x86/mm: Clean up the TLB flushing code

The

	if (cpumask_any_but(mm_cpumask(mm), smp_processor_id()) < nr_cpu_ids)

line of code is not exactly the easiest to audit, especially when
it ends up at two different indentation levels.  This eliminates
one of the the copy-n-paste versions.  It also gives us a unified
exit point for each path through this function.  We need this in
a minute for our tracepoint.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: http://lkml.kernel.org/r/20140731154054.44F1CDDC@viggo.jf.intel.com
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

1 files changed, 11 insertions, 12 deletions

diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c
index dd8dda167a24..378fbef279d2 100644
--- a/arch/x86/mm/tlb.c
+++ b/arch/x86/mm/tlb.c
@@ -161,23 +161,24 @@ void flush_tlb_current_task(void)
 void flush_tlb_mm_range(struct mm_struct *mm, unsigned long start,
                                 unsigned long end, unsigned long vmflag)
 {
+        bool need_flush_others_all = true;
         unsigned long addr;
         unsigned act_entries, tlb_entries = 0;
         unsigned long nr_base_pages;
 
         preempt_disable();
         if (current->active_mm != mm)
-                goto flush_all;
+                goto out;
 
         if (!current->mm) {
                 leave_mm(smp_processor_id());
-                goto flush_all;
+                goto out;
         }
 
         if (end == TLB_FLUSH_ALL || tlb_flushall_shift == -1
                                         || vmflag & VM_HUGETLB) {
                 local_flush_tlb();
-                goto flush_all;
+                goto out;
         }
 
         /* In modern CPU, last level tlb used for both data/ins */
@@ -196,22 +197,20 @@ void flush_tlb_mm_range(struct mm_struct *mm, unsigned long start,
                 count_vm_tlb_event(NR_TLB_LOCAL_FLUSH_ALL);
                 local_flush_tlb();
         } else {
+                need_flush_others_all = false;
                 /* flush range by one by one 'invlpg' */
                 for (addr = start; addr < end;  addr += PAGE_SIZE) {
                         count_vm_tlb_event(NR_TLB_LOCAL_FLUSH_ONE);
                         __flush_tlb_single(addr);
                 }
-
-                if (cpumask_any_but(mm_cpumask(mm),
-                                smp_processor_id()) < nr_cpu_ids)
-                        flush_tlb_others(mm_cpumask(mm), mm, start, end);
-                preempt_enable();
-                return;
         }
-
-flush_all:
+out:
+        if (need_flush_others_all) {
+                start = 0UL;
+                end = TLB_FLUSH_ALL;
+        }
         if (cpumask_any_but(mm_cpumask(mm), smp_processor_id()) < nr_cpu_ids)
-                flush_tlb_others(mm_cpumask(mm), mm, 0UL, TLB_FLUSH_ALL);
+                flush_tlb_others(mm_cpumask(mm), mm, start, end);
         preempt_enable();
 }