| From: Sebastian Andrzej Siewior <bigeasy@linutronix.de> |
| Date: Wed, 24 May 2017 10:15:23 +0200 |
| Subject: [PATCH 12/32] hwtracing/coresight-etm4x: Use |
| cpuhp_setup_state_nocalls_cpuslocked() |
| |
| etm_probe4() holds get_online_cpus() while invoking |
| cpuhp_setup_state_nocalls(). |
| |
| cpuhp_setup_state_nocalls() invokes get_online_cpus() as well. This is |
| correct, but prevents the conversion of the hotplug locking to a percpu |
| rwsem. |
| |
| Use cpuhp_setup_state_nocalls_cpuslocked() to avoid the nested |
| call. Convert *_online_cpus() to the new interfaces while at it. |
| |
| Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> |
| Signed-off-by: Thomas Gleixner <tglx@linutronix.de> |
| Acked-by: Ingo Molnar <mingo@kernel.org> |
| Acked-by: Mathieu Poirier <mathieu.poirier@linaro.org> |
| Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> |
| Cc: Peter Zijlstra <peterz@infradead.org> |
| Cc: Steven Rostedt <rostedt@goodmis.org> |
| Cc: linux-arm-kernel@lists.infradead.org |
| Link: http://lkml.kernel.org/r/20170524081547.983493849@linutronix.de |
| --- |
| drivers/hwtracing/coresight/coresight-etm4x.c | 20 ++++++++++---------- |
| 1 file changed, 10 insertions(+), 10 deletions(-) |
| |
| --- a/drivers/hwtracing/coresight/coresight-etm4x.c |
| +++ b/drivers/hwtracing/coresight/coresight-etm4x.c |
| @@ -371,7 +371,7 @@ static void etm4_disable_sysfs(struct co |
| * after cpu online mask indicates the cpu is offline but before the |
| * DYING hotplug callback is serviced by the ETM driver. |
| */ |
| - get_online_cpus(); |
| + cpus_read_lock(); |
| spin_lock(&drvdata->spinlock); |
| |
| /* |
| @@ -381,7 +381,7 @@ static void etm4_disable_sysfs(struct co |
| smp_call_function_single(drvdata->cpu, etm4_disable_hw, drvdata, 1); |
| |
| spin_unlock(&drvdata->spinlock); |
| - put_online_cpus(); |
| + cpus_read_unlock(); |
| |
| dev_info(drvdata->dev, "ETM tracing disabled\n"); |
| } |
| @@ -982,7 +982,7 @@ static int etm4_probe(struct amba_device |
| |
| drvdata->cpu = pdata ? pdata->cpu : 0; |
| |
| - get_online_cpus(); |
| + cpus_read_lock(); |
| etmdrvdata[drvdata->cpu] = drvdata; |
| |
| if (smp_call_function_single(drvdata->cpu, |
| @@ -990,18 +990,18 @@ static int etm4_probe(struct amba_device |
| dev_err(dev, "ETM arch init failed\n"); |
| |
| if (!etm4_count++) { |
| - cpuhp_setup_state_nocalls(CPUHP_AP_ARM_CORESIGHT_STARTING, |
| - "arm/coresight4:starting", |
| - etm4_starting_cpu, etm4_dying_cpu); |
| - ret = cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, |
| - "arm/coresight4:online", |
| - etm4_online_cpu, NULL); |
| + cpuhp_setup_state_nocalls_cpuslocked(CPUHP_AP_ARM_CORESIGHT_STARTING, |
| + "arm/coresight4:starting", |
| + etm4_starting_cpu, etm4_dying_cpu); |
| + ret = cpuhp_setup_state_nocalls_cpuslocked(CPUHP_AP_ONLINE_DYN, |
| + "arm/coresight4:online", |
| + etm4_online_cpu, NULL); |
| if (ret < 0) |
| goto err_arch_supported; |
| hp_online = ret; |
| } |
| |
| - put_online_cpus(); |
| + cpus_read_unlock(); |
| |
| if (etm4_arch_supported(drvdata->arch) == false) { |
| ret = -EINVAL; |