> On Thursday July 24,
a.p.zijlstra@chello.nl wrote:
> > Generic reserve management code.
> >
> > It provides methods to reserve and charge. Upon this, generic alloc/free style
> > reserve pools could be build, which could fully replace mempool_t
> > functionality.
>
> More comments on this patch .....
>
> > +void *___kmalloc_reserve(size_t size, gfp_t flags, int node, void *ip,
> > + struct mem_reserve *res, int *emerg);
> > +
> > +static inline
> > +void *__kmalloc_reserve(size_t size, gfp_t flags, int node, void *ip,
> > + struct mem_reserve *res, int *emerg)
> > +{
> > + void *obj;
> > +
> > + obj = __kmalloc_node_track_caller(size,
> > + flags | __GFP_NOMEMALLOC | __GFP_NOWARN, node, ip);
> > + if (!obj)
> > + obj = ___kmalloc_reserve(size, flags, node, ip, res, emerg);
> > +
> > + return obj;
> > +}
> > +
> > +#define kmalloc_reserve(size, gfp, node, res, emerg) \
> > + __kmalloc_reserve(size, gfp, node, \
> > + __builtin_return_address(0), res, emerg)
> > +
> ......
> > +/*
> > + * alloc wrappers
> > + */
> > +
> > +void *___kmalloc_reserve(size_t size, gfp_t flags, int node, void *ip,
> > + struct mem_reserve *res, int *emerg)
> > +{
> > + void *obj;
> > + gfp_t gfp;
> > +
> > + gfp = flags | __GFP_NOMEMALLOC | __GFP_NOWARN;
> > + obj = __kmalloc_node_track_caller(size, gfp, node, ip);
> > +
> > + if (obj || !(gfp_to_alloc_flags(flags) & ALLOC_NO_WATERMARKS))
> > + goto out;
> > +
> > + if (res && !mem_reserve_kmalloc_charge(res, size)) {
> > + if (!(flags & __GFP_WAIT))
> > + goto out;
> > +
> > + wait_event(res->waitqueue,
> > + mem_reserve_kmalloc_charge(res, size));
> > +
> > + obj = __kmalloc_node_track_caller(size, gfp, node, ip);
> > + if (obj) {
> > + mem_reserve_kmalloc_charge(res, -size);
> > + goto out;
> > + }
> > + }
> > +
> > + obj = __kmalloc_node_track_caller(size, flags, node, ip);
> > + WARN_ON(!obj);
> > + if (emerg)
> > + *emerg |= 1;
> > +
> > +out:
> > + return obj;
> > +}
>
> Two comments to be precise.
>
> 1/ __kmalloc_reserve attempts a __GFP_NOMEMALLOC allocation, and then
> if that fails, ___kmalloc_reserve immediately tries again.
> Is that pointless? Should the second one be removed?
