Messages in this thread | | | From | Brian Gerst <> | Date | Sun, 19 Jun 2016 18:05:54 -0400 | Subject | Re: [PATCH v2 0/6] x86: Rewrite switch_to() |
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On Sat, Jun 18, 2016 at 4:56 PM, Brian Gerst <brgerst@gmail.com> wrote: > This patch set simplifies the switch_to() code, by moving the stack switch > code out of line into an asm stub before calling __switch_to(). This ends > up being more readable, and using the C calling convention instead of > clobbering all registers improves code generation. It also allows newly > forked processes to construct a special stack frame to seamlessly flow > to ret_from_fork, instead of using a test and branch, or an unbalanced > call/ret. > > Changes from v1: > - Added struct inactive_task_frame > - Added comments about kernel threads returning to userspace > - Cleaned up some incorrect uses of thread.sp
I forgot to also add: - Rearranged inactive stack frame so that BP (frame pointer) is in the natural position right below the return address. This should take care of unwinding issues Josh raised.
-- Brian Gerst
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