[PATCH RESEND] Revert "x86/paravirt: Set up the virt_spin_lock_key after static keys get initialized"

[PATCH RESEND] Revert "x86/paravirt: Set up the virt_spin_lock_key after static keys get initialized"

[Zhenzhong Duan]

This reverts commit ca5d376e17072c1b60c3fee66f3be58ef018952d.

Commit 8990cac6e5ea ("x86/jump_label: Initialize static branching
early") adds jump_label_init() call in setup_arch() to make static
keys initialized early, so we could use the original simpler code
again.

Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com>
Cc: Waiman Long <longman@redhat.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Dou Liyang <douly.fnst@cn.fujitsu.com>
---
 arch/x86/kernel/smpboot.c | 3 +--
 arch/x86/xen/spinlock.c   | 6 ++----
 2 files changed, 3 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index 362dd89..44472ca 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -1308,8 +1308,6 @@ void __init native_smp_prepare_cpus(unsigned int max_cpus)
 	pr_info("CPU0: ");
 	print_cpu_info(&cpu_data(0));
 
-	native_pv_lock_init();
-
 	uv_system_init();
 
 	set_mtrr_aps_delayed_init();
@@ -1339,6 +1337,7 @@ void __init native_smp_prepare_boot_cpu(void)
 	/* already set me in cpu_online_mask in boot_cpu_init() */
 	cpumask_set_cpu(me, cpu_callout_mask);
 	cpu_set_state_online(me);
+	native_pv_lock_init();
 }
 
 void __init calculate_max_logical_packages(void)
diff --git a/arch/x86/xen/spinlock.c b/arch/x86/xen/spinlock.c
index 3776122..6deb490 100644
--- a/arch/x86/xen/spinlock.c
+++ b/arch/x86/xen/spinlock.c
@@ -68,11 +68,8 @@ void xen_init_lock_cpu(int cpu)
 	int irq;
 	char *name;
 
-	if (!xen_pvspin) {
-		if (cpu == 0)
-			static_branch_disable(&virt_spin_lock_key);
+	if (!xen_pvspin)
 		return;
-	}
 
 	WARN(per_cpu(lock_kicker_irq, cpu) >= 0, "spinlock on CPU%d exists on IRQ%d!\n",
 	     cpu, per_cpu(lock_kicker_irq, cpu));
@@ -124,6 +121,7 @@ void __init xen_init_spinlocks(void)
 
 	if (!xen_pvspin) {
 		printk(KERN_DEBUG "xen: PV spinlocks disabled\n");
+		static_branch_disable(&virt_spin_lock_key);
 		return;
 	}
 	printk(KERN_DEBUG "xen: PV spinlocks enabled\n");
-- 
1.8.3.1

Re: [PATCH RESEND] Revert "x86/paravirt: Set up the virt_spin_lock_key after static keys get initialized"

[Thomas Gleixner]

On Wed, 26 Jun 2019, Zhenzhong Duan wrote:

> This reverts commit ca5d376e17072c1b60c3fee66f3be58ef018952d.
> 
> Commit 8990cac6e5ea ("x86/jump_label: Initialize static branching
> early") adds jump_label_init() call in setup_arch() to make static
> keys initialized early, so we could use the original simpler code
> again.
> 
> Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com>
> Cc: Waiman Long <longman@redhat.com>
> Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Cc: Ingo Molnar <mingo@redhat.com>
> Cc: Borislav Petkov <bp@alien8.de>
> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>

Boris,

want you to pick that up or should I?

In case you take it:

Reviewed-by: Thomas Gleixner <tglx@linutronix.de>

Re: [PATCH RESEND] Revert "x86/paravirt: Set up the virt_spin_lock_key after static keys get initialized"

[Boris Ostrovsky]

On Thu, Jun 27, 2019 at 11:24:41PM +0200, Thomas Gleixner wrote:
> On Wed, 26 Jun 2019, Zhenzhong Duan wrote:
> 
> > This reverts commit ca5d376e17072c1b60c3fee66f3be58ef018952d.
> > 
> > Commit 8990cac6e5ea ("x86/jump_label: Initialize static branching
> > early") adds jump_label_init() call in setup_arch() to make static
> > keys initialized early, so we could use the original simpler code
> > again.
> > 
> > Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com>
> > Cc: Waiman Long <longman@redhat.com>
> > Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
> > Cc: Thomas Gleixner <tglx@linutronix.de>
> > Cc: Ingo Molnar <mingo@redhat.com>
> > Cc: Borislav Petkov <bp@alien8.de>
> > Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
> 
> Boris,
> 
> want you to pick that up or should I?
> 
> In case you take it:
> 
> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>


We will take it via Xen tree, thanks.

-boris

Re: [PATCH RESEND] Revert "x86/paravirt: Set up the virt_spin_lock_key after static keys get initialized"

[Juergen Gross]

On 26.06.19 10:57, Zhenzhong Duan wrote:
> This reverts commit ca5d376e17072c1b60c3fee66f3be58ef018952d.
> 
> Commit 8990cac6e5ea ("x86/jump_label: Initialize static branching
> early") adds jump_label_init() call in setup_arch() to make static
> keys initialized early, so we could use the original simpler code
> again.
> 
> Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com>

Applied to xen/tip.git for-linus-5.3


Juergen