Re: Using signals to communicate two Qemu processes
Passera, Pablo R wrote: Hi all, I am trying to communicate two VMs using a virtio driver. Once a data is moved to the driver I want to notify the other Qemu process that there is new data available in the buffer. I was thinking about using linux signals to synchronize both processes but when I register my SIGUSR1 handler in Qemu I am seeing an strange behavior. After starting the VM and Linux gets loaded, Qemu is receiving SIGUSR2 at a regular time period. Looking a little bit at the code I realize that signals are being used for other purposes in Qemu, however, SIGUSR1 is not used. Is it possible to use signals to synchronize these processes or should I think about using a different mechanism? Signals are messy. I recommend using a unix-domain socket for this. It should be possible to use signals, however you should take care to mask the signal in all threads except the once you want to be the handler. -- error compiling committee.c: too many arguments to function -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Using signals to communicate two Qemu processes
Dor Laor wrote: Passera, Pablo R wrote: Hi all, I am trying to communicate two VMs using a virtio driver. Once a data is moved to the driver I want to notify the other Qemu process that there is new data available in the buffer. I was thinking about using linux signals to synchronize both processes but when I register my SIGUSR1 handler in Qemu I am seeing an strange behavior. After starting the VM and Linux gets loaded, Qemu is receiving SIGUSR2 at a regular time period. Looking a little bit at the code I realize that signals are being used for other purposes in Qemu, however, SIGUSR1 is not used. Is it possible to use signals to synchronize these processes or should I think about using a different mechanism? SIGUSR2 is used as aio completion signal. You can use SIGUSR1 but you need to know what you're doing (some threads block signals). Better fit would be a pipe. Or even a unix domain socket. Regards, Anthony Liguori -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Using signals to communicate two Qemu processes
Passera, Pablo R wrote: Hi all, I am trying to communicate two VMs using a virtio driver. Once a data is moved to the driver I want to notify the other Qemu process that there is new data available in the buffer. I was thinking about using linux signals to synchronize both processes but when I register my SIGUSR1 handler in Qemu I am seeing an strange behavior. After starting the VM and Linux gets loaded, Qemu is receiving SIGUSR2 at a regular time period. Looking a little bit at the code I realize that signals are being used for other purposes in Qemu, however, SIGUSR1 is not used. Is it possible to use signals to synchronize these processes or should I think about using a different mechanism? SIGUSR2 is used as aio completion signal. You can use SIGUSR1 but you need to know what you're doing (some threads block signals). Better fit would be a pipe. The vcpu Thanks, Pablo Pássera Intel - Software Innovation Pathfinding Group Cordoba - Argentina Phone: +54 351 526 5611 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Using signals to communicate two Qemu processes
Hi all, I am trying to communicate two VMs using a virtio driver. Once a data is moved to the driver I want to notify the other Qemu process that there is new data available in the buffer. I was thinking about using linux signals to synchronize both processes but when I register my SIGUSR1 handler in Qemu I am seeing an strange behavior. After starting the VM and Linux gets loaded, Qemu is receiving SIGUSR2 at a regular time period. Looking a little bit at the code I realize that signals are being used for other purposes in Qemu, however, SIGUSR1 is not used. Is it possible to use signals to synchronize these processes or should I think about using a different mechanism? Thanks, Pablo Pássera Intel - Software Innovation Pathfinding Group Cordoba - Argentina Phone: +54 351 526 5611 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
