freebsd-dev/sys/amd64/linux32
Konstantin Belousov a2622e5dc2 Restore the segment registers and segment base MSRs for amd64 syscall
return path only when neither thread was context switched while
executing syscall code nor syscall explicitely modified LDT or MSRs.

Save segment registers in trap handlers before interrupts are enabled,
to not allow context switches to happen before registers are saved.
Use separated byte in pcb for indication of fast/full return, since
pcb_flags are not synchronized with context switches.

The change puts back syscall microbenchmark numbers that were slowed
down after commit of the support for LDT on amd64.

Reviewed by:	jeff
Tested (and tested, and tested ...) by:	pho
Approved by:	re (kensmith)
2009-07-09 09:34:11 +00:00
..
linux32_dummy.c Implement robust futexes. Most of the code is modelled after 2008-05-13 20:01:27 +00:00
linux32_genassym.c Segment registers are stored in the uc_mcontext member of the struct 2008-09-07 16:39:21 +00:00
linux32_ipc64.h
linux32_locore.s Save and restore segment registers on amd64 when entering and leaving 2009-04-01 13:09:26 +00:00
linux32_machdep.c Save and restore segment registers on amd64 when entering and leaving 2009-04-01 13:09:26 +00:00
linux32_proto.h Regenerate 2008-11-29 14:57:58 +00:00
linux32_support.s Move futex support code from <arch>/support.s into linux compat directory. 2007-05-23 08:33:06 +00:00
linux32_syscall.h Regenerate 2008-11-29 14:57:58 +00:00
linux32_sysent.c Regenerate generated syscall files following changes to struct sysent in 2009-06-01 16:14:38 +00:00
linux32_sysvec.c Restore the segment registers and segment base MSRs for amd64 syscall 2009-07-09 09:34:11 +00:00
linux.h Implement accept4 syscall. 2009-06-01 20:48:39 +00:00
Makefile
syscalls.conf - Remove unused sysvec variables from various syscalls.conf. 2006-08-15 17:25:55 +00:00
syscalls.master Fix iovec32 for linux32/amd64. 2008-11-29 14:55:24 +00:00