From: H. Peter Anvin Date: Thu, 10 Dec 2009 00:33:44 +0000 (-0800) Subject: x86-32: Avoid pipeline serialization in PTREGSCALL1 and 2 X-Git-Tag: firefly_0821_release~9833^2~3339^2~38^2~6 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=ce9119ad90b1caba550447bfcc0a21850558ca49;p=firefly-linux-kernel-4.4.55.git x86-32: Avoid pipeline serialization in PTREGSCALL1 and 2 In the PTREGSCALL1 and 2 macros, we can trivially avoid an unnecessary pipeline serialization, so do so. In PTREGSCALLS3 this is much less clear-cut since we have to push a new value to the stack. Leave it alone for now assuming it is as good as it is going to be; may want to check on Atom or another in-order x86 to see if we can do better. Signed-off-by: H. Peter Anvin Cc: Brian Gerst LKML-Reference: <1260403316-5679-2-git-send-email-brgerst@gmail.com> --- diff --git a/arch/x86/kernel/entry_32.S b/arch/x86/kernel/entry_32.S index 6492555d123d..cb12b9bfc9cc 100644 --- a/arch/x86/kernel/entry_32.S +++ b/arch/x86/kernel/entry_32.S @@ -735,15 +735,15 @@ ptregs_##name: \ ALIGN; \ ptregs_##name: \ leal 4(%esp),%edx; \ - movl PT_EBX(%edx),%eax; \ + movl (PT_EBX+4)(%esp),%eax; \ jmp sys_##name; #define PTREGSCALL2(name) \ ALIGN; \ ptregs_##name: \ leal 4(%esp),%ecx; \ - movl PT_ECX(%ecx),%edx; \ - movl PT_EBX(%ecx),%eax; \ + movl (PT_ECX+4)(%esp),%edx; \ + movl (PT_EBX+4)(%esp),%eax; \ jmp sys_##name; #define PTREGSCALL3(name) \