Re: [PATCH v2] mm/slab.c: use list_{empty_careful,last_entry} in drain_freelist

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Thu, 3 Dec 2015, Geliang Tang wrote:

>  	while (nr_freed < tofree && !list_empty(&n->slabs_free)) {
>
>  		spin_lock_irq(&n->list_lock);
> -		p = n->slabs_free.prev;
> -		if (p == &n->slabs_free) {
> +		if (list_empty_careful(&n->slabs_free)) {

We have taken the lock. Why do we need to be "careful"? list_empty()
shoudl work right?

>  			spin_unlock_irq(&n->list_lock);
>  			goto out;
>  		}
>
> -		page = list_entry(p, struct page, lru);
> +		page = list_last_entry(&n->slabs_free, struct page, lru);

last???

Would the the other new function that returns NULL on the empty list or
the pointer not be useful here too and save some code?

This patch seems to make it difficult to understand the code.

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>



[Index of Archives]     [Linux ARM Kernel]     [Linux ARM]     [Linux Omap]     [Fedora ARM]     [IETF Annouce]     [Bugtraq]     [Linux]     [Linux OMAP]     [Linux MIPS]     [ECOS]     [Asterisk Internet PBX]     [Linux API]