
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#undef MARK
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char trace_find_mark(unsigned long long d)
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{
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int i;
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int size = ARRAY_SIZE(mark);
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for (i = 0; i < size; i++) {
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if (d >= mark[i].val)
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break;
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}
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return (i == size) ? ' ' : mark[i].sym;
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}
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static int
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lat_print_timestamp(struct trace_iterator *iter, u64 next_ts)
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{
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unsigned long verbose = trace_flags & TRACE_ITER_VERBOSE;
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unsigned long in_ns = iter->iter_flags & TRACE_FILE_TIME_IN_NS;
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unsigned long long abs_ts = iter->ts - iter->trace_buffer->time_start;
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unsigned long long rel_ts = next_ts - iter->ts;
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struct trace_seq *s = &iter->seq;
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if (in_ns) {
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abs_ts = ns2usecs(abs_ts);
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rel_ts = ns2usecs(rel_ts);
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}
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if (verbose && in_ns) {
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unsigned long abs_usec = do_div(abs_ts, USEC_PER_MSEC);
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unsigned long abs_msec = (unsigned long)abs_ts;
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unsigned long rel_usec = do_div(rel_ts, USEC_PER_MSEC);
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unsigned long rel_msec = (unsigned long)rel_ts;
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trace_seq_printf(
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s, "[%08llx] %ld.%03ldms (+%ld.%03ldms): ",
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ns2usecs(iter->ts),
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abs_msec, abs_usec,
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rel_msec, rel_usec);
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} else if (verbose && !in_ns) {
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trace_seq_printf(
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s, "[%016llx] %lld (+%lld): ",
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iter->ts, abs_ts, rel_ts);
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} else if (!verbose && in_ns) {
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trace_seq_printf(
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s, " %4lldus%c: ",
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abs_ts,
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trace_find_mark(rel_ts * NSEC_PER_USEC));
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} else { /* !verbose && !in_ns */
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trace_seq_printf(s, " %4lld: ", abs_ts);
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}
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|
|
return !trace_seq_has_overflowed(s);
|
|
}
|
|
|
|
int trace_print_context(struct trace_iterator *iter)
|
|
{
|
|
struct trace_seq *s = &iter->seq;
|
|
struct trace_entry *entry = iter->ent;
|
|
unsigned long long t;
|
|
unsigned long secs, usec_rem;
|
|
char comm[TASK_COMM_LEN];
|
|
|
|
trace_find_cmdline(entry->pid, comm);
|
|
|
|
trace_seq_printf(s, "%16s-%-5d [%03d] ",
|
|
comm, entry->pid, iter->cpu);
|
|
|
|
if (trace_flags & TRACE_ITER_IRQ_INFO)
|
|
trace_print_lat_fmt(s, entry);
|
|
|
|
if (iter->iter_flags & TRACE_FILE_TIME_IN_NS) {
|
|
t = ns2usecs(iter->ts);
|
|
usec_rem = do_div(t, USEC_PER_SEC);
|
|
secs = (unsigned long)t;
|
|
trace_seq_printf(s, " %5lu.%06lu: ", secs, usec_rem);
|
|
} else
|
|
trace_seq_printf(s, " %12llu: ", iter->ts);
|
|
|
|
return !trace_seq_has_overflowed(s);
|
|
}
|
|
|
|
int trace_print_lat_context(struct trace_iterator *iter)
|
|
{
|
|
u64 next_ts;
|
|
/* 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);
|
|
|
|
/* Restore the original ent_size */
|
|
iter->ent_size = ent_size;
|
|
|
|
if (!next_entry)
|
|
next_ts = iter->ts;
|
|
|
|
if (verbose) {
|
|
char comm[TASK_COMM_LEN];
|
|
|
|
trace_find_cmdline(entry->pid, comm);
|
|
|
|
trace_seq_printf(
|
|
s, "%16s %5d %3d %d %08x %08lx ",
|
|
comm, entry->pid, iter->cpu, entry->flags,
|
|
entry->preempt_count, iter->idx);
|
|
} else {
|
|
lat_print_generic(s, entry, iter->cpu);
|
|
}
|
|
|
|
lat_print_timestamp(iter, next_ts);
|
|
|
|
return !trace_seq_has_overflowed(s);
|
|
}
|
|
|
|
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] : '?';
|
|
}
|
|
|
|
/**
|
|
* ftrace_find_event - find a registered event
|
|
* @type: the type of event to look for
|
|
*
|
|
* Returns an event of type @type otherwise NULL
|
|
* Called with trace_event_read_lock() held.
|
|
*/
|
|
struct trace_event *ftrace_find_event(int type)
|
|
{
|
|
struct trace_event *event;
|
|
unsigned key;
|
|
|
|
key = type & (EVENT_HASHSIZE - 1);
|
|
|
|
hlist_for_each_entry(event, &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_sem);
|
|
}
|
|
|
|
void trace_event_read_unlock(void)
|
|
{
|
|
up_read(&trace_event_sem);
|
|
}
|
|
|
|
/**
|
|
* register_ftrace_event - register output for an event type
|
|
* @event: the event type to register
|
|
*
|
|
* Event types are stored in a hash and this hash is used to
|
|
* find a way to print an event. If the @event->type is set
|
|
* then it will use that type, otherwise it will assign a
|
|
* type to use.
|
|
*
|
|
* If you assign your own type, please make sure it is added
|
|
* to the trace_type enum in trace.h, to avoid collisions
|
|
* with the dynamic types.
|
|
*
|
|
* Returns the event type number or zero on error.
|
|
*/
|
|
int register_ftrace_event(struct trace_event *event)
|
|
{
|
|
unsigned key;
|
|
int ret = 0;
|
|
|
|
down_write(&trace_event_sem);
|
|
|
|
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_sem);
|
|
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL_GPL(register_ftrace_event);
|
|
|
|
/*
|
|
* Used by module code with the trace_event_sem held for write.
|
|
*/
|
|
int __unregister_ftrace_event(struct trace_event *event)
|
|
{
|
|
hlist_del(&event->node);
|
|
list_del(&event->list);
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* unregister_ftrace_event - remove a no longer used event
|
|
* @event: the event to remove
|
|
*/
|
|
int unregister_ftrace_event(struct trace_event *event)
|
|
{
|
|
down_write(&trace_event_sem);
|
|
__unregister_ftrace_event(event);
|
|
up_write(&trace_event_sem);
|
|
|
|
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)
|
|
{
|
|
trace_seq_printf(&iter->seq, "type: %d\n", iter->ent->type);
|
|
|
|
return trace_handle_return(&iter->seq);
|
|
}
|
|
|
|
/* 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);
|
|
|
|
seq_print_ip_sym(s, field->ip, flags);
|
|
|
|
if ((flags & TRACE_ITER_PRINT_PARENT) && field->parent_ip) {
|
|
trace_seq_puts(s, " <-");
|
|
seq_print_ip_sym(s, field->parent_ip, flags);
|
|
}
|
|
|
|
trace_seq_putc(s, '\n');
|
|
|
|
return trace_handle_return(s);
|
|
}
|
|
|
|
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);
|
|
|
|
trace_seq_printf(&iter->seq, "%lx %lx\n",
|
|
field->ip,
|
|
field->parent_ip);
|
|
|
|
return trace_handle_return(&iter->seq);
|
|
}
|
|
|
|
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(s, field->ip);
|
|
SEQ_PUT_HEX_FIELD(s, field->parent_ip);
|
|
|
|
return trace_handle_return(s);
|
|
}
|
|
|
|
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(s, field->ip);
|
|
SEQ_PUT_FIELD(s, field->parent_ip);
|
|
|
|
return trace_handle_return(s);
|
|
}
|
|
|
|
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);
|
|
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_handle_return(&iter->seq);
|
|
}
|
|
|
|
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);
|
|
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_handle_return(&iter->seq);
|
|
}
|
|
|
|
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(s, field->prev_pid);
|
|
SEQ_PUT_HEX_FIELD(s, field->prev_prio);
|
|
SEQ_PUT_HEX_FIELD(s, S);
|
|
SEQ_PUT_HEX_FIELD(s, field->next_cpu);
|
|
SEQ_PUT_HEX_FIELD(s, field->next_pid);
|
|
SEQ_PUT_HEX_FIELD(s, field->next_prio);
|
|
SEQ_PUT_HEX_FIELD(s, T);
|
|
|
|
return trace_handle_return(s);
|
|
}
|
|
|
|
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(s, field->prev_pid);
|
|
SEQ_PUT_FIELD(s, field->prev_prio);
|
|
SEQ_PUT_FIELD(s, field->prev_state);
|
|
SEQ_PUT_FIELD(s, field->next_cpu);
|
|
SEQ_PUT_FIELD(s, field->next_pid);
|
|
SEQ_PUT_FIELD(s, field->next_prio);
|
|
SEQ_PUT_FIELD(s, field->next_state);
|
|
|
|
return trace_handle_return(s);
|
|
}
|
|
|
|
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);
|
|
|
|
trace_seq_puts(s, "<stack trace>\n");
|
|
|
|
for (p = field->caller; p && *p != ULONG_MAX && p < end; p++) {
|
|
|
|
if (trace_seq_has_overflowed(s))
|
|
break;
|
|
|
|
trace_seq_puts(s, " => ");
|
|
seq_print_ip_sym(s, *p, flags);
|
|
trace_seq_putc(s, '\n');
|
|
}
|
|
|
|
return trace_handle_return(s);
|
|
}
|
|
|
|
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);
|
|
|
|
trace_seq_puts(s, "<user stack trace>\n");
|
|
seq_print_userip_objs(field, s, flags);
|
|
|
|
return trace_handle_return(s);
|
|
}
|
|
|
|
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_BPUTS */
|
|
static enum print_line_t
|
|
trace_bputs_print(struct trace_iterator *iter, int flags,
|
|
struct trace_event *event)
|
|
{
|
|
struct trace_entry *entry = iter->ent;
|
|
struct trace_seq *s = &iter->seq;
|
|
struct bputs_entry *field;
|
|
|
|
trace_assign_type(field, entry);
|
|
|
|
seq_print_ip_sym(s, field->ip, flags);
|
|
trace_seq_puts(s, ": ");
|
|
trace_seq_puts(s, field->str);
|
|
|
|
return trace_handle_return(s);
|
|
}
|
|
|
|
|
|
static enum print_line_t
|
|
trace_bputs_raw(struct trace_iterator *iter, int flags,
|
|
struct trace_event *event)
|
|
{
|
|
struct bputs_entry *field;
|
|
struct trace_seq *s = &iter->seq;
|
|
|
|
trace_assign_type(field, iter->ent);
|
|
|
|
trace_seq_printf(s, ": %lx : ", field->ip);
|
|
trace_seq_puts(s, field->str);
|
|
|
|
return trace_handle_return(s);
|
|
}
|
|
|
|
static struct trace_event_functions trace_bputs_funcs = {
|
|
.trace = trace_bputs_print,
|
|
.raw = trace_bputs_raw,
|
|
};
|
|
|
|
static struct trace_event trace_bputs_event = {
|
|
.type = TRACE_BPUTS,
|
|
.funcs = &trace_bputs_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);
|
|
|
|
seq_print_ip_sym(s, field->ip, flags);
|
|
trace_seq_puts(s, ": ");
|
|
trace_seq_bprintf(s, field->fmt, field->buf);
|
|
|
|
return trace_handle_return(s);
|
|
}
|
|
|
|
|
|
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);
|
|
|
|
trace_seq_printf(s, ": %lx : ", field->ip);
|
|
trace_seq_bprintf(s, field->fmt, field->buf);
|
|
|
|
return trace_handle_return(s);
|
|
}
|
|
|
|
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);
|
|
|
|
seq_print_ip_sym(s, field->ip, flags);
|
|
trace_seq_printf(s, ": %s", field->buf);
|
|
|
|
return trace_handle_return(s);
|
|
}
|
|
|
|
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);
|
|
|
|
trace_seq_printf(&iter->seq, "# %lx %s", field->ip, field->buf);
|
|
|
|
return trace_handle_return(&iter->seq);
|
|
}
|
|
|
|
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_bputs_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);
|