I am not very clear Why floating point support in the Kernel should be avoided ?
We want our DSP algorithm to run at the boot time and since kernel thread having higher priority , i assume that it would be faster than user application. If i really have to speed up my application execution what mechanism will you suggest me to try ? After using Hardware VFP support also i am still laging the timing requirement by 800 ms in my case ---- Misbah <>< Laurent Pinchart-4 wrote: > > On Friday 01 August 2008, Misbah khan wrote: >> >> Hi all, >> >> I have a DSP algorithm which i am running in the application even after >> enabling the VFP support it is taking a lot of time to get executed hence >> >> I want to transform the same into the driver insted of an user >> application. >> Can anybody suggest whether doing the same could be a better solution and >> what could be the chalenges that i have to face by implimenting such >> floating point support in the driver. >> >> Is there a way in the application itself to make it execute faster. > > Floating-point in the kernel should be avoided. FPU state save/restore > operations are costly and are not performed by the kernel when switching > from userspace to kernelspace context. You will have to protect > floating-point sections with kernel_fpu_begin/kernel_fpu_end which, if I'm > not mistaken, disables preemption. That's probably not something you want > to do. Why would the same code run faster in kernelspace then userspace ? > > -- > Laurent Pinchart > CSE Semaphore Belgium > > Chaussee de Bruxelles, 732A > B-1410 Waterloo > Belgium > > T +32 (2) 387 42 59 > F +32 (2) 387 42 75 > > > _______________________________________________ > Linuxppc-embedded mailing list > [email protected] > https://ozlabs.org/mailman/listinfo/linuxppc-embedded > -- View this message in context: http://www.nabble.com/floating-point-support-in-the-driver.-tp18772109p18772952.html Sent from the linuxppc-embedded mailing list archive at Nabble.com. _______________________________________________ Linuxppc-embedded mailing list [email protected] https://ozlabs.org/mailman/listinfo/linuxppc-embedded
