Re: CVS commit: src/sys

[yamt%mwd.biglobe.ne.jp@localhost (YAMAMOTO Takashi)]

hi,

> Module Name:  src
> Committed By: dyoung
> Date:         Tue Nov  3 05:23:28 UTC 2009
> 
> Modified Files:
>       src/sys/arch/i386/conf: files.i386
>       src/sys/arch/i386/i386: spl.S
>       src/sys/arch/x86/x86: patch.c
>       src/sys/arch/xen/conf: files.xen
>       src/sys/kern: init_main.c kern_stub.c subr_prf.c
>       src/sys/sys: systm.h
> Added Files:
>       src/sys/kern: subr_spldebug.c
>       src/sys/sys: spldebug.h
> 
> Log Message:
> Add a kernel configuration flag, SPLDEBUG, that activates a per-CPU log
> of transitions to IPL_HIGH from lower IPLs.  SPLDEBUG is only available
> on i386 and Xen kernels, today.
> 
> 'options SPLDEBUG' adds instrumentation to spllower() and splraise() as
> well as routines to start/stop debugging and to record IPL transitions:
> spldebug_start(), spldebug_stop(), spldebug_raise(), spldebug_lower().

this seems too ad-hoc to me.

- please don't put MD code like this in kern/.  IPL_ values can't be
  compared with >= in MI code.  return_address.9 is in man.i386.
- there are other places where the spl value is modified.
  eg. interrupt stubs, lock stubs, etc.
- can you explain "cpu_index(ci) > MAXCPUS" and "cpu_index(ci) >= MAXCPUS" ?

YAMAMOTO Takashi

> 
> 
> To generate a diff of this commit:
> cvs rdiff -u -r1.351 -r1.352 src/sys/arch/i386/conf/files.i386
> cvs rdiff -u -r1.32 -r1.33 src/sys/arch/i386/i386/spl.S
> cvs rdiff -u -r1.18 -r1.19 src/sys/arch/x86/x86/patch.c
> cvs rdiff -u -r1.105 -r1.106 src/sys/arch/xen/conf/files.xen
> cvs rdiff -u -r1.407 -r1.408 src/sys/kern/init_main.c
> cvs rdiff -u -r1.20 -r1.21 src/sys/kern/kern_stub.c
> cvs rdiff -u -r1.136 -r1.137 src/sys/kern/subr_prf.c
> cvs rdiff -u -r0 -r1.1 src/sys/kern/subr_spldebug.c
> cvs rdiff -u -r0 -r1.1 src/sys/sys/spldebug.h
> cvs rdiff -u -r1.236 -r1.237 src/sys/sys/systm.h
> 
> Please note that diffs are not public domain; they are subject to the
> copyright notices on the relevant files.