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
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ia32_exception.S	Restore the segment registers and segment base MSRs for amd64 syscall	2009-07-09 09:34:11 +00:00
ia32_misc.c	Save and restore segment registers on amd64 when entering and leaving	2009-04-01 13:09:26 +00:00
ia32_reg.c	Restore the segment registers and segment base MSRs for amd64 syscall	2009-07-09 09:34:11 +00:00
ia32_signal.c	Restore the segment registers and segment base MSRs for amd64 syscall	2009-07-09 09:34:11 +00:00
ia32_sigtramp.S	Save and restore segment registers on amd64 when entering and leaving	2009-04-01 13:09:26 +00:00
ia32_syscall.c