mirror of
https://github.com/adulau/aha.git
synced 2024-12-30 12:46:17 +00:00
973bd99375
Hugh Dickins <hugh@veritas.com> Fix the broken atomic_cmpxchg primitive. Add atomic_sub_and_test, atomic64_sub_return, atomic64_sub_and_test, atomic64_cmpxchg, atomic64_add_unless and atomic64_inc_not_zero. Replace old style atomic_compare_and_swap by atomic_cmpxchg. Shorten the whole header by defining most primitives with the two inline functions atomic_add_return and atomic_sub_return. In addition this patch contains the s390 related fixes of Hugh's "mm: fill arch atomic64 gaps" patch. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Hugh Dickins <hugh@veritas.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
99 lines
2.4 KiB
C
99 lines
2.4 KiB
C
/*
|
|
* drivers/s390/char/sclp_quiesce.c
|
|
* signal quiesce handler
|
|
*
|
|
* (C) Copyright IBM Corp. 1999,2004
|
|
* Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
|
|
* Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
|
|
*/
|
|
|
|
#include <linux/config.h>
|
|
#include <linux/module.h>
|
|
#include <linux/types.h>
|
|
#include <linux/cpumask.h>
|
|
#include <linux/smp.h>
|
|
#include <linux/init.h>
|
|
#include <asm/atomic.h>
|
|
#include <asm/ptrace.h>
|
|
#include <asm/sigp.h>
|
|
|
|
#include "sclp.h"
|
|
|
|
|
|
#ifdef CONFIG_SMP
|
|
/* Signal completion of shutdown process. All CPUs except the first to enter
|
|
* this function: go to stopped state. First CPU: wait until all other
|
|
* CPUs are in stopped or check stop state. Afterwards, load special PSW
|
|
* to indicate completion. */
|
|
static void
|
|
do_load_quiesce_psw(void * __unused)
|
|
{
|
|
static atomic_t cpuid = ATOMIC_INIT(-1);
|
|
psw_t quiesce_psw;
|
|
int cpu;
|
|
|
|
if (atomic_cmpxchg(&cpuid, -1, smp_processor_id()) != -1)
|
|
signal_processor(smp_processor_id(), sigp_stop);
|
|
/* Wait for all other cpus to enter stopped state */
|
|
for_each_online_cpu(cpu) {
|
|
if (cpu == smp_processor_id())
|
|
continue;
|
|
while(!smp_cpu_not_running(cpu))
|
|
cpu_relax();
|
|
}
|
|
/* Quiesce the last cpu with the special psw */
|
|
quiesce_psw.mask = PSW_BASE_BITS | PSW_MASK_WAIT;
|
|
quiesce_psw.addr = 0xfff;
|
|
__load_psw(quiesce_psw);
|
|
}
|
|
|
|
/* Shutdown handler. Perform shutdown function on all CPUs. */
|
|
static void
|
|
do_machine_quiesce(void)
|
|
{
|
|
on_each_cpu(do_load_quiesce_psw, NULL, 0, 0);
|
|
}
|
|
#else
|
|
/* Shutdown handler. Signal completion of shutdown by loading special PSW. */
|
|
static void
|
|
do_machine_quiesce(void)
|
|
{
|
|
psw_t quiesce_psw;
|
|
|
|
quiesce_psw.mask = PSW_BASE_BITS | PSW_MASK_WAIT;
|
|
quiesce_psw.addr = 0xfff;
|
|
__load_psw(quiesce_psw);
|
|
}
|
|
#endif
|
|
|
|
extern void ctrl_alt_del(void);
|
|
|
|
/* Handler for quiesce event. Start shutdown procedure. */
|
|
static void
|
|
sclp_quiesce_handler(struct evbuf_header *evbuf)
|
|
{
|
|
_machine_restart = (void *) do_machine_quiesce;
|
|
_machine_halt = do_machine_quiesce;
|
|
_machine_power_off = do_machine_quiesce;
|
|
ctrl_alt_del();
|
|
}
|
|
|
|
static struct sclp_register sclp_quiesce_event = {
|
|
.receive_mask = EvTyp_SigQuiesce_Mask,
|
|
.receiver_fn = sclp_quiesce_handler
|
|
};
|
|
|
|
/* Initialize quiesce driver. */
|
|
static int __init
|
|
sclp_quiesce_init(void)
|
|
{
|
|
int rc;
|
|
|
|
rc = sclp_register(&sclp_quiesce_event);
|
|
if (rc)
|
|
printk(KERN_WARNING "sclp: could not register quiesce handler "
|
|
"(rc=%d)\n", rc);
|
|
return rc;
|
|
}
|
|
|
|
module_init(sclp_quiesce_init);
|