Commit 55e0a2fb authored by Junhao He's avatar Junhao He Committed by Suzuki K Poulose
Browse files

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



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: ff0de066 ("hwtracing: hisi_ptt: Add trace function support for HiSilicon PCIe Tune and Trace device")
Signed-off-by: default avatarJunhao He <hejunhao3@huawei.com>
Signed-off-by: default avatarYicong Yang <yangyicong@hisilicon.com>
Acked-by: default avatarJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: default avatarSuzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20231010084731.30450-6-yangyicong@huawei.com
parent 287e82cf

drivers/hwtracing/ptt/hisi_ptt.c

+5 −0
Original line number Diff line number Diff line
@@ -1178,6 +1178,10 @@ 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);
@@ -1221,6 +1225,7 @@ 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);