[PATCH] Timer interrupt cleanups [3/3] - normalise calls

Martin J. Bligh (mbligh@aracnet.com)
Sun, 05 Jan 2003 18:35:22 -0800


This patch moves x86_do_profile and update_process_times into
do_local_timer for all systems.

It also makes do_global_timer_interrupt call do_local_timer on systems
without the local apic timer (local apic timer simulation)

--------------------

Assuming we're SMP with a local apic timer all firing away:

global_timer_interrupt
do_global_timer_interrupt
{ack the interrupt}
do_global_timer_interrupt_hook
do_global_timer
jiffies_64++;
update_times
{update CMOS clock} (In the interrupt still ??!!)

local_apic_timer_interrupt
do_local_apic_timer_interrupt
{ack the interrupt}
do_local_timer
x86_do_profile
update_process_times

--------------------

On UP with local apic timer:

global_timer_interrupt
do_global_timer_interrupt
{ack the interrupt}
do_global_timer_interrupt_hook
do_global_timer
jiffies_64++;
update_times
{update CMOS clock} (In the interrupt still ??!!)

local_apic_timer_interrupt
do_local_apic_timer_interrupt
{ack the interrupt}
do_local_timer
x86_do_profile
update_process_times

--------------------

On a UP 386 with stale crusty breadcrumbs, and no local timer:

global_timer_interrupt
do_global_timer_interrupt
{ack the interrupt}
do_global_timer_interrupt_hook
do_global_timer
jiffies_64++;
update_times
do_local_timer
x86_do_profile
update_process_times
{update CMOS clock} (In the interrupt still ??!!)

--------------------
diff -urpN -X /home/fletch/.diff.exclude
02-rename_local_timer/arch/i386/kernel/apic.c
03-normalise_placement/arch/i386/kernel/apic.c
--- 02-rename_local_timer/arch/i386/kernel/apic.c Sun Jan 5 10:53:14 2003
+++ 03-normalise_placement/arch/i386/kernel/apic.c Sun Jan 5 10:56:31 2003
@@ -1012,11 +1012,18 @@ inline void do_local_timer(struct pt_reg
prof_old_multiplier[cpu] = prof_counter[cpu];
}

+ /*
+ * This is a bit of a mess ... not sure if we use multipliers
+ * on SMP ... the old code didn't. Someone who understands
+ * this better should clean up the #ifdef's below - mbligh
+ */
#ifdef CONFIG_SMP
update_process_times(user_mode(regs));
#endif
}
-
+#ifndef CONFIG_SMP
+ update_process_times(user_mode(regs));
+#endif
/*
* We take the 'long' return path, and there every subsystem
* grabs the apropriate locks (kernel lock/ irq lock).
diff -urpN -X /home/fletch/.diff.exclude
02-rename_local_timer/include/asm-i386/mach-default/do_timer.h
03-normalise_placement/include/asm-i386/mach-default/do_timer.h
--- 02-rename_local_timer/include/asm-i386/mach-default/do_timer.h Sun Jan
5 10:51:02 2003
+++ 03-normalise_placement/include/asm-i386/mach-default/do_timer.h Sun Jan
5 10:56:31 2003
@@ -16,17 +16,9 @@
static inline void do_global_timer_interrupt_hook(struct pt_regs *regs)
{
do_global_timer(regs);
-/*
- * In the SMP case we use the local APIC timer interrupt to do the
- * profiling, except when we simulate SMP mode on a uniprocessor
- * system, in that case we have to call the local interrupt handler.
- */
-#ifndef CONFIG_X86_LOCAL_APIC
- x86_do_profile(regs);
-#else
+
if (!using_apic_timer)
do_local_timer(regs);
-#endif
}

diff -urpN -X /home/fletch/.diff.exclude
02-rename_local_timer/include/asm-i386/mach-visws/do_timer.h
03-normalise_placement/include/asm-i386/mach-visws/do_timer.h
--- 02-rename_local_timer/include/asm-i386/mach-visws/do_timer.h Sun Jan 5
10:51:02 2003
+++ 03-normalise_placement/include/asm-i386/mach-visws/do_timer.h Sun Jan
5 10:56:31 2003
@@ -9,17 +9,9 @@ static inline void do_global_timer_inter
co_cpu_write(CO_CPU_STAT,co_cpu_read(CO_CPU_STAT) & ~CO_STAT_TIMEINTR);

do_global_timer(regs);
-/*
- * In the SMP case we use the local APIC timer interrupt to do the
- * profiling, except when we simulate SMP mode on a uniprocessor
- * system, in that case we have to call the local interrupt handler.
- */
-#ifndef CONFIG_X86_LOCAL_APIC
- x86_do_profile(regs);
-#else
+
if (!using_apic_timer)
do_local_timer(regs);
-#endif
}

static inline int do_timer_overflow(int count)
diff -urpN -X /home/fletch/.diff.exclude
02-rename_local_timer/kernel/timer.c 03-normalise_placement/kernel/timer.c
--- 02-rename_local_timer/kernel/timer.c Sat Jan 4 20:08:46 2003
+++ 03-normalise_placement/kernel/timer.c Sun Jan 5 10:56:31 2003
@@ -806,11 +806,6 @@ static inline void update_times(void)
void do_global_timer(struct pt_regs *regs)
{
jiffies_64++;
-#ifndef CONFIG_SMP
- /* SMP process accounting uses the local APIC timer */
-
- update_process_times(user_mode(regs));
-#endif
update_times();
}

-
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