Hi Peter I can get the gcda for the kernel loadable module now. Yes, the virtual file is with size 0 and I saw the file is empty with 'vi' command. But, it has data with 'cat' or 'hexdump' command. Thanks. On Mon, Aug 26, 2013 at 10:19 PM, Peter Oberparleiter <oberpar@xxxxxxxxxxxxxxxxxx> wrote: > On 26.08.2013 13:39, LF.Tan wrote: >> Hi all >> >> I am interested to enable Gcov on my platform (on a target board). I >> have tried to apply the 4 patches submitted by Frantisek Hrbata. But, >> the *.gcda is always empty. Note, I am using GCC 4.7.3. >> >> I have followed the steps in Documentation/gcov.txt. I've mounted the >> NFS filesystem and it has access to the kernel build directory on host >> machine.The path for the kernel source in host and target are same. >> >> Let said my kernel module is under drivers/misc, >> drivers/misc/module.ko. Turn on Gcov in drivers/misc/Makefile. >> >> 1. mount -t debugfs none /sys/kernel/debug/ >> 2. insmod <PATH>/module.ko >> 3. Perform some actions to excute code in module.ko >> 4. rmmod <PATH>/module.ko >> 5. Check /sys/kernel/debug/gcov/<PATH>/drivers/misc/. There is a soft >> link of module.gcno (I check the soft link is working), but >> module.gcda is empty. > > Are you sure they are empty? .gcda files report a file size of 0 as many > virtual files do, but you can read data from them nevertheless. You could > try running "cat" on them to copy their contents for example. > >> Any step is incorrect or missing? Or anyone know how to enable GCOV on >> target board? Please advice. >> I would like to enable GCOV in arch/ code as well. >> Thank you very much. > > -- > Peter Oberparleiter > Linux on System z Development - IBM Germany > -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
