drivers: Replace __get_cpu_var with __this_cpu_read if not used for an address.
__get_cpu_var() can be replaced with this_cpu_read and will then use a single
read instruction with implied address calculation to access the correct per cpu
instance.
However, the address of a per cpu variable passed to __this_cpu_read() cannot be
determed (since its an implied address conversion through segment prefixes).
Therefore apply this only to uses of __get_cpu_var where the addres of the
variable is not used.
V3->V4:
- Move one instance of this_cpu_inc_return to a later patch
so that this one can go in without percpu infrastructrure
changes.
Sedat: fixed compile failure caused by an extra ')'.
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Sedat Dilek <sedat.dilek@gmail.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index dcb38f8..a765b82 100644
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -746,7 +746,7 @@
struct acpi_processor *pr;
struct acpi_processor_cx *cx = cpuidle_get_statedata(state);
- pr = __get_cpu_var(processors);
+ pr = __this_cpu_read(processors);
if (unlikely(!pr))
return 0;
@@ -787,7 +787,7 @@
s64 idle_time_ns;
s64 idle_time;
- pr = __get_cpu_var(processors);
+ pr = __this_cpu_read(processors);
if (unlikely(!pr))
return 0;
@@ -864,7 +864,7 @@
s64 idle_time;
- pr = __get_cpu_var(processors);
+ pr = __this_cpu_read(processors);
if (unlikely(!pr))
return 0;
diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
index a507108..978ff29 100644
--- a/drivers/cpuidle/cpuidle.c
+++ b/drivers/cpuidle/cpuidle.c
@@ -49,7 +49,7 @@
*/
static void cpuidle_idle_call(void)
{
- struct cpuidle_device *dev = __get_cpu_var(cpuidle_devices);
+ struct cpuidle_device *dev = __this_cpu_read(cpuidle_devices);
struct cpuidle_state *target_state;
int next_state;
diff --git a/drivers/s390/cio/cio.c b/drivers/s390/cio/cio.c
index f4e6cf3..430f875 100644
--- a/drivers/s390/cio/cio.c
+++ b/drivers/s390/cio/cio.c
@@ -619,7 +619,7 @@
s390_idle_check(regs, S390_lowcore.int_clock,
S390_lowcore.async_enter_timer);
irq_enter();
- __get_cpu_var(s390_idle).nohz_delay = 1;
+ __this_cpu_write(s390_idle.nohz_delay, 1);
if (S390_lowcore.int_clock >= S390_lowcore.clock_comparator)
/* Serve timer interrupts first. */
clock_comparator_work();
diff --git a/drivers/staging/speakup/fakekey.c b/drivers/staging/speakup/fakekey.c
index 65b2311..bf4ec68 100644
--- a/drivers/staging/speakup/fakekey.c
+++ b/drivers/staging/speakup/fakekey.c
@@ -78,10 +78,10 @@
/* don't change CPU */
preempt_disable();
- __get_cpu_var(reporting_keystroke) = true;
+ __this_cpu_write(reporting_keystroke, true);
input_report_key(virt_keyboard, KEY_DOWN, PRESSED);
input_report_key(virt_keyboard, KEY_DOWN, RELEASED);
- __get_cpu_var(reporting_keystroke) = false;
+ __this_cpu_write(reporting_keystroke, false);
/* reenable preemption */
preempt_enable();