2008-11-27 10:38:26

by Martin Schwidefsky

[permalink] [raw]
Subject: [patch 06/60] convert s390 to generic IPI infrastructure

From: Heiko Carstens <[email protected]>

Since etr/stp don't need the old smp_call_function semantics anymore
we can convert s390 to the generic IPI infrastructure.

Signed-off-by: Heiko Carstens <[email protected]>
Signed-off-by: Martin Schwidefsky <[email protected]>
---

arch/s390/Kconfig | 1
arch/s390/include/asm/sigp.h | 1
arch/s390/include/asm/smp.h | 5 -
arch/s390/kernel/smp.c | 175 ++++---------------------------------------
4 files changed, 24 insertions(+), 158 deletions(-)

Index: quilt-2.6/arch/s390/include/asm/sigp.h
===================================================================
--- quilt-2.6.orig/arch/s390/include/asm/sigp.h
+++ quilt-2.6/arch/s390/include/asm/sigp.h
@@ -61,6 +61,7 @@ typedef enum
{
ec_schedule=0,
ec_call_function,
+ ec_call_function_single,
ec_bit_last
} ec_bit_sig;

Index: quilt-2.6/arch/s390/include/asm/smp.h
===================================================================
--- quilt-2.6.orig/arch/s390/include/asm/smp.h
+++ quilt-2.6/arch/s390/include/asm/smp.h
@@ -91,8 +91,9 @@ extern int __cpu_up (unsigned int cpu);
extern struct mutex smp_cpu_state_mutex;
extern int smp_cpu_polarization[];

-extern int smp_call_function_mask(cpumask_t mask, void (*func)(void *),
- void *info, int wait);
+extern void arch_send_call_function_single_ipi(int cpu);
+extern void arch_send_call_function_ipi(cpumask_t mask);
+
#endif

#ifndef CONFIG_SMP
Index: quilt-2.6/arch/s390/Kconfig
===================================================================
--- quilt-2.6.orig/arch/s390/Kconfig
+++ quilt-2.6/arch/s390/Kconfig
@@ -73,6 +73,7 @@ mainmenu "Linux Kernel Configuration"

config S390
def_bool y
+ select USE_GENERIC_SMP_HELPERS if SMP
select HAVE_OPROFILE
select HAVE_KPROBES
select HAVE_KRETPROBES
Index: quilt-2.6/arch/s390/kernel/smp.c
===================================================================
--- quilt-2.6.orig/arch/s390/kernel/smp.c
+++ quilt-2.6/arch/s390/kernel/smp.c
@@ -77,159 +77,6 @@ static DEFINE_PER_CPU(struct cpu, cpu_de

static void smp_ext_bitcall(int, ec_bit_sig);

-/*
- * Structure and data for __smp_call_function_map(). This is designed to
- * minimise static memory requirements. It also looks cleaner.
- */
-static DEFINE_SPINLOCK(call_lock);
-
-struct call_data_struct {
- void (*func) (void *info);
- void *info;
- cpumask_t started;
- cpumask_t finished;
- int wait;
-};
-
-static struct call_data_struct *call_data;
-
-/*
- * 'Call function' interrupt callback
- */
-static void do_call_function(void)
-{
- void (*func) (void *info) = call_data->func;
- void *info = call_data->info;
- int wait = call_data->wait;
-
- cpu_set(smp_processor_id(), call_data->started);
- (*func)(info);
- if (wait)
- cpu_set(smp_processor_id(), call_data->finished);;
-}
-
-static void __smp_call_function_map(void (*func) (void *info), void *info,
- int wait, cpumask_t map)
-{
- struct call_data_struct data;
- int cpu, local = 0;
-
- /*
- * Can deadlock when interrupts are disabled or if in wrong context.
- */
- WARN_ON(irqs_disabled() || in_irq());
-
- /*
- * Check for local function call. We have to have the same call order
- * as in on_each_cpu() because of machine_restart_smp().
- */
- if (cpu_isset(smp_processor_id(), map)) {
- local = 1;
- cpu_clear(smp_processor_id(), map);
- }
-
- cpus_and(map, map, cpu_online_map);
- if (cpus_empty(map))
- goto out;
-
- data.func = func;
- data.info = info;
- data.started = CPU_MASK_NONE;
- data.wait = wait;
- if (wait)
- data.finished = CPU_MASK_NONE;
-
- call_data = &data;
-
- for_each_cpu_mask(cpu, map)
- smp_ext_bitcall(cpu, ec_call_function);
-
- /* Wait for response */
- while (!cpus_equal(map, data.started))
- cpu_relax();
- if (wait)
- while (!cpus_equal(map, data.finished))
- cpu_relax();
-out:
- if (local) {
- local_irq_disable();
- func(info);
- local_irq_enable();
- }
-}
-
-/*
- * smp_call_function:
- * @func: the function to run; this must be fast and non-blocking
- * @info: an arbitrary pointer to pass to the function
- * @wait: if true, wait (atomically) until function has completed on other CPUs
- *
- * Run a function on all other CPUs.
- *
- * You must not call this function with disabled interrupts, from a
- * hardware interrupt handler or from a bottom half.
- */
-int smp_call_function(void (*func) (void *info), void *info, int wait)
-{
- cpumask_t map;
-
- spin_lock(&call_lock);
- map = cpu_online_map;
- cpu_clear(smp_processor_id(), map);
- __smp_call_function_map(func, info, wait, map);
- spin_unlock(&call_lock);
- return 0;
-}
-EXPORT_SYMBOL(smp_call_function);
-
-/*
- * smp_call_function_single:
- * @cpu: the CPU where func should run
- * @func: the function to run; this must be fast and non-blocking
- * @info: an arbitrary pointer to pass to the function
- * @wait: if true, wait (atomically) until function has completed on other CPUs
- *
- * Run a function on one processor.
- *
- * You must not call this function with disabled interrupts, from a
- * hardware interrupt handler or from a bottom half.
- */
-int smp_call_function_single(int cpu, void (*func) (void *info), void *info,
- int wait)
-{
- spin_lock(&call_lock);
- __smp_call_function_map(func, info, wait, cpumask_of_cpu(cpu));
- spin_unlock(&call_lock);
- return 0;
-}
-EXPORT_SYMBOL(smp_call_function_single);
-
-/**
- * smp_call_function_mask(): Run a function on a set of other CPUs.
- * @mask: The set of cpus to run on. Must not include the current cpu.
- * @func: The function to run. This must be fast and non-blocking.
- * @info: An arbitrary pointer to pass to the function.
- * @wait: If true, wait (atomically) until function has completed on other CPUs.
- *
- * Returns 0 on success, else a negative status code.
- *
- * If @wait is true, then returns once @func has returned; otherwise
- * it returns just before the target cpu calls @func.
- *
- * You must not call this function with disabled interrupts or from a
- * hardware interrupt handler or from a bottom half handler.
- */
-int smp_call_function_mask(cpumask_t mask, void (*func)(void *), void *info,
- int wait)
-{
- spin_lock(&call_lock);
- cpu_clear(smp_processor_id(), mask);
- __smp_call_function_map(func, info, wait, mask);
- spin_unlock(&call_lock);
- return 0;
-}
-EXPORT_SYMBOL(smp_call_function_mask);
-
void smp_send_stop(void)
{
int cpu, rc;
@@ -271,7 +118,10 @@ static void do_ext_call_interrupt(__u16
bits = xchg(&S390_lowcore.ext_call_fast, 0);

if (test_bit(ec_call_function, &bits))
- do_call_function();
+ generic_smp_call_function_interrupt();
+
+ if (test_bit(ec_call_function_single, &bits))
+ generic_smp_call_function_single_interrupt();
}

/*
@@ -288,6 +138,19 @@ static void smp_ext_bitcall(int cpu, ec_
udelay(10);
}

+void arch_send_call_function_ipi(cpumask_t mask)
+{
+ int cpu;
+
+ for_each_cpu_mask(cpu, mask)
+ smp_ext_bitcall(cpu, ec_call_function);
+}
+
+void arch_send_call_function_single_ipi(int cpu)
+{
+ smp_ext_bitcall(cpu, ec_call_function_single);
+}
+
#ifndef CONFIG_64BIT
/*
* this function sends a 'purge tlb' signal to another CPU.
@@ -588,9 +451,9 @@ int __cpuinit start_secondary(void *cpuv
/* call cpu notifiers */
notify_cpu_starting(smp_processor_id());
/* Mark this cpu as online */
- spin_lock(&call_lock);
+ ipi_call_lock();
cpu_set(smp_processor_id(), cpu_online_map);
- spin_unlock(&call_lock);
+ ipi_call_unlock();
/* Switch on interrupts */
local_irq_enable();
/* Print info about this processor */

--
blue skies,
Martin.

"Reality continues to ruin my life." - Calvin.