Re: [PATCH v2 19/20] x86, mm: Make init_mem_mapping be able to be called several times

Konrad Rzeszutek Wilk
2013-03-11T13:17:30Z

On Sat, Mar 09, 2013 at 10:44:46PM -0800, Yinghai Lu wrote:
> Prepare to put page table on local nodes.
>
> Move calling of init_mem_mapping to early_initmem_init.
>
> Rework alloc_low_pages to alloc page table in following order:
> BRK, local node, low range
>
> Still only load_cr3 one time, otherwise we would break xen 64bit again.
>

We could also fix that. Now that the regression storm has passed
and I am able to spend some time on it we could make it a bit more
resistant.

> Signed-off-by: Yinghai Lu <yinghai@kernel.org>
> Cc: Pekka Enberg <penberg@kernel.org>
> Cc: Jacob Shin <jacob.shin@amd.com>
> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
> ---
> arch/x86/include/asm/pgtable.h | 2 +-
> arch/x86/kernel/setup.c | 1 -
> arch/x86/mm/init.c | 88 ++++++++++++++++++++++++----------------
> arch/x86/mm/numa.c | 24 +++++++++++
> 4 files changed, 79 insertions(+), 36 deletions(-)
>
> diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
> index 1e67223..868687c 100644
> --- a/arch/x86/include/asm/pgtable.h
> +++ b/arch/x86/include/asm/pgtable.h
> @@ -621,7 +621,7 @@ static inline int pgd_none(pgd_t pgd)
> #ifndef __ASSEMBLY__
>
> extern int direct_gbpages;
> -void init_mem_mapping(void);
> +void init_mem_mapping(unsigned long begin, unsigned long end);
> void early_alloc_pgt_buf(void);
>
> /* local pte updates need not use xchg for locking */
> diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
> index 86e1ec0..1cdc1a7 100644
> --- a/arch/x86/kernel/setup.c
> +++ b/arch/x86/kernel/setup.c
> @@ -1105,7 +1105,6 @@ void __init setup_arch(char **cmdline_p)
> acpi_boot_table_init();
> early_acpi_boot_init();
> early_initmem_init();
> - init_mem_mapping();
> memblock.current_limit = get_max_mapped();
> early_trap_pf_init();
>
> diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
> index 28b294f..8d0007a 100644
> --- a/arch/x86/mm/init.c
> +++ b/arch/x86/mm/init.c
> @@ -24,7 +24,10 @@ static unsigned long __initdata pgt_buf_start;
> static unsigned long __initdata pgt_buf_end;
> static unsigned long __initdata pgt_buf_top;
>
> -static unsigned long min_pfn_mapped;
> +static unsigned long low_min_pfn_mapped;
> +static unsigned long low_max_pfn_mapped;
> +static unsigned long local_min_pfn_mapped;
> +static unsigned long local_max_pfn_mapped;
>
> static bool __initdata can_use_brk_pgt = true;
>
> @@ -52,10 +55,17 @@ __ref void *alloc_low_pages(unsigned int num)
>
> if ((pgt_buf_end + num) > pgt_buf_top || !can_use_brk_pgt) {
> unsigned long ret;
> - if (min_pfn_mapped >= max_pfn_mapped)
> - panic("alloc_low_page: ran out of memory");
> - ret = memblock_find_in_range(min_pfn_mapped << PAGE_SHIFT,
> - max_pfn_mapped << PAGE_SHIFT,
> + if (local_min_pfn_mapped >= local_max_pfn_mapped) {
> + if (low_min_pfn_mapped >= low_max_pfn_mapped)
> + panic("alloc_low_page: ran out of memory");
> + ret = memblock_find_in_range(
> + low_min_pfn_mapped << PAGE_SHIFT,
> + low_max_pfn_mapped << PAGE_SHIFT,
> + PAGE_SIZE * num , PAGE_SIZE);
> + } else
> + ret = memblock_find_in_range(
> + local_min_pfn_mapped << PAGE_SHIFT,
> + local_max_pfn_mapped << PAGE_SHIFT,
> PAGE_SIZE * num , PAGE_SIZE);
> if (!ret)
> panic("alloc_low_page: can not alloc memory");
> @@ -387,60 +397,75 @@ static unsigned long __init init_range_memory_mapping(
>
> /* (PUD_SHIFT-PMD_SHIFT)/2 */
> #define STEP_SIZE_SHIFT 5
> -void __init init_mem_mapping(void)
> +void __init init_mem_mapping(unsigned long begin, unsigned long end)
> {
> - unsigned long end, real_end, start, last_start;
> + unsigned long real_end, start, last_start;
> unsigned long step_size;
> unsigned long addr;
> unsigned long mapped_ram_size = 0;
> unsigned long new_mapped_ram_size;
> + bool is_low = false;
> +
> + if (!begin) {
> + probe_page_size_mask();
> + /* the ISA range is always mapped regardless of memory holes */
> + init_memory_mapping(0, ISA_END_ADDRESS);
> + begin = ISA_END_ADDRESS;
> + is_low = true;
> + }
>
> - probe_page_size_mask();
> -
> -#ifdef CONFIG_X86_64
> - end = max_pfn << PAGE_SHIFT;
> -#else
> - end = max_low_pfn << PAGE_SHIFT;
> -#endif
> -
> - /* the ISA range is always mapped regardless of memory holes */
> - init_memory_mapping(0, ISA_END_ADDRESS);
> + if (begin >= end)
> + return;
>
> /* xen has big range in reserved near end of ram, skip it at first.*/
> - addr = memblock_find_in_range(ISA_END_ADDRESS, end, PMD_SIZE, PMD_SIZE);
> + addr = memblock_find_in_range(begin, end, PMD_SIZE, PMD_SIZE);
> real_end = addr + PMD_SIZE;
>
> /* step_size need to be small so pgt_buf from BRK could cover it */
> step_size = PMD_SIZE;
> - max_pfn_mapped = 0; /* will get exact value next */
> - min_pfn_mapped = real_end >> PAGE_SHIFT;
> + local_max_pfn_mapped = begin >> PAGE_SHIFT;
> + local_min_pfn_mapped = real_end >> PAGE_SHIFT;
> last_start = start = real_end;
> - while (last_start > ISA_END_ADDRESS) {
> + while (last_start > begin) {
> if (last_start > step_size) {
> start = round_down(last_start - 1, step_size);
> - if (start < ISA_END_ADDRESS)
> - start = ISA_END_ADDRESS;
> + if (start < begin)
> + start = begin;
> } else
> - start = ISA_END_ADDRESS;
> + start = begin;
> new_mapped_ram_size = init_range_memory_mapping(start,
> last_start);
> + if ((last_start >> PAGE_SHIFT) > local_max_pfn_mapped)
> + local_max_pfn_mapped = last_start >> PAGE_SHIFT;
> + local_min_pfn_mapped = start >> PAGE_SHIFT;
> last_start = start;
> - min_pfn_mapped = last_start >> PAGE_SHIFT;
> /* only increase step_size after big range get mapped */
> if (new_mapped_ram_size > mapped_ram_size)
> step_size <<= STEP_SIZE_SHIFT;
> mapped_ram_size += new_mapped_ram_size;
> }
>
> - if (real_end < end)
> + if (real_end < end) {
> init_range_memory_mapping(real_end, end);
> + if ((end >> PAGE_SHIFT) > local_max_pfn_mapped)
> + local_max_pfn_mapped = end >> PAGE_SHIFT;
> + }
>
> + if (is_low) {
> + low_min_pfn_mapped = local_min_pfn_mapped;
> + low_max_pfn_mapped = local_max_pfn_mapped;
> + }
> +}
> +
> +#ifndef CONFIG_NUMA
> +void __init early_initmem_init(void)
> +{
> #ifdef CONFIG_X86_64
> - if (max_pfn > max_low_pfn) {
> - /* can we preseve max_low_pfn ?*/
> + init_mem_mapping(0, max_pfn << PAGE_SHIFT);
> + if (max_pfn > max_low_pfn)
> max_low_pfn = max_pfn;
> - }
> #else
> + init_mem_mapping(0, max_low_pfn << PAGE_SHIFT);
> early_ioremap_page_table_range_init();
> #endif
>
> @@ -449,11 +474,6 @@ void __init init_mem_mapping(void)
>
> early_memtest(0, max_pfn_mapped << PAGE_SHIFT);
> }
> -
> -#ifndef CONFIG_NUMA
> -void __init early_initmem_init(void)
> -{
> -}
> #endif
>
> /*
> diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c
> index c2d4653..d3eb0c9 100644
> --- a/arch/x86/mm/numa.c
> +++ b/arch/x86/mm/numa.c
> @@ -17,8 +17,10 @@
> #include <asm/dma.h>
> #include <asm/acpi.h>
> #include <asm/amd_nb.h>
> +#include <asm/tlbflush.h>
>
> #include "numa_internal.h"
> +#include "mm_internal.h"
>
> int __initdata numa_off;
> nodemask_t numa_nodes_parsed __initdata;
> @@ -668,9 +670,31 @@ static void __init early_x86_numa_init(void)
> numa_init(dummy_numa_init);
> }
>
> +#ifdef CONFIG_X86_64
> +static void __init early_x86_numa_init_mapping(void)
> +{
> + init_mem_mapping(0, max_pfn << PAGE_SHIFT);
> + if (max_pfn > max_low_pfn)
> + max_low_pfn = max_pfn;
> +}
> +#else
> +static void __init early_x86_numa_init_mapping(void)
> +{
> + init_mem_mapping(0, max_low_pfn << PAGE_SHIFT);
> + early_ioremap_page_table_range_init();
> +}
> +#endif
> +
> void __init early_initmem_init(void)
> {
> early_x86_numa_init();
> +
> + early_x86_numa_init_mapping();
> +
> + load_cr3(swapper_pg_dir);
> + __flush_tlb_all();
> +
> + early_memtest(0, max_pfn_mapped<<PAGE_SHIFT);
> }
>
> void __init x86_numa_init(void)
> --
> 1.7.10.4
>