On Wed, May 08, 2024 at 08:38:06PM +0300, Dan Carpenter wrote:
> On Wed, May 08, 2024 at 10:32:43AM -0700, Paul E. McKenney wrote:
> >
> > Agreed, and please see below for the proposed cleanup in this case.
> >
> > Thanx, Paul
>
> Thanks! Did you see the other warning I mentioned?
>
> kernel/rcu/srcutree.c:910 srcu_gp_end()
> warn: mixing irq and irqsave
I did, but then I promptly forgot about it. Thank you for the reminder.
> Btw, I'm mostly sending you these because I know you're interested in
> these sorts of cleanups. I didn't bother sending one to aacraid people,
> for example. :P
Maintainer's choice! ;-)
How about the following?
Thanx, Paul
------------------------------------------------------------------------
commit 75a3b18f319a1f06df94cfeef81d7dd6a38cd59b
Author: Paul E. McKenney <[email protected]>
Date: Wed May 8 16:47:16 2024 -0700
srcu: Disable interrupts directly in srcu_gp_end()
Interrupts are enabled in srcu_gp_end(), so this commit switches from
spin_lock_irqsave_rcu_node() and spin_unlock_irqrestore_rcu_node()
to spin_lock_irq_rcu_node() and spin_unlock_irq_rcu_node().
Link:
https://lore.kernel.org/all/[email protected]/
Reported-by: Dan Carpenter <[email protected]>
Signed-off-by: Paul E. McKenney <[email protected]>
diff --git a/kernel/rcu/srcutree.c b/kernel/rcu/srcutree.c
index 98f79ba01b0af..9a8b7ecd2ff45 100644
--- a/kernel/rcu/srcutree.c
+++ b/kernel/rcu/srcutree.c
@@ -846,7 +846,6 @@ static void srcu_gp_end(struct srcu_struct *ssp)
bool cbs;
bool last_lvl;
int cpu;
- unsigned long flags;
unsigned long gpseq;
int idx;
unsigned long mask;
@@ -908,12 +907,12 @@ static void srcu_gp_end(struct srcu_struct *ssp)
if (!(gpseq & counter_wrap_check))
for_each_possible_cpu(cpu) {
sdp = per_cpu_ptr(ssp->sda, cpu);
- spin_lock_irqsave_rcu_node(sdp, flags);
+ spin_lock_irq_rcu_node(sdp);
if (ULONG_CMP_GE(gpseq, sdp->srcu_gp_seq_needed + 100))
sdp->srcu_gp_seq_needed = gpseq;
if (ULONG_CMP_GE(gpseq, sdp->srcu_gp_seq_needed_exp +
100))
sdp->srcu_gp_seq_needed_exp = gpseq;
- spin_unlock_irqrestore_rcu_node(sdp, flags);
+ spin_unlock_irq_rcu_node(sdp);
}
/* Callback initiation done, allow grace periods after next. */
