* [PATCH V4 1/3] MIPS: bitops.h: change use of 'unsigned short' to 'int'
2012-09-05 22:32 [PATCH V4 0/3] MIPS: make funcs preempt-safe for non-mipsr2 cpus Jim Quinlan
@ 2012-09-05 22:32 ` Jim Quinlan
2012-09-05 22:32 ` [PATCH V4 2/3] MIPS: Remove irqflags.h dependency from bitops.h Jim Quinlan
` (2 subsequent siblings)
3 siblings, 0 replies; 5+ messages in thread
From: Jim Quinlan @ 2012-09-05 22:32 UTC (permalink / raw)
To: ralf, linux-mips; +Cc: ddaney.cavm, cernekee, Jim Quinlan
Signed-off-by: Jim Quinlan <jim2101024@gmail.com>
---
arch/mips/include/asm/bitops.h | 14 +++++++-------
1 files changed, 7 insertions(+), 7 deletions(-)
diff --git a/arch/mips/include/asm/bitops.h b/arch/mips/include/asm/bitops.h
index 82ad35c..455664c 100644
--- a/arch/mips/include/asm/bitops.h
+++ b/arch/mips/include/asm/bitops.h
@@ -57,7 +57,7 @@
static inline void set_bit(unsigned long nr, volatile unsigned long *addr)
{
unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
- unsigned short bit = nr & SZLONG_MASK;
+ int bit = nr & SZLONG_MASK;
unsigned long temp;
if (kernel_uses_llsc && R10000_LLSC_WAR) {
@@ -118,7 +118,7 @@ static inline void set_bit(unsigned long nr, volatile unsigned long *addr)
static inline void clear_bit(unsigned long nr, volatile unsigned long *addr)
{
unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
- unsigned short bit = nr & SZLONG_MASK;
+ int bit = nr & SZLONG_MASK;
unsigned long temp;
if (kernel_uses_llsc && R10000_LLSC_WAR) {
@@ -191,7 +191,7 @@ static inline void clear_bit_unlock(unsigned long nr, volatile unsigned long *ad
*/
static inline void change_bit(unsigned long nr, volatile unsigned long *addr)
{
- unsigned short bit = nr & SZLONG_MASK;
+ int bit = nr & SZLONG_MASK;
if (kernel_uses_llsc && R10000_LLSC_WAR) {
unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
@@ -244,7 +244,7 @@ static inline void change_bit(unsigned long nr, volatile unsigned long *addr)
static inline int test_and_set_bit(unsigned long nr,
volatile unsigned long *addr)
{
- unsigned short bit = nr & SZLONG_MASK;
+ int bit = nr & SZLONG_MASK;
unsigned long res;
smp_mb__before_llsc();
@@ -310,7 +310,7 @@ static inline int test_and_set_bit(unsigned long nr,
static inline int test_and_set_bit_lock(unsigned long nr,
volatile unsigned long *addr)
{
- unsigned short bit = nr & SZLONG_MASK;
+ int bit = nr & SZLONG_MASK;
unsigned long res;
if (kernel_uses_llsc && R10000_LLSC_WAR) {
@@ -373,7 +373,7 @@ static inline int test_and_set_bit_lock(unsigned long nr,
static inline int test_and_clear_bit(unsigned long nr,
volatile unsigned long *addr)
{
- unsigned short bit = nr & SZLONG_MASK;
+ int bit = nr & SZLONG_MASK;
unsigned long res;
smp_mb__before_llsc();
@@ -457,7 +457,7 @@ static inline int test_and_clear_bit(unsigned long nr,
static inline int test_and_change_bit(unsigned long nr,
volatile unsigned long *addr)
{
- unsigned short bit = nr & SZLONG_MASK;
+ int bit = nr & SZLONG_MASK;
unsigned long res;
smp_mb__before_llsc();
--
1.7.6
^ permalink raw reply related [flat|nested] 5+ messages in thread* [PATCH V4 2/3] MIPS: Remove irqflags.h dependency from bitops.h
2012-09-05 22:32 [PATCH V4 0/3] MIPS: make funcs preempt-safe for non-mipsr2 cpus Jim Quinlan
2012-09-05 22:32 ` [PATCH V4 1/3] MIPS: bitops.h: change use of 'unsigned short' to 'int' Jim Quinlan
@ 2012-09-05 22:32 ` Jim Quinlan
2012-09-05 22:32 ` [PATCH V4 3/3] MIPS: make funcs preempt-safe for non-mipsr2 cpus Jim Quinlan
2012-09-05 23:45 ` [PATCH V4 0/3] " David Daney
3 siblings, 0 replies; 5+ messages in thread
From: Jim Quinlan @ 2012-09-05 22:32 UTC (permalink / raw)
To: ralf, linux-mips; +Cc: ddaney.cavm, cernekee, Jim Quinlan
The "else clause" of most functions in bitops.h invoked
raw_local_irq_{save,restore}() and in doing so had a dependency on
irqflags.h. This fix moves said code to bitops.c, removing the
dependency.
Signed-off-by: Jim Quinlan <jim2101024@gmail.com>
---
arch/mips/include/asm/bitops.h | 114 +++++++------------------
arch/mips/include/asm/io.h | 1 +
arch/mips/lib/Makefile | 2 +-
arch/mips/lib/bitops.c | 179 ++++++++++++++++++++++++++++++++++++++++
4 files changed, 213 insertions(+), 83 deletions(-)
create mode 100644 arch/mips/lib/bitops.c
diff --git a/arch/mips/include/asm/bitops.h b/arch/mips/include/asm/bitops.h
index 455664c..46ac73a 100644
--- a/arch/mips/include/asm/bitops.h
+++ b/arch/mips/include/asm/bitops.h
@@ -14,7 +14,6 @@
#endif
#include <linux/compiler.h>
-#include <linux/irqflags.h>
#include <linux/types.h>
#include <asm/barrier.h>
#include <asm/byteorder.h> /* sigh ... */
@@ -44,6 +43,24 @@
#define smp_mb__before_clear_bit() smp_mb__before_llsc()
#define smp_mb__after_clear_bit() smp_llsc_mb()
+
+/*
+ * These are the "slower" versions of the functions and are in bitops.c.
+ * These functions call raw_local_irq_{save,restore}().
+ */
+void __mips_set_bit(unsigned long nr, volatile unsigned long *addr);
+void __mips_clear_bit(unsigned long nr, volatile unsigned long *addr);
+void __mips_change_bit(unsigned long nr, volatile unsigned long *addr);
+int __mips_test_and_set_bit(unsigned long nr,
+ volatile unsigned long *addr);
+int __mips_test_and_set_bit_lock(unsigned long nr,
+ volatile unsigned long *addr);
+int __mips_test_and_clear_bit(unsigned long nr,
+ volatile unsigned long *addr);
+int __mips_test_and_change_bit(unsigned long nr,
+ volatile unsigned long *addr);
+
+
/*
* set_bit - Atomically set a bit in memory
* @nr: the bit to set
@@ -92,17 +109,8 @@ static inline void set_bit(unsigned long nr, volatile unsigned long *addr)
: "=&r" (temp), "+m" (*m)
: "ir" (1UL << bit));
} while (unlikely(!temp));
- } else {
- volatile unsigned long *a = addr;
- unsigned long mask;
- unsigned long flags;
-
- a += nr >> SZLONG_LOG;
- mask = 1UL << bit;
- raw_local_irq_save(flags);
- *a |= mask;
- raw_local_irq_restore(flags);
- }
+ } else
+ __mips_set_bit(nr, addr);
}
/*
@@ -153,17 +161,8 @@ static inline void clear_bit(unsigned long nr, volatile unsigned long *addr)
: "=&r" (temp), "+m" (*m)
: "ir" (~(1UL << bit)));
} while (unlikely(!temp));
- } else {
- volatile unsigned long *a = addr;
- unsigned long mask;
- unsigned long flags;
-
- a += nr >> SZLONG_LOG;
- mask = 1UL << bit;
- raw_local_irq_save(flags);
- *a &= ~mask;
- raw_local_irq_restore(flags);
- }
+ } else
+ __mips_clear_bit(nr, addr);
}
/*
@@ -220,17 +219,8 @@ static inline void change_bit(unsigned long nr, volatile unsigned long *addr)
: "=&r" (temp), "+m" (*m)
: "ir" (1UL << bit));
} while (unlikely(!temp));
- } else {
- volatile unsigned long *a = addr;
- unsigned long mask;
- unsigned long flags;
-
- a += nr >> SZLONG_LOG;
- mask = 1UL << bit;
- raw_local_irq_save(flags);
- *a ^= mask;
- raw_local_irq_restore(flags);
- }
+ } else
+ __mips_change_bit(nr, addr);
}
/*
@@ -281,18 +271,8 @@ static inline int test_and_set_bit(unsigned long nr,
} while (unlikely(!res));
res = temp & (1UL << bit);
- } else {
- volatile unsigned long *a = addr;
- unsigned long mask;
- unsigned long flags;
-
- a += nr >> SZLONG_LOG;
- mask = 1UL << bit;
- raw_local_irq_save(flags);
- res = (mask & *a);
- *a |= mask;
- raw_local_irq_restore(flags);
- }
+ } else
+ res = __mips_test_and_set_bit(nr, addr);
smp_llsc_mb();
@@ -345,18 +325,8 @@ static inline int test_and_set_bit_lock(unsigned long nr,
} while (unlikely(!res));
res = temp & (1UL << bit);
- } else {
- volatile unsigned long *a = addr;
- unsigned long mask;
- unsigned long flags;
-
- a += nr >> SZLONG_LOG;
- mask = 1UL << bit;
- raw_local_irq_save(flags);
- res = (mask & *a);
- *a |= mask;
- raw_local_irq_restore(flags);
- }
+ } else
+ res = __mips_test_and_set_bit_lock(nr, addr);
smp_llsc_mb();
@@ -428,18 +398,8 @@ static inline int test_and_clear_bit(unsigned long nr,
} while (unlikely(!res));
res = temp & (1UL << bit);
- } else {
- volatile unsigned long *a = addr;
- unsigned long mask;
- unsigned long flags;
-
- a += nr >> SZLONG_LOG;
- mask = 1UL << bit;
- raw_local_irq_save(flags);
- res = (mask & *a);
- *a &= ~mask;
- raw_local_irq_restore(flags);
- }
+ } else
+ res = __mips_test_and_clear_bit(nr, addr);
smp_llsc_mb();
@@ -494,18 +454,8 @@ static inline int test_and_change_bit(unsigned long nr,
} while (unlikely(!res));
res = temp & (1UL << bit);
- } else {
- volatile unsigned long *a = addr;
- unsigned long mask;
- unsigned long flags;
-
- a += nr >> SZLONG_LOG;
- mask = 1UL << bit;
- raw_local_irq_save(flags);
- res = (mask & *a);
- *a ^= mask;
- raw_local_irq_restore(flags);
- }
+ } else
+ res = __mips_test_and_change_bit(nr, addr);
smp_llsc_mb();
diff --git a/arch/mips/include/asm/io.h b/arch/mips/include/asm/io.h
index 29d9c23..ff2e034 100644
--- a/arch/mips/include/asm/io.h
+++ b/arch/mips/include/asm/io.h
@@ -15,6 +15,7 @@
#include <linux/compiler.h>
#include <linux/kernel.h>
#include <linux/types.h>
+#include <linux/irqflags.h>
#include <asm/addrspace.h>
#include <asm/bug.h>
diff --git a/arch/mips/lib/Makefile b/arch/mips/lib/Makefile
index c4a82e8..a7b8937 100644
--- a/arch/mips/lib/Makefile
+++ b/arch/mips/lib/Makefile
@@ -2,7 +2,7 @@
# Makefile for MIPS-specific library files..
#
-lib-y += csum_partial.o delay.o memcpy.o memset.o \
+lib-y += bitops.o csum_partial.o delay.o memcpy.o memset.o \
strlen_user.o strncpy_user.o strnlen_user.o uncached.o
obj-y += iomap.o
diff --git a/arch/mips/lib/bitops.c b/arch/mips/lib/bitops.c
new file mode 100644
index 0000000..239a9c9
--- /dev/null
+++ b/arch/mips/lib/bitops.c
@@ -0,0 +1,179 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (c) 1994-1997, 99, 2000, 06, 07 Ralf Baechle (ralf@linux-mips.org)
+ * Copyright (c) 1999, 2000 Silicon Graphics, Inc.
+ */
+#include <linux/bitops.h>
+#include <linux/irqflags.h>
+#include <linux/export.h>
+
+
+/**
+ * __mips_set_bit - Atomically set a bit in memory. This is called by
+ * set_bit() if it cannot find a faster solution.
+ * @nr: the bit to set
+ * @addr: the address to start counting from
+ */
+void __mips_set_bit(unsigned long nr, volatile unsigned long *addr)
+{
+ volatile unsigned long *a = addr;
+ unsigned bit = nr & SZLONG_MASK;
+ unsigned long mask;
+ unsigned long flags;
+
+ a += nr >> SZLONG_LOG;
+ mask = 1UL << bit;
+ raw_local_irq_save(flags);
+ *a |= mask;
+ raw_local_irq_restore(flags);
+}
+EXPORT_SYMBOL(__mips_set_bit);
+
+
+/**
+ * __mips_clear_bit - Clears a bit in memory. This is called by clear_bit() if
+ * it cannot find a faster solution.
+ * @nr: Bit to clear
+ * @addr: Address to start counting from
+ */
+void __mips_clear_bit(unsigned long nr, volatile unsigned long *addr)
+{
+ volatile unsigned long *a = addr;
+ unsigned bit = nr & SZLONG_MASK;
+ unsigned long mask;
+ unsigned long flags;
+
+ a += nr >> SZLONG_LOG;
+ mask = 1UL << bit;
+ raw_local_irq_save(flags);
+ *a &= ~mask;
+ raw_local_irq_restore(flags);
+}
+EXPORT_SYMBOL(__mips_clear_bit);
+
+
+/**
+ * __mips_change_bit - Toggle a bit in memory. This is called by change_bit()
+ * if it cannot find a faster solution.
+ * @nr: Bit to change
+ * @addr: Address to start counting from
+ */
+void __mips_change_bit(unsigned long nr, volatile unsigned long *addr)
+{
+ volatile unsigned long *a = addr;
+ unsigned bit = nr & SZLONG_MASK;
+ unsigned long mask;
+ unsigned long flags;
+
+ a += nr >> SZLONG_LOG;
+ mask = 1UL << bit;
+ raw_local_irq_save(flags);
+ *a ^= mask;
+ raw_local_irq_restore(flags);
+}
+EXPORT_SYMBOL(__mips_change_bit);
+
+
+/**
+ * __mips_test_and_set_bit - Set a bit and return its old value. This is
+ * called by test_and_set_bit() if it cannot find a faster solution.
+ * @nr: Bit to set
+ * @addr: Address to count from
+ */
+int __mips_test_and_set_bit(unsigned long nr,
+ volatile unsigned long *addr)
+{
+ volatile unsigned long *a = addr;
+ unsigned bit = nr & SZLONG_MASK;
+ unsigned long mask;
+ unsigned long flags;
+ unsigned long res;
+
+ a += nr >> SZLONG_LOG;
+ mask = 1UL << bit;
+ raw_local_irq_save(flags);
+ res = (mask & *a);
+ *a |= mask;
+ raw_local_irq_restore(flags);
+ return res;
+}
+EXPORT_SYMBOL(__mips_test_and_set_bit);
+
+
+/**
+ * __mips_test_and_set_bit_lock - Set a bit and return its old value. This is
+ * called by test_and_set_bit_lock() if it cannot find a faster solution.
+ * @nr: Bit to set
+ * @addr: Address to count from
+ */
+int __mips_test_and_set_bit_lock(unsigned long nr,
+ volatile unsigned long *addr)
+{
+ volatile unsigned long *a = addr;
+ unsigned bit = nr & SZLONG_MASK;
+ unsigned long mask;
+ unsigned long flags;
+ unsigned long res;
+
+ a += nr >> SZLONG_LOG;
+ mask = 1UL << bit;
+ raw_local_irq_save(flags);
+ res = (mask & *a);
+ *a |= mask;
+ raw_local_irq_restore(flags);
+ return res;
+}
+EXPORT_SYMBOL(__mips_test_and_set_bit_lock);
+
+
+/**
+ * __mips_test_and_clear_bit - Clear a bit and return its old value. This is
+ * called by test_and_clear_bit() if it cannot find a faster solution.
+ * @nr: Bit to clear
+ * @addr: Address to count from
+ */
+int __mips_test_and_clear_bit(unsigned long nr, volatile unsigned long *addr)
+{
+ volatile unsigned long *a = addr;
+ unsigned bit = nr & SZLONG_MASK;
+ unsigned long mask;
+ unsigned long flags;
+ unsigned long res;
+
+ a += nr >> SZLONG_LOG;
+ mask = 1UL << bit;
+ raw_local_irq_save(flags);
+ res = (mask & *a);
+ *a &= ~mask;
+ raw_local_irq_restore(flags);
+ return res;
+}
+EXPORT_SYMBOL(__mips_test_and_clear_bit);
+
+
+/**
+ * __mips_test_and_change_bit - Change a bit and return its old value. This is
+ * called by test_and_change_bit() if it cannot find a faster solution.
+ * @nr: Bit to change
+ * @addr: Address to count from
+ */
+int __mips_test_and_change_bit(unsigned long nr, volatile unsigned long *addr)
+{
+ volatile unsigned long *a = addr;
+ unsigned bit = nr & SZLONG_MASK;
+ unsigned long mask;
+ unsigned long flags;
+ unsigned long res;
+
+ a += nr >> SZLONG_LOG;
+ mask = 1UL << bit;
+ raw_local_irq_save(flags);
+ res = (mask & *a);
+ *a ^= mask;
+ raw_local_irq_restore(flags);
+ return res;
+}
+EXPORT_SYMBOL(__mips_test_and_change_bit);
--
1.7.6
^ permalink raw reply related [flat|nested] 5+ messages in thread* [PATCH V4 3/3] MIPS: make funcs preempt-safe for non-mipsr2 cpus
2012-09-05 22:32 [PATCH V4 0/3] MIPS: make funcs preempt-safe for non-mipsr2 cpus Jim Quinlan
2012-09-05 22:32 ` [PATCH V4 1/3] MIPS: bitops.h: change use of 'unsigned short' to 'int' Jim Quinlan
2012-09-05 22:32 ` [PATCH V4 2/3] MIPS: Remove irqflags.h dependency from bitops.h Jim Quinlan
@ 2012-09-05 22:32 ` Jim Quinlan
2012-09-05 23:45 ` [PATCH V4 0/3] " David Daney
3 siblings, 0 replies; 5+ messages in thread
From: Jim Quinlan @ 2012-09-05 22:32 UTC (permalink / raw)
To: ralf, linux-mips; +Cc: ddaney.cavm, cernekee, Jim Quinlan
For non MIPSr2 processors, such as the BMIPS 5000, calls to
arch_local_irq_disable() and others may be preempted, and in doing
so a stale value may be restored to c0_status. This fix disables
preemption for such processors prior to the call and enables it
after the call.
Those functions that needed this fix have been "outlined" to
mips-atomic.c, as they are no longer good candidates for inlining.
This bug was observed in a BMIPS 5000, occuring once every few hours
in a continuous reboot test. It was traced to the write_lock_irq()
function which was being invoked in release_task() in exit.c.
By placing a number of "nops" inbetween the mfc0/mtc0 pair in
arch_local_irq_disable(), which is called by write_lock_irq(), we
were able to greatly increase the occurance of this bug. Similarly,
the application of this commit silenced the bug.
Signed-off-by: Jim Quinlan <jim2101024@gmail.com>
---
arch/mips/include/asm/irqflags.h | 207 ++++++++++++++------------------------
arch/mips/lib/Makefile | 3 +-
arch/mips/lib/mips-atomic.c | 176 ++++++++++++++++++++++++++++++++
3 files changed, 253 insertions(+), 133 deletions(-)
create mode 100644 arch/mips/lib/mips-atomic.c
diff --git a/arch/mips/include/asm/irqflags.h b/arch/mips/include/asm/irqflags.h
index 309cbcd..9f3384c 100644
--- a/arch/mips/include/asm/irqflags.h
+++ b/arch/mips/include/asm/irqflags.h
@@ -16,83 +16,13 @@
#include <linux/compiler.h>
#include <asm/hazards.h>
-__asm__(
- " .macro arch_local_irq_enable \n"
- " .set push \n"
- " .set reorder \n"
- " .set noat \n"
-#ifdef CONFIG_MIPS_MT_SMTC
- " mfc0 $1, $2, 1 # SMTC - clear TCStatus.IXMT \n"
- " ori $1, 0x400 \n"
- " xori $1, 0x400 \n"
- " mtc0 $1, $2, 1 \n"
-#elif defined(CONFIG_CPU_MIPSR2)
- " ei \n"
-#else
- " mfc0 $1,$12 \n"
- " ori $1,0x1f \n"
- " xori $1,0x1e \n"
- " mtc0 $1,$12 \n"
-#endif
- " irq_enable_hazard \n"
- " .set pop \n"
- " .endm");
+#if defined(CONFIG_CPU_MIPSR2) && !defined(CONFIG_MIPS_MT_SMTC)
-extern void smtc_ipi_replay(void);
-
-static inline void arch_local_irq_enable(void)
-{
-#ifdef CONFIG_MIPS_MT_SMTC
- /*
- * SMTC kernel needs to do a software replay of queued
- * IPIs, at the cost of call overhead on each local_irq_enable()
- */
- smtc_ipi_replay();
-#endif
- __asm__ __volatile__(
- "arch_local_irq_enable"
- : /* no outputs */
- : /* no inputs */
- : "memory");
-}
-
-
-/*
- * For cli() we have to insert nops to make sure that the new value
- * has actually arrived in the status register before the end of this
- * macro.
- * R4000/R4400 need three nops, the R4600 two nops and the R10000 needs
- * no nops at all.
- */
-/*
- * For TX49, operating only IE bit is not enough.
- *
- * If mfc0 $12 follows store and the mfc0 is last instruction of a
- * page and fetching the next instruction causes TLB miss, the result
- * of the mfc0 might wrongly contain EXL bit.
- *
- * ERT-TX49H2-027, ERT-TX49H3-012, ERT-TX49HL3-006, ERT-TX49H4-008
- *
- * Workaround: mask EXL bit of the result or place a nop before mfc0.
- */
__asm__(
" .macro arch_local_irq_disable\n"
" .set push \n"
" .set noat \n"
-#ifdef CONFIG_MIPS_MT_SMTC
- " mfc0 $1, $2, 1 \n"
- " ori $1, 0x400 \n"
- " .set noreorder \n"
- " mtc0 $1, $2, 1 \n"
-#elif defined(CONFIG_CPU_MIPSR2)
" di \n"
-#else
- " mfc0 $1,$12 \n"
- " ori $1,0x1f \n"
- " xori $1,0x1f \n"
- " .set noreorder \n"
- " mtc0 $1,$12 \n"
-#endif
" irq_disable_hazard \n"
" .set pop \n"
" .endm \n");
@@ -106,46 +36,14 @@ static inline void arch_local_irq_disable(void)
: "memory");
}
-__asm__(
- " .macro arch_local_save_flags flags \n"
- " .set push \n"
- " .set reorder \n"
-#ifdef CONFIG_MIPS_MT_SMTC
- " mfc0 \\flags, $2, 1 \n"
-#else
- " mfc0 \\flags, $12 \n"
-#endif
- " .set pop \n"
- " .endm \n");
-
-static inline unsigned long arch_local_save_flags(void)
-{
- unsigned long flags;
- asm volatile("arch_local_save_flags %0" : "=r" (flags));
- return flags;
-}
__asm__(
" .macro arch_local_irq_save result \n"
" .set push \n"
" .set reorder \n"
" .set noat \n"
-#ifdef CONFIG_MIPS_MT_SMTC
- " mfc0 \\result, $2, 1 \n"
- " ori $1, \\result, 0x400 \n"
- " .set noreorder \n"
- " mtc0 $1, $2, 1 \n"
- " andi \\result, \\result, 0x400 \n"
-#elif defined(CONFIG_CPU_MIPSR2)
" di \\result \n"
" andi \\result, 1 \n"
-#else
- " mfc0 \\result, $12 \n"
- " ori $1, \\result, 0x1f \n"
- " xori $1, 0x1f \n"
- " .set noreorder \n"
- " mtc0 $1, $12 \n"
-#endif
" irq_disable_hazard \n"
" .set pop \n"
" .endm \n");
@@ -160,61 +58,37 @@ static inline unsigned long arch_local_irq_save(void)
return flags;
}
+
__asm__(
" .macro arch_local_irq_restore flags \n"
" .set push \n"
" .set noreorder \n"
" .set noat \n"
-#ifdef CONFIG_MIPS_MT_SMTC
- "mfc0 $1, $2, 1 \n"
- "andi \\flags, 0x400 \n"
- "ori $1, 0x400 \n"
- "xori $1, 0x400 \n"
- "or \\flags, $1 \n"
- "mtc0 \\flags, $2, 1 \n"
-#elif defined(CONFIG_CPU_MIPSR2) && defined(CONFIG_IRQ_CPU)
+#if defined(CONFIG_IRQ_CPU)
/*
* Slow, but doesn't suffer from a relatively unlikely race
* condition we're having since days 1.
*/
" beqz \\flags, 1f \n"
- " di \n"
+ " di \n"
" ei \n"
"1: \n"
-#elif defined(CONFIG_CPU_MIPSR2)
+#else
/*
* Fast, dangerous. Life is fun, life is good.
*/
" mfc0 $1, $12 \n"
" ins $1, \\flags, 0, 1 \n"
" mtc0 $1, $12 \n"
-#else
- " mfc0 $1, $12 \n"
- " andi \\flags, 1 \n"
- " ori $1, 0x1f \n"
- " xori $1, 0x1f \n"
- " or \\flags, $1 \n"
- " mtc0 \\flags, $12 \n"
#endif
" irq_disable_hazard \n"
" .set pop \n"
" .endm \n");
-
static inline void arch_local_irq_restore(unsigned long flags)
{
unsigned long __tmp1;
-#ifdef CONFIG_MIPS_MT_SMTC
- /*
- * SMTC kernel needs to do a software replay of queued
- * IPIs, at the cost of branch and call overhead on each
- * local_irq_restore()
- */
- if (unlikely(!(flags & 0x0400)))
- smtc_ipi_replay();
-#endif
-
__asm__ __volatile__(
"arch_local_irq_restore\t%0"
: "=r" (__tmp1)
@@ -232,6 +106,75 @@ static inline void __arch_local_irq_restore(unsigned long 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 /* if defined(CONFIG_CPU_MIPSR2) && !defined(CONFIG_MIPS_MT_SMTC) */
+
+
+__asm__(
+ " .macro arch_local_irq_enable \n"
+ " .set push \n"
+ " .set reorder \n"
+ " .set noat \n"
+#ifdef CONFIG_MIPS_MT_SMTC
+ " mfc0 $1, $2, 1 # SMTC - clear TCStatus.IXMT \n"
+ " ori $1, 0x400 \n"
+ " xori $1, 0x400 \n"
+ " mtc0 $1, $2, 1 \n"
+#elif defined(CONFIG_CPU_MIPSR2)
+ " ei \n"
+#else
+ " mfc0 $1,$12 \n"
+ " ori $1,0x1f \n"
+ " xori $1,0x1e \n"
+ " mtc0 $1,$12 \n"
+#endif
+ " irq_enable_hazard \n"
+ " .set pop \n"
+ " .endm");
+
+extern void smtc_ipi_replay(void);
+
+static inline void arch_local_irq_enable(void)
+{
+#ifdef CONFIG_MIPS_MT_SMTC
+ /*
+ * SMTC kernel needs to do a software replay of queued
+ * IPIs, at the cost of call overhead on each local_irq_enable()
+ */
+ smtc_ipi_replay();
+#endif
+ __asm__ __volatile__(
+ "arch_local_irq_enable"
+ : /* no outputs */
+ : /* no inputs */
+ : "memory");
+}
+
+
+__asm__(
+ " .macro arch_local_save_flags flags \n"
+ " .set push \n"
+ " .set reorder \n"
+#ifdef CONFIG_MIPS_MT_SMTC
+ " mfc0 \\flags, $2, 1 \n"
+#else
+ " mfc0 \\flags, $12 \n"
+#endif
+ " .set pop \n"
+ " .endm \n");
+
+static inline unsigned long arch_local_save_flags(void)
+{
+ unsigned long flags;
+ asm volatile("arch_local_save_flags %0" : "=r" (flags));
+ return flags;
+}
+
static inline int arch_irqs_disabled_flags(unsigned long flags)
{
@@ -245,7 +188,7 @@ static inline int arch_irqs_disabled_flags(unsigned long flags)
#endif
}
-#endif
+#endif /* #ifndef __ASSEMBLY__ */
/*
* Do the CPU's IRQ-state tracing from assembly code.
diff --git a/arch/mips/lib/Makefile b/arch/mips/lib/Makefile
index a7b8937..eeddc58 100644
--- a/arch/mips/lib/Makefile
+++ b/arch/mips/lib/Makefile
@@ -3,7 +3,8 @@
#
lib-y += bitops.o csum_partial.o delay.o memcpy.o memset.o \
- strlen_user.o strncpy_user.o strnlen_user.o uncached.o
+ mips-atomic.o strlen_user.o strncpy_user.o \
+ strnlen_user.o uncached.o
obj-y += iomap.o
obj-$(CONFIG_PCI) += iomap-pci.o
diff --git a/arch/mips/lib/mips-atomic.c b/arch/mips/lib/mips-atomic.c
new file mode 100644
index 0000000..e091430
--- /dev/null
+++ b/arch/mips/lib/mips-atomic.c
@@ -0,0 +1,176 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 1994, 95, 96, 97, 98, 99, 2003 by Ralf Baechle
+ * Copyright (C) 1996 by Paul M. Antoine
+ * Copyright (C) 1999 Silicon Graphics
+ * Copyright (C) 2000 MIPS Technologies, Inc.
+ */
+#include <asm/irqflags.h>
+#include <asm/hazards.h>
+#include <linux/compiler.h>
+#include <linux/preempt.h>
+#include <linux/export.h>
+
+#if !defined(CONFIG_CPU_MIPSR2) || defined(CONFIG_MIPS_MT_SMTC)
+
+/*
+ * For cli() we have to insert nops to make sure that the new value
+ * has actually arrived in the status register before the end of this
+ * macro.
+ * R4000/R4400 need three nops, the R4600 two nops and the R10000 needs
+ * no nops at all.
+ */
+/*
+ * For TX49, operating only IE bit is not enough.
+ *
+ * If mfc0 $12 follows store and the mfc0 is last instruction of a
+ * page and fetching the next instruction causes TLB miss, the result
+ * of the mfc0 might wrongly contain EXL bit.
+ *
+ * ERT-TX49H2-027, ERT-TX49H3-012, ERT-TX49HL3-006, ERT-TX49H4-008
+ *
+ * Workaround: mask EXL bit of the result or place a nop before mfc0.
+ */
+__asm__(
+ " .macro arch_local_irq_disable\n"
+ " .set push \n"
+ " .set noat \n"
+#ifdef CONFIG_MIPS_MT_SMTC
+ " mfc0 $1, $2, 1 \n"
+ " ori $1, 0x400 \n"
+ " .set noreorder \n"
+ " mtc0 $1, $2, 1 \n"
+#elif defined(CONFIG_CPU_MIPSR2)
+ /* see irqflags.h for inline function */
+#else
+ " mfc0 $1,$12 \n"
+ " ori $1,0x1f \n"
+ " xori $1,0x1f \n"
+ " .set noreorder \n"
+ " mtc0 $1,$12 \n"
+#endif
+ " irq_disable_hazard \n"
+ " .set pop \n"
+ " .endm \n");
+
+void arch_local_irq_disable(void)
+{
+ preempt_disable();
+ __asm__ __volatile__(
+ "arch_local_irq_disable"
+ : /* no outputs */
+ : /* no inputs */
+ : "memory");
+ preempt_enable();
+}
+EXPORT_SYMBOL(arch_local_irq_disable);
+
+
+__asm__(
+ " .macro arch_local_irq_save result \n"
+ " .set push \n"
+ " .set reorder \n"
+ " .set noat \n"
+#ifdef CONFIG_MIPS_MT_SMTC
+ " mfc0 \\result, $2, 1 \n"
+ " ori $1, \\result, 0x400 \n"
+ " .set noreorder \n"
+ " mtc0 $1, $2, 1 \n"
+ " andi \\result, \\result, 0x400 \n"
+#elif defined(CONFIG_CPU_MIPSR2)
+ /* see irqflags.h for inline function */
+#else
+ " mfc0 \\result, $12 \n"
+ " ori $1, \\result, 0x1f \n"
+ " xori $1, 0x1f \n"
+ " .set noreorder \n"
+ " mtc0 $1, $12 \n"
+#endif
+ " irq_disable_hazard \n"
+ " .set pop \n"
+ " .endm \n");
+
+unsigned long arch_local_irq_save(void)
+{
+ unsigned long flags;
+ preempt_disable();
+ asm volatile("arch_local_irq_save\t%0"
+ : "=r" (flags)
+ : /* no inputs */
+ : "memory");
+ preempt_enable();
+ return flags;
+}
+EXPORT_SYMBOL(arch_local_irq_save);
+
+
+__asm__(
+ " .macro arch_local_irq_restore flags \n"
+ " .set push \n"
+ " .set noreorder \n"
+ " .set noat \n"
+#ifdef CONFIG_MIPS_MT_SMTC
+ "mfc0 $1, $2, 1 \n"
+ "andi \\flags, 0x400 \n"
+ "ori $1, 0x400 \n"
+ "xori $1, 0x400 \n"
+ "or \\flags, $1 \n"
+ "mtc0 \\flags, $2, 1 \n"
+#elif defined(CONFIG_CPU_MIPSR2) && defined(CONFIG_IRQ_CPU)
+ /* see irqflags.h for inline function */
+#elif defined(CONFIG_CPU_MIPSR2)
+ /* see irqflags.h for inline function */
+#else
+ " mfc0 $1, $12 \n"
+ " andi \\flags, 1 \n"
+ " ori $1, 0x1f \n"
+ " xori $1, 0x1f \n"
+ " or \\flags, $1 \n"
+ " mtc0 \\flags, $12 \n"
+#endif
+ " irq_disable_hazard \n"
+ " .set pop \n"
+ " .endm \n");
+
+void arch_local_irq_restore(unsigned long flags)
+{
+ unsigned long __tmp1;
+
+#ifdef CONFIG_MIPS_MT_SMTC
+ /*
+ * SMTC kernel needs to do a software replay of queued
+ * IPIs, at the cost of branch and call overhead on each
+ * local_irq_restore()
+ */
+ if (unlikely(!(flags & 0x0400)))
+ smtc_ipi_replay();
+#endif
+ preempt_disable();
+ __asm__ __volatile__(
+ "arch_local_irq_restore\t%0"
+ : "=r" (__tmp1)
+ : "0" (flags)
+ : "memory");
+ preempt_enable();
+}
+EXPORT_SYMBOL(arch_local_irq_restore);
+
+
+void __arch_local_irq_restore(unsigned long flags)
+{
+ unsigned long __tmp1;
+
+ preempt_disable();
+ __asm__ __volatile__(
+ "arch_local_irq_restore\t%0"
+ : "=r" (__tmp1)
+ : "0" (flags)
+ : "memory");
+ preempt_enable();
+}
+EXPORT_SYMBOL(__arch_local_irq_restore);
+
+#endif /* !defined(CONFIG_CPU_MIPSR2) || defined(CONFIG_MIPS_MT_SMTC) */
--
1.7.6
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