| Date | Tue, 22 Apr 2014 16:09:46 +0800 | Subject | Re: [PATCH 09/28] nios2: Page table management | From | Ley Foon Tan <> |
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Hi
On Sun, Apr 20, 2014 at 12:05 AM, Pavel Machek <pavel@denx.de> wrote:
>> +static void pgd_init(pgd_t *pgd) >> +{ >> + unsigned long *p = (unsigned long *) pgd; >> + int i; >> + >> + for (i = 0; i < USER_PTRS_PER_PGD; i += 8) { >> + p[i + 0] = (unsigned long) invalid_pte_table; >> + p[i + 1] = (unsigned long) invalid_pte_table; >> + p[i + 2] = (unsigned long) invalid_pte_table; >> + p[i + 3] = (unsigned long) invalid_pte_table; >> + p[i + 4] = (unsigned long) invalid_pte_table; >> + p[i + 5] = (unsigned long) invalid_pte_table; >> + p[i + 6] = (unsigned long) invalid_pte_table; >> + p[i + 7] = (unsigned long) invalid_pte_table; >> + } > > Umm. Manual loop unrolling. Does it really improve performance? Is the > code hot enough to warrant the uglyness? We can use the memset here because invalid_pte_table is full 32 bit value. BTW, arch for score and mips have the similar implementation as well.
Regards
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