Commit-ID: 6061efb6ee6fc891498a23994a4d0a5e2a52c059 Gitweb: http://git.kernel.org/tip/6061efb6ee6fc891498a23994a4d0a5e2a52c059 Author: Andi Kleen <[email protected]> AuthorDate: Tue, 28 Mar 2017 23:26:05 -0700 Committer: Ingo Molnar <[email protected]> CommitDate: Fri, 31 Mar 2017 11:20:05 +0200
x86/fpu: Turn WARN_ON() in context switch into WARN_ON_FPU() copy_xregs_to_kernel checks if the alternatives have been already patched. This WARN_ON() is always executed in every context switch. All the other checks in fpu internal.h are WARN_ON_FPU(), but this one is plain WARN_ON(). I assume it was forgotten to switch it. So switch it to WARN_ON_FPU() too to avoid some unnecessary code in the context switch, and a potentially expensive cache line miss for the global variable. Signed-off-by: Andi Kleen <[email protected]> Cc: Thomas Gleixner <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]> --- arch/x86/include/asm/fpu/internal.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/include/asm/fpu/internal.h b/arch/x86/include/asm/fpu/internal.h index bbee00aa..8044dc1 100644 --- a/arch/x86/include/asm/fpu/internal.h +++ b/arch/x86/include/asm/fpu/internal.h @@ -350,7 +350,7 @@ static inline void copy_xregs_to_kernel(struct xregs_state *xstate) u32 hmask = mask >> 32; int err; - WARN_ON(!alternatives_patched); + WARN_ON_FPU(!alternatives_patched); XSTATE_XSAVE(xstate, lmask, hmask, err);
