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authorYang Zhang <yang.z.zhang@intel.com>2015-08-28 09:58:54 +0800
committerYang Zhang <yang.z.zhang@intel.com>2015-09-01 12:44:00 +0800
commite44e3482bdb4d0ebde2d8b41830ac2cdb07948fb (patch)
tree66b09f592c55df2878107a468a91d21506104d3f /qemu/roms/ipxe/src/arch/i386/transitions/librm_test.c
parent9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (diff)
Add qemu 2.4.0
Change-Id: Ic99cbad4b61f8b127b7dc74d04576c0bcbaaf4f5 Signed-off-by: Yang Zhang <yang.z.zhang@intel.com>
Diffstat (limited to 'qemu/roms/ipxe/src/arch/i386/transitions/librm_test.c')
-rw-r--r--qemu/roms/ipxe/src/arch/i386/transitions/librm_test.c117
1 files changed, 117 insertions, 0 deletions
diff --git a/qemu/roms/ipxe/src/arch/i386/transitions/librm_test.c b/qemu/roms/ipxe/src/arch/i386/transitions/librm_test.c
new file mode 100644
index 000000000..e07cfccdd
--- /dev/null
+++ b/qemu/roms/ipxe/src/arch/i386/transitions/librm_test.c
@@ -0,0 +1,117 @@
+/*
+ * Copyright (C) 2014 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+/** @file
+ *
+ * Real mode transition self-tests
+ *
+ * This file allows for easy measurement of the time taken to perform
+ * real mode transitions, which may have a substantial overhead when
+ * running under a hypervisor.
+ *
+ */
+
+/* Forcibly enable assertions */
+#undef NDEBUG
+
+#include <ipxe/test.h>
+#include <ipxe/profile.h>
+#include <realmode.h>
+
+/** Number of sample iterations for profiling */
+#define PROFILE_COUNT 4096
+
+/** Protected-to-real mode transition profiler */
+static struct profiler p2r_profiler __profiler = { .name = "p2r" };
+
+/** Real-to-protected mode transition profiler */
+static struct profiler r2p_profiler __profiler = { .name = "r2p" };
+
+/** Real-mode call profiler */
+static struct profiler real_call_profiler __profiler = { .name = "real_call" };
+
+/** Protected-mode call profiler */
+static struct profiler prot_call_profiler __profiler = { .name = "prot_call" };
+
+/**
+ * Dummy protected-mode function
+ */
+static void librm_test_prot_call ( void ) {
+ /* Do nothing */
+}
+
+/**
+ * Perform real mode transition self-tests
+ *
+ */
+static void librm_test_exec ( void ) {
+ unsigned int i;
+ unsigned long timestamp;
+ unsigned long started;
+ unsigned long stopped;
+ unsigned int discard_d;
+
+ /* Profile mode transitions. We want to profile each
+ * direction of the transition separately, so perform an RDTSC
+ * while in real mode and tweak the profilers' start/stop
+ * times appropriately.
+ */
+ for ( i = 0 ; i < PROFILE_COUNT ; i++ ) {
+ profile_start ( &p2r_profiler );
+ __asm__ __volatile__ ( REAL_CODE ( "rdtsc\n\t" )
+ : "=a" ( timestamp ), "=d" ( discard_d )
+ : );
+ profile_start_at ( &r2p_profiler, timestamp );
+ profile_stop ( &r2p_profiler );
+ profile_stop_at ( &p2r_profiler, timestamp );
+ }
+
+ /* Profile complete real-mode call cycle */
+ for ( i = 0 ; i < PROFILE_COUNT ; i++ ) {
+ profile_start ( &real_call_profiler );
+ __asm__ __volatile__ ( REAL_CODE ( "" ) : : );
+ profile_stop ( &real_call_profiler );
+ }
+
+ /* Profile complete protected-mode call cycle */
+ for ( i = 0 ; i < PROFILE_COUNT ; i++ ) {
+ __asm__ __volatile__ ( REAL_CODE ( "rdtsc\n\t"
+ "movl %0, %2\n\t"
+ "pushl %3\n\t"
+ "pushw %%cs\n\t"
+ "call prot_call\n\t"
+ "addw $4, %%sp\n\t"
+ "rdtsc\n\t" )
+ : "=a" ( stopped ), "=d" ( discard_d ),
+ "=r" ( started )
+ : "i" ( librm_test_prot_call ) );
+ profile_start_at ( &prot_call_profiler, started );
+ profile_stop_at ( &prot_call_profiler, stopped );
+ }
+}
+
+/** Real mode transition self-test */
+struct self_test librm_test __self_test = {
+ .name = "librm",
+ .exec = librm_test_exec,
+};
+
+REQUIRE_OBJECT ( test );