On Thu, Jan 24, 2019 at 04:51:53PM +0000, Mark Rutland wrote: > On Thu, Jan 24, 2019 at 04:19:33PM +0000, Christophe Leroy wrote: > > Since only the virtual address of allocated blocks is used, > > lets use functions returning directly virtual address. > > > > Those functions have the advantage of also zeroing the block. > > > > Suggested-by: Mike Rapoport <r...@linux.ibm.com> > > Acked-by: Mike Rapoport <r...@linux.ibm.com> > > Signed-off-by: Christophe Leroy <christophe.le...@c-s.fr> > > [...] > > > +static void *__init alloc_stack(void) > > +{ > > + void *ptr = memblock_alloc(THREAD_SIZE, THREAD_SIZE); > > + > > + if (!ptr) > > + panic("cannot allocate stacks"); > > + > > + return ptr; > > +} > > I believe memblock_alloc() will panic() if it cannot allocate memory, > since that goes: > > memblock_alloc() > -> memblock_alloc_try_nid() > -> panic() > > So you can get rid of the panic() here, or if you want a custom panic > message, you can use memblock_alloc_nopanic().
As we've already discussed it in [1], I'm working on removing the _nopanic() versions and dropping the panic() calls from memblock_alloc() and friends. I've posted v2 of the patches earlier this week [2]. > [...] [1] https://lore.kernel.org/lkml/20190108143428.GB14063@rapoport-lnx/ [2] https://lore.kernel.org/lkml/1548057848-15136-1-git-send-email-r...@linux.ibm.com/ > > static void *__init alloc_stack(unsigned long limit, int cpu) > > { > > - unsigned long pa; > > + void *ptr; > > > > BUILD_BUG_ON(STACK_INT_FRAME_SIZE % 16); > > > > - pa = memblock_alloc_base_nid(THREAD_SIZE, THREAD_SIZE, limit, > > - early_cpu_to_node(cpu), MEMBLOCK_NONE); > > - if (!pa) { > > - pa = memblock_alloc_base(THREAD_SIZE, THREAD_SIZE, limit); > > - if (!pa) > > - panic("cannot allocate stacks"); > > - } > > + ptr = memblock_alloc_try_nid(THREAD_SIZE, THREAD_SIZE, > > + MEMBLOCK_LOW_LIMIT, limit, > > + early_cpu_to_node(cpu)); > > + if (!ptr) > > + panic("cannot allocate stacks"); > > The same applies here -- memblock_alloc_try_nid() will panic itself > rather than returning NULL. > > Otherwise, this looks like a nice cleanup. With the panics removed (or > using the _nopanic() allocators), feel free to add: > > Acked-by: Mark Rutland <mark.rutl...@arm.com> > > Thanks, > Mark. > -- Sincerely yours, Mike.