lkml.org 
[lkml]   [2008]   [Feb]   [9]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [RFC PATCH] x86: explicit call to mmiotrace in do_page_fault()
>  	default n
> help
> This will build a kernel module called mmiotrace.
> + Making this a built-in is heavily discouraged.

why is this? Wouldn't it be nice if distros just shipped with this in their kernel by default
for example?

> -#ifdef CONFIG_PAGE_FAULT_HANDLERS
> -static HLIST_HEAD(pf_handlers); /* protected by RCU */
> -static DEFINE_SPINLOCK(pf_handlers_writer);
> +#ifdef CONFIG_MMIOTRACE_HOOKS
> +static pf_handler_func mmiotrace_pf_handler; /* protected by RCU */
> +static DEFINE_SPINLOCK(mmiotrace_handler_lock);
>
> -void register_page_fault_handler(struct pf_handler *new_pfh)
> +int mmiotrace_register_pf(pf_handler_func new_pfh)
> {
> + int ret = 0;
> unsigned long flags;
> - spin_lock_irqsave(&pf_handlers_writer, flags);
> - hlist_add_head_rcu(&new_pfh->hlist, &pf_handlers);
> - spin_unlock_irqrestore(&pf_handlers_writer, flags);
> + spin_lock_irqsave(&mmiotrace_handler_lock, flags);
> + if (mmiotrace_pf_handler)
> + ret = -EBUSY;
> + else
> + mmiotrace_pf_handler = new_pfh;
> + spin_unlock_irqrestore(&mmiotrace_handler_lock, flags);
> + return ret;
> }
> -EXPORT_SYMBOL_GPL(register_page_fault_handler);
> +EXPORT_SYMBOL_GPL(mmiotrace_register_pf);

why not use a weak function instead? should be a ton simpler.


\
 
 \ /
  Last update: 2008-02-09 19:05    [W:0.099 / U:0.116 seconds]
©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site