On Mon, 11 Dec 2000 09:33:34 -0800,
"John Hawkes" <hawkes@xxxxxxxxxxxx> wrote:
>Is there a reason why the xfs version of arch/i386/kernel/semaphore.c
>has added:
> #if defined(CONFIG_FRAME_POINTER)
> ...
> #endif
>for the asm routines __down_failed, __down_failed_interruptible, and
>__down_failed_trylock, but *not* for __up_wakeup, __down_read_failed,
>and __down_write_failed?
That is from the kdb patch, not from XFS. Unfortunately the use of
CONFIG_FRAME_POINTER was added before I took over kdb so I am guessing
here. Early versions of kdb required frame pointers to do backtrace.
__down_failedxxx routines can wait so they often appear in back traces.
__up_wakeup never waits so it was probably ignored for back trace
purposes. __down_read_failed and __down_write_failed can wait, I have
no idea why they do not have frame pointers.
Current kdb does not need frame pointers to get a back trace on ix86 so
the lack of CONFIG_FRAME_POINTER on __up_wakeup, __down_read_failed and
__down_write_failed has not been a problem. For consistency, I will
add frame pointers to these routines in my next but one kdb patch.
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