From ea180bb3797ed4e976adccfba7d09c154d3244d1 Mon Sep 17 00:00:00 2001 From: Brooks Davis Date: Mon, 27 Nov 2023 17:06:25 +0000 Subject: [PATCH] getpagesize(3): drop support for non-ELF kernels AT_PAGESZ was introduced with ELF support in 1996 (commit e1743d02cd14069f69a50bb8a6c626c1c6f47ddd) so we can safely count on being able to use it to get our page size via elf_aux_info(). As such we don't need a fallback sysctl query. Save a few bytes of bss by dropping caching as elf_aux_info() runs in constant time for a given query. Reviewed by: kevans, imp, emaste Sponsored by: DARPA Differential Revision: https://reviews.freebsd.org/D42708 --- lib/libc/gen/getpagesize.c | 28 ++++------------------------ 1 file changed, 4 insertions(+), 24 deletions(-) diff --git a/lib/libc/gen/getpagesize.c b/lib/libc/gen/getpagesize.c index 5fe9a965385..23d2c6ea5ed 100644 --- a/lib/libc/gen/getpagesize.c +++ b/lib/libc/gen/getpagesize.c @@ -30,18 +30,11 @@ */ #include -#include - -#include -#include -#include +#include #include "libc_private.h" /* - * This is unlikely to change over the running time of any - * program, so we cache the result to save some syscalls. - * * NB: This function may be called from malloc(3) at initialization * NB: so must not result in a malloc(3) related call! */ @@ -49,23 +42,10 @@ int getpagesize(void) { - int mib[2]; - static int value; - size_t size; - int error; + int value; - if (value != 0) - return (value); - - error = _elf_aux_info(AT_PAGESZ, &value, sizeof(value)); - if (error == 0 && value != 0) - return (value); - - mib[0] = CTL_HW; - mib[1] = HW_PAGESIZE; - size = sizeof value; - if (sysctl(mib, nitems(mib), &value, &size, NULL, 0) == -1) - return (PAGE_SIZE); + if (_elf_aux_info(AT_PAGESZ, &value, sizeof(value)) != 0) + value = PAGE_SIZE; return (value); }