[PATCH] s390: atomic primitives
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>
diff --git a/arch/s390/kernel/machine_kexec.c b/arch/s390/kernel/machine_kexec.c
index 5aa71b0..f0ed5c6 100644
--- a/arch/s390/kernel/machine_kexec.c
+++ b/arch/s390/kernel/machine_kexec.c
@@ -85,7 +85,7 @@
pfault_fini();
#endif
- if (atomic_compare_and_swap(-1, smp_processor_id(), &cpuid))
+ 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 */
diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c
index 5856b3f..bd5b311 100644
--- a/arch/s390/kernel/smp.c
+++ b/arch/s390/kernel/smp.c
@@ -263,7 +263,7 @@
int cpu;
static atomic_t cpuid = ATOMIC_INIT(-1);
- if (atomic_compare_and_swap(-1, smp_processor_id(), &cpuid))
+ 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 */
@@ -313,7 +313,7 @@
{
static atomic_t cpuid = ATOMIC_INIT(-1);
- if (atomic_compare_and_swap(-1, smp_processor_id(), &cpuid) == 0) {
+ if (atomic_cmpxchg(&cpuid, -1, smp_processor_id()) == -1) {
smp_send_stop();
if (MACHINE_IS_VM && strlen(vmhalt_cmd) > 0)
cpcmd(vmhalt_cmd, NULL, 0, NULL);
@@ -332,7 +332,7 @@
{
static atomic_t cpuid = ATOMIC_INIT(-1);
- if (atomic_compare_and_swap(-1, smp_processor_id(), &cpuid) == 0) {
+ if (atomic_cmpxchg(&cpuid, -1, smp_processor_id()) == -1) {
smp_send_stop();
if (MACHINE_IS_VM && strlen(vmpoff_cmd) > 0)
cpcmd(vmpoff_cmd, NULL, 0, NULL);
diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c
index 7008d32..6278739 100644
--- a/drivers/s390/block/dasd.c
+++ b/drivers/s390/block/dasd.c
@@ -7,7 +7,7 @@
* Bugreports.to..: <Linux390@de.ibm.com>
* (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 1999-2001
*
- * $Revision: 1.167 $
+ * $Revision: 1.169 $
*/
#include <linux/config.h>
@@ -1323,7 +1323,7 @@
dasd_schedule_bh(struct dasd_device * device)
{
/* Protect against rescheduling. */
- if (atomic_compare_and_swap (0, 1, &device->tasklet_scheduled))
+ if (atomic_cmpxchg (&device->tasklet_scheduled, 0, 1) != 0)
return;
dasd_get_device(device);
tasklet_hi_schedule(&device->tasklet);
diff --git a/drivers/s390/char/sclp_quiesce.c b/drivers/s390/char/sclp_quiesce.c
index 83f7577..56fa691 100644
--- a/drivers/s390/char/sclp_quiesce.c
+++ b/drivers/s390/char/sclp_quiesce.c
@@ -32,7 +32,7 @@
psw_t quiesce_psw;
int cpu;
- if (atomic_compare_and_swap(-1, smp_processor_id(), &cpuid))
+ 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) {
diff --git a/drivers/s390/char/tape_block.c b/drivers/s390/char/tape_block.c
index 1efc9f2..482e07e 100644
--- a/drivers/s390/char/tape_block.c
+++ b/drivers/s390/char/tape_block.c
@@ -65,7 +65,7 @@
tapeblock_trigger_requeue(struct tape_device *device)
{
/* Protect against rescheduling. */
- if (atomic_compare_and_swap(0, 1, &device->blk_data.requeue_scheduled))
+ if (atomic_cmpxchg(&device->blk_data.requeue_scheduled, 0, 1) != 0)
return;
schedule_work(&device->blk_data.requeue_task);
}
diff --git a/drivers/s390/cio/ccwgroup.c b/drivers/s390/cio/ccwgroup.c
index be9d2d6..e849289 100644
--- a/drivers/s390/cio/ccwgroup.c
+++ b/drivers/s390/cio/ccwgroup.c
@@ -1,7 +1,7 @@
/*
* drivers/s390/cio/ccwgroup.c
* bus driver for ccwgroup
- * $Revision: 1.32 $
+ * $Revision: 1.33 $
*
* Copyright (C) 2002 IBM Deutschland Entwicklung GmbH,
* IBM Corporation
@@ -263,7 +263,7 @@
struct ccwgroup_driver *gdrv;
int ret;
- if (atomic_compare_and_swap(0, 1, &gdev->onoff))
+ if (atomic_cmpxchg(&gdev->onoff, 0, 1) != 0)
return -EAGAIN;
if (gdev->state == CCWGROUP_ONLINE) {
ret = 0;
@@ -289,7 +289,7 @@
struct ccwgroup_driver *gdrv;
int ret;
- if (atomic_compare_and_swap(0, 1, &gdev->onoff))
+ if (atomic_cmpxchg(&gdev->onoff, 0, 1) != 0)
return -EAGAIN;
if (gdev->state == CCWGROUP_OFFLINE) {
ret = 0;
diff --git a/drivers/s390/cio/device.c b/drivers/s390/cio/device.c
index 85908ca..0590cff 100644
--- a/drivers/s390/cio/device.c
+++ b/drivers/s390/cio/device.c
@@ -1,7 +1,7 @@
/*
* drivers/s390/cio/device.c
* bus driver for ccw devices
- * $Revision: 1.131 $
+ * $Revision: 1.137 $
*
* Copyright (C) 2002 IBM Deutschland Entwicklung GmbH,
* IBM Corporation
@@ -374,7 +374,7 @@
int i, force, ret;
char *tmp;
- if (atomic_compare_and_swap(0, 1, &cdev->private->onoff))
+ if (atomic_cmpxchg(&cdev->private->onoff, 0, 1) != 0)
return -EAGAIN;
if (cdev->drv && !try_module_get(cdev->drv->owner)) {
diff --git a/drivers/s390/net/iucv.c b/drivers/s390/net/iucv.c
index df7647c..ecb2f8f 100644
--- a/drivers/s390/net/iucv.c
+++ b/drivers/s390/net/iucv.c
@@ -1,5 +1,5 @@
/*
- * $Id: iucv.c,v 1.45 2005/04/26 22:59:06 braunu Exp $
+ * $Id: iucv.c,v 1.47 2005/11/21 11:35:22 mschwide Exp $
*
* IUCV network driver
*
@@ -29,7 +29,7 @@
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
- * RELEASE-TAG: IUCV lowlevel driver $Revision: 1.45 $
+ * RELEASE-TAG: IUCV lowlevel driver $Revision: 1.47 $
*
*/
@@ -355,7 +355,7 @@
static void
iucv_banner(void)
{
- char vbuf[] = "$Revision: 1.45 $";
+ char vbuf[] = "$Revision: 1.47 $";
char *version = vbuf;
if ((version = strchr(version, ':'))) {
@@ -477,7 +477,7 @@
ptr++;
if (ptr >= iucv_param_pool + PARAM_POOL_SIZE)
ptr = iucv_param_pool;
- } while (atomic_compare_and_swap(0, 1, &ptr->in_use));
+ } while (atomic_cmpxchg(&ptr->in_use, 0, 1) != 0);
hint = ptr - iucv_param_pool;
memset(&ptr->param, 0, sizeof(ptr->param));
diff --git a/drivers/s390/net/qeth_main.c b/drivers/s390/net/qeth_main.c
index f8f55cc..7b2663f 100644
--- a/drivers/s390/net/qeth_main.c
+++ b/drivers/s390/net/qeth_main.c
@@ -1396,7 +1396,7 @@
channel->ccw.cda = (__u32) __pa(iob->data);
wait_event(card->wait_q,
- atomic_compare_and_swap(0,1,&channel->irq_pending) == 0);
+ atomic_cmpxchg(&channel->irq_pending, 0, 1) == 0);
QETH_DBF_TEXT(setup, 6, "noirqpnd");
spin_lock_irqsave(get_ccwdev_lock(channel->ccwdev), flags);
rc = ccw_device_start(channel->ccwdev,
@@ -1463,7 +1463,7 @@
memcpy(QETH_IDX_ACT_QDIO_DEV_REALADDR(iob->data), &temp, 2);
wait_event(card->wait_q,
- atomic_compare_and_swap(0,1,&channel->irq_pending) == 0);
+ atomic_cmpxchg(&channel->irq_pending, 0, 1) == 0);
QETH_DBF_TEXT(setup, 6, "noirqpnd");
spin_lock_irqsave(get_ccwdev_lock(channel->ccwdev), flags);
rc = ccw_device_start(channel->ccwdev,
@@ -1616,7 +1616,7 @@
}
qeth_setup_ccw(&card->read, iob->data, QETH_BUFSIZE);
wait_event(card->wait_q,
- atomic_compare_and_swap(0,1,&card->read.irq_pending) == 0);
+ atomic_cmpxchg(&card->read.irq_pending, 0, 1) == 0);
QETH_DBF_TEXT(trace, 6, "noirqpnd");
rc = ccw_device_start(card->read.ccwdev, &card->read.ccw,
(addr_t) iob, 0, 0);
@@ -1882,7 +1882,7 @@
spin_unlock_irqrestore(&card->lock, flags);
QETH_DBF_HEX(control, 2, iob->data, QETH_DBF_CONTROL_LEN);
wait_event(card->wait_q,
- atomic_compare_and_swap(0,1,&card->write.irq_pending) == 0);
+ atomic_cmpxchg(&card->write.irq_pending, 0, 1) == 0);
qeth_prepare_control_data(card, len, iob);
if (IS_IPA(iob->data))
timer.expires = jiffies + QETH_IPA_TIMEOUT;
@@ -1924,7 +1924,7 @@
QETH_DBF_TEXT(trace, 5, "osndctrd");
wait_event(card->wait_q,
- atomic_compare_and_swap(0,1,&card->write.irq_pending) == 0);
+ atomic_cmpxchg(&card->write.irq_pending, 0, 1) == 0);
qeth_prepare_control_data(card, len, iob);
QETH_DBF_TEXT(trace, 6, "osnoirqp");
spin_lock_irqsave(get_ccwdev_lock(card->write.ccwdev), flags);
@@ -4236,9 +4236,8 @@
QETH_DBF_TEXT(trace, 6, "dosndpfa");
/* spin until we get the queue ... */
- while (atomic_compare_and_swap(QETH_OUT_Q_UNLOCKED,
- QETH_OUT_Q_LOCKED,
- &queue->state));
+ while (atomic_cmpxchg(&queue->state, QETH_OUT_Q_UNLOCKED,
+ QETH_OUT_Q_LOCKED) != QETH_OUT_Q_UNLOCKED);
/* ... now we've got the queue */
index = queue->next_buf_to_fill;
buffer = &queue->bufs[queue->next_buf_to_fill];
@@ -4292,9 +4291,8 @@
QETH_DBF_TEXT(trace, 6, "dosndpkt");
/* spin until we get the queue ... */
- while (atomic_compare_and_swap(QETH_OUT_Q_UNLOCKED,
- QETH_OUT_Q_LOCKED,
- &queue->state));
+ while (atomic_cmpxchg(&queue->state, QETH_OUT_Q_UNLOCKED,
+ QETH_OUT_Q_LOCKED) != QETH_OUT_Q_UNLOCKED);
start_index = queue->next_buf_to_fill;
buffer = &queue->bufs[queue->next_buf_to_fill];
/*
diff --git a/include/asm-s390/atomic.h b/include/asm-s390/atomic.h
index 6d07c7d..d82aedf 100644
--- a/include/asm-s390/atomic.h
+++ b/include/asm-s390/atomic.h
@@ -5,7 +5,7 @@
* include/asm-s390/atomic.h
*
* S390 version
- * Copyright (C) 1999-2003 IBM Deutschland Entwicklung GmbH, IBM Corporation
+ * Copyright (C) 1999-2005 IBM Deutschland Entwicklung GmbH, IBM Corporation
* Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
* Denis Joseph Barrow,
* Arnd Bergmann (arndb@de.ibm.com)
@@ -45,59 +45,57 @@
#define atomic_read(v) ((v)->counter)
#define atomic_set(v,i) (((v)->counter) = (i))
-static __inline__ void atomic_add(int i, atomic_t * v)
-{
- __CS_LOOP(v, i, "ar");
-}
static __inline__ int atomic_add_return(int i, atomic_t * v)
{
return __CS_LOOP(v, i, "ar");
}
-static __inline__ int atomic_add_negative(int i, atomic_t * v)
-{
- return __CS_LOOP(v, i, "ar") < 0;
-}
-static __inline__ void atomic_sub(int i, atomic_t * v)
-{
- __CS_LOOP(v, i, "sr");
-}
+#define atomic_add(_i, _v) atomic_add_return(_i, _v)
+#define atomic_add_negative(_i, _v) (atomic_add_return(_i, _v) < 0)
+#define atomic_inc(_v) atomic_add_return(1, _v)
+#define atomic_inc_return(_v) atomic_add_return(1, _v)
+#define atomic_inc_and_test(_v) (atomic_add_return(1, _v) == 0)
+
static __inline__ int atomic_sub_return(int i, atomic_t * v)
{
return __CS_LOOP(v, i, "sr");
}
-static __inline__ void atomic_inc(volatile atomic_t * v)
-{
- __CS_LOOP(v, 1, "ar");
-}
-static __inline__ int atomic_inc_return(volatile atomic_t * v)
-{
- return __CS_LOOP(v, 1, "ar");
-}
+#define atomic_sub(_i, _v) atomic_sub_return(_i, _v)
+#define atomic_sub_and_test(_i, _v) (atomic_sub_return(_i, _v) == 0)
+#define atomic_dec(_v) atomic_sub_return(1, _v)
+#define atomic_dec_return(_v) atomic_sub_return(1, _v)
+#define atomic_dec_and_test(_v) (atomic_sub_return(1, _v) == 0)
-static __inline__ int atomic_inc_and_test(volatile atomic_t * v)
-{
- return __CS_LOOP(v, 1, "ar") == 0;
-}
-static __inline__ void atomic_dec(volatile atomic_t * v)
-{
- __CS_LOOP(v, 1, "sr");
-}
-static __inline__ int atomic_dec_return(volatile atomic_t * v)
-{
- return __CS_LOOP(v, 1, "sr");
-}
-static __inline__ int atomic_dec_and_test(volatile atomic_t * v)
-{
- return __CS_LOOP(v, 1, "sr") == 0;
-}
static __inline__ void atomic_clear_mask(unsigned long mask, atomic_t * v)
{
__CS_LOOP(v, ~mask, "nr");
}
+
static __inline__ void atomic_set_mask(unsigned long mask, atomic_t * v)
{
__CS_LOOP(v, mask, "or");
}
+
+static __inline__ int atomic_cmpxchg(atomic_t *v, int old, int new)
+{
+ __asm__ __volatile__(" cs %0,%3,0(%2)\n"
+ : "+d" (old), "=m" (v->counter)
+ : "a" (v), "d" (new), "m" (v->counter)
+ : "cc", "memory" );
+ return old;
+}
+
+static __inline__ int atomic_add_unless(atomic_t *v, int a, int u)
+{
+ int c, old;
+
+ c = atomic_read(v);
+ while (c != u && (old = atomic_cmpxchg(v, c, c + a)) != c)
+ c = old;
+ return c != u;
+}
+
+#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
+
#undef __CS_LOOP
#ifdef __s390x__
@@ -123,92 +121,61 @@
#define atomic64_read(v) ((v)->counter)
#define atomic64_set(v,i) (((v)->counter) = (i))
-static __inline__ void atomic64_add(long long i, atomic64_t * v)
-{
- __CSG_LOOP(v, i, "agr");
-}
static __inline__ long long atomic64_add_return(long long i, atomic64_t * v)
{
return __CSG_LOOP(v, i, "agr");
}
-static __inline__ long long atomic64_add_negative(long long i, atomic64_t * v)
+#define atomic64_add(_i, _v) atomic64_add_return(_i, _v)
+#define atomic64_add_negative(_i, _v) (atomic64_add_return(_i, _v) < 0)
+#define atomic64_inc(_v) atomic64_add_return(1, _v)
+#define atomic64_inc_return(_v) atomic64_add_return(1, _v)
+#define atomic64_inc_and_test(_v) (atomic64_add_return(1, _v) == 0)
+
+static __inline__ long long atomic64_sub_return(long long i, atomic64_t * v)
{
- return __CSG_LOOP(v, i, "agr") < 0;
+ return __CSG_LOOP(v, i, "sgr");
}
-static __inline__ void atomic64_sub(long long i, atomic64_t * v)
-{
- __CSG_LOOP(v, i, "sgr");
-}
-static __inline__ void atomic64_inc(volatile atomic64_t * v)
-{
- __CSG_LOOP(v, 1, "agr");
-}
-static __inline__ long long atomic64_inc_return(volatile atomic64_t * v)
-{
- return __CSG_LOOP(v, 1, "agr");
-}
-static __inline__ long long atomic64_inc_and_test(volatile atomic64_t * v)
-{
- return __CSG_LOOP(v, 1, "agr") == 0;
-}
-static __inline__ void atomic64_dec(volatile atomic64_t * v)
-{
- __CSG_LOOP(v, 1, "sgr");
-}
-static __inline__ long long atomic64_dec_return(volatile atomic64_t * v)
-{
- return __CSG_LOOP(v, 1, "sgr");
-}
-static __inline__ long long atomic64_dec_and_test(volatile atomic64_t * v)
-{
- return __CSG_LOOP(v, 1, "sgr") == 0;
-}
+#define atomic64_sub(_i, _v) atomic64_sub_return(_i, _v)
+#define atomic64_sub_and_test(_i, _v) (atomic64_sub_return(_i, _v) == 0)
+#define atomic64_dec(_v) atomic64_sub_return(1, _v)
+#define atomic64_dec_return(_v) atomic64_sub_return(1, _v)
+#define atomic64_dec_and_test(_v) (atomic64_sub_return(1, _v) == 0)
+
static __inline__ void atomic64_clear_mask(unsigned long mask, atomic64_t * v)
{
__CSG_LOOP(v, ~mask, "ngr");
}
+
static __inline__ void atomic64_set_mask(unsigned long mask, atomic64_t * v)
{
__CSG_LOOP(v, mask, "ogr");
}
-#undef __CSG_LOOP
-#endif
-
-/*
- returns 0 if expected_oldval==value in *v ( swap was successful )
- returns 1 if unsuccessful.
-
- This is non-portable, use bitops or spinlocks instead!
-*/
-static __inline__ int
-atomic_compare_and_swap(int expected_oldval,int new_val,atomic_t *v)
+static __inline__ long long atomic64_cmpxchg(atomic64_t *v,
+ long long old, long long new)
{
- int retval;
-
- __asm__ __volatile__(
- " lr %0,%3\n"
- " cs %0,%4,0(%2)\n"
- " ipm %0\n"
- " srl %0,28\n"
- "0:"
- : "=&d" (retval), "=m" (v->counter)
- : "a" (v), "d" (expected_oldval) , "d" (new_val),
- "m" (v->counter) : "cc", "memory" );
- return retval;
+ __asm__ __volatile__(" csg %0,%3,0(%2)\n"
+ : "+d" (old), "=m" (v->counter)
+ : "a" (v), "d" (new), "m" (v->counter)
+ : "cc", "memory" );
+ return old;
}
-#define atomic_cmpxchg(v, o, n) (atomic_compare_and_swap((o), (n), &((v)->counter)))
+static __inline__ int atomic64_add_unless(atomic64_t *v,
+ long long a, long long u)
+{
+ long long c, old;
-#define atomic_add_unless(v, a, u) \
-({ \
- int c, old; \
- c = atomic_read(v); \
- while (c != (u) && (old = atomic_cmpxchg((v), c, c + (a))) != c) \
- c = old; \
- c != (u); \
-})
-#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
+ c = atomic64_read(v);
+ while (c != u && (old = atomic64_cmpxchg(v, c, c + a)) != c)
+ c = old;
+ return c != u;
+}
+
+#define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1, 0)
+
+#undef __CSG_LOOP
+#endif
#define smp_mb__before_atomic_dec() smp_mb()
#define smp_mb__after_atomic_dec() smp_mb()