arm64: restore bogomips information in /proc/cpuinfo

As previously reported, some userspace applications depend on bogomips
showed by /proc/cpuinfo. Although there is much less legacy impact on
aarch64 than arm, it does break libvirt.

This patch reverts commit 326b16db9f69 ("arm64: delay: don't bother
reporting bogomips in /proc/cpuinfo"), but with some tweak due to
context change and without the pr_info().

Fixes: 326b16db9f69 ("arm64: delay: don't bother reporting bogomips in /proc/cpuinfo")
Signed-off-by: Yang Shi <yang.shi@linaro.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: <stable@vger.kernel.org> # 3.12+
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

diff --git a/arch/arm64/kernel/cpuinfo.c b/arch/arm64/kernel/cpuinfo.c
index 706679d0a0b4227c4a7267cd85142192576d7ab3..212ae6361d8be45d6d73d197284a1ca587599342 100644 (file)
--- a/arch/arm64/kernel/cpuinfo.c
+++ b/arch/arm64/kernel/cpuinfo.c
@@ -30,6 +30,7 @@
 #include <linux/seq_file.h>
 #include <linux/sched.h>
 #include <linux/smp.h>
+#include <linux/delay.h>
 
 /*
  * In case the boot CPU is hotpluggable, we record its initial state and
@@ -112,6 +113,10 @@ static int c_show(struct seq_file *m, void *v)
                 */
                seq_printf(m, "processor\t: %d\n", i);
 
+               seq_printf(m, "BogoMIPS\t: %lu.%02lu\n",
+                          loops_per_jiffy / (500000UL/HZ),
+                          loops_per_jiffy / (5000UL/HZ) % 100);
+
                /*
                 * Dump out the common processor features in a single line.
                 * Userspace should read the hwcaps with getauxval(AT_HWCAP)