linux_dsm_epyc7002/arch/arm/oprofile/common.c
Matt Fleming 3d90a00763 oprofile: Abstract the perf-events backend
Move the perf-events backend from arch/arm/oprofile into
drivers/oprofile so that the code can be shared between architectures.

This allows each architecture to maintain only a single copy of the PMU
accessor functions instead of one for both perf and OProfile. It also
becomes possible for other architectures to delete much of their
OProfile code in favour of the common code now available in
drivers/oprofile/oprofile_perf.c.

Signed-off-by: Matt Fleming <matt@console-pimps.org>
Tested-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Robert Richter <robert.richter@amd.com>
2010-10-11 17:46:16 +02:00

131 lines
2.9 KiB
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/err.h>
#include <linux/errno.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;
}
}
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 >= 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)
{
ops->backtrace = arm_backtrace;
return oprofile_perf_init(ops);
}
void __exit oprofile_arch_exit(void)
{
oprofile_perf_exit();
}
#else
int __init oprofile_arch_init(struct oprofile_operations *ops)
{
pr_info("oprofile: hardware counters not available\n");
return -ENODEV;
}
void __exit oprofile_arch_exit(void) {}
#endif /* CONFIG_HW_PERF_EVENTS */