From 1e8352784abaedb424e63fa700e93e6c1307785f Mon Sep 17 00:00:00 2001 From: Hugh Dickins <hugh@veritas.com> Date: Sat, 23 Feb 2008 19:40:17 +0000 Subject: [PATCH] percpu: fix DEBUG_PREEMPT per_cpu checking 2.6.25-rc1 percpu changes broke CONFIG_DEBUG_PREEMPT's per_cpu checking on several architectures. On s390, sparc64 and x86 it's been weakened to not checking at all; whereas on powerpc64 it's become too strict, issuing warnings from __raw_get_cpu_var in io_schedule and init_timer for example. Fix this by weakening powerpc's __my_cpu_offset to use the non-checking local_paca instead of get_paca (which itself contains such a check); and strengthening the generic my_cpu_offset to go the old slow way via smp_processor_id when CONFIG_DEBUG_PREEMPT (debug_smp_processor_id is where all the knowledge of what's correct when lives). Signed-off-by: Hugh Dickins <hugh@veritas.com> Reviewed-by: Mike Travis <travis@sgi.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> --- include/asm-generic/percpu.h | 2 ++ include/asm-powerpc/percpu.h | 2 +- 2 files changed, 3 insertions(+), 1 deletion(-) diff --git a/include/asm-generic/percpu.h b/include/asm-generic/percpu.h index 4b8d31cda1a0..b0e63c672ebd 100644 --- a/include/asm-generic/percpu.h +++ b/include/asm-generic/percpu.h @@ -32,6 +32,8 @@ extern unsigned long __per_cpu_offset[NR_CPUS]; */ #ifndef __my_cpu_offset #define __my_cpu_offset per_cpu_offset(raw_smp_processor_id()) +#endif +#ifdef CONFIG_DEBUG_PREEMPT #define my_cpu_offset per_cpu_offset(smp_processor_id()) #else #define my_cpu_offset __my_cpu_offset diff --git a/include/asm-powerpc/percpu.h b/include/asm-powerpc/percpu.h index ccb0523eb3b4..f879252b7ea6 100644 --- a/include/asm-powerpc/percpu.h +++ b/include/asm-powerpc/percpu.h @@ -13,7 +13,7 @@ #include <asm/paca.h> #define __per_cpu_offset(cpu) (paca[cpu].data_offset) -#define __my_cpu_offset get_paca()->data_offset +#define __my_cpu_offset local_paca->data_offset #define per_cpu_offset(x) (__per_cpu_offset(x)) #endif /* CONFIG_SMP */ -- 2.20.1