V3->V4: - Drop CONFIG_DEBUG_THIS_CPU_OPERATIONS - Add support for logging the exact operation that caused the issue. 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 check before __this_cpu operation Signed-off-by: Christoph Lameter Index: linux/include/linux/percpu.h =================================================================== --- linux.orig/include/linux/percpu.h 2013-10-10 11:30:17.111743444 -0500 +++ linux/include/linux/percpu.h 2013-10-10 10:30:26.817316787 -0500 @@ -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)); \ @@ -538,7 +544,8 @@ do { \ # ifndef __this_cpu_read_8 # define __this_cpu_read_8(pcp) (*__this_cpu_ptr(&(pcp))) # endif -# define __this_cpu_read(pcp) __pcpu_size_call_return(__this_cpu_read_, (pcp)) +# define __this_cpu_read(pcp) \ + (__this_cpu_preempt_check("read"),__pcpu_size_call_return(__this_cpu_read_, (pcp))) #endif #define __this_cpu_generic_to_op(pcp, val, op) \ @@ -559,7 +566,12 @@ do { \ # ifndef __this_cpu_write_8 # define __this_cpu_write_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), =) # endif -# define __this_cpu_write(pcp, val) __pcpu_size_call(__this_cpu_write_, (pcp), (val)) + +# define __this_cpu_write(pcp, val) \ +do { __this_cpu_preempt_check("write"); \ + __pcpu_size_call(__this_cpu_write_, (pcp), (val)); \ +} while (0) + #endif #ifndef __this_cpu_add @@ -575,7 +587,12 @@ do { \ # ifndef __this_cpu_add_8 # define __this_cpu_add_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), +=) # endif -# define __this_cpu_add(pcp, val) __pcpu_size_call(__this_cpu_add_, (pcp), (val)) + +# define __this_cpu_add(pcp, val) \ +do { __this_cpu_preempt_check("add"); \ + __pcpu_size_call(__this_cpu_add_, (pcp), (val)); \ +} while (0) + #endif #ifndef __this_cpu_sub @@ -603,7 +620,12 @@ do { \ # ifndef __this_cpu_and_8 # define __this_cpu_and_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), &=) # endif -# define __this_cpu_and(pcp, val) __pcpu_size_call(__this_cpu_and_, (pcp), (val)) + +# define __this_cpu_and(pcp, val) \ +do { __this_cpu_preempt_check("and"); \ + __pcpu_size_call(__this_cpu_and_, (pcp), (val)); \ +} while (0) + #endif #ifndef __this_cpu_or @@ -619,7 +641,12 @@ do { \ # ifndef __this_cpu_or_8 # define __this_cpu_or_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), |=) # endif -# define __this_cpu_or(pcp, val) __pcpu_size_call(__this_cpu_or_, (pcp), (val)) + +# define __this_cpu_or(pcp, val) \ +do { __this_cpu_preempt_check("or"); \ + __pcpu_size_call(__this_cpu_or_, (pcp), (val)); \ +} while (0) + #endif #ifndef __this_cpu_xor @@ -635,7 +662,12 @@ do { \ # ifndef __this_cpu_xor_8 # define __this_cpu_xor_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), ^=) # endif -# define __this_cpu_xor(pcp, val) __pcpu_size_call(__this_cpu_xor_, (pcp), (val)) + +# define __this_cpu_xor(pcp, val) \ +do { __this_cpu_preempt_check("xor"); \ + __pcpu_size_call(__this_cpu_xor_, (pcp), (val)); \ +} while (0) + #endif #define __this_cpu_generic_add_return(pcp, val) \ @@ -658,7 +690,7 @@ do { \ # define __this_cpu_add_return_8(pcp, val) __this_cpu_generic_add_return(pcp, val) # endif # define __this_cpu_add_return(pcp, val) \ - __pcpu_size_call_return2(__this_cpu_add_return_, pcp, val) + (__this_cpu_preempt_check("add_return"),__pcpu_size_call_return2(__this_cpu_add_return_, pcp, val)) #endif #define __this_cpu_sub_return(pcp, val) __this_cpu_add_return(pcp, -(val)) @@ -686,7 +718,7 @@ do { \ # define __this_cpu_xchg_8(pcp, nval) __this_cpu_generic_xchg(pcp, nval) # endif # define __this_cpu_xchg(pcp, nval) \ - __pcpu_size_call_return2(__this_cpu_xchg_, (pcp), nval) + (__this_cpu_preempt_check("xchg"),__pcpu_size_call_return2(__this_cpu_xchg_, (pcp), nval)) #endif #define __this_cpu_generic_cmpxchg(pcp, oval, nval) \ @@ -712,7 +744,7 @@ do { \ # define __this_cpu_cmpxchg_8(pcp, oval, nval) __this_cpu_generic_cmpxchg(pcp, oval, nval) # endif # define __this_cpu_cmpxchg(pcp, oval, nval) \ - __pcpu_size_call_return2(__this_cpu_cmpxchg_, pcp, oval, nval) + (__this_cpu_preempt_check("cmpxchg"),__pcpu_size_call_return2(__this_cpu_cmpxchg_, pcp, oval, nval)) #endif #define __this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \ @@ -745,7 +777,7 @@ do { \ __this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) # endif # define __this_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \ - __pcpu_double_call_return_bool(__this_cpu_cmpxchg_double_, (pcp1), (pcp2), (oval1), (oval2), (nval1), (nval2)) + (__this_cpu_preempt_check("cmpxchg_double"),__pcpu_double_call_return_bool(__this_cpu_cmpxchg_double_, (pcp1), (pcp2), (oval1), (oval2), (nval1), (nval2))) #endif /* Index: linux/lib/smp_processor_id.c =================================================================== --- linux.orig/lib/smp_processor_id.c 2013-10-10 11:30:17.111743444 -0500 +++ linux/lib/smp_processor_id.c 2013-10-10 10:32:16.046357108 -0500 @@ -7,7 +7,7 @@ #include #include -notrace unsigned int debug_smp_processor_id(void) +notrace static unsigned int check_preemption_disabled(char *what) { unsigned long preempt_count = preempt_count(); int this_cpu = raw_smp_processor_id(); @@ -39,9 +39,9 @@ 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 "%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(); @@ -51,5 +51,18 @@ out: return this_cpu; } +notrace unsigned int debug_smp_processor_id(void) +{ + return check_preemption_disabled("BUG: using 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 operation", 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/