diff mbox series

[v4,03/10] cpu/SMT: Move smt/control simple exit cases earlier

Message ID 20230705145143.40545-4-ldufour@linux.ibm.com (mailing list archive)
State Accepted
Headers show
Series Introduce SMT level and add PowerPC support | expand

Commit Message

Laurent Dufour July 5, 2023, 2:51 p.m. UTC 
From: Michael Ellerman <mpe@ellerman.id.au>

Move the simple exit cases, ie. which don't depend on the value written,
earlier in the function. That makes it clearer that regardless of the
input those states can not be transitioned out of.

That does have a user-visible effect, in that the error returned will
now always be EPERM/ENODEV for those states, regardless of the value
written. Previously writing an invalid value would return EINVAL even
when in those states.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 kernel/cpu.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)
diff mbox series

Patch

diff --git a/kernel/cpu.c b/kernel/cpu.c
index e02204c4675a..b6fe170c93e9 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -2841,6 +2841,12 @@  __store_smt_control(struct device *dev, struct device_attribute *attr,
 {
 	int ctrlval, ret;
 
+	if (cpu_smt_control == CPU_SMT_FORCE_DISABLED)
+		return -EPERM;
+
+	if (cpu_smt_control == CPU_SMT_NOT_SUPPORTED)
+		return -ENODEV;
+
 	if (sysfs_streq(buf, "on"))
 		ctrlval = CPU_SMT_ENABLED;
 	else if (sysfs_streq(buf, "off"))
@@ -2850,12 +2856,6 @@  __store_smt_control(struct device *dev, struct device_attribute *attr,
 	else
 		return -EINVAL;
 
-	if (cpu_smt_control == CPU_SMT_FORCE_DISABLED)
-		return -EPERM;
-
-	if (cpu_smt_control == CPU_SMT_NOT_SUPPORTED)
-		return -ENODEV;
-
 	ret = lock_device_hotplug_sysfs();
 	if (ret)
 		return ret;