On 01/05/2017 11:02 PM, Hari Bathini wrote:
> fadump supports specifying memory to reserve for fadump's crash kernel
> with fadump_reserve_mem kernel parameter. This parameter currently
> supports passing a fixed memory size, like fadump_reserve_mem=<size>
> only. This patch aims to add support for other syntaxes like range-based
> memory size <range1>:<size1>[,<range2>:<size2>,<range3>:<size3>,...]
> which allows using the same parameter to boot the kernel with different
> system RAM sizes.
>
> As crashkernel parameter already supports the above mentioned syntaxes,
> this patch deprecates fadump_reserve_mem parameter and reuses crashkernel
> parameter instead, to specify memory for fadump's crash kernel memory
> reservation as well. If any offset is provided in crashkernel parameter,
> it will be ignored in case of fadump, as fadump reserves memory at end
> of RAM.
>
> Advantages using crashkernel parameter instead of fadump_reserve_mem
> parameter are one less kernel parameter overall, code reuse and support
> for multiple syntaxes to specify memory.
>
> Suggested-by: Dave Young <dyoung at redhat.com>
> Signed-off-by: Hari Bathini <hbathini at linux.vnet.ibm.com>
Reviewed-by: Mahesh Salgaonkar <mahesh at linux.vnet.ibm.com>
> ---
> arch/powerpc/kernel/fadump.c | 23 ++++++++++-------------
> 1 file changed, 10 insertions(+), 13 deletions(-)
>
> diff --git a/arch/powerpc/kernel/fadump.c b/arch/powerpc/kernel/fadump.c
> index db0b339..de7d39a 100644
> --- a/arch/powerpc/kernel/fadump.c
> +++ b/arch/powerpc/kernel/fadump.c
> @@ -210,14 +210,20 @@ static unsigned long init_fadump_mem_struct(struct fadump_mem_struct *fdm,
> */
> static inline unsigned long fadump_calculate_reserve_size(void)
> {
> - unsigned long size;
> + int ret;
> + unsigned long long base, size;
>
> /*
> - * Check if the size is specified through fadump_reserve_mem= cmdline
> - * option. If yes, then use that.
> + * Check if the size is specified through crashkernel= cmdline
> + * option. If yes, then use that but ignore base as fadump
> + * reserves memory at end of RAM.
> */
> - if (fw_dump.reserve_bootvar)
> + ret = parse_crashkernel(boot_command_line, memblock_phys_mem_size(),
> + &size, &base);
> + if (ret == 0 && size > 0) {
> + fw_dump.reserve_bootvar = (unsigned long)size;
> return fw_dump.reserve_bootvar;
> + }
>
> /* divide by 20 to get 5% of value */
> size = memblock_end_of_DRAM() / 20;
> @@ -353,15 +359,6 @@ static int __init early_fadump_param(char *p)
> }
> early_param("fadump", early_fadump_param);
>
> -/* Look for fadump_reserve_mem= cmdline option */
> -static int __init early_fadump_reserve_mem(char *p)
> -{
> - if (p)
> - fw_dump.reserve_bootvar = memparse(p, &p);
> - return 0;
> -}
> -early_param("fadump_reserve_mem", early_fadump_reserve_mem);
> -
> static void register_fw_dump(struct fadump_mem_struct *fdm)
> {
> int rc;
>
