The Unabridged Pentium 4 IA32 Processor Genealogy

Task Switch Details

Figure 11-3 on page 199 through Figure 11-5 on page 201 illustrate the steps taken by the processor to perform a switch from task to another.

Figure 11-3. Task Switch Flowchart (1-of-3)

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Figure 11-5. Task Switch Flowchart (3-of-3)

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Switch Due To an Interrupt or Exception

A task switch results when a hardware interrupt or a software exception selects an entry in the IDT (Interrupt Descriptor Table, pictured in Figure 11-2 on page 196) that contains a valid Task Gate. A privilege check ...