Commit 7b039cb4 authored by Steven Rostedt (Red Hat)'s avatar Steven Rostedt (Red Hat) Committed by Steven Rostedt
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tracing: Add trace_seq_buffer_ptr() helper function 

There's several locations in the kernel that open code the calculation
of the next location in the trace_seq buffer. This is usually done with

  p->buffer + p->len

Instead of having this open coded, supply a helper function in the
header to do it for them. This function is called trace_seq_buffer_ptr().

Link: http://lkml.kernel.org/p/20140626220129.452783019@goodmis.org



Acked-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
parent 3f4d8f78

arch/x86/kvm/mmutrace.h

+1 −1
Original line number Diff line number Diff line
@@ -22,7 +22,7 @@ 
	__entry->unsync = sp->unsync;



#define KVM_MMU_PAGE_PRINTK() ({				        \

	const char *ret = p->buffer + p->len;				\

	const char *ret = trace_seq_buffer_ptr(p);			\

	static const char *access_str[] = {			        \

		"---", "--x", "w--", "w-x", "-u-", "-ux", "wu-", "wux"  \

	};							        \

drivers/scsi/scsi_trace.c

+8 −8
Original line number Diff line number Diff line
@@ -28,7 +28,7 @@ scsi_trace_misc(struct trace_seq *, unsigned char *, int); 
static const char *

scsi_trace_rw6(struct trace_seq *p, unsigned char *cdb, int len)

{

	const char *ret = p->buffer + p->len;

	const char *ret = trace_seq_buffer_ptr(p);

	sector_t lba = 0, txlen = 0;



	lba |= ((cdb[1] & 0x1F) << 16);
@@ -46,7 +46,7 @@ scsi_trace_rw6(struct trace_seq *p, unsigned char *cdb, int len) 
static const char *

scsi_trace_rw10(struct trace_seq *p, unsigned char *cdb, int len)

{

	const char *ret = p->buffer + p->len;

	const char *ret = trace_seq_buffer_ptr(p);

	sector_t lba = 0, txlen = 0;



	lba |= (cdb[2] << 24);
@@ -71,7 +71,7 @@ scsi_trace_rw10(struct trace_seq *p, unsigned char *cdb, int len) 
static const char *

scsi_trace_rw12(struct trace_seq *p, unsigned char *cdb, int len)

{

	const char *ret = p->buffer + p->len;

	const char *ret = trace_seq_buffer_ptr(p);

	sector_t lba = 0, txlen = 0;



	lba |= (cdb[2] << 24);
@@ -94,7 +94,7 @@ scsi_trace_rw12(struct trace_seq *p, unsigned char *cdb, int len) 
static const char *

scsi_trace_rw16(struct trace_seq *p, unsigned char *cdb, int len)

{

	const char *ret = p->buffer + p->len;

	const char *ret = trace_seq_buffer_ptr(p);

	sector_t lba = 0, txlen = 0;



	lba |= ((u64)cdb[2] << 56);
@@ -125,7 +125,7 @@ scsi_trace_rw16(struct trace_seq *p, unsigned char *cdb, int len) 
static const char *

scsi_trace_rw32(struct trace_seq *p, unsigned char *cdb, int len)

{

	const char *ret = p->buffer + p->len, *cmd;

	const char *ret = trace_seq_buffer_ptr(p), *cmd;

	sector_t lba = 0, txlen = 0;

	u32 ei_lbrt = 0;
@@ -180,7 +180,7 @@ out: 
static const char *

scsi_trace_unmap(struct trace_seq *p, unsigned char *cdb, int len)

{

	const char *ret = p->buffer + p->len;

	const char *ret = trace_seq_buffer_ptr(p);

	unsigned int regions = cdb[7] << 8 | cdb[8];



	trace_seq_printf(p, "regions=%u", (regions - 8) / 16);
@@ -192,7 +192,7 @@ scsi_trace_unmap(struct trace_seq *p, unsigned char *cdb, int len) 
static const char *

scsi_trace_service_action_in(struct trace_seq *p, unsigned char *cdb, int len)

{

	const char *ret = p->buffer + p->len, *cmd;

	const char *ret = trace_seq_buffer_ptr(p), *cmd;

	sector_t lba = 0;

	u32 alloc_len = 0;
@@ -247,7 +247,7 @@ scsi_trace_varlen(struct trace_seq *p, unsigned char *cdb, int len) 
static const char *

scsi_trace_misc(struct trace_seq *p, unsigned char *cdb, int len)

{

	const char *ret = p->buffer + p->len;

	const char *ret = trace_seq_buffer_ptr(p);



	trace_seq_printf(p, "-");

	trace_seq_putc(p, 0);

include/linux/trace_seq.h

+15 −0
Original line number Diff line number Diff line
@@ -25,6 +25,21 @@ trace_seq_init(struct trace_seq *s) 
	s->full = 0;

}



/**

 * trace_seq_buffer_ptr - return pointer to next location in buffer

 * @s: trace sequence descriptor

 *

 * Returns the pointer to the buffer where the next write to

 * the buffer will happen. This is useful to save the location

 * that is about to be written to and then return the result

 * of that write.

 */

static inline unsigned char *

trace_seq_buffer_ptr(struct trace_seq *s)

{

	return s->buffer + s->len;

}



/*

 * Currently only defined when tracing is enabled.

 */

kernel/trace/trace_output.c

+7 −7
Original line number Diff line number Diff line
@@ -75,7 +75,7 @@ ftrace_print_flags_seq(struct trace_seq *p, const char *delim, 
{

	unsigned long mask;

	const char *str;

	const char *ret = p->buffer + p->len;

	const char *ret = trace_seq_buffer_ptr(p);

	int i, first = 1;



	for (i = 0;  flag_array[i].name && flags; i++) {
@@ -111,7 +111,7 @@ ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val, 
			 const struct trace_print_flags *symbol_array)

{

	int i;

	const char *ret = p->buffer + p->len;

	const char *ret = trace_seq_buffer_ptr(p);



	for (i = 0;  symbol_array[i].name; i++) {
@@ -122,7 +122,7 @@ ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val, 
		break;

	}



	if (ret == (const char *)(p->buffer + p->len))

	if (ret == (const char *)(trace_seq_buffer_ptr(p)))

		trace_seq_printf(p, "0x%lx", val);

		

	trace_seq_putc(p, 0);
@@ -137,7 +137,7 @@ ftrace_print_symbols_seq_u64(struct trace_seq *p, unsigned long long val, 
			 const struct trace_print_flags_u64 *symbol_array)

{

	int i;

	const char *ret = p->buffer + p->len;

	const char *ret = trace_seq_buffer_ptr(p);



	for (i = 0;  symbol_array[i].name; i++) {
@@ -148,7 +148,7 @@ ftrace_print_symbols_seq_u64(struct trace_seq *p, unsigned long long val, 
		break;

	}



	if (ret == (const char *)(p->buffer + p->len))

	if (ret == (const char *)(trace_seq_buffer_ptr(p)))

		trace_seq_printf(p, "0x%llx", val);



	trace_seq_putc(p, 0);
@@ -162,7 +162,7 @@ const char * 
ftrace_print_bitmask_seq(struct trace_seq *p, void *bitmask_ptr,

			 unsigned int bitmask_size)

{

	const char *ret = p->buffer + p->len;

	const char *ret = trace_seq_buffer_ptr(p);



	trace_seq_bitmask(p, bitmask_ptr, bitmask_size * 8);

	trace_seq_putc(p, 0);
@@ -175,7 +175,7 @@ const char * 
ftrace_print_hex_seq(struct trace_seq *p, const unsigned char *buf, int buf_len)

{

	int i;

	const char *ret = p->buffer + p->len;

	const char *ret = trace_seq_buffer_ptr(p);



	for (i = 0; i < buf_len; i++)

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

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