x86/mm/cpa: Move CLFLUSH test into cpa_flush_array()
authorPeter Zijlstra <peterz@infradead.org>
Wed, 19 Sep 2018 08:50:22 +0000 (10:50 +0200)
committerThomas Gleixner <tglx@linutronix.de>
Thu, 27 Sep 2018 18:39:42 +0000 (20:39 +0200)
Rather than guarding cpa_flush_array() users with a CLFLUSH test, put
it inside.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Dave Hansen <dave.hansen@intel.com>
Cc: Bin Yang <bin.yang@intel.com>
Cc: Mark Gross <mark.gross@intel.com>
Link: https://lkml.kernel.org/r/20180919085948.087848187@infradead.org
arch/x86/mm/pageattr.c

index 3cc4a2ae4dbb15bf91f119f2fee0ecf74d8714fd..33d89d505f9356df74486a56548d1cbca623f242 100644 (file)
@@ -328,6 +328,11 @@ static void cpa_flush_array(unsigned long baddr, unsigned long *start,
 
        BUG_ON(irqs_disabled() && !early_boot_irqs_disabled);
 
+       if (!static_cpu_has(X86_FEATURE_CLFLUSH)) {
+               cpa_flush_all(cache);
+               return;
+       }
+
        flush_tlb_kernel_range(baddr, baddr + PAGE_SIZE * numpages);
 
        if (!cache)
@@ -1756,19 +1761,19 @@ static int change_page_attr_set_clr(unsigned long *addr, int numpages,
        cache = !!pgprot2cachemode(mask_set);
 
        /*
-        * On success we use CLFLUSH, when the CPU supports it to
-        * avoid the WBINVD. If the CPU does not support it and in the
-        * error case we fall back to cpa_flush_all (which uses
-        * WBINVD):
+        * On error; flush everything to be sure.
         */
-       if (!ret && boot_cpu_has(X86_FEATURE_CLFLUSH)) {
-               if (cpa.flags & (CPA_PAGES_ARRAY | CPA_ARRAY)) {
-                       cpa_flush_array(baddr, addr, numpages, cache,
-                                       cpa.flags, pages);
-               } else
-                       cpa_flush_range(baddr, numpages, cache);
-       } else
+       if (ret) {
                cpa_flush_all(cache);
+               goto out;
+       }
+
+       if (cpa.flags & (CPA_PAGES_ARRAY | CPA_ARRAY)) {
+               cpa_flush_array(baddr, addr, numpages, cache,
+                               cpa.flags, pages);
+       } else {
+               cpa_flush_range(baddr, numpages, cache);
+       }
 
 out:
        return ret;