x86/cpufeature: Add helper macro for mask check macros
BugLink: https://bugs.launchpad.net/bugs/1790620 commit 8eda072e upstream Every time we add a word to our cpu features, we need to add something like this in two places: (((bit)>>5)==16 && (1UL<<((bit)&31) & REQUIRED_MASK16)) The trick is getting the "16" in this case in both places. I've now screwed this up twice, so as pennance, I've come up with this patch to keep me and other poor souls from doing the same. I also commented the logic behind the bit manipulation showcased above. Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave@sr71.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160629200110.1BA8949E@viggo.jf.intel.comSigned-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Srivatsa S. Bhat <srivatsa@csail.mit.edu> Reviewed-by: Matt Helsley (VMware) <matt.helsley@gmail.com> Reviewed-by: Alexey Makhalov <amakhalov@vmware.com> Reviewed-by: Bo Gan <ganb@vmware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Stefan Bader <stefan.bader@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
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