Use single instruction for find largest set bit on x86_64.
[Updated by Jan Beulich to fix wrong asm constraints in original
patch -AK]
Cc: jbeulich@novell.com
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch eliminates the GCC4 warning on the x86_64 platform:
kernel/sched.c:1824: warning: control may reach end of non-void function
'sched_find_first_bit' being inlined.
The change follows the lead of others, i.e. it is guaranteed that at least
one of b[0], b[1], or b[2] will have a bit set and evaluate to true. That
being said, GCC4.0.0 notices that the code flow does not return anything if
b[0], b[1] and b[2] are not true. Since we know better, if it's not b[0] or
b[1], it has to be b[2].
Signed-off-by: Jesse Millan <jessem@cs.pdx.edu>
Signed-off-by: Domen Puncer <domen@coderock.org>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch adds in the necessary support for sparsemem such that x86-64
kernels may use sparsemem as an alternative to discontigmem for NUMA
kernels. Note that this does no preclude one from continuing to build NUMA
kernels using discontigmem, but merely allows the option to build NUMA
kernels with sparsemem.
Interestingly, the use of sparsemem in lieu of discontigmem in NUMA kernels
results in reduced text size for otherwise equivalent kernels as shown in
the example builds below:
text data bss dec hex filename
2371036 765884 1237108 4374028 42be0c vmlinux.discontig
2366549 776484 1302772 4445805 43d66d vmlinux.sparse
Signed-off-by: Matt Tolentino <matthew.e.tolentino@intel.com>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Stephen Hemminger