[PATCH 00/10] rcu/x86: Use per-cpu rcu preempt count

From: Lai Jiangshan
Date: Thu Mar 28 2024 - 03:50:59 EST


From: Lai Jiangshan <jiangshan.ljs@xxxxxxxxxxxx>

X86 can access percpu data in a single instruction.

Use per-cpu rcu preempt count and make it able to be inlined.

patch 1-7: prepare
patch 8-10: implement PCPU_RCU_PREEMPT_COUNT

Cc: "Paul E. McKenney" <paulmck@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Frederic Weisbecker <frederic@xxxxxxxxxx>

Lai Jiangshan (10):
lib: Use rcu_preempt_depth() to replace current->rcu_read_lock_nesting
rcu: Move rcu_preempt_depth_set() to rcupdate.h
rcu: Reorder tree_exp.h after tree_plugin.h
rcu: Add macros set_rcu_preempt_special() and
clear_rcu_preempt_special()
rcu: Make rcu_read_unlock_special() global
rcu: Rename marco __LINUX_RCU_H to __KERNEL_RCU_H
sched/core: Add rcu_preempt_switch()
rcu: Implement PCPU_RCU_PREEMPT_COUNT framework
x86/rcu: Add rcu_preempt_count
x86/rcu: Add THUNK rcu_read_unlock_special_thunk

arch/x86/Kconfig | 1 +
arch/x86/entry/thunk_64.S | 5 ++
arch/x86/include/asm/current.h | 3 +
arch/x86/include/asm/rcu_preempt.h | 109 +++++++++++++++++++++++++++++
arch/x86/kernel/cpu/common.c | 7 +-
include/linux/rcupdate.h | 36 ++++++++++
kernel/rcu/Kconfig | 8 +++
kernel/rcu/rcu.h | 15 +++-
kernel/rcu/tree.c | 2 +-
kernel/rcu/tree_exp.h | 2 +-
kernel/rcu/tree_plugin.h | 41 +++++++----
kernel/sched/core.c | 2 +
lib/locking-selftest.c | 6 +-
13 files changed, 211 insertions(+), 26 deletions(-)
create mode 100644 arch/x86/include/asm/rcu_preempt.h

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2.19.1.6.gb485710b