From: Paolo 'Blaisorblade' Giarrusso <[EMAIL PROTECTED]>
CC: Charles P. Wright <[EMAIL PROTECTED]>

As a follow-up to "UML Support - Ptrace: adds the host SYSEMU support, for UML
and general usage" (i.e. uml-support-* in current mm).

Avoid unconditionally jumping to work_pending and code copying, just reuse the
already existing resume_userspace path.

About those patches, they should stay in -mm only for now - I expect to get
them reviewed.

One interesting note, from Charles P. Wright, suggested that the API is
improvable with no downsides for UML (except that it will have to support yet
another host API, since dropping support for the current API, for UML, is not
reasonable from users' point of view).

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <[EMAIL PROTECTED]>
---

 linux-2.6.git-paolo/arch/i386/kernel/entry.S |    8 +-------
 1 files changed, 1 insertion(+), 7 deletions(-)

diff -puN arch/i386/kernel/entry.S~sysemu-cleanup-speedup 
arch/i386/kernel/entry.S
--- linux-2.6.git/arch/i386/kernel/entry.S~sysemu-cleanup-speedup       
2005-07-31 20:03:19.000000000 +0200
+++ linux-2.6.git-paolo/arch/i386/kernel/entry.S        2005-07-31 
20:03:19.000000000 +0200
@@ -339,18 +339,12 @@ syscall_trace_entry:
        xorl %edx,%edx
        call do_syscall_trace
        cmpl $0, %eax
-       jne syscall_skip                # ret != 0 -> running under 
PTRACE_SYSEMU,
+       jne resume_userspace            # ret != 0 -> running under 
PTRACE_SYSEMU,
                                        # so must skip actual syscall
        movl ORIG_EAX(%esp), %eax
        cmpl $(nr_syscalls), %eax
        jnae syscall_call
        jmp syscall_exit
-syscall_skip:
-       cli                             # make sure we don't miss an interrupt
-                                       # setting need_resched or sigpending
-                                       # between sampling and the iret
-       movl TI_flags(%ebp), %ecx
-       jmp work_pending
 
        # perform syscall exit tracing
        ALIGN
_


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