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authorIngo Molnar <mingo@kernel.org>2013-10-09 12:36:13 +0200
committerIngo Molnar <mingo@kernel.org>2013-10-09 12:36:13 +0200
commit37bf06375c90a42fe07b9bebdb07bc316ae5a0ce (patch)
treede572dd6d3955b0725001776a7b03796f99e1e8e /arch/x86/xen/spinlock.c
parent6bfa687c19b7ab8adee03f0d43c197c2945dd869 (diff)
parentd0e639c9e06d44e713170031fe05fb60ebe680af (diff)
Merge tag 'v3.12-rc4' into sched/core
Merge Linux v3.12-rc4 to fix a conflict and also to refresh the tree before applying more scheduler patches. Conflicts: arch/avr32/include/asm/Kbuild Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/xen/spinlock.c')
-rw-r--r--arch/x86/xen/spinlock.c26
1 files changed, 24 insertions, 2 deletions
diff --git a/arch/x86/xen/spinlock.c b/arch/x86/xen/spinlock.c
index 253f63fceea1..be6b86078957 100644
--- a/arch/x86/xen/spinlock.c
+++ b/arch/x86/xen/spinlock.c
@@ -259,6 +259,14 @@ void xen_uninit_lock_cpu(int cpu)
}
+/*
+ * Our init of PV spinlocks is split in two init functions due to us
+ * using paravirt patching and jump labels patching and having to do
+ * all of this before SMP code is invoked.
+ *
+ * The paravirt patching needs to be done _before_ the alternative asm code
+ * is started, otherwise we would not patch the core kernel code.
+ */
void __init xen_init_spinlocks(void)
{
@@ -267,12 +275,26 @@ void __init xen_init_spinlocks(void)
return;
}
- static_key_slow_inc(&paravirt_ticketlocks_enabled);
-
pv_lock_ops.lock_spinning = PV_CALLEE_SAVE(xen_lock_spinning);
pv_lock_ops.unlock_kick = xen_unlock_kick;
}
+/*
+ * While the jump_label init code needs to happend _after_ the jump labels are
+ * enabled and before SMP is started. Hence we use pre-SMP initcall level
+ * init. We cannot do it in xen_init_spinlocks as that is done before
+ * jump labels are activated.
+ */
+static __init int xen_init_spinlocks_jump(void)
+{
+ if (!xen_pvspin)
+ return 0;
+
+ static_key_slow_inc(&paravirt_ticketlocks_enabled);
+ return 0;
+}
+early_initcall(xen_init_spinlocks_jump);
+
static __init int xen_parse_nopvspin(char *arg)
{
xen_pvspin = false;