Fix preemption and SMP problems in the FP emulator code.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c
index 15fed02..b3ecd02 100644
--- a/arch/mips/kernel/traps.c
+++ b/arch/mips/kernel/traps.c
@@ -551,6 +551,14 @@
preempt_disable();
+#ifdef CONFIG_PREEMPT
+ if (!is_fpu_owner()) {
+ /* We might lose fpu before disabling preempt... */
+ own_fpu();
+ BUG_ON(!used_math());
+ restore_fp(current);
+ }
+#endif
/*
* Unimplemented operation exception. If we've got the full
* software emulator on-board, let's use it...
@@ -562,11 +570,18 @@
* a bit extreme for what should be an infrequent event.
*/
save_fp(current);
+ /* Ensure 'resume' not overwrite saved fp context again. */
+ lose_fpu();
+
+ preempt_enable();
/* Run the emulator */
sig = fpu_emulator_cop1Handler (0, regs,
¤t->thread.fpu.soft);
+ preempt_disable();
+
+ own_fpu(); /* Using the FPU again. */
/*
* We can't allow the emulated instruction to leave any of
* the cause bit set in $fcr31.
@@ -712,6 +727,8 @@
set_used_math();
}
+ preempt_enable();
+
if (!cpu_has_fpu) {
int sig = fpu_emulator_cop1Handler(0, regs,
¤t->thread.fpu.soft);
@@ -719,8 +736,6 @@
force_sig(sig, current);
}
- preempt_enable();
-
return;
case 2:
diff --git a/arch/mips/math-emu/cp1emu.c b/arch/mips/math-emu/cp1emu.c
index c70f25f..6fed6ce 100644
--- a/arch/mips/math-emu/cp1emu.c
+++ b/arch/mips/math-emu/cp1emu.c
@@ -79,7 +79,17 @@
/* Convert Mips rounding mode (0..3) to IEEE library modes. */
static const unsigned char ieee_rm[4] = {
- IEEE754_RN, IEEE754_RZ, IEEE754_RU, IEEE754_RD
+ [FPU_CSR_RN] = IEEE754_RN,
+ [FPU_CSR_RZ] = IEEE754_RZ,
+ [FPU_CSR_RU] = IEEE754_RU,
+ [FPU_CSR_RD] = IEEE754_RD,
+};
+/* Convert IEEE library modes to Mips rounding mode (0..3). */
+static const unsigned char mips_rm[4] = {
+ [IEEE754_RN] = FPU_CSR_RN,
+ [IEEE754_RZ] = FPU_CSR_RZ,
+ [IEEE754_RD] = FPU_CSR_RD,
+ [IEEE754_RU] = FPU_CSR_RU,
};
#if __mips >= 4
@@ -368,6 +378,7 @@
}
if (MIPSInst_RD(ir) == FPCREG_CSR) {
value = ctx->fcr31;
+ value = (value & ~0x3) | mips_rm[value & 0x3];
#ifdef CSRTRACE
printk("%p gpr[%d]<-csr=%08x\n",
(void *) (xcp->cp0_epc),
@@ -400,11 +411,10 @@
(void *) (xcp->cp0_epc),
MIPSInst_RT(ir), value);
#endif
- ctx->fcr31 = value;
- /* copy new rounding mode and
- flush bit to ieee library state! */
- ieee754_csr.nod = (ctx->fcr31 & 0x1000000) != 0;
- ieee754_csr.rm = ieee_rm[value & 0x3];
+ value &= (FPU_CSR_FLUSH | FPU_CSR_ALL_E | FPU_CSR_ALL_S | 0x03);
+ ctx->fcr31 &= ~(FPU_CSR_FLUSH | FPU_CSR_ALL_E | FPU_CSR_ALL_S | 0x03);
+ /* convert to ieee library modes */
+ ctx->fcr31 |= (value & ~0x3) | ieee_rm[value & 0x3];
}
if ((ctx->fcr31 >> 5) & ctx->fcr31 & FPU_CSR_ALL_E) {
return SIGFPE;
@@ -570,7 +580,7 @@
static ieee754##p fpemu_##p##_##name (ieee754##p r, ieee754##p s, \
ieee754##p t) \
{ \
- struct ieee754_csr ieee754_csr_save; \
+ struct _ieee754_csr ieee754_csr_save; \
s = f1 (s, t); \
ieee754_csr_save = ieee754_csr; \
s = f2 (s, r); \
@@ -699,8 +709,6 @@
rcsr |= FPU_CSR_INV_X | FPU_CSR_INV_S;
ctx->fcr31 = (ctx->fcr31 & ~FPU_CSR_ALL_X) | rcsr;
- if (ieee754_csr.nod)
- ctx->fcr31 |= 0x1000000;
if ((ctx->fcr31 >> 5) & ctx->fcr31 & FPU_CSR_ALL_E) {
/*printk ("SIGFPE: fpu csr = %08x\n",
ctx->fcr31); */
@@ -1297,12 +1305,17 @@
if (insn == 0)
xcp->cp0_epc += 4; /* skip nops */
else {
- /* Update ieee754_csr. Only relevant if we have a
- h/w FPU */
- ieee754_csr.nod = (ctx->fcr31 & 0x1000000) != 0;
- ieee754_csr.rm = ieee_rm[ctx->fcr31 & 0x3];
- ieee754_csr.cx = (ctx->fcr31 >> 12) & 0x1f;
+ /*
+ * The 'ieee754_csr' is an alias of
+ * ctx->fcr31. No need to copy ctx->fcr31 to
+ * ieee754_csr. But ieee754_csr.rm is ieee
+ * library modes. (not mips rounding mode)
+ */
+ /* convert to ieee library modes */
+ ieee754_csr.rm = ieee_rm[ieee754_csr.rm];
sig = cop1Emulate(xcp, ctx);
+ /* revert to mips rounding mode */
+ ieee754_csr.rm = mips_rm[ieee754_csr.rm];
}
if (cpu_has_fpu)
diff --git a/arch/mips/math-emu/dp_sqrt.c b/arch/mips/math-emu/dp_sqrt.c
index c35e871..032328c 100644
--- a/arch/mips/math-emu/dp_sqrt.c
+++ b/arch/mips/math-emu/dp_sqrt.c
@@ -37,7 +37,7 @@
ieee754dp ieee754dp_sqrt(ieee754dp x)
{
- struct ieee754_csr oldcsr;
+ struct _ieee754_csr oldcsr;
ieee754dp y, z, t;
unsigned scalx, yh;
COMPXDP;
diff --git a/arch/mips/math-emu/ieee754.c b/arch/mips/math-emu/ieee754.c
index f0a364a..97a752f 100644
--- a/arch/mips/math-emu/ieee754.c
+++ b/arch/mips/math-emu/ieee754.c
@@ -50,10 +50,6 @@
"SNaN",
};
-/* the control status register
-*/
-struct ieee754_csr ieee754_csr;
-
/* special constants
*/
diff --git a/arch/mips/math-emu/ieee754.h b/arch/mips/math-emu/ieee754.h
index b8772f4..5689b0c 100644
--- a/arch/mips/math-emu/ieee754.h
+++ b/arch/mips/math-emu/ieee754.h
@@ -1,13 +1,8 @@
-/* single and double precision fp ops
- * missing extended precision.
-*/
/*
* MIPS floating point support
* Copyright (C) 1994-2000 Algorithmics Ltd.
* http://www.algor.co.uk
*
- * ########################################################################
- *
* This program is free software; you can distribute it and/or modify it
* under the terms of the GNU General Public License (Version 2) as
* published by the Free Software Foundation.
@@ -21,20 +16,16 @@
* with this program; if not, write to the Free Software Foundation, Inc.,
* 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
*
- * ########################################################################
- */
-
-/**************************************************************************
* Nov 7, 2000
* Modification to allow integration with Linux kernel
*
* Kevin D. Kissell, kevink@mips.com and Carsten Langgard, carstenl@mips.com
* Copyright (C) 2000 MIPS Technologies, Inc. All rights reserved.
- *************************************************************************/
+ */
-#ifdef __KERNEL__
-/* Going from Algorithmics to Linux native environment, add this */
+#include <asm/byteorder.h>
#include <linux/types.h>
+#include <linux/sched.h>
/*
* Not very pretty, but the Linux kernel's normal va_list definition
@@ -44,18 +35,7 @@
#include <stdarg.h>
#endif
-#else
-
-/* Note that __KERNEL__ is taken to mean Linux kernel */
-
-#if #system(OpenBSD)
-#include <machine/types.h>
-#endif
-#include <machine/endian.h>
-
-#endif /* __KERNEL__ */
-
-#if (defined(BYTE_ORDER) && BYTE_ORDER == LITTLE_ENDIAN) || defined(__MIPSEL__)
+#ifdef __LITTLE_ENDIAN
struct ieee754dp_konst {
unsigned mantlo:32;
unsigned manthi:20;
@@ -86,13 +66,14 @@
} ieee754sp;
#endif
-#if (defined(BYTE_ORDER) && BYTE_ORDER == BIG_ENDIAN) || defined(__MIPSEB__)
+#ifdef __BIG_ENDIAN
struct ieee754dp_konst {
unsigned sign:1;
unsigned bexp:11;
unsigned manthi:20;
unsigned mantlo:32;
};
+
typedef union _ieee754dp {
struct ieee754dp_konst oparts;
struct {
@@ -251,93 +232,109 @@
/* "normal" comparisons
*/
-static __inline int ieee754sp_eq(ieee754sp x, ieee754sp y)
+static inline int ieee754sp_eq(ieee754sp x, ieee754sp y)
{
return ieee754sp_cmp(x, y, IEEE754_CEQ, 0);
}
-static __inline int ieee754sp_ne(ieee754sp x, ieee754sp y)
+static inline int ieee754sp_ne(ieee754sp x, ieee754sp y)
{
return ieee754sp_cmp(x, y,
IEEE754_CLT | IEEE754_CGT | IEEE754_CUN, 0);
}
-static __inline int ieee754sp_lt(ieee754sp x, ieee754sp y)
+static inline int ieee754sp_lt(ieee754sp x, ieee754sp y)
{
return ieee754sp_cmp(x, y, IEEE754_CLT, 0);
}
-static __inline int ieee754sp_le(ieee754sp x, ieee754sp y)
+static inline int ieee754sp_le(ieee754sp x, ieee754sp y)
{
return ieee754sp_cmp(x, y, IEEE754_CLT | IEEE754_CEQ, 0);
}
-static __inline int ieee754sp_gt(ieee754sp x, ieee754sp y)
+static inline int ieee754sp_gt(ieee754sp x, ieee754sp y)
{
return ieee754sp_cmp(x, y, IEEE754_CGT, 0);
}
-static __inline int ieee754sp_ge(ieee754sp x, ieee754sp y)
+static inline int ieee754sp_ge(ieee754sp x, ieee754sp y)
{
return ieee754sp_cmp(x, y, IEEE754_CGT | IEEE754_CEQ, 0);
}
-static __inline int ieee754dp_eq(ieee754dp x, ieee754dp y)
+static inline int ieee754dp_eq(ieee754dp x, ieee754dp y)
{
return ieee754dp_cmp(x, y, IEEE754_CEQ, 0);
}
-static __inline int ieee754dp_ne(ieee754dp x, ieee754dp y)
+static inline int ieee754dp_ne(ieee754dp x, ieee754dp y)
{
return ieee754dp_cmp(x, y,
IEEE754_CLT | IEEE754_CGT | IEEE754_CUN, 0);
}
-static __inline int ieee754dp_lt(ieee754dp x, ieee754dp y)
+static inline int ieee754dp_lt(ieee754dp x, ieee754dp y)
{
return ieee754dp_cmp(x, y, IEEE754_CLT, 0);
}
-static __inline int ieee754dp_le(ieee754dp x, ieee754dp y)
+static inline int ieee754dp_le(ieee754dp x, ieee754dp y)
{
return ieee754dp_cmp(x, y, IEEE754_CLT | IEEE754_CEQ, 0);
}
-static __inline int ieee754dp_gt(ieee754dp x, ieee754dp y)
+static inline int ieee754dp_gt(ieee754dp x, ieee754dp y)
{
return ieee754dp_cmp(x, y, IEEE754_CGT, 0);
}
-static __inline int ieee754dp_ge(ieee754dp x, ieee754dp y)
+static inline int ieee754dp_ge(ieee754dp x, ieee754dp y)
{
return ieee754dp_cmp(x, y, IEEE754_CGT | IEEE754_CEQ, 0);
}
-/* like strtod
-*/
+/*
+ * Like strtod
+ */
ieee754dp ieee754dp_fstr(const char *s, char **endp);
char *ieee754dp_tstr(ieee754dp x, int prec, int fmt, int af);
-/* the control status register
-*/
-struct ieee754_csr {
- unsigned pad:13;
+/*
+ * The control status register
+ */
+struct _ieee754_csr {
+#ifdef __BIG_ENDIAN
+ unsigned pad0:7;
unsigned nod:1; /* set 1 for no denormalised numbers */
- unsigned cx:5; /* exceptions this operation */
+ unsigned c:1; /* condition */
+ unsigned pad1:5;
+ unsigned cx:6; /* exceptions this operation */
unsigned mx:5; /* exception enable mask */
unsigned sx:5; /* exceptions total */
unsigned rm:2; /* current rounding mode */
+#endif
+#ifdef __LITTLE_ENDIAN
+ unsigned rm:2; /* current rounding mode */
+ unsigned sx:5; /* exceptions total */
+ unsigned mx:5; /* exception enable mask */
+ unsigned cx:6; /* exceptions this operation */
+ unsigned pad1:5;
+ unsigned c:1; /* condition */
+ unsigned nod:1; /* set 1 for no denormalised numbers */
+ unsigned pad0:7;
+#endif
};
-extern struct ieee754_csr ieee754_csr;
+#define ieee754_csr (*(struct _ieee754_csr *)(¤t->thread.fpu.soft.fcr31))
-static __inline unsigned ieee754_getrm(void)
+static inline unsigned ieee754_getrm(void)
{
return (ieee754_csr.rm);
}
-static __inline unsigned ieee754_setrm(unsigned rm)
+static inline unsigned ieee754_setrm(unsigned rm)
{
return (ieee754_csr.rm = rm);
}
@@ -345,14 +342,14 @@
/*
* get current exceptions
*/
-static __inline unsigned ieee754_getcx(void)
+static inline unsigned ieee754_getcx(void)
{
return (ieee754_csr.cx);
}
/* test for current exception condition
*/
-static __inline int ieee754_cxtest(unsigned n)
+static inline int ieee754_cxtest(unsigned n)
{
return (ieee754_csr.cx & n);
}
@@ -360,21 +357,21 @@
/*
* get sticky exceptions
*/
-static __inline unsigned ieee754_getsx(void)
+static inline unsigned ieee754_getsx(void)
{
return (ieee754_csr.sx);
}
/* clear sticky conditions
*/
-static __inline unsigned ieee754_clrsx(void)
+static inline unsigned ieee754_clrsx(void)
{
return (ieee754_csr.sx = 0);
}
/* test for sticky exception condition
*/
-static __inline int ieee754_sxtest(unsigned n)
+static inline int ieee754_sxtest(unsigned n)
{
return (ieee754_csr.sx & n);
}
@@ -406,52 +403,34 @@
#define ieee754dp_spcvals ((const ieee754dp *)__ieee754dp_spcvals)
#define ieee754sp_spcvals ((const ieee754sp *)__ieee754sp_spcvals)
-/* return infinity with given sign
-*/
-#define ieee754dp_inf(sn) \
- (ieee754dp_spcvals[IEEE754_SPCVAL_PINFINITY+(sn)])
-#define ieee754dp_zero(sn) \
- (ieee754dp_spcvals[IEEE754_SPCVAL_PZERO+(sn)])
-#define ieee754dp_one(sn) \
- (ieee754dp_spcvals[IEEE754_SPCVAL_PONE+(sn)])
-#define ieee754dp_ten(sn) \
- (ieee754dp_spcvals[IEEE754_SPCVAL_PTEN+(sn)])
-#define ieee754dp_indef() \
- (ieee754dp_spcvals[IEEE754_SPCVAL_INDEF])
-#define ieee754dp_max(sn) \
- (ieee754dp_spcvals[IEEE754_SPCVAL_PMAX+(sn)])
-#define ieee754dp_min(sn) \
- (ieee754dp_spcvals[IEEE754_SPCVAL_PMIN+(sn)])
-#define ieee754dp_mind(sn) \
- (ieee754dp_spcvals[IEEE754_SPCVAL_PMIND+(sn)])
-#define ieee754dp_1e31() \
- (ieee754dp_spcvals[IEEE754_SPCVAL_P1E31])
-#define ieee754dp_1e63() \
- (ieee754dp_spcvals[IEEE754_SPCVAL_P1E63])
+/*
+ * Return infinity with given sign
+ */
+#define ieee754dp_inf(sn) (ieee754dp_spcvals[IEEE754_SPCVAL_PINFINITY+(sn)])
+#define ieee754dp_zero(sn) (ieee754dp_spcvals[IEEE754_SPCVAL_PZERO+(sn)])
+#define ieee754dp_one(sn) (ieee754dp_spcvals[IEEE754_SPCVAL_PONE+(sn)])
+#define ieee754dp_ten(sn) (ieee754dp_spcvals[IEEE754_SPCVAL_PTEN+(sn)])
+#define ieee754dp_indef() (ieee754dp_spcvals[IEEE754_SPCVAL_INDEF])
+#define ieee754dp_max(sn) (ieee754dp_spcvals[IEEE754_SPCVAL_PMAX+(sn)])
+#define ieee754dp_min(sn) (ieee754dp_spcvals[IEEE754_SPCVAL_PMIN+(sn)])
+#define ieee754dp_mind(sn) (ieee754dp_spcvals[IEEE754_SPCVAL_PMIND+(sn)])
+#define ieee754dp_1e31() (ieee754dp_spcvals[IEEE754_SPCVAL_P1E31])
+#define ieee754dp_1e63() (ieee754dp_spcvals[IEEE754_SPCVAL_P1E63])
-#define ieee754sp_inf(sn) \
- (ieee754sp_spcvals[IEEE754_SPCVAL_PINFINITY+(sn)])
-#define ieee754sp_zero(sn) \
- (ieee754sp_spcvals[IEEE754_SPCVAL_PZERO+(sn)])
-#define ieee754sp_one(sn) \
- (ieee754sp_spcvals[IEEE754_SPCVAL_PONE+(sn)])
-#define ieee754sp_ten(sn) \
- (ieee754sp_spcvals[IEEE754_SPCVAL_PTEN+(sn)])
-#define ieee754sp_indef() \
- (ieee754sp_spcvals[IEEE754_SPCVAL_INDEF])
-#define ieee754sp_max(sn) \
- (ieee754sp_spcvals[IEEE754_SPCVAL_PMAX+(sn)])
-#define ieee754sp_min(sn) \
- (ieee754sp_spcvals[IEEE754_SPCVAL_PMIN+(sn)])
-#define ieee754sp_mind(sn) \
- (ieee754sp_spcvals[IEEE754_SPCVAL_PMIND+(sn)])
-#define ieee754sp_1e31() \
- (ieee754sp_spcvals[IEEE754_SPCVAL_P1E31])
-#define ieee754sp_1e63() \
- (ieee754sp_spcvals[IEEE754_SPCVAL_P1E63])
+#define ieee754sp_inf(sn) (ieee754sp_spcvals[IEEE754_SPCVAL_PINFINITY+(sn)])
+#define ieee754sp_zero(sn) (ieee754sp_spcvals[IEEE754_SPCVAL_PZERO+(sn)])
+#define ieee754sp_one(sn) (ieee754sp_spcvals[IEEE754_SPCVAL_PONE+(sn)])
+#define ieee754sp_ten(sn) (ieee754sp_spcvals[IEEE754_SPCVAL_PTEN+(sn)])
+#define ieee754sp_indef() (ieee754sp_spcvals[IEEE754_SPCVAL_INDEF])
+#define ieee754sp_max(sn) (ieee754sp_spcvals[IEEE754_SPCVAL_PMAX+(sn)])
+#define ieee754sp_min(sn) (ieee754sp_spcvals[IEEE754_SPCVAL_PMIN+(sn)])
+#define ieee754sp_mind(sn) (ieee754sp_spcvals[IEEE754_SPCVAL_PMIND+(sn)])
+#define ieee754sp_1e31() (ieee754sp_spcvals[IEEE754_SPCVAL_P1E31])
+#define ieee754sp_1e63() (ieee754sp_spcvals[IEEE754_SPCVAL_P1E63])
-/* indefinite integer value
-*/
+/*
+ * Indefinite integer value
+ */
#define ieee754si_indef() INT_MAX
#ifdef LONG_LONG_MAX
#define ieee754di_indef() LONG_LONG_MAX