Re: [PATCH] unicore32: switch to NO_BOOTMEM

From: Guan Xuetao
Date: Sun Jul 22 2018 - 04:15:22 EST



> -----Original Messages-----
> From: "Mike Rapoport" <rppt@xxxxxxxxxxxxxxxxxx>
> Sent Time: 2018-07-16 16:00:24 (Monday)
> To: "Guan Xuetao" <gxt@xxxxxxxxxx>
> Cc: "Michal Hocko" <mhocko@xxxxxxxxxx>, "Arnd Bergmann" <arnd@xxxxxxxx>, linux-mm@xxxxxxxxx, linux-kernel@xxxxxxxxxxxxxxx, "Mike Rapoport" <rppt@xxxxxxxxxxxxxxxxxx>
> Subject: [PATCH] unicore32: switch to NO_BOOTMEM
>
> The unicore32 already supports memblock and uses it for some early memory
> reservations, e.g initrd and the page tables.
>
> At some point unicore32 allocates the bootmem bitmap from the memblock and
> then hands over the memory reservations from memblock to bootmem.
>
> This patch removes the bootmem initialization and leaves memblock as the
> only boot time memory manager for unicore32.
>
> Signed-off-by: Mike Rapoport <rppt@xxxxxxxxxxxxxxxxxx>


Seems ok to unicore32. Thanks.
Acked-by: Guan Xuetao <gxt@xxxxxxxxxx>

> ---
>
> I couldn't get unicore32 toolchain as the only link I was able to find [1]
> gives me timeout, so the best I could do to check the changes was
>
> gcc <lots of flags> -c arch/unicore32/mm/init.c
>
> [1] http://mprc.pku.edu.cn/~guanxuetao/linux/uc4-1.0.5-hard.tgz
>
> arch/unicore32/Kconfig | 1 +
> arch/unicore32/mm/init.c | 54 +-----------------------------------------------
> 2 files changed, 2 insertions(+), 53 deletions(-)
>
> diff --git a/arch/unicore32/Kconfig b/arch/unicore32/Kconfig
> index 03f991e..cff4b9d 100644
> --- a/arch/unicore32/Kconfig
> +++ b/arch/unicore32/Kconfig
> @@ -5,6 +5,7 @@ config UNICORE32
> select ARCH_MIGHT_HAVE_PC_PARPORT
> select ARCH_MIGHT_HAVE_PC_SERIO
> select HAVE_MEMBLOCK
> + select NO_BOOTMEM
> select HAVE_GENERIC_DMA_COHERENT
> select HAVE_KERNEL_GZIP
> select HAVE_KERNEL_BZIP2
> diff --git a/arch/unicore32/mm/init.c b/arch/unicore32/mm/init.c
> index f4950fb..44ccc15 100644
> --- a/arch/unicore32/mm/init.c
> +++ b/arch/unicore32/mm/init.c
> @@ -84,58 +84,6 @@ static void __init find_limits(unsigned long *min, unsigned long *max_low,
> }
> }
>
> -static void __init uc32_bootmem_init(unsigned long start_pfn,
> - unsigned long end_pfn)
> -{
> - struct memblock_region *reg;
> - unsigned int boot_pages;
> - phys_addr_t bitmap;
> - pg_data_t *pgdat;
> -
> - /*
> - * Allocate the bootmem bitmap page. This must be in a region
> - * of memory which has already been mapped.
> - */
> - boot_pages = bootmem_bootmap_pages(end_pfn - start_pfn);
> - bitmap = memblock_alloc_base(boot_pages << PAGE_SHIFT, L1_CACHE_BYTES,
> - __pfn_to_phys(end_pfn));
> -
> - /*
> - * Initialise the bootmem allocator, handing the
> - * memory banks over to bootmem.
> - */
> - node_set_online(0);
> - pgdat = NODE_DATA(0);
> - init_bootmem_node(pgdat, __phys_to_pfn(bitmap), start_pfn, end_pfn);
> -
> - /* Free the lowmem regions from memblock into bootmem. */
> - for_each_memblock(memory, reg) {
> - unsigned long start = memblock_region_memory_base_pfn(reg);
> - unsigned long end = memblock_region_memory_end_pfn(reg);
> -
> - if (end >= end_pfn)
> - end = end_pfn;
> - if (start >= end)
> - break;
> -
> - free_bootmem(__pfn_to_phys(start), (end - start) << PAGE_SHIFT);
> - }
> -
> - /* Reserve the lowmem memblock reserved regions in bootmem. */
> - for_each_memblock(reserved, reg) {
> - unsigned long start = memblock_region_reserved_base_pfn(reg);
> - unsigned long end = memblock_region_reserved_end_pfn(reg);
> -
> - if (end >= end_pfn)
> - end = end_pfn;
> - if (start >= end)
> - break;
> -
> - reserve_bootmem(__pfn_to_phys(start),
> - (end - start) << PAGE_SHIFT, BOOTMEM_DEFAULT);
> - }
> -}
> -
> static void __init uc32_bootmem_free(unsigned long min, unsigned long max_low,
> unsigned long max_high)
> {
> @@ -232,7 +180,7 @@ void __init bootmem_init(void)
>
> find_limits(&min, &max_low, &max_high);
>
> - uc32_bootmem_init(min, max_low);
> + node_set_online(0);
>
> #ifdef CONFIG_SWIOTLB
> swiotlb_init(1);
> --
> 2.7.4