From 495ab9c045e1b0e5c82951b762257fe1c9d81564 Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Mon, 26 Jun 2006 13:59:11 +0200 Subject: [PATCH] i386/x86-64/ia64: Move polling flag into thread_info_status During some profiling I noticed that default_idle causes a lot of memory traffic. I think that is caused by the atomic operations to clear/set the polling flag in thread_info. There is actually no reason to make this atomic - only the idle thread does it to itself, other CPUs only read it. So I moved it into ti->status. Converted i386/x86-64/ia64 for now because that was the easiest way to fix ACPI which also manipulates these flags in its idle function. Cc: Nick Piggin Cc: Tony Luck Cc: Len Brown Signed-off-by: Andi Kleen Signed-off-by: Linus Torvalds --- arch/i386/kernel/apm.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'arch/i386/kernel/apm.c') diff --git a/arch/i386/kernel/apm.c b/arch/i386/kernel/apm.c index 9e819eb6822..7c5729d1fd0 100644 --- a/arch/i386/kernel/apm.c +++ b/arch/i386/kernel/apm.c @@ -764,9 +764,9 @@ static int apm_do_idle(void) int idled = 0; int polling; - polling = test_thread_flag(TIF_POLLING_NRFLAG); + polling = !!(current_thread_info()->status & TS_POLLING); if (polling) { - clear_thread_flag(TIF_POLLING_NRFLAG); + current_thread_info()->status &= ~TS_POLLING; smp_mb__after_clear_bit(); } if (!need_resched()) { @@ -774,7 +774,7 @@ static int apm_do_idle(void) ret = apm_bios_call_simple(APM_FUNC_IDLE, 0, 0, &eax); } if (polling) - set_thread_flag(TIF_POLLING_NRFLAG); + current_thread_info()->status |= TS_POLLING; if (!idled) return 0; -- cgit v1.2.3