From: Pingfan Liu <kernelfans@gmail.com>
To: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org
Cc: Pingfan Liu <kernelfans@gmail.com>, Will Deacon <will@kernel.org>,
Mark Rutland <mark.rutland@arm.com>
Subject: [RFC 05/10] perf/arm-dsu: Make dsu_pmu_cpu_teardown() parallel
Date: Mon, 22 Aug 2022 10:15:15 +0800 [thread overview]
Message-ID: <20220822021520.6996-6-kernelfans@gmail.com> (raw)
In-Reply-To: <20220822021520.6996-1-kernelfans@gmail.com>
In the case of kexec quick reboot, dsu_pmu_cpu_teardown() confronts
parallel and lock are needed to protect the contest on a dsu_pmu.
Signed-off-by: Pingfan Liu <kernelfans@gmail.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
To: linux-arm-kernel@lists.infradead.org
To: linux-kernel@vger.kernel.org
---
drivers/perf/arm_dsu_pmu.c | 14 +++++++++++---
1 file changed, 11 insertions(+), 3 deletions(-)
diff --git a/drivers/perf/arm_dsu_pmu.c b/drivers/perf/arm_dsu_pmu.c
index a36698a90d2f..aa9f4393ff0c 100644
--- a/drivers/perf/arm_dsu_pmu.c
+++ b/drivers/perf/arm_dsu_pmu.c
@@ -833,16 +833,23 @@ static int dsu_pmu_cpu_teardown(unsigned int cpu, struct hlist_node *node)
struct dsu_pmu *dsu_pmu = hlist_entry_safe(node, struct dsu_pmu,
cpuhp_node);
- if (!cpumask_test_and_clear_cpu(cpu, &dsu_pmu->active_cpu))
+ raw_spin_lock(&dsu_pmu->pmu_lock);
+ if (!cpumask_test_and_clear_cpu(cpu, &dsu_pmu->active_cpu)) {
+ raw_spin_unlock(&dsu_pmu->pmu_lock);
return 0;
+ }
dst = dsu_pmu_get_online_cpu_any_but(dsu_pmu, cpu);
/* If there are no active CPUs in the DSU, leave IRQ disabled */
- if (dst >= nr_cpu_ids)
+ if (dst >= nr_cpu_ids) {
+ raw_spin_unlock(&dsu_pmu->pmu_lock);
return 0;
+ }
- perf_pmu_migrate_context(&dsu_pmu->pmu, cpu, dst);
+ /* dst should not be in dying mask. So after setting, blocking parallel */
dsu_pmu_set_active_cpu(dst, dsu_pmu);
+ raw_spin_unlock(&dsu_pmu->pmu_lock);
+ perf_pmu_migrate_context(&dsu_pmu->pmu, cpu, dst);
return 0;
}
@@ -858,6 +865,7 @@ static int __init dsu_pmu_init(void)
if (ret < 0)
return ret;
dsu_pmu_cpuhp_state = ret;
+ cpuhp_set_step_parallel(ret);
return platform_driver_register(&dsu_pmu_driver);
}
--
2.31.1
next prev parent reply other threads:[~2022-08-22 2:16 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-08-22 2:15 [RFC 00/10] arm64/riscv: Introduce fast kexec reboot Pingfan Liu
2022-08-22 2:15 ` [RFC 01/10] cpu/hotplug: Make __cpuhp_kick_ap() ready for async Pingfan Liu
2022-08-22 2:15 ` [RFC 02/10] cpu/hotplug: Compile smp_shutdown_nonboot_cpus() conditioned on CONFIG_SHUTDOWN_NONBOOT_CPUS Pingfan Liu
2022-08-22 2:15 ` [RFC 03/10] cpu/hotplug: Introduce fast kexec reboot Pingfan Liu
2022-08-22 2:15 ` [RFC 04/10] cpu/hotplug: Check the capability of kexec quick reboot Pingfan Liu
2022-08-22 2:15 ` Pingfan Liu [this message]
2022-08-22 2:15 ` [RFC 06/10] rcu/hotplug: Make rcutree_dead_cpu() parallel Pingfan Liu
2022-08-22 2:45 ` Paul E. McKenney
2022-08-23 1:50 ` Pingfan Liu
2022-08-23 3:01 ` Paul E. McKenney
2022-08-24 13:53 ` Pingfan Liu
2022-08-24 16:20 ` Paul E. McKenney
2022-08-24 17:26 ` Joel Fernandes
2022-08-24 19:21 ` Paul E. McKenney
2022-08-24 22:54 ` Joel Fernandes
2022-08-24 23:01 ` Paul E. McKenney
2022-08-31 16:15 ` Paul E. McKenney
2022-09-05 3:53 ` Pingfan Liu
2022-09-06 18:45 ` Paul E. McKenney
2022-08-22 18:08 ` Joel Fernandes
2022-08-23 1:56 ` Pingfan Liu
2022-08-23 3:14 ` Joel Fernandes
2022-08-24 13:38 ` Pingfan Liu
2022-08-24 13:44 ` Jason A. Donenfeld
2022-08-22 2:15 ` [RFC 07/10] lib/cpumask: Introduce cpumask_not_dying_but() Pingfan Liu
2022-08-22 14:15 ` Yury Norov
2022-08-23 7:29 ` Pingfan Liu
2022-08-22 2:15 ` [RFC 08/10] cpuhp: Replace cpumask_any_but(cpu_online_mask, cpu) Pingfan Liu
2022-08-22 2:15 ` [RFC 09/10] genirq/cpuhotplug: Ask migrate_one_irq() to migrate to a real online cpu Pingfan Liu
2022-08-22 2:15 ` [RFC 10/10] arm64: smp: Make __cpu_disable() parallel Pingfan Liu
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