| Message ID | 20170418170553.026838125@linutronix.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 18 April 2017 at 11:04, Thomas Gleixner <tglx@linutronix.de> wrote: > From: Sebastian Andrzej Siewior <bigeasy@linutronix.de> > > etm_probe() 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. > > Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> > Signed-off-by: Thomas Gleixner <tglx@linutronix.de> > Cc: Mathieu Poirier <mathieu.poirier@linaro.org> > Cc: linux-arm-kernel@lists.infradead.org > > --- > drivers/hwtracing/coresight/coresight-etm3x.c | 12 ++++++------ > 1 file changed, 6 insertions(+), 6 deletions(-) > > --- a/drivers/hwtracing/coresight/coresight-etm3x.c > +++ b/drivers/hwtracing/coresight/coresight-etm3x.c > @@ -803,12 +803,12 @@ static int etm_probe(struct amba_device > dev_err(dev, "ETM arch init failed\n"); > > if (!etm_count++) { > - cpuhp_setup_state_nocalls(CPUHP_AP_ARM_CORESIGHT_STARTING, > - "arm/coresight:starting", > - etm_starting_cpu, etm_dying_cpu); > - ret = cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, > - "arm/coresight:online", > - etm_online_cpu, NULL); > + cpuhp_setup_state_nocalls_cpuslocked(CPUHP_AP_ARM_CORESIGHT_STARTING, > + "arm/coresight:starting", > + etm_starting_cpu, etm_dying_cpu); > + ret = cpuhp_setup_state_nocalls_cpuslocked(CPUHP_AP_ONLINE_DYN, > + "arm/coresight:online", > + etm_online_cpu, NULL); > if (ret < 0) > goto err_arch_supported; > hp_online = ret; > Acked-by: Mathieu Poirier <mathieu.poirier@linaro.org>
On Tue, Apr 18, 2017 at 07:04:50PM +0200, Thomas Gleixner wrote: > From: Sebastian Andrzej Siewior <bigeasy@linutronix.de> > > etm_probe() 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. > > Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> > Signed-off-by: Thomas Gleixner <tglx@linutronix.de> > Cc: Mathieu Poirier <mathieu.poirier@linaro.org> > Cc: linux-arm-kernel@lists.infradead.org > > --- > drivers/hwtracing/coresight/coresight-etm3x.c | 12 ++++++------ > 1 file changed, 6 insertions(+), 6 deletions(-) > > --- a/drivers/hwtracing/coresight/coresight-etm3x.c > +++ b/drivers/hwtracing/coresight/coresight-etm3x.c > @@ -803,12 +803,12 @@ static int etm_probe(struct amba_device > dev_err(dev, "ETM arch init failed\n"); > > if (!etm_count++) { > - cpuhp_setup_state_nocalls(CPUHP_AP_ARM_CORESIGHT_STARTING, > - "arm/coresight:starting", > - etm_starting_cpu, etm_dying_cpu); > - ret = cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, > - "arm/coresight:online", > - etm_online_cpu, NULL); > + cpuhp_setup_state_nocalls_cpuslocked(CPUHP_AP_ARM_CORESIGHT_STARTING, > + "arm/coresight:starting", > + etm_starting_cpu, etm_dying_cpu); > + ret = cpuhp_setup_state_nocalls_cpuslocked(CPUHP_AP_ONLINE_DYN, > + "arm/coresight:online", > + etm_online_cpu, NULL); Checkpatch complains about lines being over 80 characters long. It is better to keep the above or do as follow and make checkpatch happy? cpuhp_setup_state_nocalls_cpuslocked( PUHP_AP_ARM_CORESIGHT_STARTING, "arm/coresight:starting", etm_starting_cpu, etm_dying_cpu); ret = cpuhp_setup_state_nocalls_cpuslocked( CPUHP_AP_ONLINE_DYN, "arm/coresight:online", etm_online_cpu, NULL); Same for coresight-etm4x.c Thanks, Mathieu
--- a/drivers/hwtracing/coresight/coresight-etm3x.c +++ b/drivers/hwtracing/coresight/coresight-etm3x.c @@ -803,12 +803,12 @@ static int etm_probe(struct amba_device dev_err(dev, "ETM arch init failed\n"); if (!etm_count++) { - cpuhp_setup_state_nocalls(CPUHP_AP_ARM_CORESIGHT_STARTING, - "arm/coresight:starting", - etm_starting_cpu, etm_dying_cpu); - ret = cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, - "arm/coresight:online", - etm_online_cpu, NULL); + cpuhp_setup_state_nocalls_cpuslocked(CPUHP_AP_ARM_CORESIGHT_STARTING, + "arm/coresight:starting", + etm_starting_cpu, etm_dying_cpu); + ret = cpuhp_setup_state_nocalls_cpuslocked(CPUHP_AP_ONLINE_DYN, + "arm/coresight:online", + etm_online_cpu, NULL); if (ret < 0) goto err_arch_supported; hp_online = ret;