[RFC PATCH 3/3] coresight: Support exclude_guest with Feat_TRF and nVHE

From: James Clark
Date: Fri Aug 04 2023 - 06:14:59 EST


With nVHE the filters need to be applied before switching to the guest,
so supply the per-cpu filter status to KVM.

Signed-off-by: James Clark <james.clark@xxxxxxx>
---
drivers/hwtracing/coresight/coresight-etm-perf.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c
index 5ca6278baff4..f78f05e656f5 100644
--- a/drivers/hwtracing/coresight/coresight-etm-perf.c
+++ b/drivers/hwtracing/coresight/coresight-etm-perf.c
@@ -9,6 +9,7 @@
#include <linux/coresight-pmu.h>
#include <linux/cpumask.h>
#include <linux/device.h>
+#include <linux/kvm_host.h>
#include <linux/list.h>
#include <linux/mm.h>
#include <linux/init.h>
@@ -510,6 +511,7 @@ static void etm_event_start(struct perf_event *event, int flags)
}

out:
+ kvm_etm_set_events(&event->attr);
/* Tell the perf core the event is alive */
event->hw.state = 0;
/* Save the event_data for this ETM */
@@ -627,6 +629,8 @@ static void etm_event_stop(struct perf_event *event, int mode)

/* Disabling the path make its elements available to other sessions */
coresight_disable_path(path);
+
+ kvm_etm_clr_events();
}

static int etm_event_add(struct perf_event *event, int mode)
--
2.34.1