#
230426 |
|
21-Jan-2012 |
kib |
Add support for the extended FPU states on amd64, both for native 64bit and 32bit ABIs. As a side-effect, it enables AVX on capable CPUs.
In particular:
- Query the CPU support for XSAVE, list of the supported extensions and the required size of FPU save area. The hw.use_xsave tunable is provided for disabling XSAVE, and hw.xsave_mask may be used to select the enabled extensions.
- Remove the FPU save area from PCB and dynamically allocate the (run-time sized) user save area on the top of the kernel stack, right above the PCB. Reorganize the thread0 PCB initialization to postpone it after BSP is queried for save area size.
- The dumppcb, stoppcbs and susppcbs now do not carry the FPU state as well. FPU state is only useful for suspend, where it is saved in dynamically allocated suspfpusave area.
- Use XSAVE and XRSTOR to save/restore FPU state, if supported and enabled.
- Define new mcontext_t flag _MC_HASFPXSTATE, indicating that mcontext_t has a valid pointer to out-of-struct extended FPU state. Signal handlers are supplied with stack-allocated fpu state. The sigreturn(2) and setcontext(2) syscall honour the flag, allowing the signal handlers to inspect and manipilate extended state in the interrupted context.
- The getcontext(2) never returns extended state, since there is no place in the fixed-sized mcontext_t to place variable-sized save area. And, since mcontext_t is embedded into ucontext_t, makes it impossible to fix in a reasonable way. Instead of extending getcontext(2) syscall, provide a sysarch(2) facility to query extended FPU state.
- Add ptrace(2) support for getting and setting extended state; while there, implement missed PT_I386_{GET,SET}XMMREGS for 32bit binaries.
- Change fpu_kern KPI to not expose struct fpu_kern_ctx layout to consumers, making it opaque. Internally, struct fpu_kern_ctx now contains a space for the extended state. Convert in-kernel consumers of fpu_kern KPI both on i386 and amd64.
First version of the support for AVX was submitted by Tim Bird <tim.bird am sony com> on behalf of Sony. This version was written from scratch.
Tested by: pho (previous version), Yamagi Burmeister <lists yamagi org> MFC after: 1 month
|
#
92383 |
|
15-Mar-2002 |
des |
Move the definition of PT_[GS]ET{,DB,FP}REGS from the MD ptrace.h to the MI ptrace.h, since all platforms define them. Keep the MD ptrace.h around for FIX_SSTEP (which is currently only needed on Alpha).
|
#
81265 |
|
08-Aug-2001 |
peter |
Zap 'ptrace(PT_READ_U, ...)' and 'ptrace(PT_WRITE_U, ...)' since they are a really nasty interface that should have been killed long ago when 'ptrace(PT_[SG]ETREGS' etc came along. The entity that they operate on (struct user) will not be around much longer since it is part-per-process and part-per-thread in a post-KSE world.
gdb does not actually use this except for the obscure 'info udot' command which does a hexdump of as much of the child's 'struct user' as it can get. It carries its own #defines so it doesn't break compiles.
|
#
21673 |
|
14-Jan-1997 |
jkh |
Make the long-awaited change from $Id$ to $FreeBSD$
This will make a number of things easier in the future, as well as (finally!) avoiding the Id-smashing problem which has plagued developers for so long.
Boy, I'm glad we're not using sup anymore. This update would have been insane otherwise.
|