Re: [RESEND][PATCH v2 2/2] powerpc/fadump: parse fadump reserve memory size based on memory range

From: Michael Ellerman
Date: Thu Aug 04 2016 - 05:46:10 EST


Hari Bathini <hbathini@xxxxxxxxxxxxxxxxxx> writes:
...
> /**
> * fadump_calculate_reserve_size(): reserve variable boot area 5% of System RAM
> *
> @@ -212,12 +262,17 @@ static inline unsigned long fadump_calculate_reserve_size(void)
> {
> unsigned long size;
>
> + /* sets fw_dump.reserve_bootvar */
> + parse_fadump_reserve_mem();
> +
> /*
> * Check if the size is specified through fadump_reserve_mem= cmdline
> * option. If yes, then use that.
> */
> if (fw_dump.reserve_bootvar)
> return fw_dump.reserve_bootvar;
> + else
> + printk(KERN_INFO "fadump: calculating default boot size\n");
>
> /* divide by 20 to get 5% of value */
> size = memblock_end_of_DRAM() / 20;

The code already knows how to reserve 5% based on the size of the machine's
memory, as long as no commandline parameter is passed. So why can't we
just use that logic?

cheers