From: Tomas Hruby <tom@minix3.org>
Date: Thu, 16 Sep 2010 07:18:47 +0000 (+0000)
Subject: apic_timer_x
X-Git-Tag: v3.2.0~836
X-Git-Url: http://zhaoyanbai.com/repos/%22http:/www.isc.org/icons/zlib_tech.html?a=commitdiff_plain;h=72cc01ff48cf4ce12746a72e06ba30fb45d44543;p=minix.git

apic_timer_x

- set the apic_timer_x factor variable to slowdown apic timer in
  virtual machines
---

diff --git a/kernel/arch/i386/apic.c b/kernel/arch/i386/apic.c
index 53bad419c..c6f2155fa 100644
--- a/kernel/arch/i386/apic.c
+++ b/kernel/arch/i386/apic.c
@@ -506,7 +506,7 @@ PUBLIC void lapic_set_timer_one_shot(const u32_t usec)
 	u32_t ticks_per_us;
 	const u8_t cpu = cpuid;
 
-	ticks_per_us = lapic_bus_freq[cpu] / 1000000;
+	ticks_per_us = (lapic_bus_freq[cpu] / 1000000) * config_apic_timer_x;
 
 	lvtt = APIC_TDCR_1;
 	lapic_write(LAPIC_TIMER_DCR, lvtt);
@@ -525,7 +525,7 @@ PUBLIC void lapic_set_timer_periodic(const unsigned freq)
 	u32_t lapic_ticks_per_clock_tick;
 	const u8_t cpu = cpuid;
 
-	lapic_ticks_per_clock_tick = lapic_bus_freq[cpu] / freq;
+	lapic_ticks_per_clock_tick = (lapic_bus_freq[cpu] / freq) * config_apic_timer_x;
 
 	lvtt = APIC_TDCR_1;
 	lapic_write(LAPIC_TIMER_DCR, lvtt);
diff --git a/kernel/glo.h b/kernel/glo.h
index fcbd73a94..1c9eb5137 100644
--- a/kernel/glo.h
+++ b/kernel/glo.h
@@ -54,6 +54,7 @@ EXTERN int verboseflags;
 
 #ifdef CONFIG_APIC
 EXTERN int config_no_apic; /* optionaly turn off apic */
+EXTERN int config_apic_timer_x; /* apic timer slowdown factor */
 #endif
 
 EXTERN u64_t cpu_hz[CONFIG_MAX_CPUS];
diff --git a/kernel/start.c b/kernel/start.c
index 7c6a5cf3c..a39ddb8ef 100644
--- a/kernel/start.c
+++ b/kernel/start.c
@@ -93,6 +93,11 @@ PUBLIC void cstart(
 	config_no_apic = atoi(value);
   else
 	config_no_apic = 1;
+  value = env_get("apic_timer_x");
+  if(value)
+	config_apic_timer_x = atoi(value);
+  else
+	config_apic_timer_x = 1;
 #endif
 
 #ifdef CONFIG_WATCHDOG