On Mon, Sep 11, 2023 at 11:34 PM Waiman Long <longman@xxxxxxxxxx> wrote: > > On 9/10/23 04:29, guoren@xxxxxxxxxx wrote: > > From: Guo Ren <guoren@xxxxxxxxxxxxxxxxx> > > > > Allow cmdline to force the kernel to use queued_spinlock when > > CONFIG_RISCV_COMBO_SPINLOCKS=y. > > > > Signed-off-by: Guo Ren <guoren@xxxxxxxxxxxxxxxxx> > > Signed-off-by: Guo Ren <guoren@xxxxxxxxxx> > > --- > > Documentation/admin-guide/kernel-parameters.txt | 2 ++ > > arch/riscv/kernel/setup.c | 16 +++++++++++++++- > > 2 files changed, 17 insertions(+), 1 deletion(-) > > > > diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt > > index 7dfb540c4f6c..61cacb8dfd0e 100644 > > --- a/Documentation/admin-guide/kernel-parameters.txt > > +++ b/Documentation/admin-guide/kernel-parameters.txt > > @@ -4693,6 +4693,8 @@ > > [KNL] Number of legacy pty's. Overwrites compiled-in > > default number. > > > > + qspinlock [RISCV] Force to use qspinlock or auto-detect spinlock. > > + > > qspinlock.numa_spinlock_threshold_ns= [NUMA, PV_OPS] > > Set the time threshold in nanoseconds for the > > number of intra-node lock hand-offs before the > > diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c > > index a447cf360a18..0f084f037651 100644 > > --- a/arch/riscv/kernel/setup.c > > +++ b/arch/riscv/kernel/setup.c > > @@ -270,6 +270,15 @@ static void __init parse_dtb(void) > > } > > > > #ifdef CONFIG_RISCV_COMBO_SPINLOCKS > > +bool enable_qspinlock_key = false; > > You can use __ro_after_init qualifier for enable_qspinlock_key. BTW, > this is not a static key, just a simple flag. So what is the point of > the _key suffix? Okay, I would change it to: bool enable_qspinlock_flag __ro_after_init = false; > > Cheers, > Longman > -- Best Regards Guo Ren
