From: Cliff Wickman <[email protected]>
Calling smp_processor_id() from within a preemptable region will issue
a warning if DEBUG_PREEMPT is set.
Which cpu is returned by smp_processor_id() is actually arbitrary here, as
every cpu has a per-cpu structure with the needed limit for the tunable. But
the call should be non-preemptable to avoid a warning in a DEBUG_PREEMPT
kernel.
Diffed against 3.0.0-rc3
Signed-off-by: Cliff Wickman <[email protected]>
---
arch/x86/platform/uv/tlb_uv.c | 2 ++
1 file changed, 2 insertions(+)
Index: linux/arch/x86/platform/uv/tlb_uv.c
===================================================================
--- linux.orig/arch/x86/platform/uv/tlb_uv.c
+++ linux/arch/x86/platform/uv/tlb_uv.c
@@ -1334,7 +1334,9 @@ static ssize_t tunables_write(struct fil
instr[count] = '\0';
+ preempt_disable(); /* avoid DEBUG_PREEMPT warning */
bcp = &per_cpu(bau_control, smp_processor_id());
+ preempt_enable_no_resched();
ret = parse_tunables_write(bcp, instr, count);
if (ret)