s390/cpufeature: Convert MACHINE_HAS_TOPOLOGY to cpu_has_topology()

Convert MACHINE_HAS_... to cpu_has_...() which uses test_facility() instead
of testing the machine_flags lowcore member if the feature is present.

test_facility() generates better code since it results in a static branch
without accessing memory. The branch is patched via alternatives by the
decompressor depending on the availability of the required facility.

Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

6 files changed, 18 insertions, 16 deletions

diff --git a/arch/s390/include/asm/cpufeature.h b/arch/s390/include/asm/cpufeature.h
index 6ba487a7c842..5c7c535a3b5b 100644
--- a/arch/s390/include/asm/cpufeature.h
+++ b/arch/s390/include/asm/cpufeature.h
@@ -27,5 +27,6 @@ int cpu_have_feature(unsigned int nr);
 #define cpu_has_rdp()		test_facility(194)
 #define cpu_has_seq_insn()	test_facility(85)
 #define cpu_has_tlb_lc()	test_facility(51)
+#define cpu_has_topology()	test_facility(11)
 
 #endif /* __ASM_S390_CPUFEATURE_H */
diff --git a/arch/s390/include/asm/setup.h b/arch/s390/include/asm/setup.h
index b117f3a4b4c2..25f4d5b6e23b 100644
--- a/arch/s390/include/asm/setup.h
+++ b/arch/s390/include/asm/setup.h
@@ -25,7 +25,6 @@
 #define MACHINE_FLAG_IDTE	BIT(5)
 #define MACHINE_FLAG_EDAT1	BIT(7)
 #define MACHINE_FLAG_EDAT2	BIT(8)
-#define MACHINE_FLAG_TOPOLOGY	BIT(10)
 #define MACHINE_FLAG_TE		BIT(11)
 #define MACHINE_FLAG_TLB_GUEST	BIT(14)
 #define MACHINE_FLAG_SCC	BIT(17)
@@ -82,7 +81,6 @@ extern unsigned long mio_wb_bit_mask;
 #define MACHINE_HAS_IDTE	(get_lowcore()->machine_flags & MACHINE_FLAG_IDTE)
 #define MACHINE_HAS_EDAT1	(get_lowcore()->machine_flags & MACHINE_FLAG_EDAT1)
 #define MACHINE_HAS_EDAT2	(get_lowcore()->machine_flags & MACHINE_FLAG_EDAT2)
-#define MACHINE_HAS_TOPOLOGY	(get_lowcore()->machine_flags & MACHINE_FLAG_TOPOLOGY)
 #define MACHINE_HAS_TE		(get_lowcore()->machine_flags & MACHINE_FLAG_TE)
 #define MACHINE_HAS_TLB_GUEST	(get_lowcore()->machine_flags & MACHINE_FLAG_TLB_GUEST)
 #define MACHINE_HAS_SCC		(get_lowcore()->machine_flags & MACHINE_FLAG_SCC)
diff --git a/arch/s390/kernel/early.c b/arch/s390/kernel/early.c
index 1f22dd8094ec..68685aa23c16 100644
--- a/arch/s390/kernel/early.c
+++ b/arch/s390/kernel/early.c
@@ -8,6 +8,7 @@
 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
 
 #include <linux/sched/debug.h>
+#include <linux/cpufeature.h>
 #include <linux/compiler.h>
 #include <linux/init.h>
 #include <linux/errno.h>
@@ -167,9 +168,8 @@ static __init void setup_topology(void)
 {
 	int max_mnest;
 
-	if (!test_facility(11))
+	if (!cpu_has_topology())
 		return;
-	get_lowcore()->machine_flags |= MACHINE_FLAG_TOPOLOGY;
 	for (max_mnest = 6; max_mnest > 1; max_mnest--) {
 		if (stsi(&sysinfo_page, 15, 1, max_mnest) == 0)
 			break;
diff --git a/arch/s390/kernel/hiperdispatch.c b/arch/s390/kernel/hiperdispatch.c
index 7857a7e8e56c..e7b66d046e8d 100644
--- a/arch/s390/kernel/hiperdispatch.c
+++ b/arch/s390/kernel/hiperdispatch.c
@@ -45,6 +45,7 @@
  * therefore delaying the throughput loss caused by using SMP threads.
  */
 
+#include <linux/cpufeature.h>
 #include <linux/cpumask.h>
 #include <linux/debugfs.h>
 #include <linux/device.h>
@@ -87,7 +88,7 @@ static DECLARE_DELAYED_WORK(hd_capacity_work, hd_capacity_work_fn);
 
 static int hd_set_hiperdispatch_mode(int enable)
 {
-	if (!MACHINE_HAS_TOPOLOGY)
+	if (!cpu_has_topology())
 		enable = 0;
 	if (hd_enabled == enable)
 		return 0;
diff --git a/arch/s390/kernel/sysinfo.c b/arch/s390/kernel/sysinfo.c
index 88055f58fbda..a74154c6529e 100644
--- a/arch/s390/kernel/sysinfo.c
+++ b/arch/s390/kernel/sysinfo.c
@@ -5,6 +5,7 @@
  *	       Martin Schwidefsky <schwidefsky@de.ibm.com>,
  */
 
+#include <linux/cpufeature.h>
 #include <linux/debugfs.h>
 #include <linux/kernel.h>
 #include <linux/mm.h>
@@ -154,7 +155,7 @@ static void stsi_15_1_x(struct seq_file *m, struct sysinfo_15_1_x *info)
 	int i;
 
 	seq_putc(m, '\n');
-	if (!MACHINE_HAS_TOPOLOGY)
+	if (!cpu_has_topology())
 		return;
 	if (stsi(info, 15, 1, topology_max_mnest))
 		return;
@@ -559,7 +560,7 @@ static __init int stsi_init_debugfs(void)
 		sf = &stsi_file[i];
 		debugfs_create_file(sf->name, 0400, stsi_root, NULL, sf->fops);
 	}
-	if (IS_ENABLED(CONFIG_SCHED_TOPOLOGY) && MACHINE_HAS_TOPOLOGY) {
+	if (IS_ENABLED(CONFIG_SCHED_TOPOLOGY) && cpu_has_topology()) {
 		char link_to[10];
 
 		sprintf(link_to, "15_1_%d", topology_mnest_limit());
diff --git a/arch/s390/kernel/topology.c b/arch/s390/kernel/topology.c
index 211cc8382e4a..3df048e190b1 100644
--- a/arch/s390/kernel/topology.c
+++ b/arch/s390/kernel/topology.c
@@ -6,6 +6,7 @@
 #define KMSG_COMPONENT "cpu"
 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
 
+#include <linux/cpufeature.h>
 #include <linux/workqueue.h>
 #include <linux/memblock.h>
 #include <linux/uaccess.h>
@@ -240,7 +241,7 @@ int topology_set_cpu_management(int fc)
 {
 	int cpu, rc;
 
-	if (!MACHINE_HAS_TOPOLOGY)
+	if (!cpu_has_topology())
 		return -EOPNOTSUPP;
 	if (fc)
 		rc = ptf(PTF_VERTICAL);
@@ -315,13 +316,13 @@ static int __arch_update_cpu_topology(void)
 	hd_status = 0;
 	rc = 0;
 	mutex_lock(&smp_cpu_state_mutex);
-	if (MACHINE_HAS_TOPOLOGY) {
+	if (cpu_has_topology()) {
 		rc = 1;
 		store_topology(info);
 		tl_to_masks(info);
 	}
 	update_cpu_masks();
-	if (!MACHINE_HAS_TOPOLOGY)
+	if (!cpu_has_topology())
 		topology_update_polarization_simple();
 	if (cpu_management == 1)
 		hd_status = hd_enable_hiperdispatch();
@@ -376,7 +377,7 @@ static void set_topology_timer(void)
 
 void topology_expect_change(void)
 {
-	if (!MACHINE_HAS_TOPOLOGY)
+	if (!cpu_has_topology())
 		return;
 	/* This is racy, but it doesn't matter since it is just a heuristic.
 	 * Worst case is that we poll in a higher frequency for a bit longer.
@@ -500,7 +501,7 @@ int topology_cpu_init(struct cpu *cpu)
 	int rc;
 
 	rc = sysfs_create_group(&cpu->dev.kobj, &topology_cpu_attr_group);
-	if (rc || !MACHINE_HAS_TOPOLOGY)
+	if (rc || !cpu_has_topology())
 		return rc;
 	rc = sysfs_create_group(&cpu->dev.kobj, &topology_extra_cpu_attr_group);
 	if (rc)
@@ -569,12 +570,12 @@ void __init topology_init_early(void)
 
 	set_sched_topology(s390_topology);
 	if (topology_mode == TOPOLOGY_MODE_UNINITIALIZED) {
-		if (MACHINE_HAS_TOPOLOGY)
+		if (cpu_has_topology())
 			topology_mode = TOPOLOGY_MODE_HW;
 		else
 			topology_mode = TOPOLOGY_MODE_SINGLE;
 	}
-	if (!MACHINE_HAS_TOPOLOGY)
+	if (!cpu_has_topology())
 		goto out;
 	tl_info = memblock_alloc_or_panic(PAGE_SIZE, PAGE_SIZE);
 	info = tl_info;
@@ -596,7 +597,7 @@ static inline int topology_get_mode(int enabled)
 {
 	if (!enabled)
 		return TOPOLOGY_MODE_SINGLE;
-	return MACHINE_HAS_TOPOLOGY ? TOPOLOGY_MODE_HW : TOPOLOGY_MODE_PACKAGE;
+	return cpu_has_topology() ? TOPOLOGY_MODE_HW : TOPOLOGY_MODE_PACKAGE;
 }
 
 static inline int topology_is_enabled(void)
@@ -686,7 +687,7 @@ static int __init topology_init(void)
 	int rc = 0;
 
 	timer_setup(&topology_timer, topology_timer_fn, TIMER_DEFERRABLE);
-	if (MACHINE_HAS_TOPOLOGY)
+	if (cpu_has_topology())
 		set_topology_timer();
 	else
 		topology_update_polarization_simple();