x86/mm: Be more consistent wrt PAGE_SHIFT vs PAGE_SIZE in tlb flush code
authorAndy Lutomirski <luto@kernel.org>
Sun, 28 May 2017 17:00:16 +0000 (10:00 -0700)
committerIngo Molnar <mingo@kernel.org>
Mon, 5 Jun 2017 07:59:44 +0000 (09:59 +0200)
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 <nadav.amit@gmail.com>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Nadav Amit <nadav.amit@gmail.com>
Cc: Nadav Amit <namit@vmware.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
arch/x86/mm/tlb.c

index 44db82013f1cd8cc6cdfdb27016edb1376cbc2ff..2a5e851f203569f7344d890c9766adc4635736b6 100644 (file)
@@ -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;