context_tracking, rcu: Rename rcu_dyntick trace event into rcu_watching

The "rcu_dyntick" naming convention has been turned into "rcu_watching" for
all helpers now, align the trace event to that.

To add to the confusion, the strings passed to the trace event are now
reversed: when RCU "starts" the dyntick / EQS state, it "stops" watching.

Signed-off-by: Valentin Schneider <vschneid@redhat.com>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Neeraj Upadhyay <neeraj.upadhyay@kernel.org>

diff --git a/include/trace/events/rcu.h b/include/trace/events/rcu.h
index 4066b6d51e46abf3d1e2fc4fc7539728ebb1a1ae..e81431deaa50b21725b08ad7c1a2992a0074065a 100644 (file)
--- a/include/trace/events/rcu.h
+++ b/include/trace/events/rcu.h
@@ -466,40 +466,40 @@ TRACE_EVENT(rcu_stall_warning,
 /*
  * Tracepoint for dyntick-idle entry/exit events.  These take 2 strings
  * as argument:
- * polarity: "Start", "End", "StillNonIdle" for entering, exiting or still not
- *            being in dyntick-idle mode.
+ * polarity: "Start", "End", "StillWatching" for entering, exiting or still not
+ *            being in EQS mode.
  * context: "USER" or "IDLE" or "IRQ".
  * NMIs nested in IRQs are inferred with nesting > 1 in IRQ context.
  *
  * These events also take a pair of numbers, which indicate the nesting
  * depth before and after the event of interest, and a third number that is
- * the ->dynticks counter.  Note that task-related and interrupt-related
+ * the RCU_WATCHING counter.  Note that task-related and interrupt-related
  * events use two separate counters, and that the "++=" and "--=" events
  * for irq/NMI will change the counter by two, otherwise by one.
  */
-TRACE_EVENT_RCU(rcu_dyntick,
+TRACE_EVENT_RCU(rcu_watching,
 
-       TP_PROTO(const char *polarity, long oldnesting, long newnesting, int dynticks),
+       TP_PROTO(const char *polarity, long oldnesting, long newnesting, int counter),
 
-       TP_ARGS(polarity, oldnesting, newnesting, dynticks),
+       TP_ARGS(polarity, oldnesting, newnesting, counter),
 
        TP_STRUCT__entry(
                __field(const char *, polarity)
                __field(long, oldnesting)
                __field(long, newnesting)
-               __field(int, dynticks)
+               __field(int, counter)
        ),
 
        TP_fast_assign(
                __entry->polarity = polarity;
                __entry->oldnesting = oldnesting;
                __entry->newnesting = newnesting;
-               __entry->dynticks = dynticks;
+               __entry->counter = counter;
        ),
 
        TP_printk("%s %lx %lx %#3x", __entry->polarity,
                  __entry->oldnesting, __entry->newnesting,
-                 __entry->dynticks & 0xfff)
+                 __entry->counter & 0xfff)
 );
 
 /*

diff --git a/kernel/context_tracking.c b/kernel/context_tracking.c
index 31c6d0c1b79df926345d62e4b7c572525b556766..938c48952d26533a1daf77bb743384a833246ef3 100644 (file)
--- a/kernel/context_tracking.c
+++ b/kernel/context_tracking.c
@@ -137,7 +137,7 @@ static void noinstr ct_kernel_exit(bool user, int offset)
 
        instrumentation_begin();
        lockdep_assert_irqs_disabled();
-       trace_rcu_dyntick(TPS("Start"), ct_nesting(), 0, ct_rcu_watching());
+       trace_rcu_watching(TPS("End"), ct_nesting(), 0, ct_rcu_watching());
        WARN_ON_ONCE(IS_ENABLED(CONFIG_RCU_EQS_DEBUG) && !user && !is_idle_task(current));
        rcu_preempt_deferred_qs(current);
 
@@ -182,7 +182,7 @@ static void noinstr ct_kernel_enter(bool user, int offset)
        // instrumentation for the noinstr ct_kernel_enter_state()
        instrument_atomic_write(&ct->state, sizeof(ct->state));
 
-       trace_rcu_dyntick(TPS("End"), ct_nesting(), 1, ct_rcu_watching());
+       trace_rcu_watching(TPS("Start"), ct_nesting(), 1, ct_rcu_watching());
        WARN_ON_ONCE(IS_ENABLED(CONFIG_RCU_EQS_DEBUG) && !user && !is_idle_task(current));
        WRITE_ONCE(ct->nesting, 1);
        WARN_ON_ONCE(ct_nmi_nesting());
@@ -219,7 +219,7 @@ void noinstr ct_nmi_exit(void)
         * leave it in non-RCU-idle state.
         */
        if (ct_nmi_nesting() != 1) {
-               trace_rcu_dyntick(TPS("--="), ct_nmi_nesting(), ct_nmi_nesting() - 2,
+               trace_rcu_watching(TPS("--="), ct_nmi_nesting(), ct_nmi_nesting() - 2,
                                  ct_rcu_watching());
                WRITE_ONCE(ct->nmi_nesting, /* No store tearing. */
                           ct_nmi_nesting() - 2);
@@ -228,7 +228,7 @@ void noinstr ct_nmi_exit(void)
        }
 
        /* This NMI interrupted an RCU-idle CPU, restore RCU-idleness. */
-       trace_rcu_dyntick(TPS("Startirq"), ct_nmi_nesting(), 0, ct_rcu_watching());
+       trace_rcu_watching(TPS("Endirq"), ct_nmi_nesting(), 0, ct_rcu_watching());
        WRITE_ONCE(ct->nmi_nesting, 0); /* Avoid store tearing. */
 
        // instrumentation for the noinstr ct_kernel_exit_state()
@@ -294,7 +294,7 @@ void noinstr ct_nmi_enter(void)
                instrumentation_begin();
        }
 
-       trace_rcu_dyntick(incby == 1 ? TPS("Endirq") : TPS("++="),
+       trace_rcu_watching(incby == 1 ? TPS("Startirq") : TPS("++="),
                          ct_nmi_nesting(),
                          ct_nmi_nesting() + incby, ct_rcu_watching());
        instrumentation_end();