This is a note to let you know that I've just added the patch titled hwtracing: hisi_ptt: Add dummy callback pmu::read() to the 6.1-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: hwtracing-hisi_ptt-add-dummy-callback-pmu-read.patch and it can be found in the queue-6.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 7c0b12081b74a0bb2e428de336015cc0f0ffd4b2 Author: Junhao He <hejunhao3@xxxxxxxxxx> Date: Tue Oct 10 16:47:31 2023 +0800 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: ff0de066b463 ("hwtracing: hisi_ptt: Add trace function support for HiSilicon PCIe Tune and Trace device") Signed-off-by: Junhao He <hejunhao3@xxxxxxxxxx> Signed-off-by: Yicong Yang <yangyicong@xxxxxxxxxxxxx> Acked-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx> Link: https://lore.kernel.org/r/20231010084731.30450-6-yangyicong@xxxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> 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);