[v2,13/17] x86/setup: simplify initrd relocation and reservation
diff mbox series

Message ID 20200802163601.8189-14-rppt@kernel.org
State Superseded
Headers show
Series
  • memblock: seasonal cleaning^w cleanup
Related show

Commit Message

Mike Rapoport Aug. 2, 2020, 4:35 p.m. UTC
From: Mike Rapoport <rppt@linux.ibm.com>

Currently, initrd image is reserved very early during setup and then it
might be relocated and re-reserved after the initial physical memory
mapping is created. The "late" reservation of memblock verifies that mapped
memory size exceeds the size of initrd, the checks whether the relocation
required and, if yes, relocates inirtd to a new memory allocated from
memblock and frees the old location.

The check for memory size is excessive as memblock allocation will anyway
fail if there is not enough memory. Besides, there is no point to allocate
memory from memblock using memblock_find_in_range() + memblock_reserve()
when there exists memblock_phys_alloc_range() with required functionality.

Remove the redundant check and simplify memblock allocation.

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
---
 arch/x86/kernel/setup.c | 16 +++-------------
 1 file changed, 3 insertions(+), 13 deletions(-)

Comments

Ingo Molnar Aug. 2, 2020, 6:01 p.m. UTC | #1
* Mike Rapoport <rppt@kernel.org> wrote:

> From: Mike Rapoport <rppt@linux.ibm.com>
> 
> Currently, initrd image is reserved very early during setup and then it
> might be relocated and re-reserved after the initial physical memory
> mapping is created. The "late" reservation of memblock verifies that mapped
> memory size exceeds the size of initrd, the checks whether the relocation
> required and, if yes, relocates inirtd to a new memory allocated from
> memblock and frees the old location.
> 
> The check for memory size is excessive as memblock allocation will anyway
> fail if there is not enough memory. Besides, there is no point to allocate
> memory from memblock using memblock_find_in_range() + memblock_reserve()
> when there exists memblock_phys_alloc_range() with required functionality.
> 
> Remove the redundant check and simplify memblock allocation.
> 
> Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>

Assuming there's no hidden dependency here breaking something:

  Acked-by: Ingo Molnar <mingo@kernel.org>

Thanks,

	Ingo
Baoquan He Aug. 5, 2020, 4:20 a.m. UTC | #2
On 08/02/20 at 07:35pm, Mike Rapoport wrote:
> From: Mike Rapoport <rppt@linux.ibm.com>
> 
> Currently, initrd image is reserved very early during setup and then it
> might be relocated and re-reserved after the initial physical memory
> mapping is created. The "late" reservation of memblock verifies that mapped
> memory size exceeds the size of initrd, the checks whether the relocation
                                          ~ then?
> required and, if yes, relocates inirtd to a new memory allocated from
> memblock and frees the old location.
> 
> The check for memory size is excessive as memblock allocation will anyway
> fail if there is not enough memory. Besides, there is no point to allocate
> memory from memblock using memblock_find_in_range() + memblock_reserve()
> when there exists memblock_phys_alloc_range() with required functionality.
> 
> Remove the redundant check and simplify memblock allocation.
> 
> Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
> ---
>  arch/x86/kernel/setup.c | 16 +++-------------
>  1 file changed, 3 insertions(+), 13 deletions(-)
> 
> diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
> index a3767e74c758..d8de4053c5e8 100644
> --- a/arch/x86/kernel/setup.c
> +++ b/arch/x86/kernel/setup.c
> @@ -262,16 +262,12 @@ static void __init relocate_initrd(void)
>  	u64 area_size     = PAGE_ALIGN(ramdisk_size);
>  
>  	/* We need to move the initrd down into directly mapped mem */
> -	relocated_ramdisk = memblock_find_in_range(0, PFN_PHYS(max_pfn_mapped),
> -						   area_size, PAGE_SIZE);
> -
> +	relocated_ramdisk = memblock_phys_alloc_range(area_size, PAGE_SIZE, 0,
> +						      PFN_PHYS(max_pfn_mapped));
>  	if (!relocated_ramdisk)
>  		panic("Cannot find place for new RAMDISK of size %lld\n",
>  		      ramdisk_size);
>  
> -	/* Note: this includes all the mem currently occupied by
> -	   the initrd, we rely on that fact to keep the data intact. */
> -	memblock_reserve(relocated_ramdisk, area_size);
>  	initrd_start = relocated_ramdisk + PAGE_OFFSET;
>  	initrd_end   = initrd_start + ramdisk_size;
>  	printk(KERN_INFO "Allocated new RAMDISK: [mem %#010llx-%#010llx]\n",
> @@ -298,13 +294,13 @@ static void __init early_reserve_initrd(void)
>  
>  	memblock_reserve(ramdisk_image, ramdisk_end - ramdisk_image);
>  }
> +
>  static void __init reserve_initrd(void)
>  {
>  	/* Assume only end is not page aligned */
>  	u64 ramdisk_image = get_ramdisk_image();
>  	u64 ramdisk_size  = get_ramdisk_size();
>  	u64 ramdisk_end   = PAGE_ALIGN(ramdisk_image + ramdisk_size);
> -	u64 mapped_size;
>  
>  	if (!boot_params.hdr.type_of_loader ||
>  	    !ramdisk_image || !ramdisk_size)
> @@ -312,12 +308,6 @@ static void __init reserve_initrd(void)
>  
>  	initrd_start = 0;
>  
> -	mapped_size = memblock_mem_size(max_pfn_mapped);
> -	if (ramdisk_size >= (mapped_size>>1))
> -		panic("initrd too large to handle, "
> -		       "disabling initrd (%lld needed, %lld available)\n",
> -		       ramdisk_size, mapped_size>>1);

Reviewed-by: Baoquan He <bhe@redhat.com>

> -
>  	printk(KERN_INFO "RAMDISK: [mem %#010llx-%#010llx]\n", ramdisk_image,
>  			ramdisk_end - 1);
>  
> -- 
> 2.26.2
>
Mike Rapoport Aug. 5, 2020, 5:59 a.m. UTC | #3
On Wed, Aug 05, 2020 at 12:20:24PM +0800, Baoquan He wrote:
> On 08/02/20 at 07:35pm, Mike Rapoport wrote:
> > From: Mike Rapoport <rppt@linux.ibm.com>
> > 
> > Currently, initrd image is reserved very early during setup and then it
> > might be relocated and re-reserved after the initial physical memory
> > mapping is created. The "late" reservation of memblock verifies that mapped
> > memory size exceeds the size of initrd, the checks whether the relocation
>                                           ~ then?

Right, thanks!

> > required and, if yes, relocates inirtd to a new memory allocated from
> > memblock and frees the old location.

Patch
diff mbox series

diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index a3767e74c758..d8de4053c5e8 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -262,16 +262,12 @@  static void __init relocate_initrd(void)
 	u64 area_size     = PAGE_ALIGN(ramdisk_size);
 
 	/* We need to move the initrd down into directly mapped mem */
-	relocated_ramdisk = memblock_find_in_range(0, PFN_PHYS(max_pfn_mapped),
-						   area_size, PAGE_SIZE);
-
+	relocated_ramdisk = memblock_phys_alloc_range(area_size, PAGE_SIZE, 0,
+						      PFN_PHYS(max_pfn_mapped));
 	if (!relocated_ramdisk)
 		panic("Cannot find place for new RAMDISK of size %lld\n",
 		      ramdisk_size);
 
-	/* Note: this includes all the mem currently occupied by
-	   the initrd, we rely on that fact to keep the data intact. */
-	memblock_reserve(relocated_ramdisk, area_size);
 	initrd_start = relocated_ramdisk + PAGE_OFFSET;
 	initrd_end   = initrd_start + ramdisk_size;
 	printk(KERN_INFO "Allocated new RAMDISK: [mem %#010llx-%#010llx]\n",
@@ -298,13 +294,13 @@  static void __init early_reserve_initrd(void)
 
 	memblock_reserve(ramdisk_image, ramdisk_end - ramdisk_image);
 }
+
 static void __init reserve_initrd(void)
 {
 	/* Assume only end is not page aligned */
 	u64 ramdisk_image = get_ramdisk_image();
 	u64 ramdisk_size  = get_ramdisk_size();
 	u64 ramdisk_end   = PAGE_ALIGN(ramdisk_image + ramdisk_size);
-	u64 mapped_size;
 
 	if (!boot_params.hdr.type_of_loader ||
 	    !ramdisk_image || !ramdisk_size)
@@ -312,12 +308,6 @@  static void __init reserve_initrd(void)
 
 	initrd_start = 0;
 
-	mapped_size = memblock_mem_size(max_pfn_mapped);
-	if (ramdisk_size >= (mapped_size>>1))
-		panic("initrd too large to handle, "
-		       "disabling initrd (%lld needed, %lld available)\n",
-		       ramdisk_size, mapped_size>>1);
-
 	printk(KERN_INFO "RAMDISK: [mem %#010llx-%#010llx]\n", ramdisk_image,
 			ramdisk_end - 1);