diff options
| author | Stephane Eranian <eranian@google.com> | 2022-03-22 23:15:12 +0100 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2022-04-05 10:24:38 +0200 |
| commit | 2a606a18cd672a16343d146a126721b34cc6adbd (patch) | |
| tree | de6c1658adb954ac20819332cf1e033fd7cb8cf2 /drivers/acpi/acpi_pad.c | |
| parent | perf/x86/amd: Make Zen3 branch sampling opt-in (diff) | |
| download | linux-2a606a18cd672a16343d146a126721b34cc6adbd.tar.xz linux-2a606a18cd672a16343d146a126721b34cc6adbd.zip | |
ACPI: Add perf low power callback
Add an optional callback needed by some PMU features, e.g., AMD
BRS, to give a chance to the perf_events code to change its state before
a CPU goes to low power and after it comes back.
The callback is void when the PERF_NEEDS_LOPWR_CB flag is not set.
This flag must be set in arch specific perf_event.h header whenever needed.
When not set, there is no impact on the ACPI code.
Signed-off-by: Stephane Eranian <eranian@google.com>
[peterz: build fix]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220322221517.2510440-9-eranian@google.com
Diffstat (limited to 'drivers/acpi/acpi_pad.c')
| -rw-r--r-- | drivers/acpi/acpi_pad.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/drivers/acpi/acpi_pad.c b/drivers/acpi/acpi_pad.c index f45979aa2d64..ec0e22a1e25d 100644 --- a/drivers/acpi/acpi_pad.c +++ b/drivers/acpi/acpi_pad.c @@ -17,6 +17,7 @@ #include <linux/tick.h> #include <linux/slab.h> #include <linux/acpi.h> +#include <linux/perf_event.h> #include <asm/mwait.h> #include <xen/xen.h> @@ -164,6 +165,9 @@ static int power_saving_thread(void *data) tsc_marked_unstable = 1; } local_irq_disable(); + + perf_lopwr_cb(true); + tick_broadcast_enable(); tick_broadcast_enter(); stop_critical_timings(); @@ -172,6 +176,9 @@ static int power_saving_thread(void *data) start_critical_timings(); tick_broadcast_exit(); + + perf_lopwr_cb(false); + local_irq_enable(); if (time_before(expire_time, jiffies)) { |