TWxSoftware/twx-linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

rcu/nocb: Remove SEGCBLIST_RCU_CORE

Browse Source 
RCU core can't be running anymore while in the middle of (de-)offloading
since this sort of transition now only applies to offline CPUs.

The SEGCBLIST_RCU_CORE state can therefore be removed.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Neeraj Upadhyay <neeraj.upadhyay@kernel.org>
This commit is contained in:
Frederic Weisbecker
2024-05-30 15:45:50 +02:00
committed by Neeraj Upadhyay
parent df7c249a0e
commit bae6076ebb
4 changed files with 4 additions and 26 deletions
Download Patch File Download Diff File Expand all files Collapse all files
include/linux/rcu_segcblist.h
+4 -5
View File
@@ -185,11 +185,10 @@ struct rcu_cblist {
* ----------------------------------------------------------------------------
*/
#define SEGCBLIST_ENABLED BIT(0)
#define SEGCBLIST_RCU_CORE BIT(1)
#define SEGCBLIST_LOCKING BIT(2)
#define SEGCBLIST_KTHREAD_CB BIT(3)
#define SEGCBLIST_KTHREAD_GP BIT(4)
#define SEGCBLIST_OFFLOADED BIT(5)
#define SEGCBLIST_LOCKING BIT(1)
#define SEGCBLIST_KTHREAD_CB BIT(2)
#define SEGCBLIST_KTHREAD_GP BIT(3)
#define SEGCBLIST_OFFLOADED BIT(4)
struct rcu_segcblist {
struct rcu_head *head;
kernel/rcu/rcu_segcblist.h
-9
View File
@@ -95,15 +95,6 @@ static inline bool rcu_segcblist_is_offloaded(struct rcu_segcblist *rsclp)
return false;
}
static inline bool rcu_segcblist_completely_offloaded(struct rcu_segcblist *rsclp)
{
if (IS_ENABLED(CONFIG_RCU_NOCB_CPU) &&
!rcu_segcblist_test_flags(rsclp, SEGCBLIST_RCU_CORE))
return true;
return false;
}
/*
* Are all segments following the specified segment of the specified
* rcu_segcblist structure empty of callbacks? (The specified
kernel/rcu/tree.c
-3
View File
@@ -79,9 +79,6 @@ static void rcu_sr_normal_gp_cleanup_work(struct work_struct *);
static DEFINE_PER_CPU_SHARED_ALIGNED(struct rcu_data, rcu_data) = {
.gpwrap = true,
#ifdef CONFIG_RCU_NOCB_CPU
.cblist.flags = SEGCBLIST_RCU_CORE,
#endif
};
static struct rcu_state rcu_state = {
.level = { &rcu_state.node[0] },
kernel/rcu/tree_nocb.h
-9
View File
@@ -1060,7 +1060,6 @@ static int rcu_nocb_rdp_deoffload(struct rcu_data *rdp)
WARN_ON_ONCE(rcu_cblist_n_cbs(&rdp->nocb_bypass));
WARN_ON_ONCE(rcu_segcblist_n_cbs(&rdp->cblist));
rcu_segcblist_set_flags(cblist, SEGCBLIST_RCU_CORE);
wake_gp = rdp_offload_toggle(rdp, false, flags);
mutex_lock(&rdp_gp->nocb_gp_kthread_mutex);
@@ -1168,13 +1167,6 @@ static int rcu_nocb_rdp_offload(struct rcu_data *rdp)
swait_event_exclusive(rdp->nocb_state_wq,
rcu_segcblist_test_flags(cblist, SEGCBLIST_KTHREAD_GP));
/*
* All kthreads are ready to work, we can finally enable nocb bypass.
*/
rcu_nocb_lock_irqsave(rdp, flags);
rcu_segcblist_clear_flags(cblist, SEGCBLIST_RCU_CORE);
rcu_nocb_unlock_irqrestore(rdp, flags);
return 0;
}
@@ -1350,7 +1342,6 @@ void __init rcu_init_nohz(void)
rcu_segcblist_init(&rdp->cblist);
rcu_segcblist_offload(&rdp->cblist, true);
rcu_segcblist_set_flags(&rdp->cblist, SEGCBLIST_KTHREAD_GP);
rcu_segcblist_clear_flags(&rdp->cblist, SEGCBLIST_RCU_CORE);
}
rcu_organize_nocb_kthreads();
}