[v2,08/13] cpufreq: acpi-cpufreq: Mark 'dummy' variable as __always_unused

Message ID 20200715082634.3024816-9-lee.jones@linaro.org
State Accepted
Commit e1711f296a2de54a6dd5bde4d92bb903dfaed1fb
Headers show
Series
  • Rid W=1 warnings in CPUFreq
Related show

Commit Message

Lee Jones July 15, 2020, 8:26 a.m.
If we fail to use a variable, even a 'dummy' one, then the compiler
complains that it is set but not used.  We know this is fine, so we
set it as __always_unused to let the compiler know.

Fixes the following W=1 kernel build warning(s):

 drivers/cpufreq/acpi-cpufreq.c: In function ‘cpu_freq_read_intel’:
 drivers/cpufreq/acpi-cpufreq.c:247:11: warning: variable ‘dummy’ set but not used [-Wunused-but-set-variable]
 drivers/cpufreq/acpi-cpufreq.c: In function ‘cpu_freq_read_amd’:
 drivers/cpufreq/acpi-cpufreq.c:265:11: warning: variable ‘dummy’ set but not used [-Wunused-but-set-variable]

Cc: Andy Grover <andrew.grover@intel.com>
Cc: Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
Cc: Dominik Brodowski <linux@brodo.de>
Cc: Denis Sadykov <denis.m.sadykov@intel.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

---
 drivers/cpufreq/acpi-cpufreq.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

-- 
2.25.1

Patch

diff --git a/drivers/cpufreq/acpi-cpufreq.c b/drivers/cpufreq/acpi-cpufreq.c
index 429e5a36c08a9..6b3d8355c8dea 100644
--- a/drivers/cpufreq/acpi-cpufreq.c
+++ b/drivers/cpufreq/acpi-cpufreq.c
@@ -244,7 +244,7 @@  static unsigned extract_freq(struct cpufreq_policy *policy, u32 val)
 
 static u32 cpu_freq_read_intel(struct acpi_pct_register *not_used)
 {
-	u32 val, dummy;
+	u32 val, dummy __always_unused;
 
 	rdmsr(MSR_IA32_PERF_CTL, val, dummy);
 	return val;
@@ -261,7 +261,7 @@  static void cpu_freq_write_intel(struct acpi_pct_register *not_used, u32 val)
 
 static u32 cpu_freq_read_amd(struct acpi_pct_register *not_used)
 {
-	u32 val, dummy;
+	u32 val, dummy __always_unused;
 
 	rdmsr(MSR_AMD_PERF_CTL, val, dummy);
 	return val;