Re: Question on hugepages_supported()
From: Aneesh Kumar K.V <hidden>
Date: 2017-08-02 07:29:24
Christophe LEROY [off-list ref] writes:
In include/linux/hugetlb.h, we find the following statement #ifndef hugepages_supported /* * Some platform decide whether they support huge pages at boot * time. Some of them, such as powerpc, set HPAGE_SHIFT to 0 * when there is no such support */ #define hugepages_supported() (HPAGE_SHIFT != 0) #endif But in arch/powerpc/include/asm/page.h we find: #ifdef CONFIG_HUGETLB_PAGE extern unsigned int HPAGE_SHIFT; #else #define HPAGE_SHIFT PAGE_SHIFT #endif Is that correct ? SHouldn't HPAGE_SHIFT be defined to 0 when CONFIG_HUGETLB_PAGE is not defined ?
But then hugepages_supported() is only defined if HUGETLB_PAGE is enabled. So yes we can possibly say HPAGE_SHIFT = 0 if HUGETLB is disabled, I am not sure it has any impact with the current code ? -aneesh