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  • Peter Zijlstra's avatar
    x86/debug: Implement __WARN() using UD0 · 9a93848f
    Peter Zijlstra authored
    
    
    By using "UD0" for WARN()s we remove the function call and its possible
    __FILE__ and __LINE__ immediate arguments from the instruction stream.
    
    Total image size will not change much, what we win in the instruction
    stream we'll lose because of the __bug_table entries. Still, saves on
    I$ footprint and the total image size does go down a bit.
    
          text    data       filename
      10702123    4530992    defconfig-build/vmlinux.orig
      10682460    4530992    defconfig-build/vmlinux.patched
    
    (UML didn't seem to use GENERIC_BUG at all, so remove it)
    
    Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
    Reviewed-by: default avatarJosh Poimboeuf <jpoimboe@redhat.com>
    Cc: Arjan van de Ven <arjan@linux.intel.com>
    Cc: Borislav Petkov <bp@alien8.de>
    Cc: Linus Torvalds <torvalds@linux-foundation.org>
    Cc: Peter Zijlstra <peterz@infradead.org>
    Cc: Richard Weinberger <richard.weinberger@gmail.com>
    Cc: Thomas Gleixner <tglx@linutronix.de>
    Cc: linux-kernel@vger.kernel.org
    Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
    9a93848f