John Baldwin 0108cce0a4 Adjust the order of operations in spinlock_enter() and spinlock_exit() to ... work properly with single-stepping in a kernel debugger. Specifically, these routines have always disabled interrupts before increasing the nesting count and restored the prior state of interrupts after decreasing the nesting count to avoid problems with a nested interrupt not disabling interrupts when acquiring a spin lock. However, trap interrupts for single-stepping can still occur even when interrupts are disabled. Now the saved state of interrupts is not saved in the thread until after interrupts have been disabled and the nesting count has been increased. Similarly, the saved state from the thread cannot be read once the nesting count has been decreased to zero. To fix this, use temporary variables to store interrupt state and shuffle it between the thread's MD area and the appropriate registers. In cooperation with: bde MFC after: 1 month		2010-11-05 13:42:58 +00:00
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apm
cbus	Unify pc98 event timer code with the rest of x86.	2010-07-13 06:57:27 +00:00
compile
conf	Now userland POSIX semaphore is based on umtx. The kernel module	2010-09-24 09:04:16 +00:00
include	Move <machine/apicreg.h> to <x86/apicreg.h>.	2010-11-01 18:18:46 +00:00
linux
pc98	Adjust the order of operations in spinlock_enter() and spinlock_exit() to	2010-11-05 13:42:58 +00:00