@@ -418,6 +418,16 @@ static void check_init_srcu_struct(struct srcu_struct *ssp)
spin_unlock_irqrestore_rcu_node(ssp->srcu_sup, flags);
}
+/*
+ * Is the current or any upcoming grace period to be expedited?
+ */
+static bool srcu_gp_is_expedited(struct srcu_struct *ssp)
+{
+ struct srcu_usage *sup = ssp->srcu_sup;
+
+ return ULONG_CMP_LT(READ_ONCE(sup->srcu_gp_seq), READ_ONCE(sup->srcu_gp_seq_needed_exp));
+}
+
/*
* Returns approximate total of the readers' ->srcu_lock_count[] values
* for the rank of per-CPU counters specified by idx.
@@ -622,7 +632,7 @@ static unsigned long srcu_get_delay(struct srcu_struct *ssp)
unsigned long jbase = SRCU_INTERVAL;
struct srcu_usage *sup = ssp->srcu_sup;
- if (ULONG_CMP_LT(READ_ONCE(sup->srcu_gp_seq), READ_ONCE(sup->srcu_gp_seq_needed_exp)))
+ if (srcu_gp_is_expedited(ssp))
jbase = 0;
if (rcu_seq_state(READ_ONCE(sup->srcu_gp_seq))) {
j = jiffies - 1;
@@ -867,7 +877,7 @@ static void srcu_gp_end(struct srcu_struct *ssp)
spin_lock_irq_rcu_node(sup);
idx = rcu_seq_state(sup->srcu_gp_seq);
WARN_ON_ONCE(idx != SRCU_STATE_SCAN2);
- if (ULONG_CMP_LT(READ_ONCE(sup->srcu_gp_seq), READ_ONCE(sup->srcu_gp_seq_needed_exp)))
+ if (srcu_gp_is_expedited(ssp))
cbdelay = 0;
WRITE_ONCE(sup->srcu_last_gp_end, ktime_get_mono_fast_ns());
Even though the open-coded expressions usually fit on one line, this commit replaces them with a call to a new srcu_gp_is_expedited() helper function in order to improve readability. Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Andrii Nakryiko <andrii@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Kent Overstreet <kent.overstreet@linux.dev> Cc: <bpf@vger.kernel.org> --- kernel/rcu/srcutree.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-)