diff options
author | kib <kib@FreeBSD.org> | 2012-01-21 18:00:28 +0000 |
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committer | kib <kib@FreeBSD.org> | 2012-01-21 18:00:28 +0000 |
commit | 8c121450bcfa7aaf7c661baf2809bafc48c1f60f (patch) | |
tree | 4806ea5a2bf8eb5da87e290d16da86d5e5f5222f /lib/libc/amd64 | |
parent | 3572bdc783bebdf33330a1218e74826c4096ae81 (diff) | |
download | FreeBSD-src-8c121450bcfa7aaf7c661baf2809bafc48c1f60f.zip FreeBSD-src-8c121450bcfa7aaf7c661baf2809bafc48c1f60f.tar.gz |
Add API for obtaining extended machine context states that cannot be
fit into existing mcontext_t.
On i386 and amd64 do return the extended FPU states using
getcontextx(3). For other architectures, getcontextx(3) returns the
same information as getcontext(2).
Tested by: pho
MFC after: 1 month
Diffstat (limited to 'lib/libc/amd64')
-rw-r--r-- | lib/libc/amd64/gen/Makefile.inc | 2 | ||||
-rw-r--r-- | lib/libc/amd64/gen/getcontextx.c | 101 |
2 files changed, 102 insertions, 1 deletions
diff --git a/lib/libc/amd64/gen/Makefile.inc b/lib/libc/amd64/gen/Makefile.inc index 30fb05f..fb4f7f4 100644 --- a/lib/libc/amd64/gen/Makefile.inc +++ b/lib/libc/amd64/gen/Makefile.inc @@ -2,7 +2,7 @@ # $FreeBSD$ SRCS+= _setjmp.S _set_tp.c rfork_thread.S setjmp.S sigsetjmp.S \ - fabs.S \ + fabs.S getcontextx.c \ infinity.c ldexp.c makecontext.c signalcontext.c \ flt_rounds.c fpgetmask.c fpsetmask.c fpgetprec.c fpsetprec.c \ fpgetround.c fpsetround.c fpgetsticky.c diff --git a/lib/libc/amd64/gen/getcontextx.c b/lib/libc/amd64/gen/getcontextx.c new file mode 100644 index 0000000..24361bc --- /dev/null +++ b/lib/libc/amd64/gen/getcontextx.c @@ -0,0 +1,101 @@ +/* + * Copyright (c) 2011 Konstantin Belousov <kib@FreeBSD.org> + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include <sys/types.h> +#include <sys/ucontext.h> +#include <errno.h> +#include <stdarg.h> +#include <stdlib.h> +#include <machine/cpufunc.h> +#include <machine/fpu.h> +#include <machine/specialreg.h> +#include <machine/sysarch.h> + +static int xstate_sz = -1; + +size_t +__getcontextx_size(void) +{ + u_int p[4]; + + if (xstate_sz == -1) { + do_cpuid(1, p); + if ((p[2] & CPUID2_OSXSAVE) != 0) { + cpuid_count(0xd, 0x0, p); + xstate_sz = p[1] - sizeof(struct savefpu); + } else + xstate_sz = 0; + } + + return (sizeof(ucontext_t) + xstate_sz); +} + +int +__fillcontextx(char *ctx) +{ + struct amd64_get_xfpustate xfpu; + ucontext_t *ucp; + + ucp = (ucontext_t *)ctx; + if (getcontext(ucp) == -1) + return (-1); + if (xstate_sz != 0) { + xfpu.addr = (char *)(ucp + 1); + xfpu.len = xstate_sz; + if (sysarch(AMD64_GET_XFPUSTATE, &xfpu) == -1) + return (-1); + ucp->uc_mcontext.mc_xfpustate = (__register_t)xfpu.addr; + ucp->uc_mcontext.mc_xfpustate_len = xstate_sz; + ucp->uc_mcontext.mc_flags |= _MC_HASFPXSTATE; + } else { + ucp->uc_mcontext.mc_xfpustate = 0; + ucp->uc_mcontext.mc_xfpustate_len = 0; + } + return (0); +} + +__weak_reference(__getcontextx, getcontextx); + +ucontext_t * +__getcontextx(void) +{ + char *ctx; + int error; + + ctx = malloc(__getcontextx_size()); + if (ctx == NULL) + return (NULL); + if (__fillcontextx(ctx) == -1) { + error = errno; + free(ctx); + errno = error; + return (NULL); + } + return ((ucontext_t *)ctx); +} |