From 4e6ea1440c67de32d7c89aacf233472dfc3bce82 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Thu, 5 Feb 2009 22:30:07 -0500 Subject: [PATCH] ftrace, x86: rename in_nmi variable Impact: clean up The in_nmi variable in x86 arch ftrace.c is a misnomer. Andrew Morton pointed out that the in_nmi variable is incremented by all CPUS. It can be set when another CPU is running an NMI. Since this is actually intentional, the fix is to rename it to what it really is: "nmi_running" Signed-off-by: Steven Rostedt --- arch/x86/kernel/ftrace.c | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-) diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c index 4c683587055b..e3fad2ef622c 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 arch_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 arch_ftrace_nmi_enter(void) void arch_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++; } @@ -374,16 +374,16 @@ int ftrace_disable_ftrace_graph_caller(void) * this page for dynamic ftrace. They have been * simplified to ignore all traces in NMI context. */ -static atomic_t in_nmi; +static atomic_t nmi_running; void arch_ftrace_nmi_enter(void) { - atomic_inc(&in_nmi); + atomic_inc(&nmi_running); } void arch_ftrace_nmi_exit(void) { - atomic_dec(&in_nmi); + atomic_dec(&nmi_running); } #endif /* !CONFIG_DYNAMIC_FTRACE */ @@ -475,7 +475,7 @@ 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(atomic_read(&nmi_running))) return; if (unlikely(atomic_read(¤t->tracing_graph_pause)))