[deliverable/linux.git] / arch / arm / oprofile / common.c

/**
 * @file common.c
 *
 * @remark Copyright 2004 Oprofile Authors
 * @remark Copyright 2010 ARM Ltd.
 * @remark Read the file COPYING
 *
 * @author Zwane Mwaikambo
 * @author Will Deacon [move to perf]
 */

#include <linux/cpumask.h>
#include <linux/init.h>
#include <linux/mutex.h>
#include <linux/oprofile.h>
#include <linux/perf_event.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <asm/stacktrace.h>
#include <linux/uaccess.h>

#include <asm/perf_event.h>
#include <asm/ptrace.h>

#ifdef CONFIG_HW_PERF_EVENTS
char *op_name_from_perf_id(void)
{
	enum arm_perf_pmu_ids id = armpmu_get_pmu_id();

	switch (id) {
	case ARM_PERF_PMU_ID_XSCALE1:
		return "arm/xscale1";
	case ARM_PERF_PMU_ID_XSCALE2:
		return "arm/xscale2";
	case ARM_PERF_PMU_ID_V6:
		return "arm/armv6";
	case ARM_PERF_PMU_ID_V6MP:
		return "arm/mpcore";
	case ARM_PERF_PMU_ID_CA8:
		return "arm/armv7";
	case ARM_PERF_PMU_ID_CA9:
		return "arm/armv7-ca9";
	default:
		return NULL;
	}
}
#endif

static int report_trace(struct stackframe *frame, void *d)
{
	unsigned int *depth = d;

	if (*depth) {
		oprofile_add_trace(frame->pc);
		(*depth)--;
	}

	return *depth == 0;
}

/*
 * The registers we're interested in are at the end of the variable
 * length saved register structure. The fp points at the end of this
 * structure so the address of this struct is:
 * (struct frame_tail *)(xxx->fp)-1
 */
struct frame_tail {
	struct frame_tail *fp;
	unsigned long sp;
	unsigned long lr;
} __attribute__((packed));

static struct frame_tail* user_backtrace(struct frame_tail *tail)
{
	struct frame_tail buftail[2];

	/* Also check accessibility of one struct frame_tail beyond */
	if (!access_ok(VERIFY_READ, tail, sizeof(buftail)))
		return NULL;
	if (__copy_from_user_inatomic(buftail, tail, sizeof(buftail)))
		return NULL;

	oprofile_add_trace(buftail[0].lr);

	/* frame pointers should strictly progress back up the stack
	 * (towards higher addresses) */
	if (tail + 1 >= buftail[0].fp)
		return NULL;

	return buftail[0].fp-1;
}

static void arm_backtrace(struct pt_regs * const regs, unsigned int depth)
{
	struct frame_tail *tail = ((struct frame_tail *) regs->ARM_fp) - 1;

	if (!user_mode(regs)) {
		struct stackframe frame;
		frame.fp = regs->ARM_fp;
		frame.sp = regs->ARM_sp;
		frame.lr = regs->ARM_lr;
		frame.pc = regs->ARM_pc;
		walk_stackframe(&frame, report_trace, &depth);
		return;
	}

	while (depth-- && tail && !((unsigned long) tail & 3))
		tail = user_backtrace(tail);
}

int __init oprofile_arch_init(struct oprofile_operations *ops)
{
	/* provide backtrace support also in timer mode: */
	ops->backtrace		= arm_backtrace;

	return oprofile_perf_init(ops);
}

void __exit oprofile_arch_exit(void)
{
	oprofile_perf_exit();
}
Commit	Line	Data
1da177e4 LT	1	/**
	2	* @file common.c
	3	*
	4	* @remark Copyright 2004 Oprofile Authors
8c1fc96f	5	* @remark Copyright 2010 ARM Ltd.
1da177e4 LT	6	* @remark Read the file COPYING
	7	*
	8	* @author Zwane Mwaikambo
8c1fc96f	9	* @author Will Deacon [move to perf]
1da177e4 LT	10	*/
1da177e4 LT	11
8c1fc96f	12	#include <linux/cpumask.h>
1da177e4	13	#include <linux/init.h>
8c1fc96f	14	#include <linux/mutex.h>
1da177e4	15	#include <linux/oprofile.h>
8c1fc96f	16	#include <linux/perf_event.h>
d1e86d64	17	#include <linux/platform_device.h>
ae92dc9f	18	#include <linux/slab.h>
8c1fc96f WD	19	#include <asm/stacktrace.h>
	20	#include <linux/uaccess.h>
	21
	22	#include <asm/perf_event.h>
	23	#include <asm/ptrace.h>
1da177e4	24
8c1fc96f	25	#ifdef CONFIG_HW_PERF_EVENTS
56946331	26	char *op_name_from_perf_id(void)
8c1fc96f	27	{
56946331 MF	28	enum arm_perf_pmu_ids id = armpmu_get_pmu_id();
56946331 MF	29
8c1fc96f WD	30	switch (id) {
	31	case ARM_PERF_PMU_ID_XSCALE1:
	32	return "arm/xscale1";
	33	case ARM_PERF_PMU_ID_XSCALE2:
	34	return "arm/xscale2";
	35	case ARM_PERF_PMU_ID_V6:
	36	return "arm/armv6";
	37	case ARM_PERF_PMU_ID_V6MP:
	38	return "arm/mpcore";
	39	case ARM_PERF_PMU_ID_CA8:
	40	return "arm/armv7";
	41	case ARM_PERF_PMU_ID_CA9:
	42	return "arm/armv7-ca9";
	43	default:
	44	return NULL;
	45	}
	46	}
d14dd7e2	47	#endif
1da177e4	48
8c1fc96f	49	static int report_trace(struct stackframe frame, void d)
1da177e4	50	{
8c1fc96f	51	unsigned int *depth = d;
c6b9dafc	52
8c1fc96f WD	53	if (*depth) {
	54	oprofile_add_trace(frame->pc);
	55	(*depth)--;
	56	}
1b7b5698	57
8c1fc96f WD	58	return *depth == 0;
8c1fc96f WD	59	}
c6b9dafc	60
8c1fc96f WD	61	/*
	62	* The registers we're interested in are at the end of the variable
	63	* length saved register structure. The fp points at the end of this
	64	* structure so the address of this struct is:
	65	* (struct frame_tail *)(xxx->fp)-1
	66	*/
	67	struct frame_tail {
	68	struct frame_tail *fp;
	69	unsigned long sp;
	70	unsigned long lr;
	71	} __attribute__((packed));
2d9e1ae0	72
8c1fc96f WD	73	static struct frame_tail* user_backtrace(struct frame_tail *tail)
	74	{
	75	struct frame_tail buftail[2];
10c03f69	76
8c1fc96f WD	77	/* Also check accessibility of one struct frame_tail beyond */
	78	if (!access_ok(VERIFY_READ, tail, sizeof(buftail)))
	79	return NULL;
	80	if (__copy_from_user_inatomic(buftail, tail, sizeof(buftail)))
	81	return NULL;
d7ac4e28	82
8c1fc96f	83	oprofile_add_trace(buftail[0].lr);
c6b9dafc	84
8c1fc96f WD	85	/* frame pointers should strictly progress back up the stack
8c1fc96f WD	86	* (towards higher addresses) */
cb06199b	87	if (tail + 1 >= buftail[0].fp)
8c1fc96f WD	88	return NULL;
	89
	90	return buftail[0].fp-1;
	91	}
	92
	93	static void arm_backtrace(struct pt_regs * const regs, unsigned int depth)
	94	{
	95	struct frame_tail tail = ((struct frame_tail ) regs->ARM_fp) - 1;
	96
	97	if (!user_mode(regs)) {
	98	struct stackframe frame;
	99	frame.fp = regs->ARM_fp;
	100	frame.sp = regs->ARM_sp;
	101	frame.lr = regs->ARM_lr;
	102	frame.pc = regs->ARM_pc;
	103	walk_stackframe(&frame, report_trace, &depth);
	104	return;
	105	}
	106
	107	while (depth-- && tail && !((unsigned long) tail & 3))
	108	tail = user_backtrace(tail);
	109	}
	110
58850e21 MF	111	int __init oprofile_arch_init(struct oprofile_operations *ops)
58850e21 MF	112	{
d14dd7e2	113	/* provide backtrace support also in timer mode: */
58850e21 MF	114	ops->backtrace = arm_backtrace;
	115
	116	return oprofile_perf_init(ops);
	117	}
	118
58850e21 MF	119	void __exit oprofile_arch_exit(void)
	120	{
	121	oprofile_perf_exit();
	122	}