[PATCH 0/6] MIPS: Cleanups and bugfixes

[PATCH 0/6] MIPS: Cleanups and bugfixes

[Huacai Chen]

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
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This patchset is a collection of cleanups and bugfixes for Linux/MIPS.

Huacai Chen(6):
 MIPS: Cleanup the unused __arch_local_irq_restore() function.
 MIPS: Loongson-3: Improve -march option and move it to Platform.
 MIPS: Loongson-3: Fix SMP_ASK_C0COUNT IPI handler.
 MIPS: hpet: Choose a safe value for the ETIME check.
 MIPS: sync-r4k: reduce skew while synchronization.
 MIPS: Fix some missing CONFIG_CPU_MIPSR6 definitions.

Signed-off-by: Huacai Chen <chenhc@lemote.com>
---
 arch/mips/Makefile                     | 10 ----------
 arch/mips/include/asm/irqflags.h       | 30 ------------------------------
 arch/mips/include/asm/pgtable.h        |  4 ++--
 arch/mips/kernel/sync-r4k.c            | 32 ++++++++------------------------
 arch/mips/lib/mips-atomic.c            | 30 +-----------------------------
 arch/mips/loongson64/Platform          | 21 +++++++++++++++++++++
 arch/mips/loongson64/loongson-3/hpet.c | 10 +++++++---
 arch/mips/loongson64/loongson-3/smp.c  |  2 ++
 arch/mips/mm/tlbex.c                   |  2 +-
 9 files changed, 42 insertions(+), 99 deletions(-)
--
2.4.6


ÿÿÿÿÿÿ‰

[PATCH 1/6] MIPS: Cleanup the unused __arch_local_irq_restore() function

[Huacai Chen]

In history, __arch_local_irq_restore() is only used by SMTC. However,
SMTC support has been removed since 3.16, this patch remove the unused
function.

Signed-off-by: Huacai Chen <chenhc@lemote.com>
---
 arch/mips/include/asm/irqflags.h | 30 ------------------------------
 arch/mips/lib/mips-atomic.c      | 30 +-----------------------------
 2 files changed, 1 insertion(+), 59 deletions(-)

diff --git a/arch/mips/include/asm/irqflags.h b/arch/mips/include/asm/irqflags.h
index e7b138b..65c351e 100644
--- a/arch/mips/include/asm/irqflags.h
+++ b/arch/mips/include/asm/irqflags.h
@@ -84,41 +84,11 @@ static inline void arch_local_irq_restore(unsigned long flags)
 	: "memory");
 }
 
-static inline void __arch_local_irq_restore(unsigned long flags)
-{
-	__asm__ __volatile__(
-	"	.set	push						\n"
-	"	.set	noreorder					\n"
-	"	.set	noat						\n"
-#if defined(CONFIG_IRQ_MIPS_CPU)
-	/*
-	 * Slow, but doesn't suffer from a relatively unlikely race
-	 * condition we're having since days 1.
-	 */
-	"	beqz	%[flags], 1f					\n"
-	"	di							\n"
-	"	ei							\n"
-	"1:								\n"
-#else
-	/*
-	 * Fast, dangerous.  Life is fun, life is good.
-	 */
-	"	mfc0	$1, $12						\n"
-	"	ins	$1, %[flags], 0, 1				\n"
-	"	mtc0	$1, $12						\n"
-#endif
-	"	" __stringify(__irq_disable_hazard) "			\n"
-	"	.set	pop						\n"
-	: [flags] "=r" (flags)
-	: "0" (flags)
-	: "memory");
-}
 #else
 /* Functions that require preempt_{dis,en}able() are in mips-atomic.c */
 void arch_local_irq_disable(void);
 unsigned long arch_local_irq_save(void);
 void arch_local_irq_restore(unsigned long flags);
-void __arch_local_irq_restore(unsigned long flags);
 #endif /* CONFIG_CPU_MIPSR2 || CONFIG_CPU_MIPSR6 */
 
 static inline void arch_local_irq_enable(void)
diff --git a/arch/mips/lib/mips-atomic.c b/arch/mips/lib/mips-atomic.c
index 272af8a..5530070 100644
--- a/arch/mips/lib/mips-atomic.c
+++ b/arch/mips/lib/mips-atomic.c
@@ -57,7 +57,6 @@ notrace void arch_local_irq_disable(void)
 }
 EXPORT_SYMBOL(arch_local_irq_disable);
 
-
 notrace unsigned long arch_local_irq_save(void)
 {
 	unsigned long flags;
@@ -111,31 +110,4 @@ notrace void arch_local_irq_restore(unsigned long flags)
 }
 EXPORT_SYMBOL(arch_local_irq_restore);
 
-
-notrace void __arch_local_irq_restore(unsigned long flags)
-{
-	unsigned long __tmp1;
-
-	preempt_disable();
-
-	__asm__ __volatile__(
-	"	.set	push						\n"
-	"	.set	noreorder					\n"
-	"	.set	noat						\n"
-	"	mfc0	$1, $12						\n"
-	"	andi	%[flags], 1					\n"
-	"	ori	$1, 0x1f					\n"
-	"	xori	$1, 0x1f					\n"
-	"	or	%[flags], $1					\n"
-	"	mtc0	%[flags], $12					\n"
-	"	" __stringify(__irq_disable_hazard) "			\n"
-	"	.set	pop						\n"
-	: [flags] "=r" (__tmp1)
-	: "0" (flags)
-	: "memory");
-
-	preempt_enable();
-}
-EXPORT_SYMBOL(__arch_local_irq_restore);
-
-#endif /* !CONFIG_CPU_MIPSR2 */
+#endif /* !CONFIG_CPU_MIPSR2 && !CONFIG_CPU_MIPSR6 */
-- 
2.4.6

[PATCH 2/6] MIPS: Loongson-3: Improve -march option and move it to Platform

[Huacai Chen]

If GCC >= 4.9 and Binutils >=2.25, we use -march=loongson3a, otherwise
we use -march=mips64r2, this can slightly improve performance. Besides,
arch/mips/loongson64/Platform is a better location rather than arch/
mips/Makefile.

Signed-off-by: Huacai Chen <chenhc@lemote.com>
---
 arch/mips/Makefile            | 10 ----------
 arch/mips/loongson64/Platform | 21 +++++++++++++++++++++
 2 files changed, 21 insertions(+), 10 deletions(-)

diff --git a/arch/mips/Makefile b/arch/mips/Makefile
index 3f70ba5..e78d60d 100644
--- a/arch/mips/Makefile
+++ b/arch/mips/Makefile
@@ -166,16 +166,6 @@ cflags-$(CONFIG_CPU_CAVIUM_OCTEON) += -Wa,-march=octeon
 endif
 cflags-$(CONFIG_CAVIUM_CN63XXP1) += -Wa,-mfix-cn63xxp1
 cflags-$(CONFIG_CPU_BMIPS)	+= -march=mips32 -Wa,-mips32 -Wa,--trap
-#
-# binutils from v2.25 on and gcc starting from v4.9.0 treat -march=loongson3a
-# as MIPS64 R1; older versions as just R1.  This leaves the possibility open
-# that GCC might generate R2 code for -march=loongson3a which then is rejected
-# by GAS.  The cc-option can't probe for this behaviour so -march=loongson3a
-# can't easily be used safely within the kbuild framework.
-#
-cflags-$(CONFIG_CPU_LOONGSON3)  +=					\
-	$(call cc-option,-march=mips64r2,-mips64r2 -U_MIPS_ISA -D_MIPS_ISA=_MIPS_ISA_MIPS64) \
-	-Wa,-mips64r2 -Wa,--trap
 
 cflags-$(CONFIG_CPU_R4000_WORKAROUNDS)	+= $(call cc-option,-mfix-r4000,)
 cflags-$(CONFIG_CPU_R4400_WORKAROUNDS)	+= $(call cc-option,-mfix-r4400,)
diff --git a/arch/mips/loongson64/Platform b/arch/mips/loongson64/Platform
index 2e48e83..85d8089 100644
--- a/arch/mips/loongson64/Platform
+++ b/arch/mips/loongson64/Platform
@@ -22,6 +22,27 @@ ifdef CONFIG_CPU_LOONGSON2F_WORKAROUNDS
   endif
 endif
 
+cflags-$(CONFIG_CPU_LOONGSON3)	+= -Wa,--trap
+#
+# binutils from v2.25 on and gcc starting from v4.9.0 treat -march=loongson3a
+# as MIPS64 R2; older versions as just R1.  This leaves the possibility open
+# that GCC might generate R2 code for -march=loongson3a which then is rejected
+# by GAS.  The cc-option can't probe for this behaviour so -march=loongson3a
+# can't easily be used safely within the kbuild framework.
+#
+ifeq ($(call cc-ifversion, -ge, 0409, y), y)
+  ifeq ($(call ld-ifversion, -ge, 22500000, y), y)
+    cflags-$(CONFIG_CPU_LOONGSON3)  += \
+      $(call cc-option,-march=loongson3a -U_MIPS_ISA -D_MIPS_ISA=_MIPS_ISA_MIPS64)
+  else
+    cflags-$(CONFIG_CPU_LOONGSON3)  += \
+      $(call cc-option,-march=mips64r2,-mips64r2 -U_MIPS_ISA -D_MIPS_ISA=_MIPS_ISA_MIPS64)
+  endif
+else
+    cflags-$(CONFIG_CPU_LOONGSON3)  += \
+      $(call cc-option,-march=mips64r2,-mips64r2 -U_MIPS_ISA -D_MIPS_ISA=_MIPS_ISA_MIPS64)
+endif
+
 #
 # Loongson Machines' Support
 #
-- 
2.4.6

[PATCH 3/6] MIPS: Loongson-3: Fix SMP_ASK_C0COUNT IPI handler

When Core-0 handle SMP_ASK_C0COUNT IPI, we should make other cores to
see the result as soon as possible (especially when Store-Fill-Buffer
is enabled). Otherwise, C0_Count syncronization makes no sense.

BTW, there is a corner should be avoid: C0_Count of Core-0 is really 0.

Cc: <stable@vger.kernel.org>
Signed-off-by: Huacai Chen <chenhc@lemote.com>
---
 arch/mips/loongson64/loongson-3/smp.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/mips/loongson64/loongson-3/smp.c b/arch/mips/loongson64/loongson-3/smp.c
index 1a4738a..55d0f5f 100644
--- a/arch/mips/loongson64/loongson-3/smp.c
+++ b/arch/mips/loongson64/loongson-3/smp.c
@@ -275,8 +275,10 @@ void loongson3_ipi_interrupt(struct pt_regs *regs)
 	if (action & SMP_ASK_C0COUNT) {
 		BUG_ON(cpu != 0);
 		c0count = read_c0_count();
+		c0count = c0count ? c0count : 1;
 		for (i = 1; i < num_possible_cpus(); i++)
 			per_cpu(core0_c0count, i) = c0count;
+		__wbflush(); /* Let others see the result ASAP */
 	}
 }
 
-- 
2.4.6

[PATCH 3/6] MIPS: Loongson-3: Fix SMP_ASK_C0COUNT IPI handler

[Huacai Chen]

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
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When Core-0 handle SMP_ASK_C0COUNT IPI, we should make other cores to
see the result as soon as possible (especially when Store-Fill-Buffer
is enabled). Otherwise, C0_Count syncronization makes no sense.

BTW, there is a corner should be avoid: C0_Count of Core-0 is really 0.

Cc: <stable@vger.kernel.org>
Signed-off-by: Huacai Chen <chenhc@lemote.com>
---
 arch/mips/loongson64/loongson-3/smp.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/mips/loongson64/loongson-3/smp.c b/arch/mips/loongson64/loongson-3/smp.c
index 1a4738a..55d0f5f 100644
--- a/arch/mips/loongson64/loongson-3/smp.c
+++ b/arch/mips/loongson64/loongson-3/smp.c
@@ -275,8 +275,10 @@ void loongson3_ipi_interrupt(struct pt_regs *regs)
 	if (action & SMP_ASK_C0COUNT) {
 		BUG_ON(cpu != 0);
 		c0count = read_c0_count();
+		c0count = c0count ? c0count : 1;
 		for (i = 1; i < num_possible_cpus(); i++)
 			per_cpu(core0_c0count, i) = c0count;
+		__wbflush(); /* Let others see the result ASAP */
 	}
 }
 
-- 
2.4.6



ÿÿ		

[PATCH 3/6] MIPS: Loongson-3: Fix SMP_ASK_C0COUNT IPI handler

[Huacai Chen]

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain, Size: 1006 bytes --]

When Core-0 handle SMP_ASK_C0COUNT IPI, we should make other cores to
see the result as soon as possible (especially when Store-Fill-Buffer
is enabled). Otherwise, C0_Count syncronization makes no sense.

BTW, there is a corner should be avoid: C0_Count of Core-0 is really 0.

Cc: <stable@vger.kernel.org>
Signed-off-by: Huacai Chen <chenhc@lemote.com>
---
 arch/mips/loongson64/loongson-3/smp.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/mips/loongson64/loongson-3/smp.c b/arch/mips/loongson64/loongson-3/smp.c
index 1a4738a..55d0f5f 100644
--- a/arch/mips/loongson64/loongson-3/smp.c
+++ b/arch/mips/loongson64/loongson-3/smp.c
@@ -275,8 +275,10 @@ void loongson3_ipi_interrupt(struct pt_regs *regs)
 	if (action & SMP_ASK_C0COUNT) {
 		BUG_ON(cpu != 0);
 		c0count = read_c0_count();
+		c0count = c0count ? c0count : 1;
 		for (i = 1; i < num_possible_cpus(); i++)
 			per_cpu(core0_c0count, i) = c0count;
+		__wbflush(); /* Let others see the result ASAP */
 	}
 }
 
-- 
2.4.6



ÿÿ		

[PATCH 4/6] MIPS: hpet: Choose a safe value for the ETIME check

[Huacai Chen]

This patch is borrowed from x86 hpet driver and explaind below:

Due to the overly intelligent design of HPETs, we need to workaround
the problem that the compare value which we write is already behind
the actual counter value at the point where the value hits the real
compare register. This happens for two reasons:

1) We read out the counter, add the delta and write the result to the
   compare register. When a NMI hits between the read out and the write
   then the counter can be ahead of the event already.

2) The write to the compare register is delayed by up to two HPET
   cycles in AMD chipsets.

We can work around this by reading back the compare register to make
sure that the written value has hit the hardware. But that is bad
performance wise for the normal case where the event is far enough in
the future.

As we already know that the write can be delayed by up to two cycles
we can avoid the read back of the compare register completely if we
make the decision whether the delta has elapsed already or not based
on the following calculation:

  cmp = event - actual_count;

If cmp is less than 64 HPET clock cycles, then we decide that the event
has happened already and return -ETIME. That covers the above #1 and #2
problems which would cause a wait for HPET wraparound (~306 seconds).

Cc: <stable@vger.kernel.org>
Signed-off-by: Huacai Chen <chenhc@lemote.com>
---
 arch/mips/loongson64/loongson-3/hpet.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/arch/mips/loongson64/loongson-3/hpet.c b/arch/mips/loongson64/loongson-3/hpet.c
index bf9f1a7..a2631a5 100644
--- a/arch/mips/loongson64/loongson-3/hpet.c
+++ b/arch/mips/loongson64/loongson-3/hpet.c
@@ -13,6 +13,9 @@
 #define SMBUS_PCI_REG64		0x64
 #define SMBUS_PCI_REGB4		0xb4
 
+#define HPET_MIN_CYCLES		64
+#define HPET_MIN_PROG_DELTA	(HPET_MIN_CYCLES + (HPET_MIN_CYCLES >> 1))
+
 static DEFINE_SPINLOCK(hpet_lock);
 DEFINE_PER_CPU(struct clock_event_device, hpet_clockevent_device);
 
@@ -161,8 +164,9 @@ static int hpet_next_event(unsigned long delta,
 	cnt += delta;
 	hpet_write(HPET_T0_CMP, cnt);
 
-	res = ((int)(hpet_read(HPET_COUNTER) - cnt) > 0) ? -ETIME : 0;
-	return res;
+	res = (int)(cnt - hpet_read(HPET_COUNTER));
+
+	return res < HPET_MIN_CYCLES ? -ETIME : 0;
 }
 
 static irqreturn_t hpet_irq_handler(int irq, void *data)
@@ -237,7 +241,7 @@ void __init setup_hpet_timer(void)
 	cd->cpumask = cpumask_of(cpu);
 	clockevent_set_clock(cd, HPET_FREQ);
 	cd->max_delta_ns = clockevent_delta2ns(0x7fffffff, cd);
-	cd->min_delta_ns = 5000;
+	cd->min_delta_ns = clockevent_delta2ns(HPET_MIN_PROG_DELTA, cd);
 
 	clockevents_register_device(cd);
 	setup_irq(HPET_T0_IRQ, &hpet_irq);
-- 
2.4.6

[PATCH 4/6] MIPS: hpet: Choose a safe value for the ETIME check

[Huacai Chen]

This patch is borrowed from x86 hpet driver and explaind below:

Due to the overly intelligent design of HPETs, we need to workaround
the problem that the compare value which we write is already behind
the actual counter value at the point where the value hits the real
compare register. This happens for two reasons:

1) We read out the counter, add the delta and write the result to the
   compare register. When a NMI hits between the read out and the write
   then the counter can be ahead of the event already.

2) The write to the compare register is delayed by up to two HPET
   cycles in AMD chipsets.

We can work around this by reading back the compare register to make
sure that the written value has hit the hardware. But that is bad
performance wise for the normal case where the event is far enough in
the future.

As we already know that the write can be delayed by up to two cycles
we can avoid the read back of the compare register completely if we
make the decision whether the delta has elapsed already or not based
on the following calculation:

  cmp = event - actual_count;

If cmp is less than 64 HPET clock cycles, then we decide that the event
has happened already and return -ETIME. That covers the above #1 and #2
problems which would cause a wait for HPET wraparound (~306 seconds).

Cc: <stable@vger.kernel.org>
Signed-off-by: Huacai Chen <chenhc@lemote.com>
---
 arch/mips/loongson64/loongson-3/hpet.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/arch/mips/loongson64/loongson-3/hpet.c b/arch/mips/loongson64/loongson-3/hpet.c
index bf9f1a7..a2631a5 100644
--- a/arch/mips/loongson64/loongson-3/hpet.c
+++ b/arch/mips/loongson64/loongson-3/hpet.c
@@ -13,6 +13,9 @@
 #define SMBUS_PCI_REG64		0x64
 #define SMBUS_PCI_REGB4		0xb4
 
+#define HPET_MIN_CYCLES		64
+#define HPET_MIN_PROG_DELTA	(HPET_MIN_CYCLES + (HPET_MIN_CYCLES >> 1))
+
 static DEFINE_SPINLOCK(hpet_lock);
 DEFINE_PER_CPU(struct clock_event_device, hpet_clockevent_device);
 
@@ -161,8 +164,9 @@ static int hpet_next_event(unsigned long delta,
 	cnt += delta;
 	hpet_write(HPET_T0_CMP, cnt);
 
-	res = ((int)(hpet_read(HPET_COUNTER) - cnt) > 0) ? -ETIME : 0;
-	return res;
+	res = (int)(cnt - hpet_read(HPET_COUNTER));
+
+	return res < HPET_MIN_CYCLES ? -ETIME : 0;
 }
 
 static irqreturn_t hpet_irq_handler(int irq, void *data)
@@ -237,7 +241,7 @@ void __init setup_hpet_timer(void)
 	cd->cpumask = cpumask_of(cpu);
 	clockevent_set_clock(cd, HPET_FREQ);
 	cd->max_delta_ns = clockevent_delta2ns(0x7fffffff, cd);
-	cd->min_delta_ns = 5000;
+	cd->min_delta_ns = clockevent_delta2ns(HPET_MIN_PROG_DELTA, cd);
 
 	clockevents_register_device(cd);
 	setup_irq(HPET_T0_IRQ, &hpet_irq);
-- 
2.4.6

[PATCH 5/6] MIPS: sync-r4k: reduce skew while synchronization

[Huacai Chen]

While synchronization, count register will go backwards for the master.
If synchronise_count_master() runs before synchronise_count_slave(),
skew becomes even more. The skew is very harmful for CPU hotplug (CPU0
do synchronization with CPU1, then CPU0 do synchronization with CPU2
and CPU0's count goes backwards, so it will be out of sync with CPU1).

After the commit cf9bfe55f24973a8f40e2 (MIPS: Synchronize MIPS count one
CPU at a time), we needn't evaluate count_reference at the beginning of
synchronise_count_master() any more. Thus, we evaluate the initcount (It
seems like count_reference is redundant) in the 2nd loop. Since we write
the count register in the last loop, we don't need additional barriers
(the existing memory barriers are enough).

Moreover, I think we loop 3 times is enough to get a primed instruction
cache, this can also get less skew than looping 5 times.

Comments are also updated in this patch.

Signed-off-by: Huacai Chen <chenhc@lemote.com>
---
 arch/mips/kernel/sync-r4k.c | 32 ++++++++------------------------
 1 file changed, 8 insertions(+), 24 deletions(-)

diff --git a/arch/mips/kernel/sync-r4k.c b/arch/mips/kernel/sync-r4k.c
index 2242bdd..4472a7f 100644
--- a/arch/mips/kernel/sync-r4k.c
+++ b/arch/mips/kernel/sync-r4k.c
@@ -17,35 +17,23 @@
 #include <asm/barrier.h>
 #include <asm/mipsregs.h>
 
-static atomic_t count_start_flag = ATOMIC_INIT(0);
+static unsigned int initcount = 0;
 static atomic_t count_count_start = ATOMIC_INIT(0);
 static atomic_t count_count_stop = ATOMIC_INIT(0);
-static atomic_t count_reference = ATOMIC_INIT(0);
 
 #define COUNTON 100
-#define NR_LOOPS 5
+#define NR_LOOPS 3
 
 void synchronise_count_master(int cpu)
 {
 	int i;
 	unsigned long flags;
-	unsigned int initcount;
 
 	printk(KERN_INFO "Synchronize counters for CPU %u: ", cpu);
 
 	local_irq_save(flags);
 
 	/*
-	 * Notify the slaves that it's time to start
-	 */
-	atomic_set(&count_reference, read_c0_count());
-	atomic_set(&count_start_flag, cpu);
-	smp_wmb();
-
-	/* Count will be initialised to current timer for all CPU's */
-	initcount = read_c0_count();
-
-	/*
 	 * We loop a few times to get a primed instruction cache,
 	 * then the last pass is more or less synchronised and
 	 * the master and slaves each set their cycle counters to a known
@@ -63,9 +51,13 @@ void synchronise_count_master(int cpu)
 		atomic_set(&count_count_stop, 0);
 		smp_wmb();
 
-		/* this lets the slaves write their count register */
+		/* Let the slave writes its count register */
 		atomic_inc(&count_count_start);
 
+		/* Count will be initialised to current timer */
+		if (i == 1)
+			initcount = read_c0_count();
+
 		/*
 		 * Everyone initialises count in the last loop:
 		 */
@@ -73,7 +65,7 @@ void synchronise_count_master(int cpu)
 			write_c0_count(initcount);
 
 		/*
-		 * Wait for all slaves to leave the synchronization point:
+		 * Wait for slave to leave the synchronization point:
 		 */
 		while (atomic_read(&count_count_stop) != 1)
 			mb();
@@ -83,7 +75,6 @@ void synchronise_count_master(int cpu)
 	}
 	/* Arrange for an interrupt in a short while */
 	write_c0_compare(read_c0_count() + COUNTON);
-	atomic_set(&count_start_flag, 0);
 
 	local_irq_restore(flags);
 
@@ -98,19 +89,12 @@ void synchronise_count_master(int cpu)
 void synchronise_count_slave(int cpu)
 {
 	int i;
-	unsigned int initcount;
 
 	/*
 	 * Not every cpu is online at the time this gets called,
 	 * so we first wait for the master to say everyone is ready
 	 */
 
-	while (atomic_read(&count_start_flag) != cpu)
-		mb();
-
-	/* Count will be initialised to next expire for all CPU's */
-	initcount = atomic_read(&count_reference);
-
 	for (i = 0; i < NR_LOOPS; i++) {
 		atomic_inc(&count_count_start);
 		while (atomic_read(&count_count_start) != 2)
-- 
2.4.6

[PATCH 6/6] MIPS: Fix some missing CONFIG_CPU_MIPSR6 definitions

[Huacai Chen]

Commit be0c37c985eddc4 (MIPS: Rearrange PTE bits into fixed positions.)
defines fixed PTE bits for MIPS R2. Then, commit d7b631419b3d230a4d383
(MIPS: pgtable-bits: Fix XPA damage to R6 definitions.) adds the MIPS
R6 definitions in the same way as MIPS R2. But some R6 definitions in
the later commit is missing, so in this patch I fix that.

Cc: <stable@vger.kernel.org>
Signed-off-by: Huacai Chen <chenhc@lemote.com>
---
 arch/mips/include/asm/pgtable.h | 4 ++--
 arch/mips/mm/tlbex.c            | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/mips/include/asm/pgtable.h b/arch/mips/include/asm/pgtable.h
index 8957f15..18826aa 100644
--- a/arch/mips/include/asm/pgtable.h
+++ b/arch/mips/include/asm/pgtable.h
@@ -353,7 +353,7 @@ static inline pte_t pte_mkdirty(pte_t pte)
 static inline pte_t pte_mkyoung(pte_t pte)
 {
 	pte_val(pte) |= _PAGE_ACCESSED;
-#ifdef CONFIG_CPU_MIPSR2
+#if defined(CONFIG_CPU_MIPSR2) || defined(CONFIG_CPU_MIPSR6)
 	if (!(pte_val(pte) & _PAGE_NO_READ))
 		pte_val(pte) |= _PAGE_SILENT_READ;
 	else
@@ -560,7 +560,7 @@ static inline pmd_t pmd_mkyoung(pmd_t pmd)
 {
 	pmd_val(pmd) |= _PAGE_ACCESSED;
 
-#ifdef CONFIG_CPU_MIPSR2
+#if defined(CONFIG_CPU_MIPSR2) || defined(CONFIG_CPU_MIPSR6)
 	if (!(pmd_val(pmd) & _PAGE_NO_READ))
 		pmd_val(pmd) |= _PAGE_SILENT_READ;
 	else
diff --git a/arch/mips/mm/tlbex.c b/arch/mips/mm/tlbex.c
index 32e0be2..29f73e0 100644
--- a/arch/mips/mm/tlbex.c
+++ b/arch/mips/mm/tlbex.c
@@ -242,7 +242,7 @@ static void output_pgtable_bits_defines(void)
 	pr_define("_PAGE_HUGE_SHIFT %d\n", _PAGE_HUGE_SHIFT);
 	pr_define("_PAGE_SPLITTING_SHIFT %d\n", _PAGE_SPLITTING_SHIFT);
 #endif
-#ifdef CONFIG_CPU_MIPSR2
+#if defined(CONFIG_CPU_MIPSR2) || defined(CONFIG_CPU_MIPSR6)
 	if (cpu_has_rixi) {
 #ifdef _PAGE_NO_EXEC_SHIFT
 		pr_define("_PAGE_NO_EXEC_SHIFT %d\n", _PAGE_NO_EXEC_SHIFT);
-- 
2.4.6

[PATCH 6/6] MIPS: Fix some missing CONFIG_CPU_MIPSR6 definitions

[Huacai Chen]

Commit be0c37c985eddc4 (MIPS: Rearrange PTE bits into fixed positions.)
defines fixed PTE bits for MIPS R2. Then, commit d7b631419b3d230a4d383
(MIPS: pgtable-bits: Fix XPA damage to R6 definitions.) adds the MIPS
R6 definitions in the same way as MIPS R2. But some R6 definitions in
the later commit is missing, so in this patch I fix that.

Cc: <stable@vger.kernel.org>
Signed-off-by: Huacai Chen <chenhc@lemote.com>
---
 arch/mips/include/asm/pgtable.h | 4 ++--
 arch/mips/mm/tlbex.c            | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/mips/include/asm/pgtable.h b/arch/mips/include/asm/pgtable.h
index 8957f15..18826aa 100644
--- a/arch/mips/include/asm/pgtable.h
+++ b/arch/mips/include/asm/pgtable.h
@@ -353,7 +353,7 @@ static inline pte_t pte_mkdirty(pte_t pte)
 static inline pte_t pte_mkyoung(pte_t pte)
 {
 	pte_val(pte) |= _PAGE_ACCESSED;
-#ifdef CONFIG_CPU_MIPSR2
+#if defined(CONFIG_CPU_MIPSR2) || defined(CONFIG_CPU_MIPSR6)
 	if (!(pte_val(pte) & _PAGE_NO_READ))
 		pte_val(pte) |= _PAGE_SILENT_READ;
 	else
@@ -560,7 +560,7 @@ static inline pmd_t pmd_mkyoung(pmd_t pmd)
 {
 	pmd_val(pmd) |= _PAGE_ACCESSED;
 
-#ifdef CONFIG_CPU_MIPSR2
+#if defined(CONFIG_CPU_MIPSR2) || defined(CONFIG_CPU_MIPSR6)
 	if (!(pmd_val(pmd) & _PAGE_NO_READ))
 		pmd_val(pmd) |= _PAGE_SILENT_READ;
 	else
diff --git a/arch/mips/mm/tlbex.c b/arch/mips/mm/tlbex.c
index 32e0be2..29f73e0 100644
--- a/arch/mips/mm/tlbex.c
+++ b/arch/mips/mm/tlbex.c
@@ -242,7 +242,7 @@ static void output_pgtable_bits_defines(void)
 	pr_define("_PAGE_HUGE_SHIFT %d\n", _PAGE_HUGE_SHIFT);
 	pr_define("_PAGE_SPLITTING_SHIFT %d\n", _PAGE_SPLITTING_SHIFT);
 #endif
-#ifdef CONFIG_CPU_MIPSR2
+#if defined(CONFIG_CPU_MIPSR2) || defined(CONFIG_CPU_MIPSR6)
 	if (cpu_has_rixi) {
 #ifdef _PAGE_NO_EXEC_SHIFT
 		pr_define("_PAGE_NO_EXEC_SHIFT %d\n", _PAGE_NO_EXEC_SHIFT);
-- 
2.4.6

Re: [PATCH 6/6] MIPS: Fix some missing CONFIG_CPU_MIPSR6 definitions

[Sergei Shtylyov]

Hello.

On 1/5/2016 8:59 AM, Huacai Chen wrote:

> Commit be0c37c985eddc4 (MIPS: Rearrange PTE bits into fixed positions.)
> defines fixed PTE bits for MIPS R2. Then, commit d7b631419b3d230a4d383
> (MIPS: pgtable-bits: Fix XPA damage to R6 definitions.) adds the MIPS
> R6 definitions in the same way as MIPS R2. But some R6 definitions in
> the later commit is missing, so in this patch I fix that.

    You're adding #ifdef's, not definitions.

> Cc: <stable@vger.kernel.org>
> Signed-off-by: Huacai Chen <chenhc@lemote.com>
[...]

MBR, Sergei