6.1-stable review patch. If anyone has any objections, please let me know.
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From: Junhao He hejunhao3@huawei.com
[ 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: ff0de066b463 ("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 --- drivers/hwtracing/ptt/hisi_ptt.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/drivers/hwtracing/ptt/hisi_ptt.c b/drivers/hwtracing/ptt/hisi_ptt.c index 4140efd664097..016220ba0addd 100644 --- a/drivers/hwtracing/ptt/hisi_ptt.c +++ b/drivers/hwtracing/ptt/hisi_ptt.c @@ -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);