[Crash-utility] [PATCH] defs.h: Refine the FILL_PML4() macro

[Dave Anderson]

Queued for crash-7.2.1:

  https://github.com/crash-utility/crash/commit/3fe2663be5c6a5b160025a5a65b655a570e7e79e

Thanks,
  Dave


----- Original Message -----
> The FILL_PML4() updates the machdep->machspec->last_pml4_read every time.
> 
> But the last_pml4_read only need to be updated when IS_LAST_PML4_READ()
> macro returns false.
> 
> Refine the FILL_PML4() to keep it simply and do some cleanup.
> 
> Signed-off-by: Dou Liyang <douly.fnst at cn.fujitsu.com>
> ---
>  defs.h | 38 ++++++++++++++++++--------------------
>  1 file changed, 18 insertions(+), 20 deletions(-)
> 
> diff --git a/defs.h b/defs.h
> index 97738a6..9a33b41 100644
> --- a/defs.h
> +++ b/defs.h
> @@ -3344,7 +3344,7 @@ struct arm64_stackframe {
>  #define PTRS_PER_P4D         512
>  
>  #define __PGDIR_SHIFT  (machdep->machspec->pgdir_shift)
> -
> +
>  #define pml4_index(address) (((address) >> PML4_SHIFT) & (PTRS_PER_PML4-1))
>  #define p4d_index(address)  (((address) >> P4D_SHIFT) & (PTRS_PER_P4D - 1))
>  #define pgd_index(address)  (((address) >> __PGDIR_SHIFT) &
>  (PTRS_PER_PGD-1))
> @@ -3353,26 +3353,24 @@ struct arm64_stackframe {
>  
>  #define IS_LAST_PML4_READ(pml4) ((ulong)(pml4) ==
>  machdep->machspec->last_pml4_read)
>  
> -#define FILL_PML4() { \
> -	if (!(pc->flags & RUNTIME) || ACTIVE()) { \
> -		if (!IS_LAST_PML4_READ(vt->kernel_pgd[0])) \
> -                    readmem(vt->kernel_pgd[0], KVADDR,
> machdep->machspec->pml4, \
> -                        PAGESIZE(), "init_level4_pgt", FAULT_ON_ERROR); \
> -                machdep->machspec->last_pml4_read =
> (ulong)(vt->kernel_pgd[0]); \
> -	} \
> -}
> +#define FILL_PML4() 									\
> +	if (!(pc->flags & RUNTIME) || ACTIVE()) { 					\
> +		if (!IS_LAST_PML4_READ(vt->kernel_pgd[0])) { 				\
> +			readmem(vt->kernel_pgd[0], KVADDR, machdep->machspec->pml4, 	\
> +					PAGESIZE(), "init_level4_pgt", FAULT_ON_ERROR); \
> +			machdep->machspec->last_pml4_read = (ulong)(vt->kernel_pgd[0]); \
> +		} 									\
> +	}
>  
> -#define FILL_PML4_HYPER() { \
> -	if (!machdep->machspec->last_pml4_read) { \
> -		unsigned long idle_pg_table = \
> -		    symbol_exists("idle_pg_table_4") ? symbol_value("idle_pg_table_4") : \
> -			symbol_value("idle_pg_table"); \
> -		readmem(idle_pg_table, KVADDR, \
> -			machdep->machspec->pml4, PAGESIZE(), "idle_pg_table", \
> -			FAULT_ON_ERROR); \
> -		machdep->machspec->last_pml4_read = idle_pg_table; \
> -	}\
> -}
> +#define FILL_PML4_HYPER() 								\
> +	if (!machdep->machspec->last_pml4_read) { 					\
> +		unsigned long idle_pg_table = symbol_exists("idle_pg_table_4") ? 	\
> +						symbol_value("idle_pg_table_4") : 	\
> +						symbol_value("idle_pg_table"); 	\
> +		readmem(idle_pg_table, KVADDR, machdep->machspec->pml4, PAGESIZE(), 	\
> +				"idle_pg_table", FAULT_ON_ERROR); 			\
> +		machdep->machspec->last_pml4_read = idle_pg_table; 			\
> +	}
>  
>  #define IS_LAST_UPML_READ(pml) ((ulong)(pml) ==
>  machdep->machspec->last_upml_read)
>  
> --
> 2.14.3
> 
> 
> 
>