Hi, Paul
These two patches use the special feture of the UP system:
In UP, quiescent state == grace period.
For rcu_bh, rcu_process_callbacks() == a bh == QS == GP
so we can pass rcu_bh-QS and advance GP(and callbacks) in
rcu_process_callbacks(). After doing so, rcu_bh_qs() is useless
since its work is handled by rcu_process_callbacks().
For rcu_sched, context-switch = QS = GP, thus we can force a
context-switch when call_rcu_sched() is happened on idle_task.
After doing so, rcu_idle/irq_enter/exit() are useless.
These patches remove the useless code to simplify the tiny_rcu.
We can change rcu_bh_qs() rcu_idle/irq_enter/exit() to static-inline-functions
to reduce the binary size after these two patches accepted.
Thanks,
Lai
Cc: Josh Triplett <j...@joshtriplett.org>
Cc: Steven Rostedt <rost...@goodmis.org>
Cc: Mathieu Desnoyers <mathieu.desnoy...@efficios.com>
Lai Jiangshan (2):
record rcu_bh quiescent state in RCU_SOFTIRQ
tiny_rcu: resched when call_rcu() on idle_task
kernel/rcu/rcu.h | 6 ++
kernel/rcu/tiny.c | 134 ++++++++--------------------------------------
kernel/rcu/tiny_plugin.h | 2 +-
kernel/rcu/tree.c | 6 --
4 files changed, 29 insertions(+), 119 deletions(-)
--
1.7.4.4
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
