[PATCH 3/3] lib: fwts_cpu: query info from the first online CPU

[Ricardo Neri]

All calls to fwts_cpu_get_info request the info of CPU0. However, this CPU
may be offline if the Linux kernel was built with
CONFIG_BOOTPARAM_HOTPLUG_CPU0. In such a case, fwts_cpu_get_info would
return an empty (and useless) structure.

Assuming that all the CPUs yield the same information, we could use the
first online CPU to query its information. We already operate under this
assumption by always querying the CPU0 info.

Functionality to query a specific CPU is preserved but now it is possible
to use -1 to query the first available CPU.

Signed-off-by: Ricardo Neri <ricardo.neri-calderon at linux.intel.com>
---
 src/bios/mtrr/mtrr.c   |  2 +-
 src/cpu/msr/msr.c      |  2 +-
 src/cpu/nx/nx.c        |  6 +++---
 src/cpu/virt/virt.c    |  2 +-
 src/lib/src/fwts_cpu.c | 11 +++++++----
 5 files changed, 13 insertions(+), 10 deletions(-)

diff --git a/src/bios/mtrr/mtrr.c b/src/bios/mtrr/mtrr.c
index 9861fe0..18e1a29 100644
--- a/src/bios/mtrr/mtrr.c
+++ b/src/bios/mtrr/mtrr.c
@@ -457,7 +457,7 @@ static int mtrr_init(fwts_framework *fw)
 		return FWTS_ERROR;
 	}
 
-	if ((fwts_cpuinfo = fwts_cpu_get_info(0)) == NULL) {
+	if ((fwts_cpuinfo = fwts_cpu_get_info(-1)) == NULL) {
 		fwts_log_error(fw, "Cannot get CPU info");
 		return FWTS_ERROR;
 	}
diff --git a/src/cpu/msr/msr.c b/src/cpu/msr/msr.c
index db6059c..54ed5a5 100644
--- a/src/cpu/msr/msr.c
+++ b/src/cpu/msr/msr.c
@@ -33,7 +33,7 @@ static int msr_init(fwts_framework *fw)
 {
 	char *bios_vendor;
 
-	if ((cpuinfo = fwts_cpu_get_info(0)) == NULL) {
+	if ((cpuinfo = fwts_cpu_get_info(-1)) == NULL) {
 		fwts_log_error(fw, "Cannot get CPU info");
 		return FWTS_ERROR;
 	}
diff --git a/src/cpu/nx/nx.c b/src/cpu/nx/nx.c
index f5d74b3..6e183d5 100644
--- a/src/cpu/nx/nx.c
+++ b/src/cpu/nx/nx.c
@@ -29,7 +29,7 @@ static int nx_test1(fwts_framework *fw)
 {
 	fwts_cpuinfo_x86 *fwts_nx_cpuinfo;
 
-	if ((fwts_nx_cpuinfo = fwts_cpu_get_info(0)) == NULL) {
+	if ((fwts_nx_cpuinfo = fwts_cpu_get_info(-1)) == NULL) {
 		fwts_log_error(fw, "Cannot get CPU info");
 		return FWTS_ERROR;
 	}
@@ -106,7 +106,7 @@ static int nx_test2(fwts_framework *fw)
 	for (i = 0; i < n; i++) {
 		fwts_cpuinfo_x86 *fwts_nx_cpuinfo;
 
-		if ((fwts_nx_cpuinfo = fwts_cpu_get_info(0)) == NULL) {
+		if ((fwts_nx_cpuinfo = fwts_cpu_get_info(-1)) == NULL) {
 			fwts_failed(fw, LOG_LEVEL_MEDIUM, "NXCPUInfoRead", "Cannot get CPU%d info", i);
 			fwts_cpu_free_info(fwts_nx_cpuinfo);
 			return FWTS_ERROR;
@@ -155,7 +155,7 @@ static int nx_test3(fwts_framework *fw)
 		fwts_cpuinfo_x86 *fwts_nx_cpuinfo;
 		uint64_t val;
 
-		if ((fwts_nx_cpuinfo = fwts_cpu_get_info(0)) == NULL) {
+		if ((fwts_nx_cpuinfo = fwts_cpu_get_info(-1)) == NULL) {
 			fwts_log_error(fw, "Cannot get CPU info");
 			return FWTS_ERROR;
 		}
diff --git a/src/cpu/virt/virt.c b/src/cpu/virt/virt.c
index ecc84d0..24b68f4 100644
--- a/src/cpu/virt/virt.c
+++ b/src/cpu/virt/virt.c
@@ -43,7 +43,7 @@ fwts_cpuinfo_x86 *fwts_virt_cpuinfo;
 
 static int virt_init(fwts_framework *fw)
 {
-	if ((fwts_virt_cpuinfo = fwts_cpu_get_info(0)) == NULL) {
+	if ((fwts_virt_cpuinfo = fwts_cpu_get_info(-1)) == NULL) {
 		fwts_log_error(fw, "Cannot get CPU info");
 		return FWTS_ERROR;
 	}
diff --git a/src/lib/src/fwts_cpu.c b/src/lib/src/fwts_cpu.c
index 2e0834d..c0b1ec2 100644
--- a/src/lib/src/fwts_cpu.c
+++ b/src/lib/src/fwts_cpu.c
@@ -99,9 +99,10 @@ void fwts_cpu_free_info(fwts_cpuinfo_x86 *cpu)
 
 /*
  *  fwts_cpu_get_info()
- *	get CPU information for specified CPU
+ *	get CPU information for specified CPU.
+ *	Specify the CPU as -1 to query the first online CPU.
  */
-fwts_cpuinfo_x86 *fwts_cpu_get_info(const int which_cpu)
+fwts_cpuinfo_x86 *fwts_cpu_get_info(int which_cpu)
 {
 	FILE *fp;
 	char buffer[1024];
@@ -127,6 +128,8 @@ fwts_cpuinfo_x86 *fwts_cpu_get_info(const int which_cpu)
 
 		if (!strncmp(buffer, "processor", 9)) {
 			sscanf(ptr, "%d", &cpu_num);
+			if (which_cpu == -1)
+				which_cpu = cpu_num;
 			if (cpu_num > which_cpu)
 				break;
 			continue;
@@ -176,7 +179,7 @@ static int fwts_cpu_matches_vendor_id(const char *vendor_id, bool *matches)
 {
 	fwts_cpuinfo_x86 *cpu;
 
-	if ((cpu = fwts_cpu_get_info(0)) == NULL)
+	if ((cpu = fwts_cpu_get_info(-1)) == NULL)
 		return FWTS_ERROR;
 	if (cpu->vendor_id == NULL) {
 		fwts_cpu_free_info(cpu);
@@ -212,7 +215,7 @@ fwts_bool fwts_cpu_has_c1e(void)
 
 	fwts_cpuinfo_x86 *cpu;
 
-	if ((cpu = fwts_cpu_get_info(0)) == NULL)
+	if ((cpu = fwts_cpu_get_info(-1)) == NULL)
 		return FWTS_BOOL_ERROR;
 	if (cpu->flags == NULL) {
 		rc FWTS_BOOL_ERROR;
-- 
2.9.0