Re: [PATCH 18/20] staging/lustre/libcfs: get rid of debugfs/lnet/debug_mb

Greg Kroah-Hartman
2015-07-14T02:46:57Z

On Mon, Jul 06, 2015 at 12:48:56PM -0400, green@linuxhacker.ru wrote:
> From: Oleg Drokin <green@linuxhacker.ru>
>
> It's just a fancy libcfs_debug_mb module parameter wrapper,
> so just add debug buffer size check and resizing and the same
> functionality now would be accessible via
> /sys/module/libcfs/parameters/libcfs_debug_mb
>
> Also add a symlink for backwards compatibility.
>
> Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
> ---
> drivers/staging/lustre/lustre/libcfs/debug.c | 37 ++++++++++++++++++++++--
> drivers/staging/lustre/lustre/libcfs/module.c | 32 ++------------------
> drivers/staging/lustre/lustre/libcfs/tracefile.c | 12 --------
> drivers/staging/lustre/lustre/libcfs/tracefile.h | 1 -
> 4 files changed, 37 insertions(+), 45 deletions(-)
>
> diff --git a/drivers/staging/lustre/lustre/libcfs/debug.c b/drivers/staging/lustre/lustre/libcfs/debug.c
> index 5ae7b65..e4c7129 100644
> --- a/drivers/staging/lustre/lustre/libcfs/debug.c
> +++ b/drivers/staging/lustre/lustre/libcfs/debug.c
> @@ -57,8 +57,39 @@ module_param(libcfs_debug, int, 0644);
> MODULE_PARM_DESC(libcfs_debug, "Lustre kernel debug mask");
> EXPORT_SYMBOL(libcfs_debug);
>
> +static int libcfs_param_debug_mb_set(const char *val,
> + const struct kernel_param *kp)
> +{
> + int rc;
> + unsigned num;
> +
> + rc = kstrtouint(val, 0, &num);
> + if (rc == -EINVAL)
> + return -EINVAL;
> +
> + if (!*((unsigned int *)kp->arg)) {
> + *((unsigned int *)kp->arg) = num;
> + return 0;
> + }
> +
> + rc = cfs_trace_set_debug_mb(num);
> +
> + if (!rc)
> + *((unsigned int *)kp->arg) = cfs_trace_get_debug_mb();
> +
> + return rc;
> +}
> +
> +static struct kernel_param_ops param_ops_debugmb = {
> + .set = libcfs_param_debug_mb_set,
> + .get = param_get_uint,
> +};
> +
> +#define param_check_debugmb(name, p) \
> + __param_check(name, p, unsigned int)
> +
> static unsigned int libcfs_debug_mb;
> -module_param(libcfs_debug_mb, uint, 0644);
> +module_param(libcfs_debug_mb, debugmb, 0644);

module_param wants a variable type as the second option, not a variable
name, how is this working?

thanks,

greg k-h