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authorIngo Molnar <mingo@elte.hu>2009-02-09 10:35:12 +0100
committerIngo Molnar <mingo@elte.hu>2009-02-09 10:35:12 +0100
commit44b0635481437140b0e29d6023f05e805d5e7620 (patch)
treeff31986115075410d0479df307a6b9841976026c /arch/x86
parent4ad476e11f94fd3724c6e272d8220e99cd222b27 (diff)
parent57794a9d48b63e34acbe63282628c9f029603308 (diff)
Merge branch 'tip/tracing/core/devel' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace into tracing/ftrace
Conflicts: kernel/trace/trace_hw_branches.c
Diffstat (limited to 'arch/x86')
-rw-r--r--arch/x86/Kconfig1
-rw-r--r--arch/x86/kernel/ftrace.c35
2 files changed, 9 insertions, 27 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 73f7fe8fd4d..2cf7bbcaed4 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -34,6 +34,7 @@ config X86
select HAVE_FUNCTION_TRACER
select HAVE_FUNCTION_GRAPH_TRACER
select HAVE_FUNCTION_TRACE_MCOUNT_TEST
+ select HAVE_FTRACE_NMI_ENTER if DYNAMIC_FTRACE
select HAVE_KVM if ((X86_32 && !X86_VOYAGER && !X86_VISWS && !X86_NUMAQ) || X86_64)
select HAVE_ARCH_KGDB if !X86_VOYAGER
select HAVE_ARCH_TRACEHOOK
diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c
index 4d33224c055..d74d75e0952 100644
--- a/arch/x86/kernel/ftrace.c
+++ b/arch/x86/kernel/ftrace.c
@@ -82,7 +82,7 @@ static unsigned char *ftrace_call_replace(unsigned long ip, unsigned long addr)
* are the same as what exists.
*/
-static atomic_t in_nmi = ATOMIC_INIT(0);
+static atomic_t nmi_running = ATOMIC_INIT(0);
static int mod_code_status; /* holds return value of text write */
static int mod_code_write; /* set when NMI should do the write */
static void *mod_code_ip; /* holds the IP to write to */
@@ -115,8 +115,8 @@ static void ftrace_mod_code(void)
void ftrace_nmi_enter(void)
{
- atomic_inc(&in_nmi);
- /* Must have in_nmi seen before reading write flag */
+ atomic_inc(&nmi_running);
+ /* Must have nmi_running seen before reading write flag */
smp_mb();
if (mod_code_write) {
ftrace_mod_code();
@@ -126,19 +126,19 @@ void ftrace_nmi_enter(void)
void ftrace_nmi_exit(void)
{
- /* Finish all executions before clearing in_nmi */
+ /* Finish all executions before clearing nmi_running */
smp_wmb();
- atomic_dec(&in_nmi);
+ atomic_dec(&nmi_running);
}
static void wait_for_nmi(void)
{
- if (!atomic_read(&in_nmi))
+ if (!atomic_read(&nmi_running))
return;
do {
cpu_relax();
- } while(atomic_read(&in_nmi));
+ } while (atomic_read(&nmi_running));
nmi_wait_count++;
}
@@ -367,25 +367,6 @@ int ftrace_disable_ftrace_graph_caller(void)
return ftrace_mod_jmp(ip, old_offset, new_offset);
}
-#else /* CONFIG_DYNAMIC_FTRACE */
-
-/*
- * These functions are picked from those used on
- * this page for dynamic ftrace. They have been
- * simplified to ignore all traces in NMI context.
- */
-static atomic_t in_nmi;
-
-void ftrace_nmi_enter(void)
-{
- atomic_inc(&in_nmi);
-}
-
-void ftrace_nmi_exit(void)
-{
- atomic_dec(&in_nmi);
-}
-
#endif /* !CONFIG_DYNAMIC_FTRACE */
/* Add a function return address to the trace stack on thread info.*/
@@ -475,7 +456,7 @@ void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr)
&return_to_handler;
/* Nmi's are currently unsupported */
- if (unlikely(atomic_read(&in_nmi)))
+ if (unlikely(in_nmi()))
return;
if (unlikely(atomic_read(&current->tracing_graph_pause)))