x86 idle: remove 32-bit-only "no-hlt" parameter, hlt_works_ok flag

Remove 32-bit x86 a cmdline param "no-hlt",
and the cpuinfo_x86.hlt_works_ok that it sets.

If a user wants to avoid HLT, then "idle=poll"
is much more useful, as it avoids invocation of HLT
in idle, while "no-hlt" failed to do so.

Indeed, hlt_works_ok was consulted in only 3 places.

First, in /proc/cpuinfo where "hlt_bug yes"
would be printed if and only if the user booted
the system with "no-hlt" -- as there was no other code
to set that flag.

Second, check_hlt() would not invoke halt() if "no-hlt"
were on the cmdline.

Third, it was consulted in stop_this_cpu(), which is invoked
by native_machine_halt()/reboot_interrupt()/smp_stop_nmi_callback() --
all cases where the machine is being shutdown/reset.
The flag was not consulted in the more frequently invoked
play_dead()/hlt_play_dead() used in processor offline and suspend.

Since Linux-3.0 there has been a run-time notice upon "no-hlt" invocations
indicating that it would be removed in 2012.

Signed-off-by: Len Brown <len.brown@intel.com>
Cc: x86@kernel.org

1 files changed, 0 insertions, 2 deletions

diff --git a/arch/x86/kernel/cpu/proc.c b/arch/x86/kernel/cpu/proc.c
index 3286a92e662a..e280253f6f94 100644
--- a/arch/x86/kernel/cpu/proc.c
+++ b/arch/x86/kernel/cpu/proc.c
@@ -28,7 +28,6 @@ static void show_cpuinfo_misc(struct seq_file *m, struct cpuinfo_x86 *c)
 {
 	seq_printf(m,
 		   "fdiv_bug\t: %s\n"
-		   "hlt_bug\t\t: %s\n"
 		   "f00f_bug\t: %s\n"
 		   "coma_bug\t: %s\n"
 		   "fpu\t\t: %s\n"
@@ -36,7 +35,6 @@ static void show_cpuinfo_misc(struct seq_file *m, struct cpuinfo_x86 *c)
 		   "cpuid level\t: %d\n"
 		   "wp\t\t: %s\n",
 		   c->fdiv_bug ? "yes" : "no",
-		   c->hlt_works_ok ? "no" : "yes",
 		   c->f00f_bug ? "yes" : "no",
 		   c->coma_bug ? "yes" : "no",
 		   c->hard_math ? "yes" : "no",