From 473e66baad1e83e6c5dfdca65aba03bf21727202 Mon Sep 17 00:00:00 2001
From: Heiko Carstens <heiko.carstens@de.ibm.com>
Date: Wed, 9 May 2012 16:27:39 +0200
Subject: [PATCH] s390/time: always use stckf instead of stck if available
The store clock fast instruction saves a couple of instructions compared
to the store clock instruction. Always use stckf instead of stck if it
is available.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
---
arch/s390/include/asm/setup.h | 3 ---
arch/s390/include/asm/timex.h | 17 +++++------------
arch/s390/kernel/early.c | 2 --
arch/s390/kernel/entry64.S | 16 ++++++++++++----
drivers/s390/cio/qdio_main.c | 4 ++--
5 files changed, 19 insertions(+), 23 deletions(-)
diff --git a/arch/s390/include/asm/setup.h b/arch/s390/include/asm/setup.h
index b21e46e5d4b8..7244e1f64126 100644
--- a/arch/s390/include/asm/setup.h
+++ b/arch/s390/include/asm/setup.h
@@ -82,7 +82,6 @@ extern unsigned int user_mode;
#define MACHINE_FLAG_LPAR (1UL << 12)
#define MACHINE_FLAG_SPP (1UL << 13)
#define MACHINE_FLAG_TOPOLOGY (1UL << 14)
-#define MACHINE_FLAG_STCKF (1UL << 15)
#define MACHINE_IS_VM (S390_lowcore.machine_flags & MACHINE_FLAG_VM)
#define MACHINE_IS_KVM (S390_lowcore.machine_flags & MACHINE_FLAG_KVM)
@@ -101,7 +100,6 @@ extern unsigned int user_mode;
#define MACHINE_HAS_PFMF (0)
#define MACHINE_HAS_SPP (0)
#define MACHINE_HAS_TOPOLOGY (0)
-#define MACHINE_HAS_STCKF (0)
#else /* __s390x__ */
#define MACHINE_HAS_IEEE (1)
#define MACHINE_HAS_CSP (1)
@@ -113,7 +111,6 @@ extern unsigned int user_mode;
#define MACHINE_HAS_PFMF (S390_lowcore.machine_flags & MACHINE_FLAG_PFMF)
#define MACHINE_HAS_SPP (S390_lowcore.machine_flags & MACHINE_FLAG_SPP)
#define MACHINE_HAS_TOPOLOGY (S390_lowcore.machine_flags & MACHINE_FLAG_TOPOLOGY)
-#define MACHINE_HAS_STCKF (S390_lowcore.machine_flags & MACHINE_FLAG_STCKF)
#endif /* __s390x__ */
#define ZFCPDUMP_HSA_SIZE (32UL<<20)
diff --git a/arch/s390/include/asm/timex.h b/arch/s390/include/asm/timex.h
index c447a27a7fdb..72eaa8511a4f 100644
--- a/arch/s390/include/asm/timex.h
+++ b/arch/s390/include/asm/timex.h
@@ -73,11 +73,15 @@ static inline void local_tick_enable(unsigned long long comp)
typedef unsigned long long cycles_t;
-static inline unsigned long long get_clock (void)
+static inline unsigned long long get_clock(void)
{
unsigned long long clk;
+#if defined(CONFIG_64BIT) && !defined(CONFIG_MARCH_Z900) && !defined(CONFIG_MARCH_Z990)
+ asm volatile(".insn s,0xb27c0000,%0" : "=Q" (clk) : : "cc");
+#else
asm volatile("stck %0" : "=Q" (clk) : : "cc");
+#endif
return clk;
}
@@ -86,17 +90,6 @@ static inline void get_clock_ext(char *clk)
asm volatile("stcke %0" : "=Q" (*clk) : : "cc");
}
-static inline unsigned long long get_clock_fast(void)
-{
- unsigned long long clk;
-
- if (MACHINE_HAS_STCKF)
- asm volatile(".insn s,0xb27c0000,%0" : "=Q" (clk) : : "cc");
- else
- clk = get_clock();
- return clk;
-}
-
static inline unsigned long long get_clock_xt(void)
{
unsigned char clk[16];
diff --git a/arch/s390/kernel/early.c b/arch/s390/kernel/early.c
index 9475e682727f..d84181f1f5e8 100644
--- a/arch/s390/kernel/early.c
+++ b/arch/s390/kernel/early.c
@@ -374,8 +374,6 @@ static __init void detect_machine_facilities(void)
S390_lowcore.machine_flags |= MACHINE_FLAG_MVCOS;
if (test_facility(40))
S390_lowcore.machine_flags |= MACHINE_FLAG_SPP;
- if (test_facility(25))
- S390_lowcore.machine_flags |= MACHINE_FLAG_STCKF;
#endif
}
diff --git a/arch/s390/kernel/entry64.S b/arch/s390/kernel/entry64.S
index 3a633af72bae..444fd72e0787 100644
--- a/arch/s390/kernel/entry64.S
+++ b/arch/s390/kernel/entry64.S
@@ -148,6 +148,14 @@ _TIF_EXIT_SIE = (_TIF_SIGPENDING | _TIF_NEED_RESCHED | _TIF_MCCK_PENDING)
ssm __LC_RETURN_PSW
.endm
+ .macro STCK savearea
+#if defined(CONFIG_64BIT) && !defined(CONFIG_MARCH_Z900) && !defined(CONFIG_MARCH_Z990)
+ .insn s,0xb27c0000,\savearea # store clock fast
+#else
+ .insn s,0xb2050000,\savearea # store clock
+#endif
+ .endm
+
.section .kprobes.text, "ax"
/*
@@ -458,7 +466,7 @@ pgm_svcper:
* IO interrupt handler routine
*/
ENTRY(io_int_handler)
- stck __LC_INT_CLOCK
+ STCK __LC_INT_CLOCK
stpt __LC_ASYNC_ENTER_TIMER
stmg %r8,%r15,__LC_SAVE_AREA_ASYNC
lg %r10,__LC_LAST_BREAK
@@ -604,7 +612,7 @@ io_notify_resume:
* External interrupt handler routine
*/
ENTRY(ext_int_handler)
- stck __LC_INT_CLOCK
+ STCK __LC_INT_CLOCK
stpt __LC_ASYNC_ENTER_TIMER
stmg %r8,%r15,__LC_SAVE_AREA_ASYNC
lg %r10,__LC_LAST_BREAK
@@ -639,7 +647,7 @@ ENTRY(psw_idle)
larl %r1,psw_idle_lpsw+4
stg %r1,__SF_EMPTY+8(%r15)
larl %r1,.Lvtimer_max
- stck __IDLE_ENTER(%r2)
+ STCK __IDLE_ENTER(%r2)
ltr %r5,%r5
stpt __VQ_IDLE_ENTER(%r3)
jz psw_idle_lpsw
@@ -655,7 +663,7 @@ __critical_end:
* Machine check handler routines
*/
ENTRY(mcck_int_handler)
- stck __LC_MCCK_CLOCK
+ STCK __LC_MCCK_CLOCK
la %r1,4095 # revalidate r1
spt __LC_CPU_TIMER_SAVE_AREA-4095(%r1) # revalidate cpu timer
lmg %r0,%r15,__LC_GPREGS_SAVE_AREA-4095(%r1)# revalidate gprs
diff --git a/drivers/s390/cio/qdio_main.c b/drivers/s390/cio/qdio_main.c
index 19902cdc6fac..7493efafa0d5 100644
--- a/drivers/s390/cio/qdio_main.c
+++ b/drivers/s390/cio/qdio_main.c
@@ -517,7 +517,7 @@ static int get_inbound_buffer_frontier(struct qdio_q *q)
int count, stop;
unsigned char state = 0;
- q->timestamp = get_clock_fast();
+ q->timestamp = get_clock();
/*
* Don't check 128 buffers, as otherwise qdio_inbound_q_moved
@@ -788,7 +788,7 @@ static int get_outbound_buffer_frontier(struct qdio_q *q)
int count, stop;
unsigned char state = 0;
- q->timestamp = get_clock_fast();
+ q->timestamp = get_clock();
if (need_siga_sync(q))
if (((queue_type(q) != QDIO_IQDIO_QFMT) &&
--
2.34.1