powerpc/rfi-flush: Differentiate enabled and patched flush types
authorMauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Sat, 26 May 2018 04:27:33 +0000 (14:27 +1000)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 30 May 2018 05:51:51 +0000 (07:51 +0200)
commit 0063d61ccfc011f379a31acaeba6de7c926fed2c upstream.

Currently the rfi-flush messages print 'Using <type> flush' for all
enabled_flush_types, but that is not necessarily true -- as now the
fallback flush is always enabled on pseries, but the fixup function
overwrites its nop/branch slot with other flush types, if available.

So, replace the 'Using <type> flush' messages with '<type> flush is
available'.

Also, print the patched flush types in the fixup function, so users
can know what is (not) being used (e.g., the slower, fallback flush,
or no flush type at all if flush is disabled via the debugfs switch).

Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arch/powerpc/kernel/setup_64.c
arch/powerpc/lib/feature-fixups.c

index ace6a10a242fe08cfa8795c9416fbec52167fecc..da12b54cbe5cf474a9ce03fad522cccf74d5ca9e 100644 (file)
@@ -860,15 +860,15 @@ static void init_fallback_flush(void)
 void setup_rfi_flush(enum l1d_flush_type types, bool enable)
 {
        if (types & L1D_FLUSH_FALLBACK) {
-               pr_info("rfi-flush: Using fallback displacement flush\n");
+               pr_info("rfi-flush: fallback displacement flush available\n");
                init_fallback_flush();
        }
 
        if (types & L1D_FLUSH_ORI)
-               pr_info("rfi-flush: Using ori type flush\n");
+               pr_info("rfi-flush: ori type flush available\n");
 
        if (types & L1D_FLUSH_MTTRIG)
-               pr_info("rfi-flush: Using mttrig type flush\n");
+               pr_info("rfi-flush: mttrig type flush available\n");
 
        enabled_flush_types = types;
 
index d0c0b8443dcfc0e6e56a347a449d65db9640193b..8ac72f7d638febb47ea074ae3594d47953004e80 100644 (file)
@@ -153,7 +153,14 @@ void do_rfi_flush_fixups(enum l1d_flush_type types)
                patch_instruction(dest + 2, instrs[2]);
        }
 
-       printk(KERN_DEBUG "rfi-flush: patched %d locations\n", i);
+       printk(KERN_DEBUG "rfi-flush: patched %d locations (%s flush)\n", i,
+               (types == L1D_FLUSH_NONE)       ? "no" :
+               (types == L1D_FLUSH_FALLBACK)   ? "fallback displacement" :
+               (types &  L1D_FLUSH_ORI)        ? (types & L1D_FLUSH_MTTRIG)
+                                                       ? "ori+mttrig type"
+                                                       : "ori type" :
+               (types &  L1D_FLUSH_MTTRIG)     ? "mttrig type"
+                                               : "unknown");
 }
 #endif /* CONFIG_PPC_BOOK3S_64 */