File msr-tools-xen_physical_msr_support.patch of Package msr-tools

From: Jan Beulich <JBeulich@novell.com>

msr-tools: Provide access to physical msr Xen interface via parameter

Xen provides /dev/cpu/X/msr where virtual CPU msr access is emulated.
/dev/xen/cpu/X/msr is passed to the physical CPUs.
Provide access to both via -P parameter.

Signed-off-by: Thomas Renninger <trenn@suse.de>
CC: H. Peter Anvin <hpa@linux.intel.com>

---
 rdmsr.c |   11 +++++++++--
 wrmsr.c |   12 ++++++++++--
 2 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/rdmsr.c b/rdmsr.c
index 3f5e2b3..f0543b8 100644
--- a/rdmsr.c
+++ b/rdmsr.c
@@ -42,15 +42,18 @@ static const struct option long_options[] = {
 	{"zero-pad",		0, 0, '0'},
 	{"raw",			0, 0, 'r'},
 	{"all",			0, 0, 'a'},
+	{"phys-cpu",		1, 0, 'P'},
 	{"processor",		1, 0, 'p'},
 	{"cpu",			1, 0, 'p'},
 	{"bitfield",		1, 0, 'f'},
 	{0, 0, 0, 0}
 };
-static const char short_options[] = "hVxXdoruc0ap:f:";
+static const char short_options[] = "hVxXdoruc0aP:p:f:";
 
 static const char *proc_stat = "/proc/stat";
 
+static const char *msr_file_pattern = "/dev/cpu/%d/msr";
+
 /* Number of decimal digits for a certain number of bits */
 /* (int) ceil(log(2^n)/log(10)) */
 static const int decdigits[] = {
@@ -89,6 +92,7 @@ static void usage(void)
 		"  --raw          -r  Raw binary output\n"
 		"  --all          -a  all processors\n"
 		"  --processor #  -p  Select processor number (default 0)\n"
+		"  --phys-cpu #   -P  Select (Xen) physical processor = number\n"
 		"  --bitfield h:l -f  Output bits [h:l] only\n", program);
 }
 
@@ -107,7 +111,7 @@ static void rdmsr_on_cpu(const struct format *fmt, uint32_t reg, int cpu)
 	char msr_file_name[64];
 	unsigned int bits;
 
-	sprintf(msr_file_name, "/dev/cpu/%d/msr", cpu);
+	sprintf(msr_file_name, msr_file_pattern, cpu);
 	fd = open(msr_file_name, O_RDONLY);
 	if (fd < 0) {
 		if (errno == ENXIO) {
@@ -332,6 +336,9 @@ int main(int argc, char *argv[])
 		case 'a':
 			cpu = -1;
 			break;
+		case 'P':
+			msr_file_pattern = "/dev/xen/cpu/%d/msr";
+			/* fall through */
 		case 'p':
 			arg = strtoul(optarg, &endarg, 0);
 			if (*endarg || arg > 255) {
diff --git a/wrmsr.c b/wrmsr.c
index 9800841..cb4a7e4 100644
--- a/wrmsr.c
+++ b/wrmsr.c
@@ -33,12 +33,16 @@ static const struct option long_options[] = {
 	{"version",	0, 0, 'V'},
 	{"all",		0, 0, 'a'},
 	{"processor",	1, 0, 'p'},
+	{"phys-cpu",	1, 0, 'P'},
 	{"cpu",		1, 0, 'p'},
 	{0, 0, 0, 0}
 };
-static const char short_options[] = "hVap:";
+static const char short_options[] = "hVaP:p:";
 
 static const char *proc_stat = "/proc/stat";
+
+static const char *msr_file_pattern = "/dev/cpu/%d/msr";
+
 const char *program;
 
 static void usage(void)
@@ -47,6 +51,7 @@ static void usage(void)
 		"  --help         -h  Print this help\n"
 		"  --version      -V  Print current version\n"
 		"  --all          -a  all processors\n"
+		"  --phys-cpu #   -P  Select (Xen) physical processor = number\n"
 		"  --processor #  -p  Select processor number (default 0)\n",
 		program);
 }
@@ -56,7 +61,7 @@ static void wrmsr_on_cpu(uint32_t reg, uint64_t data, int cpu)
 	int fd;
 	char msr_file_name[64];
 
-	sprintf(msr_file_name, "/dev/cpu/%d/msr", cpu);
+	sprintf(msr_file_name, msr_file_pattern, cpu);
 	fd = open(msr_file_name, O_WRONLY);
 	if (fd < 0) {
 		if (errno == ENXIO) {
@@ -141,6 +146,9 @@ int main(int argc, char *argv[])
 		case 'a':
 			cpu = -1;
 			break;
+		case 'P':
+			msr_file_pattern = "/dev/xen/cpu/%d/msr";
+			/* fall through */
 		case 'p':
 			arg = strtoul(optarg, &endarg, 0);
 			if (*endarg || arg > 255) {