[PATCH 5/8] xen/arch: Strip out tlb-clock stubs for non-implementors

[Andrew Cooper <andrew.cooper3@xxxxxxxxxx>]

Now that there's a common stub implementation TLB clocks, there's no need for
architectures to provide their own.

Repeatedly zeroing page->tlbflush_timestamp is no use, so provide an even more
empty common stub for page_set_tlbflush_timestamp().

No practical change.

Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
---
CC: Anthony PERARD <anthony.perard@xxxxxxxxxx>
CC: Michal Orzel <michal.orzel@xxxxxxx>
CC: Jan Beulich <jbeulich@xxxxxxxx>
CC: Julien Grall <julien@xxxxxxx>
CC: Roger Pau Monné <roger.pau@xxxxxxxxxx>
CC: Stefano Stabellini <sstabellini@xxxxxxxxxx>
CC: Volodymyr Babchuk <Volodymyr_Babchuk@xxxxxxxx>
CC: Bertrand Marquis <bertrand.marquis@xxxxxxx>
CC: Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx>
CC: Shawn Anastasio <sanastasio@xxxxxxxxxxxxxxxxxxxxx>
---
 xen/arch/arm/include/asm/flushtlb.h   | 14 --------------
 xen/arch/ppc/include/asm/flushtlb.h   | 14 --------------
 xen/arch/riscv/include/asm/flushtlb.h | 14 --------------
 xen/include/xen/tlb-clock.h           |  1 +
 4 files changed, 1 insertion(+), 42 deletions(-)

diff --git a/xen/arch/arm/include/asm/flushtlb.h 
b/xen/arch/arm/include/asm/flushtlb.h
index e45fb6d97b02..6f69a5bdc8c2 100644
--- a/xen/arch/arm/include/asm/flushtlb.h
+++ b/xen/arch/arm/include/asm/flushtlb.h
@@ -3,20 +3,6 @@
 
 #include <xen/cpumask.h>
 
-/*
- * Filter the given set of CPUs, removing those that definitely flushed their
- * TLB since @page_timestamp.
- */
-/* XXX lazy implementation just doesn't clear anything.... */
-static inline void tlbflush_filter(cpumask_t *mask, uint32_t page_timestamp) {}
-
-#define tlbflush_current_time()                 (0)
-
-static inline void page_set_tlbflush_timestamp(struct page_info *page)
-{
-    page->tlbflush_timestamp = tlbflush_current_time();
-}
-
 #if defined(CONFIG_ARM_32)
 # include <asm/arm32/flushtlb.h>
 #elif defined(CONFIG_ARM_64)
diff --git a/xen/arch/ppc/include/asm/flushtlb.h 
b/xen/arch/ppc/include/asm/flushtlb.h
index afcb74078368..f89037bd4543 100644
--- a/xen/arch/ppc/include/asm/flushtlb.h
+++ b/xen/arch/ppc/include/asm/flushtlb.h
@@ -4,20 +4,6 @@
 
 #include <xen/cpumask.h>
 
-/*
- * Filter the given set of CPUs, removing those that definitely flushed their
- * TLB since @page_timestamp.
- */
-/* XXX lazy implementation just doesn't clear anything.... */
-static inline void tlbflush_filter(cpumask_t *mask, uint32_t page_timestamp) {}
-
-#define tlbflush_current_time()                 (0)
-
-static inline void page_set_tlbflush_timestamp(struct page_info *page)
-{
-    page->tlbflush_timestamp = tlbflush_current_time();
-}
-
 /* Flush specified CPUs' TLBs */
 void arch_flush_tlb_mask(const cpumask_t *mask);
 
diff --git a/xen/arch/riscv/include/asm/flushtlb.h 
b/xen/arch/riscv/include/asm/flushtlb.h
index 51c8f753c51e..23739a22fb2a 100644
--- a/xen/arch/riscv/include/asm/flushtlb.h
+++ b/xen/arch/riscv/include/asm/flushtlb.h
@@ -20,20 +20,6 @@ static inline void flush_tlb_range_va(vaddr_t va, size_t 
size)
     sbi_remote_sfence_vma(NULL, va, size);
 }
 
-/*
- * Filter the given set of CPUs, removing those that definitely flushed their
- * TLB since @page_timestamp.
- */
-/* XXX lazy implementation just doesn't clear anything.... */
-static inline void tlbflush_filter(cpumask_t *mask, uint32_t page_timestamp) {}
-
-#define tlbflush_current_time() (0)
-
-static inline void page_set_tlbflush_timestamp(struct page_info *page)
-{
-    BUG_ON("unimplemented");
-}
-
 /* Flush specified CPUs' TLBs */
 void arch_flush_tlb_mask(const cpumask_t *mask);
 
diff --git a/xen/include/xen/tlb-clock.h b/xen/include/xen/tlb-clock.h
index 796c0be7fbef..467f6d64a6ca 100644
--- a/xen/include/xen/tlb-clock.h
+++ b/xen/include/xen/tlb-clock.h
@@ -44,6 +44,7 @@ static inline void accumulate_tlbflush(
     bool *need_tlbflush, const struct page_info *page,
     uint32_t *tlbflush_timestamp) {}
 static inline void filtered_flush_tlb_mask(uint32_t tlbflush_timestamp) {}
+static inline void page_set_tlbflush_timestamp(struct page_info *page) {}
 
 #endif /* !CONFIG_HAS_TLB_CLOCK*/
 #endif /* XEN_TLB_CLOCK_H */
-- 
2.39.5