Hi all, The GNU/kFreeBSD port of the GNU libc uses normal syscalls (each syscall is mapped to a function), while the GNU/Linux version only uses inline syscalls (each syscall is mapped to asm inline code). The difference mainly comes from the fact that the FreeBSD kernel is also using the architecture ABI convention for the syscalls, while the Linux kernel uses its own convention.
Starting with glibc 2.10, some code starts to work only if inline syscalls are used. I have submitted a patch upstream (GLIBC), but it has been rejected [1]. I plan to also submit it to EGLIBC, I do not know if it will be accepted, however I start to fear that non-inline syscalls support will be progressively removed. And some parts are deep inside ld.so, I am not sure we can fork that indefinitely, even in EGLIBC. So let's talk about switching GNU/kFreeBSD to inline syscalls. For amd64, I already have a patch for syscalls with 6 arguments or less (when the stack is not used), it should not be a problem to add the code to pass one more argument on the stack. I think it can bring a small gain in speed when the number of args is not too high (when the stack is not used), which is the majority of syscalls. For i386 the situation is more complex. We need to pass up to 8 arguments to a syscall (especially when passing 64-bit values in two arguments), which is exactly the number of registers we have on this CPU. And they should in fine all be passed on the stack. Does anyone has an idea of a technical solution (not gcc version dependent) to get this working on i386? Does anyone has an opinion to share about that? Cheers, Aurelien [1] http://sources.redhat.com/bugzilla/show_bug.cgi?id=10192 -- Aurelien Jarno GPG: 1024D/F1BCDB73 aurel...@aurel32.net http://www.aurel32.net -- To UNSUBSCRIBE, email to debian-bsd-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org
