From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Lezcano Subject: Re: [PATCH 17/21] cpuidle: avoid unnecessary kzalloc/free of struct cpuidle_driver_kobj Date: Thu, 26 Sep 2013 00:16:57 +0200 Message-ID: <524360D9.3000706@linaro.org> References: Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Viresh Kumar , rjw@sisk.pl Cc: linaro-kernel@lists.linaro.org, patches@linaro.org, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-pm@vger.kernel.org On 09/22/2013 03:21 AM, Viresh Kumar wrote: > For CONFIG_CPU_IDLE_MULTIPLE_DRIVERS, struct cpuidle_device always ne= eds to > allocate struct cpuidle_driver_kobj for all CPUs and so there is no r= eal need to > have a pointer to it inside struct cpuidle_device. >=20 > This patch makes a object instance of struct cpuidle_driver_kobj insi= de struct > cpuidle_device instead of a pointer. >=20 > It also makes kobj_driver dependent on CONFIG_CPU_IDLE_MULTIPLE_DRIVE= RS. >=20 > Signed-off-by: Viresh Kumar Comment similar to patch 16/21. If you try to offline/online a cpu, tha= t should lead to a kernel warning. > --- > drivers/cpuidle/sysfs.c | 20 +++----------------- > include/linux/cpuidle.h | 11 +++++++++-- > 2 files changed, 12 insertions(+), 19 deletions(-) >=20 > diff --git a/drivers/cpuidle/sysfs.c b/drivers/cpuidle/sysfs.c > index db0aac3..3386d64 100644 > --- a/drivers/cpuidle/sysfs.c > +++ b/drivers/cpuidle/sysfs.c > @@ -439,12 +439,6 @@ static void cpuidle_remove_state_sysfs(struct cp= uidle_device *device) > static struct cpuidle_driver_attr attr_driver_##_name =3D \ > __ATTR(_name, 0644, show, NULL) > =20 > -struct cpuidle_driver_kobj { > - struct cpuidle_driver *drv; > - struct completion kobj_unregister; > - struct kobject kobj; > -}; > - > struct cpuidle_driver_attr { > struct attribute attr; > ssize_t (*show)(struct cpuidle_driver *, char *); > @@ -518,27 +512,20 @@ static struct kobj_type ktype_driver_cpuidle =3D= { > */ > static int cpuidle_add_driver_sysfs(struct cpuidle_device *dev) > { > - struct cpuidle_driver_kobj *kdrv; > + struct cpuidle_driver_kobj *kdrv =3D &dev->kobj_driver; > struct cpuidle_device_kobj *kdev =3D &dev->kobj_dev; > struct cpuidle_driver *drv =3D cpuidle_get_cpu_driver(dev); > int ret; > =20 > - kdrv =3D kzalloc(sizeof(*kdrv), GFP_KERNEL); > - if (!kdrv) > - return -ENOMEM; > - > kdrv->drv =3D drv; > init_completion(&kdrv->kobj_unregister); > =20 > ret =3D kobject_init_and_add(&kdrv->kobj, &ktype_driver_cpuidle, > &kdev->kobj, "driver"); > - if (ret) { > - kfree(kdrv); > + if (ret) > return ret; > - } > =20 > kobject_uevent(&kdrv->kobj, KOBJ_ADD); > - dev->kobj_driver =3D kdrv; > =20 > return ret; > } > @@ -549,10 +536,9 @@ static int cpuidle_add_driver_sysfs(struct cpuid= le_device *dev) > */ > static void cpuidle_remove_driver_sysfs(struct cpuidle_device *dev) > { > - struct cpuidle_driver_kobj *kdrv =3D dev->kobj_driver; > + struct cpuidle_driver_kobj *kdrv =3D &dev->kobj_driver; > kobject_put(&kdrv->kobj); > wait_for_completion(&kdrv->kobj_unregister); > - kfree(kdrv); > } > #else > static inline int cpuidle_add_driver_sysfs(struct cpuidle_device *de= v) > diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h > index 1fc5cb5..0f0da17 100644 > --- a/include/linux/cpuidle.h > +++ b/include/linux/cpuidle.h > @@ -62,7 +62,6 @@ struct cpuidle_state { > #define CPUIDLE_DRIVER_FLAGS_MASK (0xFFFF0000) > =20 > struct cpuidle_state_kobj; > -struct cpuidle_driver_kobj; > =20 > struct cpuidle_device_kobj { > struct cpuidle_device *dev; > @@ -70,6 +69,12 @@ struct cpuidle_device_kobj { > struct kobject kobj; > }; > =20 > +struct cpuidle_driver_kobj { > + struct cpuidle_driver *drv; > + struct completion kobj_unregister; > + struct kobject kobj; > +}; > + > struct cpuidle_device { > unsigned int registered:1; > unsigned int enabled:1; > @@ -79,7 +84,9 @@ struct cpuidle_device { > int state_count; > struct cpuidle_state_usage states_usage[CPUIDLE_STATE_MAX]; > struct cpuidle_state_kobj *kobjs[CPUIDLE_STATE_MAX]; > - struct cpuidle_driver_kobj *kobj_driver; > +#ifdef CONFIG_CPU_IDLE_MULTIPLE_DRIVERS > + struct cpuidle_driver_kobj kobj_driver; > +#endif > struct cpuidle_device_kobj kobj_dev; > struct list_head device_list; > =20 >=20 --=20 Linaro.org =E2=94=82 Open source software for= ARM SoCs =46ollow Linaro: Facebook | Twitter | Blog