We define a check function in order to avoid trouble with the include files. Then the higher level __this_cpu macros are modified to invoke the preemption check. Signed-off-by: Christoph Lameter Index: linux/include/linux/percpu.h =================================================================== --- linux.orig/include/linux/percpu.h 2013-12-02 16:07:52.314563523 -0600 +++ linux/include/linux/percpu.h 2013-12-02 16:09:08.000000000 -0600 @@ -175,6 +175,12 @@ extern phys_addr_t per_cpu_ptr_to_phys(v extern void __bad_size_call_parameter(void); +#ifdef CONFIG_DEBUG_PREEMPT +extern void __this_cpu_preempt_check(const char *op); +#else +static inline void __this_cpu_preempt_check(const char *op) { } +#endif + #define __pcpu_size_call_return(stem, variable) \ ({ typeof(variable) pscr_ret__; \ __verify_pcpu_ptr(&(variable)); \ @@ -727,18 +733,24 @@ do { \ /* * Generic percpu operations for context that are safe from preemption/interrupts. - * Checks will be added here soon. */ #ifndef __this_cpu_read -# define __this_cpu_read(pcp) __pcpu_size_call_return(raw_cpu_read_, (pcp)) +# define __this_cpu_read(pcp) \ + (__this_cpu_preempt_check("read"),__pcpu_size_call_return(raw_cpu_read_, (pcp))) #endif #ifndef __this_cpu_write -# define __this_cpu_write(pcp, val) __pcpu_size_call(raw_cpu_write_, (pcp), (val)) +# define __this_cpu_write(pcp, val) \ +do { __this_cpu_preempt_check("write"); \ + __pcpu_size_call(raw_cpu_write_, (pcp), (val)); \ +} while (0) #endif #ifndef __this_cpu_add -# define __this_cpu_add(pcp, val) __pcpu_size_call(raw_cpu_add_, (pcp), (val)) +# define __this_cpu_add(pcp, val) \ +do { __this_cpu_preempt_check("add"); \ + __pcpu_size_call(raw_cpu_add_, (pcp), (val)); \ +} while (0) #endif #ifndef __this_cpu_sub @@ -754,16 +766,23 @@ do { \ #endif #ifndef __this_cpu_and -# define __this_cpu_and(pcp, val) __pcpu_size_call(raw_cpu_and_, (pcp), (val)) +# define __this_cpu_and(pcp, val) \ +do { __this_cpu_preempt_check("and"); \ + __pcpu_size_call(raw_cpu_and_, (pcp), (val)); \ +} while (0) + #endif #ifndef __this_cpu_or -# define __this_cpu_or(pcp, val) __pcpu_size_call(raw_cpu_or_, (pcp), (val)) +# define __this_cpu_or(pcp, val) \ +do { __this_cpu_preempt_check("or"); \ + __pcpu_size_call(raw_cpu_or_, (pcp), (val)); \ +} while (0) #endif #ifndef __this_cpu_add_return # define __this_cpu_add_return(pcp, val) \ - __pcpu_size_call_return2(raw_cpu_add_return_, pcp, val) + (__this_cpu_preempt_check("add_return"),__pcpu_size_call_return2(raw_cpu_add_return_, pcp, val)) #endif #define __this_cpu_sub_return(pcp, val) __this_cpu_add_return(pcp, -(typeof(pcp))(val)) @@ -772,17 +791,17 @@ do { \ #ifndef __this_cpu_xchg # define __this_cpu_xchg(pcp, nval) \ - __pcpu_size_call_return2(raw_cpu_xchg_, (pcp), nval) + (__this_cpu_preempt_check("xchg"),__pcpu_size_call_return2(raw_cpu_xchg_, (pcp), nval)) #endif #ifndef __this_cpu_cmpxchg # define __this_cpu_cmpxchg(pcp, oval, nval) \ - __pcpu_size_call_return2(raw_cpu_cmpxchg_, pcp, oval, nval) + (__this_cpu_preempt_check("cmpxchg"),__pcpu_size_call_return2(raw_cpu_cmpxchg_, pcp, oval, nval)) #endif #ifndef __this_cpu_cmpxchg_double # define __this_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \ - __pcpu_double_call_return_bool(raw_cpu_cmpxchg_double_, (pcp1), (pcp2), (oval1), (oval2), (nval1), (nval2)) + (__this_cpu_preempt_check("cmpxchg_double"),__pcpu_double_call_return_bool(raw_cpu_cmpxchg_double_, (pcp1), (pcp2), (oval1), (oval2), (nval1), (nval2))) #endif #endif /* __LINUX_PERCPU_H */ Index: linux/lib/smp_processor_id.c =================================================================== --- linux.orig/lib/smp_processor_id.c 2013-12-02 16:07:52.314563523 -0600 +++ linux/lib/smp_processor_id.c 2013-12-02 16:07:52.314563523 -0600 @@ -7,7 +7,7 @@ #include #include -notrace unsigned int debug_smp_processor_id(void) +notrace static unsigned int check_preemption_disabled(char *what) { int this_cpu = raw_smp_processor_id(); @@ -38,9 +38,9 @@ notrace unsigned int debug_smp_processor if (!printk_ratelimit()) goto out_enable; - printk(KERN_ERR "BUG: using smp_processor_id() in preemptible [%08x] " - "code: %s/%d\n", - preempt_count() - 1, current->comm, current->pid); + printk(KERN_ERR "BUG: using %s in preemptible [%08x] code: %s/%d\n", + what, preempt_count() - 1, current->comm, current->pid); + print_symbol("caller is %s\n", (long)__builtin_return_address(0)); dump_stack(); @@ -50,5 +50,18 @@ out: return this_cpu; } +notrace unsigned int debug_smp_processor_id(void) +{ + return check_preemption_disabled("smp_processor_id()"); +} EXPORT_SYMBOL(debug_smp_processor_id); +notrace void __this_cpu_preempt_check(const char *op) +{ + char text[40]; + + snprintf(text, sizeof(text), "__this_cpu_%s()", op); + check_preemption_disabled(text); +} +EXPORT_SYMBOL(__this_cpu_preempt_check); + -- 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/