From: Junhao He hejunhao3@huawei.com
[ Upstream commit 7a6a9f1c5a0a875a421db798d4b2ee022dc1ee1a ]
The driver needs to migrate the perf context if the current using CPU going to teardown. By the time calling the cpuhp::teardown() callback the cpu_online_mask() hasn't updated yet and still includes the CPU going to teardown. In current driver's implementation we may migrate the context to the teardown CPU and leads to the below calltrace:
... [ 368.104662][ T932] task:cpuhp/0 state:D stack: 0 pid: 15 ppid: 2 flags:0x00000008 [ 368.113699][ T932] Call trace: [ 368.116834][ T932] __switch_to+0x7c/0xbc [ 368.120924][ T932] __schedule+0x338/0x6f0 [ 368.125098][ T932] schedule+0x50/0xe0 [ 368.128926][ T932] schedule_preempt_disabled+0x18/0x24 [ 368.134229][ T932] __mutex_lock.constprop.0+0x1d4/0x5dc [ 368.139617][ T932] __mutex_lock_slowpath+0x1c/0x30 [ 368.144573][ T932] mutex_lock+0x50/0x60 [ 368.148579][ T932] perf_pmu_migrate_context+0x84/0x2b0 [ 368.153884][ T932] hisi_pcie_pmu_offline_cpu+0x90/0xe0 [hisi_pcie_pmu] [ 368.160579][ T932] cpuhp_invoke_callback+0x2a0/0x650 [ 368.165707][ T932] cpuhp_thread_fun+0xe4/0x190 [ 368.170316][ T932] smpboot_thread_fn+0x15c/0x1a0 [ 368.175099][ T932] kthread+0x108/0x13c [ 368.179012][ T932] ret_from_fork+0x10/0x18 ...
Use function cpumask_any_but() to find one correct active cpu to fixes this issue.
Fixes: 8404b0fbc7fb ("drivers/perf: hisi: Add driver for HiSilicon PCIe PMU") Signed-off-by: Junhao He hejunhao3@huawei.com Reviewed-by: Jonathan Cameron Jonathan.Cameron@huawei.com Reviewed-by: Yicong Yang yangyicong@hisilicon.com Acked-by: Mark Rutland mark.rutland@arm.com Link: https://lore.kernel.org/r/20230608114326.27649-1-hejunhao3@huawei.com Signed-off-by: Will Deacon will@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/perf/hisilicon/hisi_pcie_pmu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/perf/hisilicon/hisi_pcie_pmu.c b/drivers/perf/hisilicon/hisi_pcie_pmu.c index 6fee0b6e163bb..e10fc7cb9493a 100644 --- a/drivers/perf/hisilicon/hisi_pcie_pmu.c +++ b/drivers/perf/hisilicon/hisi_pcie_pmu.c @@ -683,7 +683,7 @@ static int hisi_pcie_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node)
pcie_pmu->on_cpu = -1; /* Choose a new CPU from all online cpus. */ - target = cpumask_first(cpu_online_mask); + target = cpumask_any_but(cpu_online_mask, cpu); if (target >= nr_cpu_ids) { pci_err(pcie_pmu->pdev, "There is no CPU to set\n"); return 0;