On Wed, 14 Jun 2023 21:20:42 +0200, Stephan Gerhold wrote: > Right now dynamic reserved memory regions are allocated either > bottom-up or top-down, depending on the memblock setting of the > architecture. This is fine when the address is arbitrary. However, > when using "alloc-ranges" the regions are often placed somewhere > in the middle of (free) RAM, even if the range starts or ends next > to another (static) reservation. > > Try to detect this situation, and choose explicitly between bottom-up > or top-down to allocate the memory close to the other reservations: > > 1. If the "alloc-range" starts at the end or inside an existing > reservation, use bottom-up. > 2. If the "alloc-range" ends at the start or inside an existing > reservation, use top-down. > 3. If both or none is the case, keep the current > (architecture-specific) behavior. > > There are plenty of edge cases where only a more complex algorithm > would help, but even this simple approach helps in many cases to keep > the reserved memory (and therefore also the free memory) contiguous. > > Signed-off-by: Stephan Gerhold <stephan@xxxxxxxxxxx> > --- > drivers/of/of_reserved_mem.c | 55 ++++++++++++++++++++++++++++++++++++++++++-- > 1 file changed, 53 insertions(+), 2 deletions(-) > Applied, thanks!
