| commit c8a44ca1203244e18be053bd90b6b6df88d93d67 |
| Author: Kevin Cernekee <cernekee@gmail.com> |
| Date: Wed Apr 13 19:34:46 2011 -0700 |
| |
| Cache AT_PLATFORM and AT_L1D_CACHESHAPE from auxvec |
| |
| Allow uClibc internal functions to make optimizations at runtime, based |
| on the CPU type or D$ line size retrieved from the auxiliary vector. |
| This would nominally be used for functions like memcpy(), on processors |
| that do not have an unprivileged instruction along the lines of "CPUID". |
| |
| Signed-off-by: Kevin Cernekee <cernekee@gmail.com> |
| |
| diff --git a/include/libc-internal.h b/include/libc-internal.h |
| index 3ac0b05..ef5ce59 100644 |
| --- a/include/libc-internal.h |
| +++ b/include/libc-internal.h |
| @@ -65,6 +65,10 @@ libc_hidden_proto(__glibc_strerror_r) |
| /* internal access to program name */ |
| extern const char *__uclibc_progname attribute_hidden; |
| |
| +/* internal access to auxvec AT_PLATFORM, cache info */ |
| +extern const char *__auxv_platform attribute_hidden; |
| +extern int __auxv_l1d_cacheshape attribute_hidden; |
| + |
| # ifdef __UCLIBC_HAS_FORTIFY__ |
| extern void __chk_fail(void) attribute_noreturn; |
| libc_hidden_proto(__chk_fail) |
| diff --git a/libc/misc/internals/__uClibc_main.c b/libc/misc/internals/__uClibc_main.c |
| index 315365a..bc2e253 100644 |
| --- a/libc/misc/internals/__uClibc_main.c |
| +++ b/libc/misc/internals/__uClibc_main.c |
| @@ -30,6 +30,7 @@ |
| #include <fcntl.h> |
| #include <sys/stat.h> |
| #include <sys/sysmacros.h> |
| +#include <libc-internal.h> |
| #ifdef __UCLIBC_HAS_THREADS_NATIVE__ |
| #include <errno.h> |
| #include <pthread-functions.h> |
| @@ -156,6 +157,12 @@ weak_alias (program_invocation_short_name, __progname) |
| weak_alias (program_invocation_name, __progname_full) |
| #endif |
| |
| +/* Highest numbered auxvec entry to copy into auxvt[] */ |
| +#define AT_MAX AT_L3_CACHESHAPE |
| + |
| +attribute_hidden const char *__auxv_platform = NULL; |
| +attribute_hidden int __auxv_l1d_cacheshape = 0; |
| + |
| /* |
| * Declare the __environ global variable and create a weak alias environ. |
| * This must be initialized; we cannot have a weak alias into bss. |
| @@ -321,7 +328,7 @@ void __uClibc_main(int (*main)(int, char **, char **), int argc, |
| { |
| #ifndef __ARCH_HAS_NO_LDSO__ |
| unsigned long *aux_dat; |
| - ElfW(auxv_t) auxvt[AT_EGID + 1]; |
| + ElfW(auxv_t) auxvt[AT_MAX + 1]; |
| #endif |
| |
| #ifdef __UCLIBC_HAS_THREADS_NATIVE__ |
| @@ -355,7 +362,7 @@ void __uClibc_main(int (*main)(int, char **, char **), int argc, |
| aux_dat++; |
| while (*aux_dat) { |
| ElfW(auxv_t) *auxv_entry = (ElfW(auxv_t) *) aux_dat; |
| - if (auxv_entry->a_type <= AT_EGID) { |
| + if (auxv_entry->a_type <= AT_MAX) { |
| memcpy(&(auxvt[auxv_entry->a_type]), auxv_entry, sizeof(ElfW(auxv_t))); |
| } |
| aux_dat += 2; |
| @@ -376,6 +383,8 @@ void __uClibc_main(int (*main)(int, char **, char **), int argc, |
| #ifndef __ARCH_HAS_NO_LDSO__ |
| /* Make certain getpagesize() gives the correct answer */ |
| __pagesize = (auxvt[AT_PAGESZ].a_un.a_val)? auxvt[AT_PAGESZ].a_un.a_val : PAGE_SIZE; |
| + __auxv_platform = (char *)auxvt[AT_PLATFORM].a_un.a_val; |
| + __auxv_l1d_cacheshape = (int)auxvt[AT_L1D_CACHESHAPE].a_un.a_val; |
| |
| /* Prevent starting SUID binaries where the stdin. stdout, and |
| * stderr file descriptors are not already opened. */ |
