When cpuidle_idle_call() return 0, it shows that linux system is using idle framwork driver. Now, local irq has already been enabled in cpuidle_idle_call(). So, it need not enable local irq again, when return 0.
The code is introduced by commit: 97a5b81fa4d3a11dcdf224befc577f2e0abadc0b ("x86: Fix idle consolidation fallout") In that defect, it does not use idle framework driver, just call amd_e400_idle(). That problem is that amd_e400_idle() does not enable irq. Signed-off-by: Li Wang <li.w...@windriver.com> --- arch/x86/kernel/process.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c index 83369e5..cb55ee4 100644 --- a/arch/x86/kernel/process.c +++ b/arch/x86/kernel/process.c @@ -300,8 +300,6 @@ void arch_cpu_idle(void) { if (cpuidle_idle_call()) x86_idle(); - else - local_irq_enable(); } /* -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/