On Mon, Dec 01, 2008 at 05:02:50PM +0300, Alexey Starikovskiy wrote: > Pekka Enberg wrote: > >Hi, > > > >On Mon, 2008-12-01 at 16:12 +0300, Alexey Starikovskiy wrote: > > > >>>Actually I think it is also somewhat of a bugfix (not to mention that it > >>>seems like a good idea to share testing code with other operating > >>>systems). > >>> > >>It is not "kind of a bugfix". Caches were used to allocate all frequenly > >>created objects of fixed size. Removing native cache interface will > >>increase memory consumption and increase code size, and will make it > >>harder > >>to spot actual memory leaks. > >> > > > >Excuse me? > > > >Why do you think Nick's patch is going to _increase_ memory consumption? > >SLUB _already_ merges the ACPI caches with kmalloc caches so you won't > >see any difference there. For SLAB, it's a gain because there's not > >enough activity going on which results in lots of unused space in the > >slabs (which is, btw, the reason SLUB does slab merging in the first > >place). > > > > > Because SLAB has standard memory wells of 2^x size. None of cached ACPI > objects has exactly this size, so bigger block will be used. Plus, > internal ACPICA > caching will add some overhead. That's an insane looking caching thing now that I come to closely read the code. There is so much stuff there that I thought it must have been doing something useful which is why I didn't replace the Linux functions with kmalloc/kfree directly. There is really some operating system you support that has such a poor allocator that you think ACPI can do better in 300 lines of code? Why not just rip that whole thing out? > >I'm also wondering why you think it's going to increase text size. > >Unless the ACPI code is doing something weird, the kmalloc() and > >kzalloc() shouldn't be a problem at all. > > > > > if you don't use ACPI_USE_LOCAL_CACHE > ACPICA will enable it's own cache implementation, so it will increase > code size. > >For memory leaks, CONFIG_SLAB_LEAK has been in mainline for a long time > >plus there are the kmemleak patches floating around. So I fail to see > >how it's going to be harder to spot the memory leaks. > It will give you a memory leak, not the kind of it, right? > > After all, the > >rest of the kernel manages fine without a special wrapper, so how is > >ACPI any different here? > > > Do you have another interpreter in kernel space? So what makes it special? -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
