Interesting. I had similar problem with recursive memory allocation while working on database engine. Solution was relatively simple, reorder method calls inside alocator, so that memory is allocated BEFORE cleanup progresses.
I think Linux memory allocator devs could keep small preallocated buffer, return allocated space, and schedule independent maintenance after buffer gets low.
> I think Linux memory allocator devs could keep small preallocated buffer, return allocated space, and schedule independent maintenance after buffer gets low.
It's already a possibilty. The gfp flags argument to kmalloc() may have the __GFP_HIGH flag set: "This allocation has high priority and may use emergency pools". However, it's use is generally discouraged and can really be only used in extremely specific situations.
I think Linux memory allocator devs could keep small preallocated buffer, return allocated space, and schedule independent maintenance after buffer gets low.