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x86/xen: remove deprecated xen_nopvspin boot parameter

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The xen_nopvspin boot parameter is deprecated since 2019. nopvspin
can be used instead.

Remove the xen_nopvspin boot parameter and replace the xen_pvspin
variable use cases with nopvspin.

This requires to move the nopvspin variable out of the .initdata
section, as it needs to be accessed for cpuhotplug, too.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Message-ID: <20240710110139.22300-1-jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
This commit is contained in:
Juergen Gross 2024-07-10 13:01:39 +02:00
parent bcea31e2d1
commit 9fe6a8c5b2
3 changed files with 6 additions and 21 deletions
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5
Documentation/admin-guide/kernel-parameters.txt
View File

@ -7439,11 +7439,6 @@
access functions when running as Xen PV guest. The access functions when running as Xen PV guest. The
default value is controlled by CONFIG_XEN_PV_MSR_SAFE. default value is controlled by CONFIG_XEN_PV_MSR_SAFE.
xen_nopvspin [X86,XEN,EARLY]
Disables the qspinlock slowpath using Xen PV optimizations.
This parameter is obsoleted by "nopvspin" parameter, which
has equivalent effect for XEN platform.
xen_nopv [X86] xen_nopv [X86]
Disables the PV optimizations forcing the HVM guest to Disables the PV optimizations forcing the HVM guest to
run as generic HVM guest with no PV drivers. run as generic HVM guest with no PV drivers.

20
arch/x86/xen/spinlock.c
View File

@ -18,7 +18,6 @@
static DEFINE_PER_CPU(int, lock_kicker_irq) = -1; static DEFINE_PER_CPU(int, lock_kicker_irq) = -1;
static DEFINE_PER_CPU(char *, irq_name); static DEFINE_PER_CPU(char *, irq_name);
static DEFINE_PER_CPU(atomic_t, xen_qlock_wait_nest); static DEFINE_PER_CPU(atomic_t, xen_qlock_wait_nest);
static bool xen_pvspin = true;
static void xen_qlock_kick(int cpu) static void xen_qlock_kick(int cpu)
{ {
@ -68,7 +67,7 @@ void xen_init_lock_cpu(int cpu)
int irq; int irq;
char *name; char *name;
if (!xen_pvspin) if (nopvspin)
return; return;
WARN(per_cpu(lock_kicker_irq, cpu) >= 0, "spinlock on CPU%d exists on IRQ%d!\n", WARN(per_cpu(lock_kicker_irq, cpu) >= 0, "spinlock on CPU%d exists on IRQ%d!\n",
@ -95,7 +94,7 @@ void xen_uninit_lock_cpu(int cpu)
{ {
int irq; int irq;
if (!xen_pvspin) if (nopvspin)
return; return;
kfree(per_cpu(irq_name, cpu)); kfree(per_cpu(irq_name, cpu));
@ -125,10 +124,10 @@ PV_CALLEE_SAVE_REGS_THUNK(xen_vcpu_stolen);
void __init xen_init_spinlocks(void) void __init xen_init_spinlocks(void)
{ {
/* Don't need to use pvqspinlock code if there is only 1 vCPU. */ /* Don't need to use pvqspinlock code if there is only 1 vCPU. */
if (num_possible_cpus() == 1 || nopvspin) if (num_possible_cpus() == 1)
xen_pvspin = false; nopvspin = true;
if (!xen_pvspin) { if (nopvspin) {
printk(KERN_DEBUG "xen: PV spinlocks disabled\n"); printk(KERN_DEBUG "xen: PV spinlocks disabled\n");
static_branch_disable(&virt_spin_lock_key); static_branch_disable(&virt_spin_lock_key);
return; return;
@ -143,12 +142,3 @@ void __init xen_init_spinlocks(void)
pv_ops.lock.kick = xen_qlock_kick; pv_ops.lock.kick = xen_qlock_kick;
pv_ops.lock.vcpu_is_preempted = PV_CALLEE_SAVE(xen_vcpu_stolen); pv_ops.lock.vcpu_is_preempted = PV_CALLEE_SAVE(xen_vcpu_stolen);
} }
static __init int xen_parse_nopvspin(char *arg)
{
pr_notice("\"xen_nopvspin\" is deprecated, please use \"nopvspin\" instead\n");
xen_pvspin = false;
return 0;
}
early_param("xen_nopvspin", xen_parse_nopvspin);

2
kernel/locking/qspinlock.c
View File

@ -583,7 +583,7 @@ EXPORT_SYMBOL(queued_spin_lock_slowpath);
#include "qspinlock_paravirt.h" #include "qspinlock_paravirt.h"
#include "qspinlock.c" #include "qspinlock.c"
bool nopvspin __initdata; bool nopvspin;
static __init int parse_nopvspin(char *arg) static __init int parse_nopvspin(char *arg)
{ {
nopvspin = true; nopvspin = true;