Messages in this thread Patch in this message | | | Date | Wed, 25 Jul 2007 22:07:20 +1000 | From | Greg Ungerer <> | Subject | [M68KNOMMU]: simplify ColdFire resume code |
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It is useless to preserve THREAD_SR in `resume'. The real user's sr is actually in the stack. We also don't need to disable interrupts : we'll never be in an invalid state, the sp switch is atomic.
Signed-off-by: Philippe De Muyter <phdm@macqel.be> Signed-off-by: Greg Ungerer <gerg@uclinux.org> ---
diff -Naur linux-2.6.22/arch/m68knommu/platform/5307/entry.S linux-2.6.22-uc0/arch/m68knommu/platform/5307/entry.S --- linux-2.6.22/arch/m68knommu/platform/5307/entry.S 2007-07-12 15:23:02.000000000 +1000 +++ linux-2.6.22-uc0/arch/m68knommu/platform/5307/entry.S 2007-07-12 15:27:01.000000000 +1000 @@ -235,16 +216,12 @@ * Beware - when entering resume, prev (the current task) is * in a0, next (the new task) is in a1,so don't change these * registers until their contents are no longer needed. + * This is always called in supervisor mode, so don't bother to save + * and restore sr; user's process sr is actually in the stack. */ ENTRY(resume) movel %a0, %d1 /* get prev thread in d1 */ - movew %sr,%d0 /* save thread status reg */ - movew %d0,%a0@(TASK_THREAD+THREAD_SR) - - oril #0x700,%d0 /* disable interrupts */ - move %d0,%sr - movel sw_usp,%d0 /* save usp */ movel %d0,%a0@(TASK_THREAD+THREAD_USP) @@ -255,7 +232,4 @@ movel %a1@(TASK_THREAD+THREAD_USP),%a0 /* restore thread user stack */ movel %a0, sw_usp - - movew %a1@(TASK_THREAD+THREAD_SR),%d0 /* restore thread status reg */ - movew %d0, %sr rts - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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