hwtracing: hisi_ptt: Add dummy callback pmu::read()

[ Upstream commit 55e0a2fb0cb5ab7c9c99c1ad4d3e6954de8b73a0 ]

When start trace with perf option "-C $cpu" and immediately stop it
with SIGTERM or others, the perf core will invoke pmu::read() while
the driver doesn't implement it. Add a dummy pmu::read() to avoid
any issues.

Fixes: ff0de066b4 ("hwtracing: hisi_ptt: Add trace function support for HiSilicon PCIe Tune and Trace device")
Signed-off-by: Junhao He <hejunhao3@huawei.com>
Signed-off-by: Yicong Yang <yangyicong@hisilicon.com>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20231010084731.30450-6-yangyicong@huawei.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Junhao He 2023-10-10 16:47:31 +08:00 committed by Greg Kroah-Hartman
parent 0b80e6af0d
commit 672976c28e

View file

@ -837,6 +837,10 @@ static void hisi_ptt_pmu_del(struct perf_event *event, int flags)
hisi_ptt_pmu_stop(event, PERF_EF_UPDATE);
}
static void hisi_ptt_pmu_read(struct perf_event *event)
{
}
static void hisi_ptt_remove_cpuhp_instance(void *hotplug_node)
{
cpuhp_state_remove_instance_nocalls(hisi_ptt_pmu_online, hotplug_node);
@ -880,6 +884,7 @@ static int hisi_ptt_register_pmu(struct hisi_ptt *hisi_ptt)
.stop = hisi_ptt_pmu_stop,
.add = hisi_ptt_pmu_add,
.del = hisi_ptt_pmu_del,
.read = hisi_ptt_pmu_read,
};
reg = readl(hisi_ptt->iobase + HISI_PTT_LOCATION);