Subject: + percpu-add-preemption-checks-to-__this_cpu-ops.patch added to -mm tree To: cl@xxxxxxxxx,mingo@xxxxxxxxxx,tj@xxxxxxxxxx From: akpm@xxxxxxxxxxxxxxxxxxxx Date: Tue, 04 Mar 2014 14:27:08 -0800 The patch titled Subject: percpu: add preemption checks to __this_cpu ops has been added to the -mm tree. Its filename is percpu-add-preemption-checks-to-__this_cpu-ops.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/percpu-add-preemption-checks-to-__this_cpu-ops.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/percpu-add-preemption-checks-to-__this_cpu-ops.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Christoph Lameter <cl@xxxxxxxxx> Subject: percpu: add preemption checks to __this_cpu ops 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 <cl@xxxxxxxxx> Acked-by: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Tejun Heo <tj@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/percpu.h | 39 +++++++++++++++++++++++++++++---------- lib/smp_processor_id.c | 20 ++++++++++++++++---- 2 files changed, 45 insertions(+), 14 deletions(-) diff -puN include/linux/percpu.h~percpu-add-preemption-checks-to-__this_cpu-ops include/linux/percpu.h --- a/include/linux/percpu.h~percpu-add-preemption-checks-to-__this_cpu-ops +++ a/include/linux/percpu.h @@ -173,6 +173,12 @@ 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)); \ @@ -725,18 +731,24 @@ 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 @@ -752,16 +764,23 @@ 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)) @@ -770,17 +789,17 @@ 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 */ diff -puN lib/smp_processor_id.c~percpu-add-preemption-checks-to-__this_cpu-ops lib/smp_processor_id.c --- a/lib/smp_processor_id.c~percpu-add-preemption-checks-to-__this_cpu-ops +++ a/lib/smp_processor_id.c @@ -7,7 +7,7 @@ #include <linux/kallsyms.h> #include <linux/sched.h> -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 +50,17 @@ 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); _ Patches currently in -mm which might be from cl@xxxxxxxxx are mm-close-pagetail-race.patch mm-page_alloc-make-first_page-visible-before-pagetail.patch kthread-ensure-locality-of-task_struct-allocations.patch mm-slab-slub-use-page-list-consistently-instead-of-page-lru.patch kobject-dont-block-for-each-kobject_uevent.patch kobject-dont-block-for-each-kobject_uevent-v2.patch slub-do-not-drop-slab_mutex-for-sysfs_slab_add.patch kmod-run-usermodehelpers-only-on-cpus-allowed-for-kthreadd-v2.patch kmod-run-usermodehelpers-only-on-cpus-allowed-for-kthreadd-v2-fix.patch kmod-run-usermodehelpers-only-on-cpus-allowed-for-kthreadd-v2-checkpatch-fixes.patch linux-next.patch percpu-add-raw_cpu_ops.patch mm-use-raw_cpu-ops-for-determining-current-numa-node.patch modules-use-raw_cpu_write-for-initialization-of-per-cpu-refcount.patch net-replace-__this_cpu_inc-in-routec-with-raw_cpu_inc.patch percpu-add-preemption-checks-to-__this_cpu-ops.patch mm-replace-__get_cpu_var-uses-with-this_cpu_ptr.patch tracing-replace-__get_cpu_var-uses-with-this_cpu_ptr.patch percpu-replace-__get_cpu_var-with-this_cpu_ptr.patch kernel-misc-replace-__get_cpu_var-uses.patch drivers-char-random-replace-__get_cpu_var-uses.patch drivers-cpuidle-replace-__get_cpu_var-uses-for-address-calculation.patch drivers-oprofile-replace-__get_cpu_var-uses-for-address-calculation.patch drivers-leds-replace-__get_cpu_var-use-through-this_cpu_ptr.patch drivers-clocksource-replace-__get_cpu_var-used-for-address-calculation.patch parisc-replace-__get_cpu_var-uses-for-address-calculation.patch metag-replace-__get_cpu_var-uses-for-address-calculation.patch drivers-net-ethernet-tile-replace-__get_cpu_var-uses-for-address-calculation.patch drivers-net-ethernet-tile-__get_cpu_var-call-introduced-in-314.patch tilegx-another-case-of-get_cpu_var.patch time-replace-__get_cpu_var-uses.patch scheduler-replace-__get_cpu_var-with-this_cpu_ptr.patch tick-sched-fix-two-new-uses-of-__get_cpu_ptr.patch block-replace-__this_cpu_ptr-with-raw_cpu_ptr.patch rcu-replace-__this_cpu_ptr-uses-with-raw_cpu_ptr.patch watchdog-replace-__raw_get_cpu_var-uses.patch net-replace-get_cpu_var-through-this_cpu_ptr.patch md-replace-__this_cpu_ptr-with-raw_cpu_ptr.patch irqchips-replace-__this_cpu_ptr-uses.patch x86-replace-__get_cpu_var-uses.patch x86-change-__get_cpu_var-calls-introduced-in-314.patch uv-replace-__get_cpu_var.patch arm-replace-__this_cpu_ptr-with-raw_cpu_ptr.patch mips-replace-__get_cpu_var-uses-in-fpu-emulator.patch mips-replace-__get_cpu_var-uses.patch s390-rename-__this_cpu_ptr-to-raw_cpu_ptr.patch s390-replace-__get_cpu_var-uses.patch s390-handle-new-__get_cpu_var-calls-added-in-314.patch ia64-replace-__get_cpu_var-uses.patch powerpc-replace-__get_cpu_var-uses.patch powerpc-handle-new-__get_cpu_var-calls-in-314.patch sparc-replace-__get_cpu_var-uses.patch tile-replace-__get_cpu_var-uses.patch blackfin-replace-__get_cpu_var-uses.patch avr32-replace-__get_cpu_var-with-__this_cpu_write.patch alpha-replace-__get_cpu_var.patch sh-replace-__get_cpu_var-uses.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html