Am Donnerstag, 29. März 2018, 22:20:47 CEST schrieb Joel Fernandes: > Thanks a lot! I am wondering why the same compiler works when running > the test for a regular image. Maybe different compiler flags. Anyway > good to learn this. > > Also one more slightly OT question, why is UML only doing UP ? Is it > extremely hard to do SMP for UML?
Long story short, nobody implemented SMP so far. :-) Because SKAS3/0 we had a SMP implementation of TT mode. In terms of UML implementing SMP means having multiple threads that handle the userspace loop in arch/um/os-Linux/skas/process.c. We could also do a poor man's SMP implementation first, where only user processes run in parallel. IOW userspace() in arch/um/os-Linux/skas/process.c is still a single thread but it let's run up to N user space thread and only if the call into the kernel we degrade to UP. Adding SMP is not extremely hard but it requires a lot of re-work of the UML core and introduces tons of new issues. That said, volunteers are welcome! Thanks, //richard ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ User-mode-linux-devel mailing list User-mode-linux-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel
