[PATCH tip/core/rcu 2/2] rcu: Remove fastpath from __rcu_process_callbacks()

From: Paul E. McKenney
Date: Tue Mar 03 2015 - 12:54:05 EST


From: Alexander Gordeev <agordeev@xxxxxxxxxx>

The standard code path accommodates a condition when no
RCU callbacks are ready to invoke. Since size of the code
is a priority for tiny RCU, remove the fast path.

Cc: "Paul E. McKenney" <paulmck@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Alexander Gordeev <agordeev@xxxxxxxxxx>
Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
---
kernel/rcu/tiny.c | 11 -----------
1 file changed, 11 deletions(-)

diff --git a/kernel/rcu/tiny.c b/kernel/rcu/tiny.c
index d4e7fe5f3baf..069742d61c68 100644
--- a/kernel/rcu/tiny.c
+++ b/kernel/rcu/tiny.c
@@ -168,17 +168,6 @@ static void __rcu_process_callbacks(struct rcu_ctrlblk *rcp)
unsigned long flags;
RCU_TRACE(int cb_count = 0);

- /* If no RCU callbacks ready to invoke, just return. */
- if (&rcp->rcucblist == rcp->donetail) {
- RCU_TRACE(trace_rcu_batch_start(rcp->name, 0, 0, -1));
- RCU_TRACE(trace_rcu_batch_end(rcp->name, 0,
- !!ACCESS_ONCE(rcp->rcucblist),
- need_resched(),
- is_idle_task(current),
- false));
- return;
- }
-
/* Move the ready-to-invoke callbacks to a local list. */
local_irq_save(flags);
RCU_TRACE(trace_rcu_batch_start(rcp->name, 0, rcp->qlen, -1));
--
1.8.1.5

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/