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Date: Thu, 21 May 2009 01:17:59 +0200 From: Alexander van Heukelum <heukelum@...tmail.fm> To: Ingo Molnar <mingo@...e.hu>, LKML <linux-kernel@...r.kernel.org> Cc: Jan Beulich <JBeulich@...ell.com>, "H. Peter Anvin" <hpa@...or.com>, Cyrill Gorcunov <gorcunov@...il.com>, Alexander van Heukelum <heukelum@...tmail.fm> Subject: [PATCH] i386, entry_32: get rid of resume_userspace_sig define resume_userspace_sig is defined to check_userspace or resume_userspace depending on CONFIG_VM86. It's used only two times, and once inside code conditionally compiled depending on CONFIG_VM86. Duplicating two trivial lines leaves a single #ifdef/#else block and removes the need for redefining labels. Inverting a branch and getting rid of some real code duplication removes a few bytes from the object file. before, CONFIG_VM86=y --------------------- c1008749 <work_notifysig>: c1008749: f7 44 24 38 00 00 02 testl $0x20000,0x38(%esp) c1008750: 00 c1008751: 89 e0 mov %esp,%eax c1008753: 75 0f jne c1008764 <work_notifysig_v86> c1008755: 31 d2 xor %edx,%edx c1008757: e8 34 f0 ff ff call c1007790 <do_notify_resume> c100875c: e9 89 fd ff ff jmp c10084ea <check_userspace> c1008761: 8d 76 00 lea 0x0(%esi),%esi c1008764 <work_notifysig_v86>: c1008764: 51 push %ecx c1008765: e8 76 69 01 00 call c101f0e0 <save_v86_state> c100876a: 59 pop %ecx c100876b: 89 c4 mov %eax,%esp c100876d: 31 d2 xor %edx,%edx c100876f: e8 1c f0 ff ff call c1007790 <do_notify_resume> c1008774: e9 71 fd ff ff jmp c10084ea <check_userspace> after, CONFIG_VM86=y -------------------- c1008749 <work_notifysig>: c1008749: f7 44 24 38 00 00 02 testl $0x20000,0x38(%esp) c1008750: 00 c1008751: 89 e0 mov %esp,%eax c1008753: 74 09 je c100875e <no_work_notifysig_v86> c1008755: 51 push %ecx c1008756: e8 65 69 01 00 call c101f0c0 <save_v86_state> c100875b: 59 pop %ecx c100875c: 89 c4 mov %eax,%esp c100875e <no_work_notifysig_v86>: c100875e: 31 d2 xor %edx,%edx c1008760: e8 2b f0 ff ff call c1007790 <do_notify_resume> c1008765: e9 80 fd ff ff jmp c10084ea <check_userspace> before, CONFIG_VM86=n --------------------- c1008729 <work_notifysig>: c1008729: 89 e0 mov %esp,%eax c100872b: 31 d2 xor %edx,%edx c100872d: e8 3e f0 ff ff call c1007770 <do_notify_resume> c1008732: e9 a9 fd ff ff jmp c10084e0 <resume_userspace> after, CONFIG_VM86=n (i.e., no change) -------------------------------------- c1008729: 89 e0 mov %esp,%eax c100872b: 31 d2 xor %edx,%edx c100872d: e8 3e f0 ff ff call c1007770 <do_notify_resume> c1008732: e9 a9 fd ff ff jmp c10084e0 <resume_userspace> Signed-off-by: Alexander van Heukelum <heukelum@...tmail.fm> --- arch/x86/kernel/entry_32.S | 22 +++++++--------------- 1 files changed, 7 insertions(+), 15 deletions(-) diff --git a/arch/x86/kernel/entry_32.S b/arch/x86/kernel/entry_32.S index c929add..314563e 100644 --- a/arch/x86/kernel/entry_32.S +++ b/arch/x86/kernel/entry_32.S @@ -96,12 +96,6 @@ #endif .endm -#ifdef CONFIG_VM86 -#define resume_userspace_sig check_userspace -#else -#define resume_userspace_sig resume_userspace -#endif - /* * User gs save/restore * @@ -634,26 +628,24 @@ work_notifysig: # deal with pending signals and #ifdef CONFIG_VM86 testl $X86_EFLAGS_VM, PT_EFLAGS(%esp) movl %esp, %eax - jne work_notifysig_v86 # returning to kernel-space or + je no_work_notifysig_v86 # returning to kernel-space or # vm86-space - xorl %edx, %edx - call do_notify_resume - jmp resume_userspace_sig - - ALIGN -work_notifysig_v86: pushl %ecx # save ti_flags for do_notify_resume CFI_ADJUST_CFA_OFFSET 4 call save_v86_state # %eax contains pt_regs pointer popl %ecx CFI_ADJUST_CFA_OFFSET -4 movl %eax, %esp +no_work_notifysig_v86: + xorl %edx, %edx # %eax contains pt_regs pointer + call do_notify_resume + jmp check_userspace #else movl %esp, %eax -#endif xorl %edx, %edx call do_notify_resume - jmp resume_userspace_sig + jmp resume_userspace +#endif END(work_pending) # perform syscall exit tracing -- 1.6.0.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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