FRV: Fix the section attribute on UP DECLARE_PER_CPU()

In non-SMP mode, the variable section attribute specified by DECLARE_PER_CPU()
does not agree with that specified by DEFINE_PER_CPU().  This means that
architectures that have a small data section references relative to a base
register may throw up linkage errors due to too great a displacement between
where the base register points and the per-CPU variable.

On FRV, the .h declaration says that the variable is in the .sdata section, but
the .c definition says it's actually in the .data section.  The linker throws
up the following errors:

kernel/built-in.o: In function `release_task':
kernel/exit.c:78: relocation truncated to fit: R_FRV_GPREL12 against symbol `per_cpu__process_counts' defined in .data section in kernel/built-in.o
kernel/exit.c:78: relocation truncated to fit: R_FRV_GPREL12 against symbol `per_cpu__process_counts' defined in .data section in kernel/built-in.o

To fix this, DECLARE_PER_CPU() should simply apply the same section attribute
as does DEFINE_PER_CPU().  However, this is made slightly more complex by
virtue of the fact that there are several variants on DEFINE, so these need to
be matched by variants on DECLARE.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/arch/alpha/include/asm/percpu.h b/arch/alpha/include/asm/percpu.h
index 3495e8e00d70fd2ca96531e702b1956a3aa5f5de..e9e0bb5a23bf5687096cbd5460b8d138ed5f5534 100644 (file)
--- a/arch/alpha/include/asm/percpu.h
+++ b/arch/alpha/include/asm/percpu.h
@@ -73,6 +73,6 @@ extern unsigned long __per_cpu_offset[NR_CPUS];
 
 #endif /* SMP */
 
-#define DECLARE_PER_CPU(type, name) extern __typeof__(type) per_cpu_var(name)
+#include <asm-generic/percpu.h>
 
 #endif /* __ALPHA_PERCPU_H */

diff --git a/arch/ia64/include/asm/smp.h b/arch/ia64/include/asm/smp.h
index 59840833625165fc72c75b40c24e94a1ba7db5ae..d217d1d4e05197351c6bc51c53bb946b3eae85ab 100644 (file)
--- a/arch/ia64/include/asm/smp.h
+++ b/arch/ia64/include/asm/smp.h
@@ -58,7 +58,7 @@ extern struct smp_boot_data {
 extern char no_int_routing __devinitdata;
 
 extern cpumask_t cpu_core_map[NR_CPUS];
-DECLARE_PER_CPU(cpumask_t, cpu_sibling_map);
+DECLARE_PER_CPU_SHARED_ALIGNED(cpumask_t, cpu_sibling_map);
 extern int smp_num_siblings;
 extern void __iomem *ipi_base_addr;
 extern unsigned char smp_int_redirect;

diff --git a/arch/x86/include/asm/desc.h b/arch/x86/include/asm/desc.h
index 5623c50d67b268a00c10dc60f8a5013f04bb28aa..c45f415ce315984c109ecbb0df763ae0e19866cd 100644 (file)
--- a/arch/x86/include/asm/desc.h
+++ b/arch/x86/include/asm/desc.h
@@ -37,7 +37,7 @@ extern gate_desc idt_table[];
 struct gdt_page {
        struct desc_struct gdt[GDT_ENTRIES];
 } __attribute__((aligned(PAGE_SIZE)));
-DECLARE_PER_CPU(struct gdt_page, gdt_page);
+DECLARE_PER_CPU_PAGE_ALIGNED(struct gdt_page, gdt_page);
 
 static inline struct desc_struct *get_cpu_gdt_table(unsigned int cpu)
 {

diff --git a/arch/x86/include/asm/hardirq.h b/arch/x86/include/asm/hardirq.h
index 039db6aa8e0271951706ee20bd9b819098f8002a..37555e52f980ac170e779dbe2aaa1e5e0c8ca07a 100644 (file)
--- a/arch/x86/include/asm/hardirq.h
+++ b/arch/x86/include/asm/hardirq.h
@@ -26,7 +26,7 @@ typedef struct {
 #endif
 } ____cacheline_aligned irq_cpustat_t;
 
-DECLARE_PER_CPU(irq_cpustat_t, irq_stat);
+DECLARE_PER_CPU_SHARED_ALIGNED(irq_cpustat_t, irq_stat);
 
 /* We can have at most NR_VECTORS irqs routed to a cpu at a time */
 #define MAX_HARDIRQS_PER_CPU NR_VECTORS

diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index fcf4d92e7e04d27c44393563528eda97cf4c5769..c2cceae709c8655338894c15b84c361e65caf727 100644 (file)
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -138,7 +138,7 @@ extern struct tss_struct    doublefault_tss;
 extern __u32                   cleared_cpu_caps[NCAPINTS];
 
 #ifdef CONFIG_SMP
-DECLARE_PER_CPU(struct cpuinfo_x86, cpu_info);
+DECLARE_PER_CPU_SHARED_ALIGNED(struct cpuinfo_x86, cpu_info);
 #define cpu_data(cpu)          per_cpu(cpu_info, cpu)
 #define current_cpu_data       __get_cpu_var(cpu_info)
 #else
@@ -270,7 +270,7 @@ struct tss_struct {
 
 } ____cacheline_aligned;
 
-DECLARE_PER_CPU(struct tss_struct, init_tss);
+DECLARE_PER_CPU_SHARED_ALIGNED(struct tss_struct, init_tss);
 
 /*
  * Save the original ist values for checking stack pointers during debugging
@@ -393,7 +393,7 @@ union irq_stack_union {
        };
 };
 
-DECLARE_PER_CPU(union irq_stack_union, irq_stack_union);
+DECLARE_PER_CPU_FIRST(union irq_stack_union, irq_stack_union);
 DECLARE_INIT_PER_CPU(irq_stack_union);
 
 DECLARE_PER_CPU(char *, irq_stack_ptr);

diff --git a/arch/x86/include/asm/tlbflush.h b/arch/x86/include/asm/tlbflush.h
index d3539f998f88c71dd6c9a784628c7d084d7521bc..16a5c84b032997f264f704ac68537dc65ba1dbe6 100644 (file)
--- a/arch/x86/include/asm/tlbflush.h
+++ b/arch/x86/include/asm/tlbflush.h
@@ -152,7 +152,7 @@ struct tlb_state {
        struct mm_struct *active_mm;
        int state;
 };
-DECLARE_PER_CPU(struct tlb_state, cpu_tlbstate);
+DECLARE_PER_CPU_SHARED_ALIGNED(struct tlb_state, cpu_tlbstate);
 
 static inline void reset_lazy_tlbstate(void)
 {

diff --git a/include/asm-generic/percpu.h b/include/asm-generic/percpu.h
index b0e63c672ebdf5a065ddea3374558a9638bc43c1..af47b9e1006432c82a8140dc52999fc055132128 100644 (file)
--- a/include/asm-generic/percpu.h
+++ b/include/asm-generic/percpu.h
@@ -73,11 +73,50 @@ extern void setup_per_cpu_areas(void);
 
 #endif /* SMP */
 
+#ifndef PER_CPU_BASE_SECTION
+#ifdef CONFIG_SMP
+#define PER_CPU_BASE_SECTION ".data.percpu"
+#else
+#define PER_CPU_BASE_SECTION ".data"
+#endif
+#endif
+
+#ifdef CONFIG_SMP
+
+#ifdef MODULE
+#define PER_CPU_SHARED_ALIGNED_SECTION ""
+#else
+#define PER_CPU_SHARED_ALIGNED_SECTION ".shared_aligned"
+#endif
+#define PER_CPU_FIRST_SECTION ".first"
+
+#else
+
+#define PER_CPU_SHARED_ALIGNED_SECTION ""
+#define PER_CPU_FIRST_SECTION ""
+
+#endif
+
 #ifndef PER_CPU_ATTRIBUTES
 #define PER_CPU_ATTRIBUTES
 #endif
 
-#define DECLARE_PER_CPU(type, name) extern PER_CPU_ATTRIBUTES \
-                                       __typeof__(type) per_cpu_var(name)
+#define DECLARE_PER_CPU_SECTION(type, name, section)                   \
+       extern \
+       __attribute__((__section__(PER_CPU_BASE_SECTION section)))      \
+       PER_CPU_ATTRIBUTES __typeof__(type) per_cpu__##name
+
+#define DECLARE_PER_CPU(type, name)                                    \
+       DECLARE_PER_CPU_SECTION(type, name, "")
+
+#define DECLARE_PER_CPU_SHARED_ALIGNED(type, name)                     \
+       DECLARE_PER_CPU_SECTION(type, name, PER_CPU_SHARED_ALIGNED_SECTION) \
+       ____cacheline_aligned_in_smp
+
+#define DECLARE_PER_CPU_PAGE_ALIGNED(type, name)                               \
+       DECLARE_PER_CPU_SECTION(type, name, ".page_aligned")
+
+#define DECLARE_PER_CPU_FIRST(type, name)                              \
+       DECLARE_PER_CPU_SECTION(type, name, PER_CPU_FIRST_SECTION)
 
 #endif /* _ASM_GENERIC_PERCPU_H_ */

diff --git a/include/linux/percpu.h b/include/linux/percpu.h
index cfda2d5ad319e75c8bf88b262d1b95bae8f3a2a6..f052d818499348ef24817335c44720454624b669 100644 (file)
--- a/include/linux/percpu.h
+++ b/include/linux/percpu.h
@@ -9,30 +9,6 @@
 
 #include <asm/percpu.h>
 
-#ifndef PER_CPU_BASE_SECTION
-#ifdef CONFIG_SMP
-#define PER_CPU_BASE_SECTION ".data.percpu"
-#else
-#define PER_CPU_BASE_SECTION ".data"
-#endif
-#endif
-
-#ifdef CONFIG_SMP
-
-#ifdef MODULE
-#define PER_CPU_SHARED_ALIGNED_SECTION ""
-#else
-#define PER_CPU_SHARED_ALIGNED_SECTION ".shared_aligned"
-#endif
-#define PER_CPU_FIRST_SECTION ".first"
-
-#else
-
-#define PER_CPU_SHARED_ALIGNED_SECTION ""
-#define PER_CPU_FIRST_SECTION ""
-
-#endif
-
 #define DEFINE_PER_CPU_SECTION(type, name, section)                    \
        __attribute__((__section__(PER_CPU_BASE_SECTION section)))      \
        PER_CPU_ATTRIBUTES __typeof__(type) per_cpu__##name

diff --git a/net/rds/rds.h b/net/rds/rds.h
index 619f0a30a4e566952642e27e1d2b49f5f546ad11..71794449ca4e58ffdbada8ac274a85b87418bf38 100644 (file)
--- a/net/rds/rds.h
+++ b/net/rds/rds.h
@@ -638,7 +638,7 @@ struct rds_message *rds_send_get_message(struct rds_connection *,
 void rds_rdma_unuse(struct rds_sock *rs, u32 r_key, int force);
 
 /* stats.c */
-DECLARE_PER_CPU(struct rds_statistics, rds_stats);
+DECLARE_PER_CPU_SHARED_ALIGNED(struct rds_statistics, rds_stats);
 #define rds_stats_inc_which(which, member) do {                \
        per_cpu(which, get_cpu()).member++;             \
        put_cpu();                                      \