x86/mm: Be more consistent wrt PAGE_SHIFT vs PAGE_SIZE in tlb flush code

amluto · Ingo Molnar · commit be4ffc0d787f · 2017-06-05T09:59:44.000+02:00
Nadav pointed out that some code used PAGE_SIZE and other code used
PAGE_SHIFT.  Use PAGE_SHIFT instead of multiplying or dividing by
PAGE_SIZE.

Requested-by: Nadav Amit &lt;nadav.amit@gmail.com&gt;
Signed-off-by: Andy Lutomirski &lt;luto@kernel.org&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Arjan van de Ven &lt;arjan@linux.intel.com&gt;
Cc: Borislav Petkov &lt;bpetkov@suse.de&gt;
Cc: Dave Hansen &lt;dave.hansen@intel.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Mel Gorman &lt;mgorman@suse.de&gt;
Cc: Michal Hocko &lt;mhocko@suse.com&gt;
Cc: Nadav Amit &lt;nadav.amit@gmail.com&gt;
Cc: Nadav Amit &lt;namit@vmware.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Rik van Riel &lt;riel@redhat.com&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: linux-mm@kvack.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c
@@ -220,8 +220,7 @@ static void flush_tlb_func_common(const struct flush_tlb_info *f,
 		trace_tlb_flush(reason, TLB_FLUSH_ALL);
 	} else {
 		unsigned long addr;
-		unsigned long nr_pages =
-			(f->end - f->start) / PAGE_SIZE;
+		unsigned long nr_pages = (f->end - f->start) >> PAGE_SHIFT;
 		addr = f->start;
 		while (addr < f->end) {
 			__flush_tlb_single(addr);
@@ -351,7 +350,7 @@ void flush_tlb_kernel_range(unsigned long start, unsigned long end)
 
 	/* Balance as user space task's flush, a bit conservative */
 	if (end == TLB_FLUSH_ALL ||
-	    (end - start) > tlb_single_page_flush_ceiling * PAGE_SIZE) {
+	    (end - start) > tlb_single_page_flush_ceiling << PAGE_SHIFT) {
 		on_each_cpu(do_flush_tlb_all, NULL, 1);
 	} else {
 		struct flush_tlb_info info;
