Hi, I am trying to apply the preempt_rt patches[2] in order to test the realtime performance of native code on an android device in a study project. The device I have for testing is the Galaxy Nexus.
People here seem to have managed to do that with a Xoom[1]. My starting point was the kernel of the current official (4.2.2) Android release (android-omap-tuna-3.0-jb-mr1.1). According to the version string it is based on linux 3.0.31, so I tried to patch it with the corresponding rt-patchset. Except for a few rejects that went fine. Most of them I could get fixed manually. My problem atm is that there seem to be quite some backports from newer (3.3/3.4?) kernels, especially for the file "include/linux/plist.h" and "kernel/rtmutex.c" which change some function-declarations. Today I managed to compile the kernel with the "CONFIG_PREEMPT_BASIC" option set, but when I try to boot the phone it gets stuck during the Google-bootscreen. It does not show up as an adb device, so I can't get any output from the device. For me the question is, how much of the Kernel is actually still 3.0.31, maybe it would be more suitable to use the rt_patches for more recent Linux-kernels? I was also thinking about trying to patch the kernel the GNex was released with, because this one may be closer to the original Linux kernel (I checked, plist.h and rtmutex.c are not the original ones as well)? Maybe someone else has a better idea what to test or where to read, because I am not overly familiar with all the different subbranches and development trees of Android yet. Any help or suggestions would be greatly appreciated. [1] http://www.linuxtag.org/2012/fileadmin/www.linuxtag.org/slides/Gernot%20Hillier%20+%20Wolfgang%20Mauerer%20+%20Jan%20Sawallisch%20-%20Android_%20real-time%20for%20the%20rest%20of%20us.p416.pdf [2] https://rt.wiki.kernel.org/index.php/CONFIG_PREEMPT_RT_Patch Best regards, Jan -- -- unsubscribe: android-kernel+unsubscr...@googlegroups.com website: http://groups.google.com/group/android-kernel --- You received this message because you are subscribed to the Google Groups "Android Linux Kernel Development" group. To unsubscribe from this group and stop receiving emails from it, send an email to android-kernel+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
