linux/arch/sh/kernel/perf_callchain.c
Frederic Weisbecker c1a65932fd perf: Drop unappropriate tests on arch callchains
Drop the TASK_RUNNING test on user tasks for callchains as
this check doesn't seem to make any sense.

Also remove the tests for !current that is not supposed to
happen and current->pid as this should be handled at the
generic level, with exclude_idle attribute.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Tested-by: Will Deacon <will.deacon@arm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: David Miller <davem@davemloft.net>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Borislav Petkov <bp@amd64.org>
2010-08-19 01:29:35 +02:00

93 lines
2.0 KiB
C

/*
* Performance event callchain support - SuperH architecture code
*
* Copyright (C) 2009 Paul Mundt
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/perf_event.h>
#include <linux/percpu.h>
#include <asm/unwinder.h>
#include <asm/ptrace.h>
static inline void callchain_store(struct perf_callchain_entry *entry, u64 ip)
{
if (entry->nr < PERF_MAX_STACK_DEPTH)
entry->ip[entry->nr++] = ip;
}
static void callchain_warning(void *data, char *msg)
{
}
static void
callchain_warning_symbol(void *data, char *msg, unsigned long symbol)
{
}
static int callchain_stack(void *data, char *name)
{
return 0;
}
static void callchain_address(void *data, unsigned long addr, int reliable)
{
struct perf_callchain_entry *entry = data;
if (reliable)
callchain_store(entry, addr);
}
static const struct stacktrace_ops callchain_ops = {
.warning = callchain_warning,
.warning_symbol = callchain_warning_symbol,
.stack = callchain_stack,
.address = callchain_address,
};
static void
perf_callchain_kernel(struct pt_regs *regs, struct perf_callchain_entry *entry)
{
callchain_store(entry, PERF_CONTEXT_KERNEL);
callchain_store(entry, regs->pc);
unwind_stack(NULL, regs, NULL, &callchain_ops, entry);
}
static void
perf_do_callchain(struct pt_regs *regs, struct perf_callchain_entry *entry)
{
int is_user;
if (!regs)
return;
is_user = user_mode(regs);
/*
* Only the kernel side is implemented for now.
*/
if (!is_user)
perf_callchain_kernel(regs, entry);
}
/*
* No need for separate IRQ and NMI entries.
*/
static DEFINE_PER_CPU(struct perf_callchain_entry, callchain);
struct perf_callchain_entry *perf_callchain(struct pt_regs *regs)
{
struct perf_callchain_entry *entry = &__get_cpu_var(callchain);
entry->nr = 0;
perf_do_callchain(regs, entry);
return entry;
}