Re: [PATCH v2 4/5] drivers/xen: make sys-hypervisor.c explicitly non-modular

[Stefano Stabellini <stefano.stabellini@eu.citrix.com>]

On Sun, 21 Feb 2016, Paul Gortmaker wrote:
> The Kconfig currently controlling compilation of this code is:
> 
> config XEN_SYS_HYPERVISOR
>        bool "Create xen entries under /sys/hypervisor"
> 
> ...meaning that it currently is not being built as a module by anyone.
> 
> Lets remove the modular code that is essentially orphaned, so that
> when reading the driver there is no doubt it is builtin-only.
> 
> Since module_init translates to device_initcall in the non-modular
> case, the init ordering remains unchanged with this commit.  However
> one could argue that fs_initcall() might make more sense here.
> 
> This change means that the one line function xen_properties_destroy()
> has only one user left, and since that is inside an #ifdef, we just
> manually inline it there vs. adding more ifdeffery around the function
> to avoid compile warnings about "defined but not used".
> 
> In order to be consistent we also manually inline the other _destroy
> functions that are also just one line sysfs functions calls with only
> one call site remaing, even though they wouldn't need #ifdeffery.
> 
> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
> Cc: David Vrabel <david.vrabel@citrix.com>
> Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
> Cc: xen-devel@lists.xenproject.org
> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>


>  drivers/xen/sys-hypervisor.c | 59 ++++++--------------------------------------
>  1 file changed, 8 insertions(+), 51 deletions(-)
> 
> diff --git a/drivers/xen/sys-hypervisor.c b/drivers/xen/sys-hypervisor.c
> index b5a7342e0ba5..6881b3ceb675 100644
> --- a/drivers/xen/sys-hypervisor.c
> +++ b/drivers/xen/sys-hypervisor.c
> @@ -9,7 +9,7 @@
>  
>  #include <linux/slab.h>
>  #include <linux/kernel.h>
> -#include <linux/module.h>
> +#include <linux/init.h>
>  #include <linux/kobject.h>
>  #include <linux/err.h>
>  
> @@ -50,11 +50,6 @@ static int __init xen_sysfs_type_init(void)
>  	return sysfs_create_file(hypervisor_kobj, &type_attr.attr);
>  }
>  
> -static void xen_sysfs_type_destroy(void)
> -{
> -	sysfs_remove_file(hypervisor_kobj, &type_attr.attr);
> -}
> -
>  /* xen version attributes */
>  static ssize_t major_show(struct hyp_sysfs_attr *attr, char *buffer)
>  {
> @@ -111,11 +106,6 @@ static int __init xen_sysfs_version_init(void)
>  	return sysfs_create_group(hypervisor_kobj, &version_group);
>  }
>  
> -static void xen_sysfs_version_destroy(void)
> -{
> -	sysfs_remove_group(hypervisor_kobj, &version_group);
> -}
> -
>  /* UUID */
>  
>  static ssize_t uuid_show_fallback(struct hyp_sysfs_attr *attr, char *buffer)
> @@ -157,11 +147,6 @@ static int __init xen_sysfs_uuid_init(void)
>  	return sysfs_create_file(hypervisor_kobj, &uuid_attr.attr);
>  }
>  
> -static void xen_sysfs_uuid_destroy(void)
> -{
> -	sysfs_remove_file(hypervisor_kobj, &uuid_attr.attr);
> -}
> -
>  /* xen compilation attributes */
>  
>  static ssize_t compiler_show(struct hyp_sysfs_attr *attr, char *buffer)
> @@ -235,11 +220,6 @@ static int __init xen_compilation_init(void)
>  	return sysfs_create_group(hypervisor_kobj, &xen_compilation_group);
>  }
>  
> -static void xen_compilation_destroy(void)
> -{
> -	sysfs_remove_group(hypervisor_kobj, &xen_compilation_group);
> -}
> -
>  /* xen properties info */
>  
>  static ssize_t capabilities_show(struct hyp_sysfs_attr *attr, char *buffer)
> @@ -366,11 +346,6 @@ static int __init xen_properties_init(void)
>  	return sysfs_create_group(hypervisor_kobj, &xen_properties_group);
>  }
>  
> -static void xen_properties_destroy(void)
> -{
> -	sysfs_remove_group(hypervisor_kobj, &xen_properties_group);
> -}
> -
>  #ifdef CONFIG_XEN_HAVE_VPMU
>  struct pmu_mode {
>  	const char *name;
> @@ -484,11 +459,6 @@ static int __init xen_pmu_init(void)
>  {
>  	return sysfs_create_group(hypervisor_kobj, &xen_pmu_group);
>  }
> -
> -static void xen_pmu_destroy(void)
> -{
> -	sysfs_remove_group(hypervisor_kobj, &xen_pmu_group);
> -}
>  #endif
>  
>  static int __init hyper_sysfs_init(void)
> @@ -517,7 +487,8 @@ static int __init hyper_sysfs_init(void)
>  	if (xen_initial_domain()) {
>  		ret = xen_pmu_init();
>  		if (ret) {
> -			xen_properties_destroy();
> +			sysfs_remove_group(hypervisor_kobj,
> +					   &xen_properties_group);
>  			goto prop_out;
>  		}
>  	}
> @@ -525,31 +496,17 @@ static int __init hyper_sysfs_init(void)
>  	goto out;
>  
>  prop_out:
> -	xen_sysfs_uuid_destroy();
> +	sysfs_remove_file(hypervisor_kobj, &uuid_attr.attr);
>  uuid_out:
> -	xen_compilation_destroy();
> +	sysfs_remove_group(hypervisor_kobj, &xen_compilation_group);
>  comp_out:
> -	xen_sysfs_version_destroy();
> +	sysfs_remove_group(hypervisor_kobj, &version_group);
>  version_out:
> -	xen_sysfs_type_destroy();
> +	sysfs_remove_file(hypervisor_kobj, &type_attr.attr);
>  out:
>  	return ret;
>  }
> -
> -static void __exit hyper_sysfs_exit(void)
> -{
> -#ifdef CONFIG_XEN_HAVE_VPMU
> -	xen_pmu_destroy();
> -#endif
> -	xen_properties_destroy();
> -	xen_compilation_destroy();
> -	xen_sysfs_uuid_destroy();
> -	xen_sysfs_version_destroy();
> -	xen_sysfs_type_destroy();
> -
> -}
> -module_init(hyper_sysfs_init);
> -module_exit(hyper_sysfs_exit);
> +device_initcall(hyper_sysfs_init);
>  
>  static ssize_t hyp_sysfs_show(struct kobject *kobj,
>  			      struct attribute *attr,
> -- 
> 2.6.1
>