[PATCH 10/21] arm64: percpu: Specialise set_my_cpu_offset() for the primary CPU

[Will Deacon]

set_my_cpu_offset() is only called from smp_prepare_boot_cpu() which
runs once on the primary CPU and before alternatives have been applied.

Rework the function so that it operates only on the boot CPU offset,
drop the unused alternative code sequence and internalise it into smp.c
alongside its only caller.

Signed-off-by: Will Deacon <will at kernel.org>
---
 arch/arm64/include/asm/percpu.h | 8 --------
 arch/arm64/kernel/smp.c         | 8 +++++++-
 2 files changed, 7 insertions(+), 9 deletions(-)

diff --git a/arch/arm64/include/asm/percpu.h b/arch/arm64/include/asm/percpu.h
index b57b2bb00967..3dc7291b16e9 100644
--- a/arch/arm64/include/asm/percpu.h
+++ b/arch/arm64/include/asm/percpu.h
@@ -12,14 +12,6 @@
 #include <asm/stack_pointer.h>
 #include <asm/sysreg.h>
 
-static inline void set_my_cpu_offset(unsigned long off)
-{
-	asm volatile(ALTERNATIVE("msr tpidr_el1, %0",
-				 "msr tpidr_el2, %0",
-				 ARM64_HAS_VIRT_HOST_EXTN)
-			:: "r" (off) : "memory");
-}
-
 static inline unsigned long __hyp_my_cpu_offset(void)
 {
 	/*
diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
index a61dc3016a11..702dee8d0db5 100644
--- a/arch/arm64/kernel/smp.c
+++ b/arch/arm64/kernel/smp.c
@@ -446,6 +446,12 @@ void __init smp_cpus_done(unsigned int max_cpus)
 	mark_linear_text_alias_ro();
 }
 
+static void __init set_boot_cpu_offset(void)
+{
+	asm volatile("msr tpidr_el1, %0"
+			:: "r" (per_cpu_offset(0)) : "memory");
+}
+
 void __init smp_prepare_boot_cpu(void)
 {
 	/*
@@ -453,7 +459,7 @@ void __init smp_prepare_boot_cpu(void)
 	 * setup_per_cpu_areas(), and CPU0's boot time per-cpu area will be
 	 * freed shortly, so we must move over to the runtime per-cpu area.
 	 */
-	set_my_cpu_offset(per_cpu_offset(smp_processor_id()));
+	set_boot_cpu_offset();
 
 	cpuinfo_store_boot_cpu();
 	setup_boot_cpu_features();
-- 
2.55.0.979.g7e5102b832-goog