tracing: Move the trace_seq_* functions into its own trace_seq.c file

rostedt · rostedt · commit 12306276fabc · 2014-07-01T07:13:35.000-04:00
The trace_seq_*() functions are a nice utility that allows users to manipulate
buffers with printf() like formats. It has its own trace_seq.h header in
include/linux and should be in its own file. Being tied with trace_output.c
is rather awkward.

Signed-off-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
diff --git a/include/linux/trace_seq.h b/include/linux/trace_seq.h
@@ -25,6 +25,8 @@ trace_seq_init(struct trace_seq *s)
 	s->full = 0;
 }
 
+#define MAX_MEMHEX_BYTES	8
+
 /*
  * Currently only defined when tracing is enabled.
  */
diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile
@@ -28,6 +28,7 @@ obj-$(CONFIG_RING_BUFFER_BENCHMARK) += ring_buffer_benchmark.o
 
 obj-$(CONFIG_TRACING) += trace.o
 obj-$(CONFIG_TRACING) += trace_output.o
+obj-$(CONFIG_TRACING) += trace_seq.o
 obj-$(CONFIG_TRACING) += trace_stat.o
 obj-$(CONFIG_TRACING) += trace_printk.o
 obj-$(CONFIG_CONTEXT_SWITCH_TRACER) += trace_sched_switch.o
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
@@ -923,30 +923,6 @@ int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
 	return ret;
 }
 
-ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt)
-{
-	int len;
-	int ret;
-
-	if (!cnt)
-		return 0;
-
-	if (s->len <= s->readpos)
-		return -EBUSY;
-
-	len = s->len - s->readpos;
-	if (cnt > len)
-		cnt = len;
-	ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt);
-	if (ret == cnt)
-		return -EFAULT;
-
-	cnt -= ret;
-
-	s->readpos += cnt;
-	return cnt;
-}
-
 static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt)
 {
 	int len;
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
@@ -20,23 +20,6 @@ static struct hlist_head event_hash[EVENT_HASHSIZE] __read_mostly;
 
 static int next_event_type = __TRACE_LAST_TYPE + 1;
 
-int trace_print_seq(struct seq_file *m, struct trace_seq *s)
-{
-	int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len;
-	int ret;
-
-	ret = seq_write(m, s->buffer, len);
-
-	/*
-	 * Only reset this buffer if we successfully wrote to the
-	 * seq_file buffer.
-	 */
-	if (!ret)
-		trace_seq_init(s);
-
-	return ret;
-}
-
 enum print_line_t trace_print_bputs_msg_only(struct trace_iterator *iter)
 {
 	struct trace_seq *s = &iter->seq;
@@ -85,257 +68,6 @@ enum print_line_t trace_print_printk_msg_only(struct trace_iterator *iter)
 	return TRACE_TYPE_HANDLED;
 }
 
-/**
- * trace_seq_printf - sequence printing of trace information
- * @s: trace sequence descriptor
- * @fmt: printf format string
- *
- * It returns 0 if the trace oversizes the buffer's free
- * space, 1 otherwise.
- *
- * The tracer may use either sequence operations or its own
- * copy to user routines. To simplify formating of a trace
- * trace_seq_printf is used to store strings into a special
- * buffer (@s). Then the output may be either used by
- * the sequencer or pulled into another buffer.
- */
-int
-trace_seq_printf(struct trace_seq *s, const char *fmt, ...)
-{
-	int len = (PAGE_SIZE - 1) - s->len;
-	va_list ap;
-	int ret;
-
-	if (s->full || !len)
-		return 0;
-
-	va_start(ap, fmt);
-	ret = vsnprintf(s->buffer + s->len, len, fmt, ap);
-	va_end(ap);
-
-	/* If we can't write it all, don't bother writing anything */
-	if (ret >= len) {
-		s->full = 1;
-		return 0;
-	}
-
-	s->len += ret;
-
-	return 1;
-}
-EXPORT_SYMBOL_GPL(trace_seq_printf);
-
-/**
- * trace_seq_bitmask - put a list of longs as a bitmask print output
- * @s:		trace sequence descriptor
- * @maskp:	points to an array of unsigned longs that represent a bitmask
- * @nmaskbits:	The number of bits that are valid in @maskp
- *
- * It returns 0 if the trace oversizes the buffer's free
- * space, 1 otherwise.
- *
- * Writes a ASCII representation of a bitmask string into @s.
- */
-int
-trace_seq_bitmask(struct trace_seq *s, const unsigned long *maskp,
-		  int nmaskbits)
-{
-	int len = (PAGE_SIZE - 1) - s->len;
-	int ret;
-
-	if (s->full || !len)
-		return 0;
-
-	ret = bitmap_scnprintf(s->buffer, len, maskp, nmaskbits);
-	s->len += ret;
-
-	return 1;
-}
-EXPORT_SYMBOL_GPL(trace_seq_bitmask);
-
-/**
- * trace_seq_vprintf - sequence printing of trace information
- * @s: trace sequence descriptor
- * @fmt: printf format string
- *
- * The tracer may use either sequence operations or its own
- * copy to user routines. To simplify formating of a trace
- * trace_seq_printf is used to store strings into a special
- * buffer (@s). Then the output may be either used by
- * the sequencer or pulled into another buffer.
- */
-int
-trace_seq_vprintf(struct trace_seq *s, const char *fmt, va_list args)
-{
-	int len = (PAGE_SIZE - 1) - s->len;
-	int ret;
-
-	if (s->full || !len)
-		return 0;
-
-	ret = vsnprintf(s->buffer + s->len, len, fmt, args);
-
-	/* If we can't write it all, don't bother writing anything */
-	if (ret >= len) {
-		s->full = 1;
-		return 0;
-	}
-
-	s->len += ret;
-
-	return len;
-}
-EXPORT_SYMBOL_GPL(trace_seq_vprintf);
-
-int trace_seq_bprintf(struct trace_seq *s, const char *fmt, const u32 *binary)
-{
-	int len = (PAGE_SIZE - 1) - s->len;
-	int ret;
-
-	if (s->full || !len)
-		return 0;
-
-	ret = bstr_printf(s->buffer + s->len, len, fmt, binary);
-
-	/* If we can't write it all, don't bother writing anything */
-	if (ret >= len) {
-		s->full = 1;
-		return 0;
-	}
-
-	s->len += ret;
-
-	return len;
-}
-
-/**
- * trace_seq_puts - trace sequence printing of simple string
- * @s: trace sequence descriptor
- * @str: simple string to record
- *
- * The tracer may use either the sequence operations or its own
- * copy to user routines. This function records a simple string
- * into a special buffer (@s) for later retrieval by a sequencer
- * or other mechanism.
- */
-int trace_seq_puts(struct trace_seq *s, const char *str)
-{
-	int len = strlen(str);
-
-	if (s->full)
-		return 0;
-
-	if (len > ((PAGE_SIZE - 1) - s->len)) {
-		s->full = 1;
-		return 0;
-	}
-
-	memcpy(s->buffer + s->len, str, len);
-	s->len += len;
-
-	return len;
-}
-
-int trace_seq_putc(struct trace_seq *s, unsigned char c)
-{
-	if (s->full)
-		return 0;
-
-	if (s->len >= (PAGE_SIZE - 1)) {
-		s->full = 1;
-		return 0;
-	}
-
-	s->buffer[s->len++] = c;
-
-	return 1;
-}
-EXPORT_SYMBOL(trace_seq_putc);
-
-int trace_seq_putmem(struct trace_seq *s, const void *mem, size_t len)
-{
-	if (s->full)
-		return 0;
-
-	if (len > ((PAGE_SIZE - 1) - s->len)) {
-		s->full = 1;
-		return 0;
-	}
-
-	memcpy(s->buffer + s->len, mem, len);
-	s->len += len;
-
-	return len;
-}
-
-int trace_seq_putmem_hex(struct trace_seq *s, const void *mem, size_t len)
-{
-	unsigned char hex[HEX_CHARS];
-	const unsigned char *data = mem;
-	int i, j;
-
-	if (s->full)
-		return 0;
-
-#ifdef __BIG_ENDIAN
-	for (i = 0, j = 0; i < len; i++) {
-#else
-	for (i = len-1, j = 0; i >= 0; i--) {
-#endif
-		hex[j++] = hex_asc_hi(data[i]);
-		hex[j++] = hex_asc_lo(data[i]);
-	}
-	hex[j++] = ' ';
-
-	return trace_seq_putmem(s, hex, j);
-}
-
-void *trace_seq_reserve(struct trace_seq *s, size_t len)
-{
-	void *ret;
-
-	if (s->full)
-		return NULL;
-
-	if (len > ((PAGE_SIZE - 1) - s->len)) {
-		s->full = 1;
-		return NULL;
-	}
-
-	ret = s->buffer + s->len;
-	s->len += len;
-
-	return ret;
-}
-
-int trace_seq_path(struct trace_seq *s, const struct path *path)
-{
-	unsigned char *p;
-
-	if (s->full)
-		return 0;
-
-	if (s->len >= (PAGE_SIZE - 1)) {
-		s->full = 1;
-		return 0;
-	}
-
-	p = d_path(path, s->buffer + s->len, PAGE_SIZE - s->len);
-	if (!IS_ERR(p)) {
-		p = mangle_path(s->buffer + s->len, p, "\n");
-		if (p) {
-			s->len = p - s->buffer;
-			return 1;
-		}
-	} else {
-		s->buffer[s->len++] = '?';
-		return 1;
-	}
-
-	s->full = 1;
-	return 0;
-}
-
 const char *
 ftrace_print_flags_seq(struct trace_seq *p, const char *delim,
 		       unsigned long flags,
diff --git a/kernel/trace/trace_output.h b/kernel/trace/trace_output.h
@@ -35,9 +35,6 @@ trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry);
 extern int __unregister_ftrace_event(struct trace_event *event);
 extern struct rw_semaphore trace_event_sem;
 
-#define MAX_MEMHEX_BYTES	8
-#define HEX_CHARS		(MAX_MEMHEX_BYTES*2 + 1)
-
 #define SEQ_PUT_FIELD_RET(s, x)				\
 do {							\
 	if (!trace_seq_putmem(s, &(x), sizeof(x)))	\
diff --git a/kernel/trace/trace_seq.c b/kernel/trace/trace_seq.c

Original file line number	Diff line number	Diff line change
`@@ -25,6 +25,8 @@ trace_seq_init(struct trace_seq *s)`
`25`	`25`	`s->full = 0;`
`26`	`26`	`}`
`27`	`27`
	`28`	`+#define MAX_MEMHEX_BYTES 8`
	`29`	`+`
`28`	`30`	`/*`
`29`	`31`	`* Currently only defined when tracing is enabled.`
`30`	`32`	`*/`