[PATCH 1/2] x86: move warning message of polling idle and HT enabled

[Hiroshi Shimamoto]

From: Hiroshi Shimamoto <[EMAIL PROTECTED]>
Subject: [PATCH] x86: move warning message of polling idle and HT enabled

The warning message at idle_setup() is never shown because smp_num_sibling 
hasn't
been updated at this point yet.

Move this polling idle and HT enabled warning to select_idle_routine().
I also implement this warning on 64-bit kernel.

Signed-off-by: Hiroshi Shimamoto <[EMAIL PROTECTED]>
---
 arch/x86/kernel/process_32.c |   18 ++++++++++++------
 arch/x86/kernel/process_64.c |   17 ++++++++++++-----
 2 files changed, 24 insertions(+), 11 deletions(-)

diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c
index 69a69c3..d52c032 100644
--- a/arch/x86/kernel/process_32.c
+++ b/arch/x86/kernel/process_32.c
@@ -287,17 +287,27 @@ static void mwait_idle(void)
 
 void __cpuinit select_idle_routine(const struct cpuinfo_x86 *c)
 {
+       static int selected;
+
+       if (selected)
+               return;
+#ifdef CONFIG_X86_SMP
+       if (pm_idle == poll_idle && smp_num_siblings > 1) {
+               printk(KERN_WARNING "WARNING: polling idle and HT enabled,"
+                       " performance may degrade.\n");
+       }
+#endif
        if (cpu_has(c, X86_FEATURE_MWAIT)) {
-               printk("monitor/mwait feature present.\n");
                /*
                 * Skip, if setup has overridden idle.
                 * One CPU supports mwait => All CPUs supports mwait
                 */
                if (!pm_idle) {
-                       printk("using mwait in idle threads.\n");
+                       printk(KERN_INFO "using mwait in idle threads.\n");
                        pm_idle = mwait_idle;
                }
        }
+       selected = 1;
 }
 
 static int __init idle_setup(char *str)
@@ -305,10 +315,6 @@ static int __init idle_setup(char *str)
        if (!strcmp(str, "poll")) {
                printk("using polling idle threads.\n");
                pm_idle = poll_idle;
-#ifdef CONFIG_X86_SMP
-               if (smp_num_siblings > 1)
-                       printk("WARNING: polling idle and HT enabled, 
performance may degrade.\n");
-#endif
        } else if (!strcmp(str, "mwait"))
                force_mwait = 1;
        else
diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index 5e12edd..8cff606 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -282,20 +282,27 @@ static void mwait_idle(void)
 
 void __cpuinit select_idle_routine(const struct cpuinfo_x86 *c)
 {
-       static int printed;
+       static int selected;
+
+       if (selected)
+               return;
+#ifdef CONFIG_X86_SMP
+       if (pm_idle == poll_idle && smp_num_siblings > 1) {
+               printk(KERN_WARNING "WARNING: polling idle and HT enabled,"
+                       " performance may degrade.\n");
+       }
+#endif
        if (cpu_has(c, X86_FEATURE_MWAIT)) {
                /*
                 * Skip, if setup has overridden idle.
                 * One CPU supports mwait => All CPUs supports mwait
                 */
                if (!pm_idle) {
-                       if (!printed) {
-                               printk(KERN_INFO "using mwait in idle 
threads.\n");
-                               printed = 1;
-                       }
+                       printk(KERN_INFO "using mwait in idle threads.\n");
                        pm_idle = mwait_idle;
                }
        }
+       selected = 1;
 }
 
 static int __init idle_setup(char *str)
-- 
1.5.3.6

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