From 80943aa40e30bcba24f52eff156c29d9d57a2e53 Mon Sep 17 00:00:00 2001
From: Dongli Zhang <dongli.zhang@oracle.com>
Date: Tue, 20 Sep 2016 16:13:51 +0200
Subject: [PATCH] replace tlbflush check and operation with inline functions

This patch cleaned up the code by replacing complicated tlbflush check and
operation with inline functions. We should use those inline functions to
avoid the complicated tlbflush check and tlbflush operations when
implementing TODOs left in commit a902c12ee45fc9389eb8fe54eeddaf267a555c58
(More efficient TLB-flush filtering in alloc_heap_pages()).

"#include <asm/flushtlb.h>" is removed from xen/arch/x86/acpi/suspend.c to
avoid the compiling error after we include "<asm/flushtlb.h>" to
xen/include/xen/mm.h.

Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Acked-by: George Dunlap <george.dunlap@citrix.com>
Reviewed-by: Dario Faggioli <dario.faggioli@citrix.com>
---
 xen/arch/x86/acpi/suspend.c |  1 -
 xen/common/page_alloc.c     | 19 ++-----------------
 xen/include/xen/mm.h        | 29 +++++++++++++++++++++++++++++
 3 files changed, 31 insertions(+), 18 deletions(-)

diff --git a/xen/arch/x86/acpi/suspend.c b/xen/arch/x86/acpi/suspend.c
index 1d8344cb35..d5c67ee1f3 100644
--- a/xen/arch/x86/acpi/suspend.c
+++ b/xen/arch/x86/acpi/suspend.c
@@ -10,7 +10,6 @@
 #include <asm/processor.h>
 #include <asm/msr.h>
 #include <asm/debugreg.h>
-#include <asm/flushtlb.h>
 #include <asm/hvm/hvm.h>
 #include <asm/hvm/support.h>
 #include <asm/i387.h>
diff --git a/xen/common/page_alloc.c b/xen/common/page_alloc.c
index 18ff6cfb40..d7ca3a0a8f 100644
--- a/xen/common/page_alloc.c
+++ b/xen/common/page_alloc.c
@@ -827,14 +827,7 @@ static struct page_info *alloc_heap_pages(
         BUG_ON(pg[i].count_info != PGC_state_free);
         pg[i].count_info = PGC_state_inuse;
 
-        if ( pg[i].u.free.need_tlbflush &&
-             (pg[i].tlbflush_timestamp <= tlbflush_current_time()) &&
-             (!need_tlbflush ||
-              (pg[i].tlbflush_timestamp > tlbflush_timestamp)) )
-        {
-            need_tlbflush = 1;
-            tlbflush_timestamp = pg[i].tlbflush_timestamp;
-        }
+        accumulate_tlbflush(&need_tlbflush, &pg[i], &tlbflush_timestamp);
 
         /* Initialise fields which have other uses for free pages. */
         pg[i].u.inuse.type_info = 0;
@@ -849,15 +842,7 @@ static struct page_info *alloc_heap_pages(
     spin_unlock(&heap_lock);
 
     if ( need_tlbflush )
-    {
-        cpumask_t mask = cpu_online_map;
-        tlbflush_filter(mask, tlbflush_timestamp);
-        if ( !cpumask_empty(&mask) )
-        {
-            perfc_incr(need_flush_tlb_flush);
-            flush_tlb_mask(&mask);
-        }
-    }
+        filtered_flush_tlb_mask(tlbflush_timestamp);
 
     return pg;
 }
diff --git a/xen/include/xen/mm.h b/xen/include/xen/mm.h
index f470e495f3..50db01de80 100644
--- a/xen/include/xen/mm.h
+++ b/xen/include/xen/mm.h
@@ -51,6 +51,7 @@
 #include <xen/spinlock.h>
 #include <xen/typesafe.h>
 #include <xen/kernel.h>
+#include <xen/perfc.h>
 #include <public/memory.h>
 
 TYPE_SAFE(unsigned long, mfn);
@@ -567,4 +568,32 @@ int prepare_ring_for_helper(struct domain *d, unsigned long gmfn,
                             struct page_info **_page, void **_va);
 void destroy_ring_for_helper(void **_va, struct page_info *page);
 
+#include <asm/flushtlb.h>
+
+static inline void accumulate_tlbflush(bool *need_tlbflush,
+                                       const struct page_info *page,
+                                       uint32_t *tlbflush_timestamp)
+{
+    if ( page->u.free.need_tlbflush &&
+         page->tlbflush_timestamp <= tlbflush_current_time() &&
+         (!*need_tlbflush ||
+          page->tlbflush_timestamp > *tlbflush_timestamp) )
+    {
+        *need_tlbflush = true;
+        *tlbflush_timestamp = page->tlbflush_timestamp;
+    }
+}
+
+static inline void filtered_flush_tlb_mask(uint32_t tlbflush_timestamp)
+{
+    cpumask_t mask = cpu_online_map;
+
+    tlbflush_filter(mask, tlbflush_timestamp);
+    if ( !cpumask_empty(&mask) )
+    {
+        perfc_incr(need_flush_tlb_flush);
+        flush_tlb_mask(&mask);
+    }
+}
+
 #endif /* __XEN_MM_H__ */
-- 
2.30.2