[Qemu-devel] How to speed up the CPU logging?
Hi, Guy, When I use *log cpu* or *log exec* in the system *-monitor stdio* mode, it's extremely slow(lose my mouse/keyboard control). I used a buffer instead of directly writing log to disk, but even slower. When I give a large memory (-m 4G) to VM, or set the process priority(chrt -f 99) of QEMU, the situation is the same. Any approach to speed up logging? (let me be able to control the VM when logging.) Thanks.
Re: [Qemu-devel] How to speed up the CPU logging?
Thanks for replying. Do you know any easy way to do that? On Sat, Jun 9, 2012 at 11:02 AM, Blue Swirl blauwir...@gmail.com wrote: On Sat, Jun 9, 2012 at 2:37 PM, Yue Chen ycyc...@gmail.com wrote: Hi, Guy, When I use log cpu or log exec in the system -monitor stdio mode, it's extremely slow(lose my mouse/keyboard control). I used a buffer instead of directly writing log to disk, but even slower. When I give a large memory (-m 4G) to VM, or set the process priority(chrt -f 99) of QEMU, the situation is the same. Any approach to speed up logging? (let me be able to control the VM when logging.) Thanks. The performance is slow because logging is text based and therefore there is a lot of processing and I/O. Log users should be converted to trace points which use binary data, that would be much faster and more efficient.
Re: [Qemu-devel] Any approach to log the file read/write (I/O data flow) like the -d in_asm option?
I'm doing something like a *simple and lightweight* REPLAY program out of QEMU, only including CPU, MEMORY, and DISK. I'm implementing it with a shadow CPU (register state), shadow memory(from *pmemsave*) and shadow * .img* file (disk). When I get the *log exec,op*(preferred) or *log exec,in_asm*instruction traces from monitor in whole-system emulation mode, the final step to replay read/write a file to/from the disk seems the *in/ins* and * out/outs* instructions(translated into a *CALL* instruction in Intermediate Representation of QEMU), which can set DMA and transfer data. But from the instruction traces, I don't know which location in the *.img*file (disk) has been accessed. (It's also hard to find out which file has been read/written in higher semantics.) Any easy approach to do this? Thanks so much. On Fri, Jun 1, 2012 at 4:09 AM, Stefan Hajnoczi stefa...@gmail.com wrote: On Fri, Jun 1, 2012 at 4:11 AM, Yue Chen ycyc...@gmail.com wrote: Any approach to log all the file read/write (I/O data flow) in order, together with the instruction traces in QEMU? Thanks. It sounds like you may be running a *-user target because softmmu (system emulation) has no knowledge of file I/O inside the guest. Please give more details of what you're trying to do if this is incorrect. It sounds like you want strace together with -d in_asm output. Have you seen linux-user/strace.c? Stefan
[Qemu-devel] Any approach to log the file read/write (I/O data flow) like the -d in_asm option?
Hi, Any approach to log all the file read/write (I/O data flow) in order, together with the instruction traces in QEMU? Thanks.
Re: [Qemu-devel] Lack of codes in logging
Do you know how to use that? When I use* log(-d) exec and log(-d) pcall*, the qemu.log is always empty. On Mon, May 28, 2012 at 10:47 PM, 陳韋任 (Wei-Ren Chen) che...@iis.sinica.edu.tw wrote: On Mon, May 28, 2012 at 10:37:47PM -0400, Yue Chen wrote: What's the helper function? Thanks. How QEMU translation works is as below, guest binary - TCG IR - host binary To express complicated operations is not easy for TCG IR. Therefore, you can write normal C function (helper_function), then use TCG IR call to call that C function (call helper_function). But I note what you are talking about is in_asm, not op, so Peter should be right. Try -d exec instead. Regards, chenwj -- Wei-Ren Chen (陳韋任) Computer Systems Lab, Institute of Information Science, Academia Sinica, Taiwan (R.O.C.) Tel:886-2-2788-3799 #1667 Homepage: http://people.cs.nctu.edu.tw/~chenwj
[Qemu-devel] To run (replay) the intermediate micro-ops directly
Hi, Does anyone know, how to run(replay) the intermediate micro-ops directly? For example, I have traced some micro-op instructions, and want to see what happens with these instructions(after being translated into host code and then run). Probably with Graphic User Interface. Any approach to do this in QEMU? Thanks.
Re: [Qemu-devel] Debug single program in QEMU
Hi, thanks again for your reply. It seems that, from the instruction log, we can find out *which instructions belong to which process(task)* according to CR3 register. 2012/3/15 陳韋任 che...@iis.sinica.edu.tw O.K., then. You must specify which mode you're running, user mode or system mode? User mode shouldn't have the issue you described. For system mode, I have no good idea on how to track a specific program running on the guest OS. On Thu, Mar 15, 2012 at 09:40:48AM -0400, Yue Chen wrote: But it is hard to localize a specific program instead of lots of logs. On Mar 15, 2012 4:14 AM, 陳韋任 che...@iis.sinica.edu.tw wrote: On Thu, Mar 15, 2012 at 01:26:44PM +0700, Mulyadi Santosa wrote: On Thu, Mar 15, 2012 at 09:12, Yue Chen ycyc...@gmail.com wrote: Hi!~ Now I'd like to see what the micro-ops (intermediate operations generated by TCG) of a single Linux or Windows program, any approach to do this under QEMU? Thanks. are you referring to you Qemu system emulation or Qemu user mode? Does that matter? I think -d op should be enough, right? Regards, chenwj -- Wei-Ren Chen (陳韋任) Computer Systems Lab, Institute of Information Science, Academia Sinica, Taiwan (R.O.C.) Tel:886-2-2788-3799 #1667 Homepage: http://people.cs.nctu.edu.tw/~chenwj
Re: [Qemu-devel] Debug single program in QEMU
Hi, Could you tell me what kind of programs can be emulated in user-mode of QEMU ? It seems that only limited programs can be emulated in user-mode, like /bin/ls, and with warning. A lot of other programs cannot be emulated, like GUI programs, browser, etc. Additionally, why so many instructions come out when I use -d in_asm to log? It's hard to find the real instructions of that single program... Thanks. 2012/3/15 陳韋任 che...@iis.sinica.edu.tw http://qemu.weilnetz.de/qemu-doc.html#QEMU-User-space-emulator On Thu, Mar 15, 2012 at 10:42:02PM -0400, Yue Chen wrote: So how to run a Windows program or Linux program under user mode ? I cannot find useful documentations. Many thanks. -- Wei-Ren Chen (陳韋任) Computer Systems Lab, Institute of Information Science, Academia Sinica, Taiwan (R.O.C.) Tel:886-2-2788-3799 #1667 Homepage: http://people.cs.nctu.edu.tw/~chenwj
Re: [Qemu-devel] Debug single program in QEMU
But it is hard to localize a specific program instead of lots of logs. On Mar 15, 2012 4:14 AM, 陳韋任 che...@iis.sinica.edu.tw wrote: On Thu, Mar 15, 2012 at 01:26:44PM +0700, Mulyadi Santosa wrote: On Thu, Mar 15, 2012 at 09:12, Yue Chen ycyc...@gmail.com wrote: Hi!~ Now I'd like to see what the micro-ops (intermediate operations generated by TCG) of a single Linux or Windows program, any approach to do this under QEMU? Thanks. are you referring to you Qemu system emulation or Qemu user mode? Does that matter? I think -d op should be enough, right? Regards, chenwj -- Wei-Ren Chen (陳韋任) Computer Systems Lab, Institute of Information Science, Academia Sinica, Taiwan (R.O.C.) Tel:886-2-2788-3799 #1667 Homepage: http://people.cs.nctu.edu.tw/~chenwj
Re: [Qemu-devel] Debug single program in QEMU
So how to run a Windows program or Linux program under user mode ? I cannot find useful documentations. Many thanks. 2012/3/15 陳韋任 che...@iis.sinica.edu.tw O.K., then. You must specify which mode you're running, user mode or system mode? User mode shouldn't have the issue you described. For system mode, I have no good idea on how to track a specific program running on the guest OS. On Thu, Mar 15, 2012 at 09:40:48AM -0400, Yue Chen wrote: But it is hard to localize a specific program instead of lots of logs. On Mar 15, 2012 4:14 AM, 陳韋任 che...@iis.sinica.edu.tw wrote: On Thu, Mar 15, 2012 at 01:26:44PM +0700, Mulyadi Santosa wrote: On Thu, Mar 15, 2012 at 09:12, Yue Chen ycyc...@gmail.com wrote: Hi!~ Now I'd like to see what the micro-ops (intermediate operations generated by TCG) of a single Linux or Windows program, any approach to do this under QEMU? Thanks. are you referring to you Qemu system emulation or Qemu user mode? Does that matter? I think -d op should be enough, right? Regards, chenwj -- Wei-Ren Chen (陳韋任) Computer Systems Lab, Institute of Information Science, Academia Sinica, Taiwan (R.O.C.) Tel:886-2-2788-3799 #1667 Homepage: http://people.cs.nctu.edu.tw/~chenwj
[Qemu-devel] Debug single program in QEMU
Hi!~ Now I'd like to see what the micro-ops (intermediate operations generated by TCG) of a single Linux or Windows program, any approach to do this under QEMU? Thanks.
Re: [Qemu-devel] How to trace all the guest OS instructions and the micro-ops
Thanks a lot. So any approach to get the dynamic or static whole memory information of the guest OS ? Not the memory of each process. Sorry for the confusion. I do use version 1.0.1. I mention not in 0.9.1 because someone has already implemented the dynamic tracing in 0.9.1, but not in the latest version. On Mon, Mar 12, 2012 at 2:20 AM, Chen Yufei cyfde...@gmail.com wrote: On Mon, Mar 12, 2012 at 5:43 AM, Mulyadi Santosa mulyadi.sant...@gmail.com wrote: Hi On Sun, Mar 11, 2012 at 10:12, Yue Chen ycyc...@gmail.com wrote: I am doing some research based on the QEMU. Does anyone know how to get (trace) all the instructions of the guest OS, and get all the intermediate micro-ops ? (Not in the 0.9.1 version) QEMU has release version 1.0.1. Why are you still using 0.9.1? I believe it's -d option you're looking for. Please read qemu manual for further clarification and info. -d can only give a static view of what instruction is translated, but can't get a dynamic instruction execution trace. Additionally, how to get the whole memory or each process' memory data of the guest OS? you wanna do that simply from Qemu's monitor? I don't think that's doable...or at least easily. Qemu sees guest RAM like your physical RAM. It doesn't differentiate which pages belongs to which process. You need to hook or go straight inside the guest OS, maybe using gdb or other tool to get the core dump of those processes. I really appreciate your help. Hope it helps... -- regards, Mulyadi Santosa Freelance Linux trainer and consultant blog: the-hydra.blogspot.com training: mulyaditraining.blogspot.com -- Best regards, Chen Yufei
[Qemu-devel] How to trace all the guest OS instructions and the micro-ops
Hi! I am doing some research based on the QEMU. Does anyone know how to get (trace) all the instructions of the guest OS, and get all the intermediate micro-ops ? (Not in the 0.9.1 version) Additionally, how to get the whole memory or each process' memory data of the guest OS? I really appreciate your help.
