* Submissions for 2.4.19-pre [x86 Syscall Optimizations (Alexander Khripin)]
@ 2002-02-26 2:07 Michael Cohen
2002-02-26 2:34 ` Alan Cox
0 siblings, 1 reply; 6+ messages in thread
From: Michael Cohen @ 2002-02-26 2:07 UTC (permalink / raw)
To: linux-kernel; +Cc: marcelo
This is the sixth of several mails containing patches to be included in 2.4.19. Some are worthy of dicussion prior to inclusion and have been marked as such. The majority of these patches were found on lkml; the remaining ones have URLs listed.
This one originated on lkml.
------
Michael Cohen
OhDarn.net
--- linux-virgin/arch/i386/kernel/entry.S Sun Jan 13 17:54:54 2002
+++ linux-wli/arch/i386/kernel/entry.S Sun Jan 13 18:09:36 2002
@@ -111,9 +111,9 @@
pushl %edi; \
pushl %esi; \
pushl %edx; \
+ movl $(__KERNEL_DS),%edx; \
pushl %ecx; \
pushl %ebx; \
- movl $(__KERNEL_DS),%edx; \
movl %edx,%ds; \
movl %edx,%es;
@@ -161,13 +161,13 @@
movl EFLAGS(%esp),%ecx # and this is cs..
movl %eax,EFLAGS(%esp) #
movl %edx,EIP(%esp) # Now we move them to their "normal" places
- movl %ecx,CS(%esp) #
movl %esp,%ebx
+ movl %ecx,CS(%esp) #
pushl %ebx
andl $-8192,%ebx # GET_CURRENT
movl exec_domain(%ebx),%edx # Get the execution domain
- movl 4(%edx),%edx # Get the lcall7 handler for the domain
pushl $0x7
+ movl 4(%edx),%edx # Get the lcall7 handler for the domain
call *%edx
addl $4, %esp
popl %eax
@@ -182,13 +182,13 @@
movl EFLAGS(%esp),%ecx # and this is cs..
movl %eax,EFLAGS(%esp) #
movl %edx,EIP(%esp) # Now we move them to their "normal" places
- movl %ecx,CS(%esp) #
movl %esp,%ebx
+ movl %ecx,CS(%esp) #
pushl %ebx
andl $-8192,%ebx # GET_CURRENT
movl exec_domain(%ebx),%edx # Get the execution domain
- movl 4(%edx),%edx # Get the lcall7 handler for the domain
pushl $0x27
+ movl 4(%edx),%edx # Get the lcall7 handler for the domain
call *%edx
addl $4, %esp
popl %eax
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: Submissions for 2.4.19-pre [x86 Syscall Optimizations (Alexander Khripin)]
2002-02-26 2:07 Submissions for 2.4.19-pre [x86 Syscall Optimizations (Alexander Khripin)] Michael Cohen
@ 2002-02-26 2:34 ` Alan Cox
2002-02-26 2:32 ` Michael Cohen
0 siblings, 1 reply; 6+ messages in thread
From: Alan Cox @ 2002-02-26 2:34 UTC (permalink / raw)
To: Michael Cohen; +Cc: linux-kernel, marcelo
> This is the sixth of several mails containing patches to be included in 2.4.19. Some are worthy of dicussion prior to inclusion and have been marked as such. The majority of these patches were found on lkml; the remaining ones have URLs listed.
> This one originated on lkml.
Credit for the originator and an explanation would be helpful
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: Submissions for 2.4.19-pre [x86 Syscall Optimizations (Alexander Khripin)]
2002-02-26 2:34 ` Alan Cox
@ 2002-02-26 2:32 ` Michael Cohen
2002-02-26 3:19 ` Robert Love
0 siblings, 1 reply; 6+ messages in thread
From: Michael Cohen @ 2002-02-26 2:32 UTC (permalink / raw)
To: Alan Cox; +Cc: linux-kernel, marcelo
On Tue, 26 Feb 2002 02:34:46 +0000 (GMT)
Alan Cox <alan@lxorguk.ukuu.org.uk> wrote:
> > This is the sixth of several mails containing patches to be included in 2.4.19. Some are worthy of dicussion prior to inclusion and have been marked as such. The majority of these patches were found on lkml; the remaining ones have URLs listed.
> > This one originated on lkml.
>
> Credit for the originator and an explanation would be helpful
See Subject ^^ Alexander Khripin. Looks to me like it improves latency quite a bit during syscalls. I'm unable to find the exact mail but I believe I was referred to this particular patch by someone on lkml.
------
Michael Cohen
OhDarn.net
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: Submissions for 2.4.19-pre [x86 Syscall Optimizations (Alexander Khripin)]
2002-02-26 2:32 ` Michael Cohen
@ 2002-02-26 3:19 ` Robert Love
2002-02-26 3:26 ` Michael Cohen
0 siblings, 1 reply; 6+ messages in thread
From: Robert Love @ 2002-02-26 3:19 UTC (permalink / raw)
To: Michael Cohen; +Cc: Alan Cox, linux-kernel, marcelo
On Mon, 2002-02-25 at 21:32, Michael Cohen wrote:
>
> Alan Cox <alan@lxorguk.ukuu.org.uk> wrote:
>
> > Credit for the originator and an explanation would be helpful
>
> See Subject ^^ Alexander Khripin. Looks to me like it improves latency
> quite a bit during syscalls. I'm unable to find the exact mail but I
> believe I was referred to this particular patch by someone on lkml.
Eh? The patch doesn't do anything but move movl ops around. I suspect
the intention may to eliminate datapath stalls, which may be a fine
micro-optimization, but I think we need some numbers first ...
Robert Love
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: Submissions for 2.4.19-pre [x86 Syscall Optimizations (Alexander Khripin)]
2002-02-26 3:19 ` Robert Love
@ 2002-02-26 3:26 ` Michael Cohen
2002-02-26 9:31 ` Alan Cox
0 siblings, 1 reply; 6+ messages in thread
From: Michael Cohen @ 2002-02-26 3:26 UTC (permalink / raw)
To: Robert Love; +Cc: alan, linux-kernel, marcelo
On 25 Feb 2002 22:19:17 -0500
Robert Love <rml@tech9.net> wrote:
> > See Subject ^^ Alexander Khripin. Looks to me like it improves latency
> > quite a bit during syscalls. I'm unable to find the exact mail but I
> > believe I was referred to this particular patch by someone on lkml.
>
> Eh? The patch doesn't do anything but move movl ops around. I suspect
> the intention may to eliminate datapath stalls, which may be a fine
> micro-optimization, but I think we need some numbers first ...
UNIXbench numbers on the way :)
------
Michael Cohen
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: Submissions for 2.4.19-pre [x86 Syscall Optimizations (Alexander Khripin)]
2002-02-26 3:26 ` Michael Cohen
@ 2002-02-26 9:31 ` Alan Cox
0 siblings, 0 replies; 6+ messages in thread
From: Alan Cox @ 2002-02-26 9:31 UTC (permalink / raw)
To: Michael Cohen; +Cc: Robert Love, alan, linux-kernel, marcelo
> > Eh? The patch doesn't do anything but move movl ops around. I suspect
> > the intention may to eliminate datapath stalls, which may be a fine
> > micro-optimization, but I think we need some numbers first ...
>
> UNIXbench numbers on the way :)
Remember to get them with more than one vendor and family of processors.
Quite a lot of proposed micro-optimisations turn out to be pessimisations
except for the processor of the original proposer 8(
^ permalink raw reply [flat|nested] 6+ messages in thread
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2002-02-26 2:07 Submissions for 2.4.19-pre [x86 Syscall Optimizations (Alexander Khripin)] Michael Cohen
2002-02-26 2:34 ` Alan Cox
2002-02-26 2:32 ` Michael Cohen
2002-02-26 3:19 ` Robert Love
2002-02-26 3:26 ` Michael Cohen
2002-02-26 9:31 ` Alan Cox
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