db4c75cbeb
While debugging a latency with someone on IRC (mirage335) on #linux-rt (OFTC),
we discovered that the stacktrace output of the latency tracers
(preemptirqsoff) was empty.
This bug was caused by the creation of the dynamic length stack trace
again (like commit 12b5da3 "tracing: Fix ent_size in trace output" was).
This bug is caused by the latency tracers requiring the next event
to determine the time between the current event and the next. But by
grabbing the next event, the iter->ent_size is set to the next event
instead of the current one. As the stacktrace event is the last event,
this makes the ent_size zero and causes nothing to be printed for
the stack trace. The dynamic stacktrace uses the ent_size to determine
how much of the stack can be printed. The ent_size of zero means
no stack.
The simple fix is to save the iter->ent_size before finding the next event.
Note, mirage335 asked to remain anonymous from LKML and git, so I will
not add the Reported-by and Tested-by tags, even though he did report
the issue and tested the fix.
Cc: stable@vger.kernel.org # 3.1+
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
1329 lines
28 KiB
C
1329 lines
28 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_mutex);
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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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int trace_print_seq(struct seq_file *m, struct trace_seq *s)
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{
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int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len;
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int ret;
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ret = seq_write(m, s->buffer, len);
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/*
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* Only reset this buffer if we successfully wrote to the
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* seq_file buffer.
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*/
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if (!ret)
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trace_seq_init(s);
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return ret;
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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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int ret;
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trace_assign_type(field, entry);
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ret = trace_seq_bprintf(s, field->fmt, field->buf);
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if (!ret)
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return TRACE_TYPE_PARTIAL_LINE;
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return TRACE_TYPE_HANDLED;
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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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int ret;
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trace_assign_type(field, entry);
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ret = trace_seq_printf(s, "%s", field->buf);
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if (!ret)
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return TRACE_TYPE_PARTIAL_LINE;
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return TRACE_TYPE_HANDLED;
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}
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/**
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* trace_seq_printf - sequence printing of trace information
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* @s: trace sequence descriptor
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* @fmt: printf format string
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*
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* It returns 0 if the trace oversizes the buffer's free
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* space, 1 otherwise.
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*
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* The tracer may use either sequence operations or its own
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* copy to user routines. To simplify formating of a trace
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* trace_seq_printf is used to store strings into a special
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* buffer (@s). Then the output may be either used by
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* the sequencer or pulled into another buffer.
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*/
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int
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trace_seq_printf(struct trace_seq *s, const char *fmt, ...)
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{
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int len = (PAGE_SIZE - 1) - s->len;
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va_list ap;
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int ret;
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if (s->full || !len)
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return 0;
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va_start(ap, fmt);
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ret = vsnprintf(s->buffer + s->len, len, fmt, ap);
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va_end(ap);
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/* If we can't write it all, don't bother writing anything */
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if (ret >= len) {
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s->full = 1;
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return 0;
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}
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s->len += ret;
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return 1;
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}
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EXPORT_SYMBOL_GPL(trace_seq_printf);
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/**
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* trace_seq_vprintf - sequence printing of trace information
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* @s: trace sequence descriptor
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* @fmt: printf format string
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*
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* The tracer may use either sequence operations or its own
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* copy to user routines. To simplify formating of a trace
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* trace_seq_printf is used to store strings into a special
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* buffer (@s). Then the output may be either used by
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* the sequencer or pulled into another buffer.
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*/
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int
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trace_seq_vprintf(struct trace_seq *s, const char *fmt, va_list args)
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{
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int len = (PAGE_SIZE - 1) - s->len;
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int ret;
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if (s->full || !len)
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return 0;
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ret = vsnprintf(s->buffer + s->len, len, fmt, args);
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/* If we can't write it all, don't bother writing anything */
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if (ret >= len) {
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s->full = 1;
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return 0;
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}
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s->len += ret;
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return len;
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}
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EXPORT_SYMBOL_GPL(trace_seq_vprintf);
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int trace_seq_bprintf(struct trace_seq *s, const char *fmt, const u32 *binary)
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{
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int len = (PAGE_SIZE - 1) - s->len;
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int ret;
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if (s->full || !len)
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return 0;
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ret = bstr_printf(s->buffer + s->len, len, fmt, binary);
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/* If we can't write it all, don't bother writing anything */
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if (ret >= len) {
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s->full = 1;
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return 0;
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}
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s->len += ret;
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return len;
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}
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/**
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* trace_seq_puts - trace sequence printing of simple string
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* @s: trace sequence descriptor
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* @str: simple string to record
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*
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* The tracer may use either the sequence operations or its own
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* copy to user routines. This function records a simple string
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* into a special buffer (@s) for later retrieval by a sequencer
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* or other mechanism.
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*/
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int trace_seq_puts(struct trace_seq *s, const char *str)
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{
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int len = strlen(str);
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if (s->full)
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return 0;
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if (len > ((PAGE_SIZE - 1) - s->len)) {
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s->full = 1;
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return 0;
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}
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memcpy(s->buffer + s->len, str, len);
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s->len += len;
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return len;
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}
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int trace_seq_putc(struct trace_seq *s, unsigned char c)
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{
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if (s->full)
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return 0;
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if (s->len >= (PAGE_SIZE - 1)) {
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s->full = 1;
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return 0;
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}
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s->buffer[s->len++] = c;
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return 1;
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}
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EXPORT_SYMBOL(trace_seq_putc);
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int trace_seq_putmem(struct trace_seq *s, const void *mem, size_t len)
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{
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if (s->full)
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return 0;
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if (len > ((PAGE_SIZE - 1) - s->len)) {
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s->full = 1;
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return 0;
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}
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memcpy(s->buffer + s->len, mem, len);
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s->len += len;
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return len;
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}
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int trace_seq_putmem_hex(struct trace_seq *s, const void *mem, size_t len)
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{
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unsigned char hex[HEX_CHARS];
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const unsigned char *data = mem;
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int i, j;
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if (s->full)
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return 0;
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#ifdef __BIG_ENDIAN
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for (i = 0, j = 0; i < len; i++) {
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#else
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for (i = len-1, j = 0; i >= 0; i--) {
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#endif
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hex[j++] = hex_asc_hi(data[i]);
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hex[j++] = hex_asc_lo(data[i]);
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}
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hex[j++] = ' ';
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return trace_seq_putmem(s, hex, j);
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}
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void *trace_seq_reserve(struct trace_seq *s, size_t len)
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{
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void *ret;
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if (s->full)
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return NULL;
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if (len > ((PAGE_SIZE - 1) - s->len)) {
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s->full = 1;
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return NULL;
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}
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ret = s->buffer + s->len;
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s->len += len;
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return ret;
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}
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int trace_seq_path(struct trace_seq *s, const struct path *path)
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{
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unsigned char *p;
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if (s->full)
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return 0;
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if (s->len >= (PAGE_SIZE - 1)) {
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s->full = 1;
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return 0;
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}
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p = d_path(path, s->buffer + s->len, PAGE_SIZE - s->len);
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if (!IS_ERR(p)) {
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p = mangle_path(s->buffer + s->len, p, "\n");
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if (p) {
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s->len = p - s->buffer;
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return 1;
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}
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} else {
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s->buffer[s->len++] = '?';
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return 1;
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}
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s->full = 1;
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return 0;
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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 = p->buffer + p->len;
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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 = p->buffer + p->len;
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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 *)(p->buffer + p->len))
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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 = p->buffer + p->len;
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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 *)(p->buffer + p->len))
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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_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 = p->buffer + p->len;
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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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#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 int
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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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return trace_seq_printf(s, fmt, name);
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#endif
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return 1;
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}
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static int
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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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return trace_seq_printf(s, fmt, name);
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#endif
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return 1;
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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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ret = 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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ret = trace_seq_printf(s, " <" IP_FMT ">", ip);
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return ret;
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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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int ret = 1;
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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 || !ret)
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break;
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if (ret)
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ret = trace_seq_puts(s, " => ");
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if (!ip) {
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if (ret)
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ret = trace_seq_puts(s, "??");
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if (ret)
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ret = trace_seq_puts(s, "\n");
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continue;
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}
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if (!ret)
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break;
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if (ret)
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ret = seq_print_user_ip(s, mm, ip, sym_flags);
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ret = trace_seq_puts(s, "\n");
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}
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if (mm)
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mmput(mm);
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return ret;
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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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int ret;
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if (!ip)
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return trace_seq_printf(s, "0");
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if (sym_flags & TRACE_ITER_SYM_OFFSET)
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ret = seq_print_sym_offset(s, "%s", ip);
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else
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ret = seq_print_sym_short(s, "%s", ip);
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if (!ret)
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return 0;
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if (sym_flags & TRACE_ITER_SYM_ADDR)
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ret = trace_seq_printf(s, " <" IP_FMT ">", ip);
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return ret;
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}
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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
|
|
* count.
|
|
*/
|
|
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] : '?';
|
|
}
|
|
|
|
/**
|
|
* 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;
|
|
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);
|
|
}
|
|
|
|
/**
|
|
* 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_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;
|
|
}
|
|
|
|
/**
|
|
* 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_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;
|
|
}
|
|
device_initcall(init_events);
|