| From a1fbd7ef1da02f334ff72c52cb11116164649067 Mon Sep 17 00:00:00 2001 |
| From: Khem Raj <raj.khem@gmail.com> |
| Date: Thu, 31 Dec 2015 14:35:35 -0800 |
| Subject: [PATCH] nativesdk-glibc: Allow 64 bit atomics for x86 |
| |
| The fix consist of allowing 64bit atomic ops for x86. |
| This should be safe for i586 and newer CPUs. |
| It also makes the synchronization more efficient. |
| |
| Upstream-Status: Inappropriate [OE-Specific] |
| |
| Signed-off-by: Juro Bystricky <juro.bystricky@intel.com> |
| Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org> |
| Signed-off-by: Khem Raj <raj.khem@gmail.com> |
| --- |
| sysdeps/x86/atomic-machine.h | 7 +------ |
| 1 file changed, 1 insertion(+), 6 deletions(-) |
| |
| diff --git a/sysdeps/x86/atomic-machine.h b/sysdeps/x86/atomic-machine.h |
| index 2692d94a92..9d39bfdbd5 100644 |
| --- a/sysdeps/x86/atomic-machine.h |
| +++ b/sysdeps/x86/atomic-machine.h |
| @@ -52,19 +52,14 @@ typedef uintmax_t uatomic_max_t; |
| #define LOCK_PREFIX "lock;" |
| |
| #define USE_ATOMIC_COMPILER_BUILTINS 1 |
| +# define __HAVE_64B_ATOMICS 1 |
| |
| #ifdef __x86_64__ |
| -# define __HAVE_64B_ATOMICS 1 |
| # define SP_REG "rsp" |
| # define SEG_REG "fs" |
| # define BR_CONSTRAINT "q" |
| # define IBR_CONSTRAINT "iq" |
| #else |
| -/* Since the Pentium, i386 CPUs have supported 64-bit atomics, but the |
| - i386 psABI supplement provides only 4-byte alignment for uint64_t |
| - inside structs, so it is currently not possible to use 64-bit |
| - atomics on this platform. */ |
| -# define __HAVE_64B_ATOMICS 0 |
| # define SP_REG "esp" |
| # define SEG_REG "gs" |
| # define BR_CONSTRAINT "r" |