rcu: Remove rsp parameter from _rcu_barrier() and friends

There now is only one rcu_state structure in a given build of the
Linux kernel, so there is no need to pass it as a parameter to RCU's
functions.  This commit therefore removes the rsp parameter from
_rcu_barrier_trace() and _rcu_barrier().

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
This commit is contained in:
Paul E. McKenney 2018-07-03 17:22:34 -07:00
parent 98ece508b5
commit 8344b871b1

View file

@ -3156,11 +3156,10 @@ static bool rcu_cpu_has_callbacks(bool *all_lazy)
* Helper function for _rcu_barrier() tracing. If tracing is disabled,
* the compiler is expected to optimize this away.
*/
static void _rcu_barrier_trace(struct rcu_state *rsp, const char *s,
int cpu, unsigned long done)
static void _rcu_barrier_trace(const char *s, int cpu, unsigned long done)
{
trace_rcu_barrier(rsp->name, s, cpu,
atomic_read(&rsp->barrier_cpu_count), done);
trace_rcu_barrier(rcu_state.name, s, cpu,
atomic_read(&rcu_state.barrier_cpu_count), done);
}
/*
@ -3173,11 +3172,10 @@ static void rcu_barrier_callback(struct rcu_head *rhp)
struct rcu_state *rsp = rdp->rsp;
if (atomic_dec_and_test(&rsp->barrier_cpu_count)) {
_rcu_barrier_trace(rsp, TPS("LastCB"), -1,
rsp->barrier_sequence);
_rcu_barrier_trace(TPS("LastCB"), -1, rsp->barrier_sequence);
complete(&rsp->barrier_completion);
} else {
_rcu_barrier_trace(rsp, TPS("CB"), -1, rsp->barrier_sequence);
_rcu_barrier_trace(TPS("CB"), -1, rsp->barrier_sequence);
}
}
@ -3189,15 +3187,14 @@ static void rcu_barrier_func(void *type)
struct rcu_state *rsp = type;
struct rcu_data *rdp = raw_cpu_ptr(&rcu_data);
_rcu_barrier_trace(rsp, TPS("IRQ"), -1, rsp->barrier_sequence);
_rcu_barrier_trace(TPS("IRQ"), -1, rsp->barrier_sequence);
rdp->barrier_head.func = rcu_barrier_callback;
debug_rcu_head_queue(&rdp->barrier_head);
if (rcu_segcblist_entrain(&rdp->cblist, &rdp->barrier_head, 0)) {
atomic_inc(&rsp->barrier_cpu_count);
} else {
debug_rcu_head_unqueue(&rdp->barrier_head);
_rcu_barrier_trace(rsp, TPS("IRQNQ"), -1,
rsp->barrier_sequence);
_rcu_barrier_trace(TPS("IRQNQ"), -1, rsp->barrier_sequence);
}
}
@ -3205,21 +3202,21 @@ static void rcu_barrier_func(void *type)
* Orchestrate the specified type of RCU barrier, waiting for all
* RCU callbacks of the specified type to complete.
*/
static void _rcu_barrier(struct rcu_state *rsp)
static void _rcu_barrier(void)
{
int cpu;
struct rcu_data *rdp;
struct rcu_state *rsp = &rcu_state;
unsigned long s = rcu_seq_snap(&rsp->barrier_sequence);
_rcu_barrier_trace(rsp, TPS("Begin"), -1, s);
_rcu_barrier_trace(TPS("Begin"), -1, s);
/* Take mutex to serialize concurrent rcu_barrier() requests. */
mutex_lock(&rsp->barrier_mutex);
/* Did someone else do our work for us? */
if (rcu_seq_done(&rsp->barrier_sequence, s)) {
_rcu_barrier_trace(rsp, TPS("EarlyExit"), -1,
rsp->barrier_sequence);
_rcu_barrier_trace(TPS("EarlyExit"), -1, rsp->barrier_sequence);
smp_mb(); /* caller's subsequent code after above check. */
mutex_unlock(&rsp->barrier_mutex);
return;
@ -3227,7 +3224,7 @@ static void _rcu_barrier(struct rcu_state *rsp)
/* Mark the start of the barrier operation. */
rcu_seq_start(&rsp->barrier_sequence);
_rcu_barrier_trace(rsp, TPS("Inc1"), -1, rsp->barrier_sequence);
_rcu_barrier_trace(TPS("Inc1"), -1, rsp->barrier_sequence);
/*
* Initialize the count to one rather than to zero in order to
@ -3250,10 +3247,10 @@ static void _rcu_barrier(struct rcu_state *rsp)
rdp = per_cpu_ptr(&rcu_data, cpu);
if (rcu_is_nocb_cpu(cpu)) {
if (!rcu_nocb_cpu_needs_barrier(rsp, cpu)) {
_rcu_barrier_trace(rsp, TPS("OfflineNoCB"), cpu,
_rcu_barrier_trace(TPS("OfflineNoCB"), cpu,
rsp->barrier_sequence);
} else {
_rcu_barrier_trace(rsp, TPS("OnlineNoCB"), cpu,
_rcu_barrier_trace(TPS("OnlineNoCB"), cpu,
rsp->barrier_sequence);
smp_mb__before_atomic();
atomic_inc(&rsp->barrier_cpu_count);
@ -3261,11 +3258,11 @@ static void _rcu_barrier(struct rcu_state *rsp)
rcu_barrier_callback, cpu, 0);
}
} else if (rcu_segcblist_n_cbs(&rdp->cblist)) {
_rcu_barrier_trace(rsp, TPS("OnlineQ"), cpu,
_rcu_barrier_trace(TPS("OnlineQ"), cpu,
rsp->barrier_sequence);
smp_call_function_single(cpu, rcu_barrier_func, rsp, 1);
} else {
_rcu_barrier_trace(rsp, TPS("OnlineNQ"), cpu,
_rcu_barrier_trace(TPS("OnlineNQ"), cpu,
rsp->barrier_sequence);
}
}
@ -3282,7 +3279,7 @@ static void _rcu_barrier(struct rcu_state *rsp)
wait_for_completion(&rsp->barrier_completion);
/* Mark the end of the barrier operation. */
_rcu_barrier_trace(rsp, TPS("Inc2"), -1, rsp->barrier_sequence);
_rcu_barrier_trace(TPS("Inc2"), -1, rsp->barrier_sequence);
rcu_seq_end(&rsp->barrier_sequence);
/* Other rcu_barrier() invocations can now safely proceed. */
@ -3294,7 +3291,7 @@ static void _rcu_barrier(struct rcu_state *rsp)
*/
void rcu_barrier_bh(void)
{
_rcu_barrier(&rcu_state);
_rcu_barrier();
}
EXPORT_SYMBOL_GPL(rcu_barrier_bh);
@ -3308,7 +3305,7 @@ EXPORT_SYMBOL_GPL(rcu_barrier_bh);
*/
void rcu_barrier(void)
{
_rcu_barrier(&rcu_state);
_rcu_barrier();
}
EXPORT_SYMBOL_GPL(rcu_barrier);