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Code Issues Releases Wiki Activity

Merge branch 'oprofile/urgent' into HEAD

This commit is contained in:
Robert Richter 2011-06-15 14:37:35 +02:00
parent 5f307491f3 a0e3e70243
commit a406ab6d77
2 changed files with 57 additions and 13 deletions
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56
arch/x86/oprofile/backtrace.c
View File

@ -11,10 +11,12 @@
#include <linux/oprofile.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/compat.h>
#include <linux/highmem.h>
#include <asm/ptrace.h>
#include <asm/uaccess.h>
#include <asm/stacktrace.h>
#include <linux/compat.h>
static int backtrace_stack(void *data, char *name)
{
@ -36,17 +38,53 @@ static struct stacktrace_ops backtrace_ops = {
.walk_stack = print_context_stack,
};
/* from arch/x86/kernel/cpu/perf_event.c: */
/*
* best effort, GUP based copy_from_user() that assumes IRQ or NMI context
*/
static unsigned long
copy_from_user_nmi(void *to, const void __user *from, unsigned long n)
{
unsigned long offset, addr = (unsigned long)from;
unsigned long size, len = 0;
struct page *page;
void *map;
int ret;
do {
ret = __get_user_pages_fast(addr, 1, 0, &page);
if (!ret)
break;
offset = addr & (PAGE_SIZE - 1);
size = min(PAGE_SIZE - offset, n - len);
map = kmap_atomic(page);
memcpy(to, map+offset, size);
kunmap_atomic(map);
put_page(page);
len += size;
to += size;
addr += size;
} while (len < n);
return len;
}
#ifdef CONFIG_COMPAT
static struct stack_frame_ia32 *
dump_user_backtrace_32(struct stack_frame_ia32 *head)
{
/* Also check accessibility of one struct frame_head beyond: */
struct stack_frame_ia32 bufhead[2];
struct stack_frame_ia32 *fp;
unsigned long bytes;
/* Also check accessibility of one struct frame_head beyond */
if (!access_ok(VERIFY_READ, head, sizeof(bufhead)))
return NULL;
if (__copy_from_user_inatomic(bufhead, head, sizeof(bufhead)))
bytes = copy_from_user_nmi(bufhead, head, sizeof(bufhead));
if (bytes != sizeof(bufhead))
return NULL;
fp = (struct stack_frame_ia32 *) compat_ptr(bufhead[0].next_frame);
@ -87,12 +125,12 @@ x86_backtrace_32(struct pt_regs * const regs, unsigned int depth)
static struct stack_frame *dump_user_backtrace(struct stack_frame *head)
{
/* Also check accessibility of one struct frame_head beyond: */
struct stack_frame bufhead[2];
unsigned long bytes;
/* Also check accessibility of one struct stack_frame beyond */
if (!access_ok(VERIFY_READ, head, sizeof(bufhead)))
return NULL;
if (__copy_from_user_inatomic(bufhead, head, sizeof(bufhead)))
bytes = copy_from_user_nmi(bufhead, head, sizeof(bufhead));
if (bytes != sizeof(bufhead))
return NULL;
oprofile_add_trace(bufhead[0].return_address);

14
arch/x86/oprofile/nmi_int.c
View File

@ -112,8 +112,10 @@ static void nmi_cpu_start(void *dummy)
static int nmi_start(void)
{
get_online_cpus();
on_each_cpu(nmi_cpu_start, NULL, 1);
ctr_running = 1;
/* make ctr_running visible to the nmi handler: */
smp_mb();
on_each_cpu(nmi_cpu_start, NULL, 1);
put_online_cpus();
return 0;
}
@ -504,15 +506,18 @@ static int nmi_setup(void)
nmi_enabled = 0;
ctr_running = 0;
barrier();
/* make variables visible to the nmi handler: */
smp_mb();
err = register_die_notifier(&profile_exceptions_nb);
if (err)
goto fail;
get_online_cpus();
register_cpu_notifier(&oprofile_cpu_nb);
on_each_cpu(nmi_cpu_setup, NULL, 1);
nmi_enabled = 1;
/* make nmi_enabled visible to the nmi handler: */
smp_mb();
on_each_cpu(nmi_cpu_setup, NULL, 1);
put_online_cpus();
return 0;
@ -531,7 +536,8 @@ static void nmi_shutdown(void)
nmi_enabled = 0;
ctr_running = 0;
put_online_cpus();
barrier();
/* make variables visible to the nmi handler: */
smp_mb();
unregister_die_notifier(&profile_exceptions_nb);
msrs = &get_cpu_var(cpu_msrs);
model->shutdown(msrs);