[PATCH tip/core/rcu 05/15] rcu: Add TPS() to event-traced strings

From: Paul E. McKenney
Date: Mon Jul 24 2017 - 17:46:19 EST


Strings used in event tracing need to be specially handled, for example,
using the TPS() macro. Without the TPS() macro, although output looks
fine from within a running kernel, extracting traces from a crash dump
produces garbage instead of strings. This commit therefore adds the TPS()
macro to some unadorned strings that were passed to event-tracing macros.

Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
---
kernel/rcu/tree_plugin.h | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index bb9e6e43130f..14ba496a13cd 100644
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -2073,7 +2073,7 @@ static void nocb_leader_wait(struct rcu_data *my_rdp)

/* Wait for callbacks to appear. */
if (!rcu_nocb_poll) {
- trace_rcu_nocb_wake(my_rdp->rsp->name, my_rdp->cpu, "Sleep");
+ trace_rcu_nocb_wake(my_rdp->rsp->name, my_rdp->cpu, TPS("Sleep"));
swait_event_interruptible(my_rdp->nocb_wq,
!READ_ONCE(my_rdp->nocb_leader_sleep));
raw_spin_lock_irqsave(&my_rdp->nocb_lock, flags);
@@ -2083,7 +2083,7 @@ static void nocb_leader_wait(struct rcu_data *my_rdp)
raw_spin_unlock_irqrestore(&my_rdp->nocb_lock, flags);
} else if (firsttime) {
firsttime = false; /* Don't drown trace log with "Poll"! */
- trace_rcu_nocb_wake(my_rdp->rsp->name, my_rdp->cpu, "Poll");
+ trace_rcu_nocb_wake(my_rdp->rsp->name, my_rdp->cpu, TPS("Poll"));
}

/*
@@ -2111,7 +2111,7 @@ static void nocb_leader_wait(struct rcu_data *my_rdp)
schedule_timeout_interruptible(1);
} else {
trace_rcu_nocb_wake(my_rdp->rsp->name, my_rdp->cpu,
- "WokeEmpty");
+ TPS("WokeEmpty"));
}
goto wait_again;
}
@@ -2155,7 +2155,7 @@ static void nocb_leader_wait(struct rcu_data *my_rdp)
static void nocb_follower_wait(struct rcu_data *rdp)
{
for (;;) {
- trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu, "FollowerSleep");
+ trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu, TPS("FollowerSleep"));
swait_event_interruptible(rdp->nocb_wq,
READ_ONCE(rdp->nocb_follower_head));
if (smp_load_acquire(&rdp->nocb_follower_head)) {
@@ -2163,7 +2163,7 @@ static void nocb_follower_wait(struct rcu_data *rdp)
return;
}
WARN_ON(signal_pending(current));
- trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu, "WokeEmpty");
+ trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu, TPS("WokeEmpty"));
}
}

@@ -2198,7 +2198,7 @@ static int rcu_nocb_kthread(void *arg)
rdp->nocb_follower_tail = &rdp->nocb_follower_head;
raw_spin_unlock_irqrestore(&rdp->nocb_lock, flags);
BUG_ON(!list);
- trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu, "WokeNonEmpty");
+ trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu, TPS("WokeNonEmpty"));

/* Each pass through the following loop invokes a callback. */
trace_rcu_batch_start(rdp->rsp->name,
--
2.5.2