x86/entry: Rename trace_hardirqs_off_prepare()

The typical pattern for trace_hardirqs_off_prepare() is:

  ENTRY
    lockdep_hardirqs_off(); // because hardware
    ... do entry magic
    instrumentation_begin();
    trace_hardirqs_off_prepare();
    ... do actual work
    trace_hardirqs_on_prepare();
    lockdep_hardirqs_on_prepare();
    instrumentation_end();
    ... do exit magic
    lockdep_hardirqs_on();

which shows that it's named wrong, rename it to
trace_hardirqs_off_finish(), as it concludes the hardirq_off transition.

Also, given that the above is the only correct order, make the traditional
all-in-one trace_hardirqs_off() follow suit.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200529213321.415774872@infradead.org

diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c
index b0b1c3c..f4d5778 100644 (file)
--- a/arch/x86/entry/common.c
+++ b/arch/x86/entry/common.c
@@ -65,7 +65,7 @@ static noinstr void enter_from_user_mode(void)
 
        instrumentation_begin();
        CT_WARN_ON(state != CONTEXT_USER);
-       trace_hardirqs_off_prepare();
+       trace_hardirqs_off_finish();
        instrumentation_end();
 }
 #else
@@ -73,7 +73,7 @@ static __always_inline void enter_from_user_mode(void)
 {
        lockdep_hardirqs_off(CALLER_ADDR0);
        instrumentation_begin();
-       trace_hardirqs_off_prepare();
+       trace_hardirqs_off_finish();
        instrumentation_end();
 }
 #endif
@@ -569,7 +569,7 @@ bool noinstr idtentry_enter_cond_rcu(struct pt_regs *regs)
                lockdep_hardirqs_off(CALLER_ADDR0);
                rcu_irq_enter();
                instrumentation_begin();
-               trace_hardirqs_off_prepare();
+               trace_hardirqs_off_finish();
                instrumentation_end();
 
                return true;

diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c
index be49926..b9cb381 100644 (file)
--- a/arch/x86/kernel/cpu/mce/core.c
+++ b/arch/x86/kernel/cpu/mce/core.c
@@ -1922,7 +1922,7 @@ static __always_inline void exc_machine_check_kernel(struct pt_regs *regs)
         * that out because it's an indirect call. Annotate it.
         */
        instrumentation_begin();
-       trace_hardirqs_off_prepare();
+       trace_hardirqs_off_finish();
        machine_check_vector(regs);
        if (regs->flags & X86_EFLAGS_IF)
                trace_hardirqs_on_prepare();

diff --git a/arch/x86/kernel/nmi.c b/arch/x86/kernel/nmi.c
index 873a8c0..3a98ff3 100644 (file)
--- a/arch/x86/kernel/nmi.c
+++ b/arch/x86/kernel/nmi.c
@@ -330,7 +330,7 @@ static noinstr void default_do_nmi(struct pt_regs *regs)
        __this_cpu_write(last_nmi_rip, regs->ip);
 
        instrumentation_begin();
-       trace_hardirqs_off_prepare();
+       trace_hardirqs_off_finish();
 
        handled = nmi_handle(NMI_LOCAL, regs);
        __this_cpu_add(nmi_stats.normal, handled);

diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index 6f887be..79af913 100644 (file)
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -634,7 +634,7 @@ DEFINE_IDTENTRY_RAW(exc_int3)
        } else {
                nmi_enter();
                instrumentation_begin();
-               trace_hardirqs_off_prepare();
+               trace_hardirqs_off_finish();
                if (!do_int3(regs))
                        die("int3", regs, 0);
                if (regs->flags & X86_EFLAGS_IF)
@@ -833,7 +833,7 @@ static __always_inline void exc_debug_kernel(struct pt_regs *regs,
 {
        nmi_enter();
        instrumentation_begin();
-       trace_hardirqs_off_prepare();
+       trace_hardirqs_off_finish();
        instrumentation_end();
 
        /*

diff --git a/include/linux/irqflags.h b/include/linux/irqflags.h
index d7f7e43..6384d28 100644 (file)
--- a/include/linux/irqflags.h
+++ b/include/linux/irqflags.h
@@ -32,7 +32,7 @@
 
 #ifdef CONFIG_TRACE_IRQFLAGS
   extern void trace_hardirqs_on_prepare(void);
-  extern void trace_hardirqs_off_prepare(void);
+  extern void trace_hardirqs_off_finish(void);
   extern void trace_hardirqs_on(void);
   extern void trace_hardirqs_off(void);
 # define lockdep_hardirq_context(p)    ((p)->hardirq_context)
@@ -101,7 +101,7 @@ do {                                                \
 
 #else
 # define trace_hardirqs_on_prepare()           do { } while (0)
-# define trace_hardirqs_off_prepare()          do { } while (0)
+# define trace_hardirqs_off_finish()           do { } while (0)
 # define trace_hardirqs_on()           do { } while (0)
 # define trace_hardirqs_off()          do { } while (0)
 # define lockdep_hardirq_context(p)    0

diff --git a/kernel/trace/trace_preemptirq.c b/kernel/trace/trace_preemptirq.c
index fb0691b..f10073e 100644 (file)
--- a/kernel/trace/trace_preemptirq.c
+++ b/kernel/trace/trace_preemptirq.c
@@ -58,7 +58,7 @@ NOKPROBE_SYMBOL(trace_hardirqs_on);
  * and lockdep uses a staged approach which splits the lockdep hardirq
  * tracking into a RCU on and a RCU off section.
  */
-void trace_hardirqs_off_prepare(void)
+void trace_hardirqs_off_finish(void)
 {
        if (!this_cpu_read(tracing_irq_cpu)) {
                this_cpu_write(tracing_irq_cpu, 1);
@@ -68,19 +68,19 @@ void trace_hardirqs_off_prepare(void)
        }
 
 }
-EXPORT_SYMBOL(trace_hardirqs_off_prepare);
-NOKPROBE_SYMBOL(trace_hardirqs_off_prepare);
+EXPORT_SYMBOL(trace_hardirqs_off_finish);
+NOKPROBE_SYMBOL(trace_hardirqs_off_finish);
 
 void trace_hardirqs_off(void)
 {
+       lockdep_hardirqs_off(CALLER_ADDR0);
+
        if (!this_cpu_read(tracing_irq_cpu)) {
                this_cpu_write(tracing_irq_cpu, 1);
                tracer_hardirqs_off(CALLER_ADDR0, CALLER_ADDR1);
                if (!in_nmi())
                        trace_irq_disable_rcuidle(CALLER_ADDR0, CALLER_ADDR1);
        }
-
-       lockdep_hardirqs_off(CALLER_ADDR0);
 }
 EXPORT_SYMBOL(trace_hardirqs_off);
 NOKPROBE_SYMBOL(trace_hardirqs_off);