Commit cd21dfcf authored by Ralf Baechle's avatar Ralf Baechle
Browse files

Fix preemption and SMP problems in the FP emulator code.

parent 63b2d2f4
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+17 −2
Original line number Diff line number Diff line
@@ -551,6 +551,14 @@ asmlinkage void do_fpe(struct pt_regs *regs, unsigned long fcr31)

		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 @@ asmlinkage void do_fpe(struct pt_regs *regs, unsigned long fcr31)
		 * 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,
			&current->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 @@ asmlinkage void do_cpu(struct pt_regs *regs)
			set_used_math();
		}

		preempt_enable();

		if (!cpu_has_fpu) {
			int sig = fpu_emulator_cop1Handler(0, regs,
						&current->thread.fpu.soft);
@@ -719,8 +736,6 @@ asmlinkage void do_cpu(struct pt_regs *regs)
				force_sig(sig, current);
		}

		preempt_enable();

		return;

	case 2:
+27 −14
Original line number Diff line number Diff line
@@ -79,7 +79,17 @@ struct mips_fpu_emulator_private fpuemuprivate;

/* 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 @@ static int cop1Emulate(struct pt_regs *xcp, struct mips_fpu_soft_struct *ctx)
			}
			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 @@ static int cop1Emulate(struct pt_regs *xcp, struct mips_fpu_soft_struct *ctx)
					(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 const unsigned char cmptab[8] = {
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 @@ static int fpux_emu(struct pt_regs *xcp, struct mips_fpu_soft_struct *ctx,
				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 @@ int fpu_emulator_cop1Handler(int xcptno, struct pt_regs *xcp,
		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)
+1 −1
Original line number Diff line number Diff line
@@ -37,7 +37,7 @@ static const unsigned table[] = {

ieee754dp ieee754dp_sqrt(ieee754dp x)
{
	struct ieee754_csr oldcsr;
	struct _ieee754_csr oldcsr;
	ieee754dp y, z, t;
	unsigned scalx, yh;
	COMPXDP;
+0 −4
Original line number Diff line number Diff line
@@ -50,10 +50,6 @@ const char *const ieee754_cname[] = {
	"SNaN",
};

/* the control status register
*/
struct ieee754_csr ieee754_csr;

/* special constants
*/

+77 −98
Original line number Diff line number Diff line
/* 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 @@ typedef union _ieee754sp {
} 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 @@ extern const char *const ieee754_cname[];

/* "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
/*
 * The control status register
 */
struct ieee754_csr {
	unsigned pad:13;
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 *)(&current->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 @@ static __inline unsigned ieee754_setrm(unsigned rm)
/*
 * 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 @@ static __inline int ieee754_cxtest(unsigned n)
/*
 * 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);
}
@@ -406,51 +403,33 @@ extern const struct ieee754sp_konst __ieee754sp_spcvals[];
#define ieee754dp_spcvals ((const ieee754dp *)__ieee754dp_spcvals)
#define ieee754sp_spcvals ((const ieee754sp *)__ieee754sp_spcvals)

/* return infinity with given sign
/*
 * 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])

/* indefinite integer value
#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])

/*
 * Indefinite integer value
 */
#define ieee754si_indef()	INT_MAX
#ifdef LONG_LONG_MAX