diff --git a/Documentation/markers.txt b/Documentation/markers.txt deleted file mode 100644 index d2b3d0e91b26..000000000000 --- a/Documentation/markers.txt +++ /dev/null @@ -1,104 +0,0 @@ - Using the Linux Kernel Markers - - Mathieu Desnoyers - - -This document introduces Linux Kernel Markers and their use. It provides -examples of how to insert markers in the kernel and connect probe functions to -them and provides some examples of probe functions. - - -* Purpose of markers - -A marker placed in code provides a hook to call a function (probe) that you can -provide at runtime. A marker can be "on" (a probe is connected to it) or "off" -(no probe is attached). When a marker is "off" it has no effect, except for -adding a tiny time penalty (checking a condition for a branch) and space -penalty (adding a few bytes for the function call at the end of the -instrumented function and adds a data structure in a separate section). When a -marker is "on", the function you provide is called each time the marker is -executed, in the execution context of the caller. When the function provided -ends its execution, it returns to the caller (continuing from the marker site). - -You can put markers at important locations in the code. Markers are -lightweight hooks that can pass an arbitrary number of parameters, -described in a printk-like format string, to the attached probe function. - -They can be used for tracing and performance accounting. - - -* Usage - -In order to use the macro trace_mark, you should include linux/marker.h. - -#include - -And, - -trace_mark(subsystem_event, "myint %d mystring %s", someint, somestring); -Where : -- subsystem_event is an identifier unique to your event - - subsystem is the name of your subsystem. - - event is the name of the event to mark. -- "myint %d mystring %s" is the formatted string for the serializer. "myint" and - "mystring" are repectively the field names associated with the first and - second parameter. -- someint is an integer. -- somestring is a char pointer. - -Connecting a function (probe) to a marker is done by providing a probe (function -to call) for the specific marker through marker_probe_register() and can be -activated by calling marker_arm(). Marker deactivation can be done by calling -marker_disarm() as many times as marker_arm() has been called. Removing a probe -is done through marker_probe_unregister(); it will disarm the probe. - -marker_synchronize_unregister() must be called between probe unregistration and -the first occurrence of -- the end of module exit function, - to make sure there is no caller left using the probe; -- the free of any resource used by the probes, - to make sure the probes wont be accessing invalid data. -This, and the fact that preemption is disabled around the probe call, make sure -that probe removal and module unload are safe. See the "Probe example" section -below for a sample probe module. - -The marker mechanism supports inserting multiple instances of the same marker. -Markers can be put in inline functions, inlined static functions, and -unrolled loops as well as regular functions. - -The naming scheme "subsystem_event" is suggested here as a convention intended -to limit collisions. Marker names are global to the kernel: they are considered -as being the same whether they are in the core kernel image or in modules. -Conflicting format strings for markers with the same name will cause the markers -to be detected to have a different format string not to be armed and will output -a printk warning which identifies the inconsistency: - -"Format mismatch for probe probe_name (format), marker (format)" - -Another way to use markers is to simply define the marker without generating any -function call to actually call into the marker. This is useful in combination -with tracepoint probes in a scheme like this : - -void probe_tracepoint_name(unsigned int arg1, struct task_struct *tsk); - -DEFINE_MARKER_TP(marker_eventname, tracepoint_name, probe_tracepoint_name, - "arg1 %u pid %d"); - -notrace void probe_tracepoint_name(unsigned int arg1, struct task_struct *tsk) -{ - struct marker *marker = &GET_MARKER(kernel_irq_entry); - /* write data to trace buffers ... */ -} - -* Probe / marker example - -See the example provided in samples/markers/src - -Compile them with your kernel. - -Run, as root : -modprobe marker-example (insmod order is not important) -modprobe probe-example -cat /proc/marker-example (returns an expected error) -rmmod marker-example probe-example -dmesg diff --git a/arch/powerpc/platforms/cell/spufs/file.c b/arch/powerpc/platforms/cell/spufs/file.c index ab8aef9bb8ea..8f079b865ad0 100644 --- a/arch/powerpc/platforms/cell/spufs/file.c +++ b/arch/powerpc/platforms/cell/spufs/file.c @@ -29,7 +29,6 @@ #include #include #include -#include #include #include diff --git a/arch/powerpc/platforms/cell/spufs/sched.c b/arch/powerpc/platforms/cell/spufs/sched.c index bb5b77c66d05..4678078fede8 100644 --- a/arch/powerpc/platforms/cell/spufs/sched.c +++ b/arch/powerpc/platforms/cell/spufs/sched.c @@ -39,7 +39,6 @@ #include #include #include -#include #include #include diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h index bd099ba82ccc..4ec5e67e18cf 100644 --- a/include/linux/ftrace_event.h +++ b/include/linux/ftrace_event.h @@ -4,6 +4,7 @@ #include #include #include +#include struct trace_array; struct tracer; @@ -130,10 +131,15 @@ struct ftrace_event_call { void *data; atomic_t profile_count; - int (*profile_enable)(struct ftrace_event_call *); - void (*profile_disable)(struct ftrace_event_call *); + int (*profile_enable)(void); + void (*profile_disable)(void); }; +#define FTRACE_MAX_PROFILE_SIZE 2048 + +extern char *trace_profile_buf; +extern char *trace_profile_buf_nmi; + #define MAX_FILTER_PRED 32 #define MAX_FILTER_STR_VAL 256 /* Should handle KSYM_SYMBOL_LEN */ diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 4af56036a6bf..b7bbb5ddd7ae 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -15,7 +15,6 @@ #include #include #include -#include #include #include diff --git a/include/linux/marker.h b/include/linux/marker.h deleted file mode 100644 index b85e74ca782f..000000000000 --- a/include/linux/marker.h +++ /dev/null @@ -1,221 +0,0 @@ -#ifndef _LINUX_MARKER_H -#define _LINUX_MARKER_H - -/* - * Code markup for dynamic and static tracing. - * - * See Documentation/marker.txt. - * - * (C) Copyright 2006 Mathieu Desnoyers - * - * This file is released under the GPLv2. - * See the file COPYING for more details. - */ - -#include -#include - -struct module; -struct marker; - -/** - * marker_probe_func - Type of a marker probe function - * @probe_private: probe private data - * @call_private: call site private data - * @fmt: format string - * @args: variable argument list pointer. Use a pointer to overcome C's - * inability to pass this around as a pointer in a portable manner in - * the callee otherwise. - * - * Type of marker probe functions. They receive the mdata and need to parse the - * format string to recover the variable argument list. - */ -typedef void marker_probe_func(void *probe_private, void *call_private, - const char *fmt, va_list *args); - -struct marker_probe_closure { - marker_probe_func *func; /* Callback */ - void *probe_private; /* Private probe data */ -}; - -struct marker { - const char *name; /* Marker name */ - const char *format; /* Marker format string, describing the - * variable argument list. - */ - char state; /* Marker state. */ - char ptype; /* probe type : 0 : single, 1 : multi */ - /* Probe wrapper */ - void (*call)(const struct marker *mdata, void *call_private, ...); - struct marker_probe_closure single; - struct marker_probe_closure *multi; - const char *tp_name; /* Optional tracepoint name */ - void *tp_cb; /* Optional tracepoint callback */ -} __attribute__((aligned(8))); - -#ifdef CONFIG_MARKERS - -#define _DEFINE_MARKER(name, tp_name_str, tp_cb, format) \ - static const char __mstrtab_##name[] \ - __attribute__((section("__markers_strings"))) \ - = #name "\0" format; \ - static struct marker __mark_##name \ - __attribute__((section("__markers"), aligned(8))) = \ - { __mstrtab_##name, &__mstrtab_##name[sizeof(#name)], \ - 0, 0, marker_probe_cb, { __mark_empty_function, NULL},\ - NULL, tp_name_str, tp_cb } - -#define DEFINE_MARKER(name, format) \ - _DEFINE_MARKER(name, NULL, NULL, format) - -#define DEFINE_MARKER_TP(name, tp_name, tp_cb, format) \ - _DEFINE_MARKER(name, #tp_name, tp_cb, format) - -/* - * Note : the empty asm volatile with read constraint is used here instead of a - * "used" attribute to fix a gcc 4.1.x bug. - * Make sure the alignment of the structure in the __markers section will - * not add unwanted padding between the beginning of the section and the - * structure. Force alignment to the same alignment as the section start. - * - * The "generic" argument controls which marker enabling mechanism must be used. - * If generic is true, a variable read is used. - * If generic is false, immediate values are used. - */ -#define __trace_mark(generic, name, call_private, format, args...) \ - do { \ - DEFINE_MARKER(name, format); \ - __mark_check_format(format, ## args); \ - if (unlikely(__mark_##name.state)) { \ - (*__mark_##name.call) \ - (&__mark_##name, call_private, ## args);\ - } \ - } while (0) - -#define __trace_mark_tp(name, call_private, tp_name, tp_cb, format, args...) \ - do { \ - void __check_tp_type(void) \ - { \ - register_trace_##tp_name(tp_cb); \ - } \ - DEFINE_MARKER_TP(name, tp_name, tp_cb, format); \ - __mark_check_format(format, ## args); \ - (*__mark_##name.call)(&__mark_##name, call_private, \ - ## args); \ - } while (0) - -extern void marker_update_probe_range(struct marker *begin, - struct marker *end); - -#define GET_MARKER(name) (__mark_##name) - -#else /* !CONFIG_MARKERS */ -#define DEFINE_MARKER(name, tp_name, tp_cb, format) -#define __trace_mark(generic, name, call_private, format, args...) \ - __mark_check_format(format, ## args) -#define __trace_mark_tp(name, call_private, tp_name, tp_cb, format, args...) \ - do { \ - void __check_tp_type(void) \ - { \ - register_trace_##tp_name(tp_cb); \ - } \ - __mark_check_format(format, ## args); \ - } while (0) -static inline void marker_update_probe_range(struct marker *begin, - struct marker *end) -{ } -#define GET_MARKER(name) -#endif /* CONFIG_MARKERS */ - -/** - * trace_mark - Marker using code patching - * @name: marker name, not quoted. - * @format: format string - * @args...: variable argument list - * - * Places a marker using optimized code patching technique (imv_read()) - * to be enabled when immediate values are present. - */ -#define trace_mark(name, format, args...) \ - __trace_mark(0, name, NULL, format, ## args) - -/** - * _trace_mark - Marker using variable read - * @name: marker name, not quoted. - * @format: format string - * @args...: variable argument list - * - * Places a marker using a standard memory read (_imv_read()) to be - * enabled. Should be used for markers in code paths where instruction - * modification based enabling is not welcome. (__init and __exit functions, - * lockdep, some traps, printk). - */ -#define _trace_mark(name, format, args...) \ - __trace_mark(1, name, NULL, format, ## args) - -/** - * trace_mark_tp - Marker in a tracepoint callback - * @name: marker name, not quoted. - * @tp_name: tracepoint name, not quoted. - * @tp_cb: tracepoint callback. Should have an associated global symbol so it - * is not optimized away by the compiler (should not be static). - * @format: format string - * @args...: variable argument list - * - * Places a marker in a tracepoint callback. - */ -#define trace_mark_tp(name, tp_name, tp_cb, format, args...) \ - __trace_mark_tp(name, NULL, tp_name, tp_cb, format, ## args) - -/** - * MARK_NOARGS - Format string for a marker with no argument. - */ -#define MARK_NOARGS " " - -/* To be used for string format validity checking with gcc */ -static inline void __printf(1, 2) ___mark_check_format(const char *fmt, ...) -{ -} - -#define __mark_check_format(format, args...) \ - do { \ - if (0) \ - ___mark_check_format(format, ## args); \ - } while (0) - -extern marker_probe_func __mark_empty_function; - -extern void marker_probe_cb(const struct marker *mdata, - void *call_private, ...); - -/* - * Connect a probe to a marker. - * private data pointer must be a valid allocated memory address, or NULL. - */ -extern int marker_probe_register(const char *name, const char *format, - marker_probe_func *probe, void *probe_private); - -/* - * Returns the private data given to marker_probe_register. - */ -extern int marker_probe_unregister(const char *name, - marker_probe_func *probe, void *probe_private); -/* - * Unregister a marker by providing the registered private data. - */ -extern int marker_probe_unregister_private_data(marker_probe_func *probe, - void *probe_private); - -extern void *marker_get_private_data(const char *name, marker_probe_func *probe, - int num); - -/* - * marker_synchronize_unregister must be called between the last marker probe - * unregistration and the first one of - * - the end of module exit function - * - the free of any resource used by the probes - * to ensure the code and data are valid for any possibly running probes. - */ -#define marker_synchronize_unregister() synchronize_sched() - -#endif diff --git a/include/linux/module.h b/include/linux/module.h index f8f92d015efe..1c755b2f937d 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -15,7 +15,6 @@ #include #include #include -#include #include #include @@ -327,10 +326,6 @@ struct module /* The command line arguments (may be mangled). People like keeping pointers to this stuff */ char *args; -#ifdef CONFIG_MARKERS - struct marker *markers; - unsigned int num_markers; -#endif #ifdef CONFIG_TRACEPOINTS struct tracepoint *tracepoints; unsigned int num_tracepoints; @@ -535,8 +530,6 @@ int unregister_module_notifier(struct notifier_block * nb); extern void print_modules(void); -extern void module_update_markers(void); - extern void module_update_tracepoints(void); extern int module_get_iter_tracepoints(struct tracepoint_iter *iter); @@ -651,10 +644,6 @@ static inline void print_modules(void) { } -static inline void module_update_markers(void) -{ -} - static inline void module_update_tracepoints(void) { } diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index a8e37821cc60..7d9803cbb20f 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -100,33 +100,25 @@ struct perf_counter_attr; #ifdef CONFIG_EVENT_PROFILE #define TRACE_SYS_ENTER_PROFILE(sname) \ -static int prof_sysenter_enable_##sname(struct ftrace_event_call *event_call) \ +static int prof_sysenter_enable_##sname(void) \ { \ - int ret = 0; \ - if (!atomic_inc_return(&event_enter_##sname.profile_count)) \ - ret = reg_prof_syscall_enter("sys"#sname); \ - return ret; \ + return reg_prof_syscall_enter("sys"#sname); \ } \ \ -static void prof_sysenter_disable_##sname(struct ftrace_event_call *event_call)\ +static void prof_sysenter_disable_##sname(void) \ { \ - if (atomic_add_negative(-1, &event_enter_##sname.profile_count)) \ - unreg_prof_syscall_enter("sys"#sname); \ + unreg_prof_syscall_enter("sys"#sname); \ } #define TRACE_SYS_EXIT_PROFILE(sname) \ -static int prof_sysexit_enable_##sname(struct ftrace_event_call *event_call) \ +static int prof_sysexit_enable_##sname(void) \ { \ - int ret = 0; \ - if (!atomic_inc_return(&event_exit_##sname.profile_count)) \ - ret = reg_prof_syscall_exit("sys"#sname); \ - return ret; \ + return reg_prof_syscall_exit("sys"#sname); \ } \ \ -static void prof_sysexit_disable_##sname(struct ftrace_event_call *event_call) \ +static void prof_sysexit_disable_##sname(void) \ { \ - if (atomic_add_negative(-1, &event_exit_##sname.profile_count)) \ - unreg_prof_syscall_exit("sys"#sname); \ + unreg_prof_syscall_exit("sys"#sname); \ } #define TRACE_SYS_ENTER_PROFILE_INIT(sname) \ diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h index 72a3b437b829..a0361cb69769 100644 --- a/include/trace/ftrace.h +++ b/include/trace/ftrace.h @@ -382,20 +382,14 @@ static inline int ftrace_get_offsets_##call( \ * * NOTE: The insertion profile callback (ftrace_profile_) is defined later * - * static int ftrace_profile_enable_(struct ftrace_event_call *event_call) + * static int ftrace_profile_enable_(void) * { - * int ret = 0; - * - * if (!atomic_inc_return(&event_call->profile_count)) - * ret = register_trace_(ftrace_profile_); - * - * return ret; + * return register_trace_(ftrace_profile_); * } * - * static void ftrace_profile_disable_(struct ftrace_event_call *event_call) + * static void ftrace_profile_disable_(void) * { - * if (atomic_add_negative(-1, &event->call->profile_count)) - * unregister_trace_(ftrace_profile_); + * unregister_trace_(ftrace_profile_); * } * */ @@ -405,20 +399,14 @@ static inline int ftrace_get_offsets_##call( \ \ static void ftrace_profile_##call(proto); \ \ -static int ftrace_profile_enable_##call(struct ftrace_event_call *event_call) \ +static int ftrace_profile_enable_##call(void) \ { \ - int ret = 0; \ - \ - if (!atomic_inc_return(&event_call->profile_count)) \ - ret = register_trace_##call(ftrace_profile_##call); \ - \ - return ret; \ + return register_trace_##call(ftrace_profile_##call); \ } \ \ -static void ftrace_profile_disable_##call(struct ftrace_event_call *event_call)\ +static void ftrace_profile_disable_##call(void) \ { \ - if (atomic_add_negative(-1, &event_call->profile_count)) \ - unregister_trace_##call(ftrace_profile_##call); \ + unregister_trace_##call(ftrace_profile_##call); \ } #include TRACE_INCLUDE(TRACE_INCLUDE_FILE) @@ -660,11 +648,12 @@ __attribute__((section("_ftrace_events"))) event_##call = { \ * struct ftrace_raw_##call *entry; * u64 __addr = 0, __count = 1; * unsigned long irq_flags; + * struct trace_entry *ent; * int __entry_size; * int __data_size; + * int __cpu * int pc; * - * local_save_flags(irq_flags); * pc = preempt_count(); * * __data_size = ftrace_get_offsets_(&__data_offsets, args); @@ -675,25 +664,34 @@ __attribute__((section("_ftrace_events"))) event_##call = { \ * sizeof(u64)); * __entry_size -= sizeof(u32); * - * do { - * char raw_data[__entry_size]; <- allocate our sample in the stack - * struct trace_entry *ent; + * // Protect the non nmi buffer + * // This also protects the rcu read side + * local_irq_save(irq_flags); + * __cpu = smp_processor_id(); * - * zero dead bytes from alignment to avoid stack leak to userspace: + * if (in_nmi()) + * raw_data = rcu_dereference(trace_profile_buf_nmi); + * else + * raw_data = rcu_dereference(trace_profile_buf); * - * *(u64 *)(&raw_data[__entry_size - sizeof(u64)]) = 0ULL; - * entry = (struct ftrace_raw_ *)raw_data; - * ent = &entry->ent; - * tracing_generic_entry_update(ent, irq_flags, pc); - * ent->type = event_call->id; + * if (!raw_data) + * goto end; * - * <- do some jobs with dynamic arrays + * raw_data = per_cpu_ptr(raw_data, __cpu); * - * <- affect our values + * //zero dead bytes from alignment to avoid stack leak to userspace: + * *(u64 *)(&raw_data[__entry_size - sizeof(u64)]) = 0ULL; + * entry = (struct ftrace_raw_ *)raw_data; + * ent = &entry->ent; + * tracing_generic_entry_update(ent, irq_flags, pc); + * ent->type = event_call->id; * - * perf_tpcounter_event(event_call->id, __addr, __count, entry, - * __entry_size); <- submit them to perf counter - * } while (0); + * <- do some jobs with dynamic arrays + * + * <- affect our values + * + * perf_tpcounter_event(event_call->id, __addr, __count, entry, + * __entry_size); <- submit them to perf counter * * } */ @@ -716,11 +714,13 @@ static void ftrace_profile_##call(proto) \ struct ftrace_raw_##call *entry; \ u64 __addr = 0, __count = 1; \ unsigned long irq_flags; \ + struct trace_entry *ent; \ int __entry_size; \ int __data_size; \ + char *raw_data; \ + int __cpu; \ int pc; \ \ - local_save_flags(irq_flags); \ pc = preempt_count(); \ \ __data_size = ftrace_get_offsets_##call(&__data_offsets, args); \ @@ -728,23 +728,38 @@ static void ftrace_profile_##call(proto) \ sizeof(u64)); \ __entry_size -= sizeof(u32); \ \ - do { \ - char raw_data[__entry_size]; \ - struct trace_entry *ent; \ + if (WARN_ONCE(__entry_size > FTRACE_MAX_PROFILE_SIZE, \ + "profile buffer not large enough")) \ + return; \ \ - *(u64 *)(&raw_data[__entry_size - sizeof(u64)]) = 0ULL; \ - entry = (struct ftrace_raw_##call *)raw_data; \ - ent = &entry->ent; \ - tracing_generic_entry_update(ent, irq_flags, pc); \ - ent->type = event_call->id; \ + local_irq_save(irq_flags); \ + __cpu = smp_processor_id(); \ \ - tstruct \ + if (in_nmi()) \ + raw_data = rcu_dereference(trace_profile_buf_nmi); \ + else \ + raw_data = rcu_dereference(trace_profile_buf); \ \ - { assign; } \ + if (!raw_data) \ + goto end; \ \ - perf_tpcounter_event(event_call->id, __addr, __count, entry,\ + raw_data = per_cpu_ptr(raw_data, __cpu); \ + \ + *(u64 *)(&raw_data[__entry_size - sizeof(u64)]) = 0ULL; \ + entry = (struct ftrace_raw_##call *)raw_data; \ + ent = &entry->ent; \ + tracing_generic_entry_update(ent, irq_flags, pc); \ + ent->type = event_call->id; \ + \ + tstruct \ + \ + { assign; } \ + \ + perf_tpcounter_event(event_call->id, __addr, __count, entry, \ __entry_size); \ - } while (0); \ + \ +end: \ + local_irq_restore(irq_flags); \ \ } diff --git a/init/Kconfig b/init/Kconfig index 8e8b76d8a272..4cc0fa13d5eb 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -1054,13 +1054,6 @@ config PROFILING config TRACEPOINTS bool -config MARKERS - bool "Activate markers" - select TRACEPOINTS - help - Place an empty function call at each marker site. Can be - dynamically changed for a probe function. - source "arch/Kconfig" config SLOW_WORK diff --git a/kernel/Makefile b/kernel/Makefile index 3d9c7e27e3f9..7c9b0a585502 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -87,7 +87,6 @@ obj-$(CONFIG_RELAY) += relay.o obj-$(CONFIG_SYSCTL) += utsname_sysctl.o obj-$(CONFIG_TASK_DELAY_ACCT) += delayacct.o obj-$(CONFIG_TASKSTATS) += taskstats.o tsacct.o -obj-$(CONFIG_MARKERS) += marker.o obj-$(CONFIG_TRACEPOINTS) += tracepoint.o obj-$(CONFIG_LATENCYTOP) += latencytop.o obj-$(CONFIG_FUNCTION_TRACER) += trace/ diff --git a/kernel/marker.c b/kernel/marker.c deleted file mode 100644 index ea54f2647868..000000000000 --- a/kernel/marker.c +++ /dev/null @@ -1,930 +0,0 @@ -/* - * Copyright (C) 2007 Mathieu Desnoyers - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. - */ -#include -#include -#include -#include -#include -#include -#include -#include -#include - -extern struct marker __start___markers[]; -extern struct marker __stop___markers[]; - -/* Set to 1 to enable marker debug output */ -static const int marker_debug; - -/* - * markers_mutex nests inside module_mutex. Markers mutex protects the builtin - * and module markers and the hash table. - */ -static DEFINE_MUTEX(markers_mutex); - -/* - * Marker hash table, containing the active markers. - * Protected by module_mutex. - */ -#define MARKER_HASH_BITS 6 -#define MARKER_TABLE_SIZE (1 << MARKER_HASH_BITS) -static struct hlist_head marker_table[MARKER_TABLE_SIZE]; - -/* - * Note about RCU : - * It is used to make sure every handler has finished using its private data - * between two consecutive operation (add or remove) on a given marker. It is - * also used to delay the free of multiple probes array until a quiescent state - * is reached. - * marker entries modifications are protected by the markers_mutex. - */ -struct marker_entry { - struct hlist_node hlist; - char *format; - /* Probe wrapper */ - void (*call)(const struct marker *mdata, void *call_private, ...); - struct marker_probe_closure single; - struct marker_probe_closure *multi; - int refcount; /* Number of times armed. 0 if disarmed. */ - struct rcu_head rcu; - void *oldptr; - int rcu_pending; - unsigned char ptype:1; - unsigned char format_allocated:1; - char name[0]; /* Contains name'\0'format'\0' */ -}; - -/** - * __mark_empty_function - Empty probe callback - * @probe_private: probe private data - * @call_private: call site private data - * @fmt: format string - * @...: variable argument list - * - * Empty callback provided as a probe to the markers. By providing this to a - * disabled marker, we make sure the execution flow is always valid even - * though the function pointer change and the marker enabling are two distinct - * operations that modifies the execution flow of preemptible code. - */ -notrace void __mark_empty_function(void *probe_private, void *call_private, - const char *fmt, va_list *args) -{ -} -EXPORT_SYMBOL_GPL(__mark_empty_function); - -/* - * marker_probe_cb Callback that prepares the variable argument list for probes. - * @mdata: pointer of type struct marker - * @call_private: caller site private data - * @...: Variable argument list. - * - * Since we do not use "typical" pointer based RCU in the 1 argument case, we - * need to put a full smp_rmb() in this branch. This is why we do not use - * rcu_dereference() for the pointer read. - */ -notrace void marker_probe_cb(const struct marker *mdata, - void *call_private, ...) -{ - va_list args; - char ptype; - - /* - * rcu_read_lock_sched does two things : disabling preemption to make - * sure the teardown of the callbacks can be done correctly when they - * are in modules and they insure RCU read coherency. - */ - rcu_read_lock_sched_notrace(); - ptype = mdata->ptype; - if (likely(!ptype)) { - marker_probe_func *func; - /* Must read the ptype before ptr. They are not data dependant, - * so we put an explicit smp_rmb() here. */ - smp_rmb(); - func = mdata->single.func; - /* Must read the ptr before private data. They are not data - * dependant, so we put an explicit smp_rmb() here. */ - smp_rmb(); - va_start(args, call_private); - func(mdata->single.probe_private, call_private, mdata->format, - &args); - va_end(args); - } else { - struct marker_probe_closure *multi; - int i; - /* - * Read mdata->ptype before mdata->multi. - */ - smp_rmb(); - multi = mdata->multi; - /* - * multi points to an array, therefore accessing the array - * depends on reading multi. However, even in this case, - * we must insure that the pointer is read _before_ the array - * data. Same as rcu_dereference, but we need a full smp_rmb() - * in the fast path, so put the explicit barrier here. - */ - smp_read_barrier_depends(); - for (i = 0; multi[i].func; i++) { - va_start(args, call_private); - multi[i].func(multi[i].probe_private, call_private, - mdata->format, &args); - va_end(args); - } - } - rcu_read_unlock_sched_notrace(); -} -EXPORT_SYMBOL_GPL(marker_probe_cb); - -/* - * marker_probe_cb Callback that does not prepare the variable argument list. - * @mdata: pointer of type struct marker - * @call_private: caller site private data - * @...: Variable argument list. - * - * Should be connected to markers "MARK_NOARGS". - */ -static notrace void marker_probe_cb_noarg(const struct marker *mdata, - void *call_private, ...) -{ - va_list args; /* not initialized */ - char ptype; - - rcu_read_lock_sched_notrace(); - ptype = mdata->ptype; - if (likely(!ptype)) { - marker_probe_func *func; - /* Must read the ptype before ptr. They are not data dependant, - * so we put an explicit smp_rmb() here. */ - smp_rmb(); - func = mdata->single.func; - /* Must read the ptr before private data. They are not data - * dependant, so we put an explicit smp_rmb() here. */ - smp_rmb(); - func(mdata->single.probe_private, call_private, mdata->format, - &args); - } else { - struct marker_probe_closure *multi; - int i; - /* - * Read mdata->ptype before mdata->multi. - */ - smp_rmb(); - multi = mdata->multi; - /* - * multi points to an array, therefore accessing the array - * depends on reading multi. However, even in this case, - * we must insure that the pointer is read _before_ the array - * data. Same as rcu_dereference, but we need a full smp_rmb() - * in the fast path, so put the explicit barrier here. - */ - smp_read_barrier_depends(); - for (i = 0; multi[i].func; i++) - multi[i].func(multi[i].probe_private, call_private, - mdata->format, &args); - } - rcu_read_unlock_sched_notrace(); -} - -static void free_old_closure(struct rcu_head *head) -{ - struct marker_entry *entry = container_of(head, - struct marker_entry, rcu); - kfree(entry->oldptr); - /* Make sure we free the data before setting the pending flag to 0 */ - smp_wmb(); - entry->rcu_pending = 0; -} - -static void debug_print_probes(struct marker_entry *entry) -{ - int i; - - if (!marker_debug) - return; - - if (!entry->ptype) { - printk(KERN_DEBUG "Single probe : %p %p\n", - entry->single.func, - entry->single.probe_private); - } else { - for (i = 0; entry->multi[i].func; i++) - printk(KERN_DEBUG "Multi probe %d : %p %p\n", i, - entry->multi[i].func, - entry->multi[i].probe_private); - } -} - -static struct marker_probe_closure * -marker_entry_add_probe(struct marker_entry *entry, - marker_probe_func *probe, void *probe_private) -{ - int nr_probes = 0; - struct marker_probe_closure *old, *new; - - WARN_ON(!probe); - - debug_print_probes(entry); - old = entry->multi; - if (!entry->ptype) { - if (entry->single.func == probe && - entry->single.probe_private == probe_private) - return ERR_PTR(-EBUSY); - if (entry->single.func == __mark_empty_function) { - /* 0 -> 1 probes */ - entry->single.func = probe; - entry->single.probe_private = probe_private; - entry->refcount = 1; - entry->ptype = 0; - debug_print_probes(entry); - return NULL; - } else { - /* 1 -> 2 probes */ - nr_probes = 1; - old = NULL; - } - } else { - /* (N -> N+1), (N != 0, 1) probes */ - for (nr_probes = 0; old[nr_probes].func; nr_probes++) - if (old[nr_probes].func == probe - && old[nr_probes].probe_private - == probe_private) - return ERR_PTR(-EBUSY); - } - /* + 2 : one for new probe, one for NULL func */ - new = kzalloc((nr_probes + 2) * sizeof(struct marker_probe_closure), - GFP_KERNEL); - if (new == NULL) - return ERR_PTR(-ENOMEM); - if (!old) - new[0] = entry->single; - else - memcpy(new, old, - nr_probes * sizeof(struct marker_probe_closure)); - new[nr_probes].func = probe; - new[nr_probes].probe_private = probe_private; - entry->refcount = nr_probes + 1; - entry->multi = new; - entry->ptype = 1; - debug_print_probes(entry); - return old; -} - -static struct marker_probe_closure * -marker_entry_remove_probe(struct marker_entry *entry, - marker_probe_func *probe, void *probe_private) -{ - int nr_probes = 0, nr_del = 0, i; - struct marker_probe_closure *old, *new; - - old = entry->multi; - - debug_print_probes(entry); - if (!entry->ptype) { - /* 0 -> N is an error */ - WARN_ON(entry->single.func == __mark_empty_function); - /* 1 -> 0 probes */ - WARN_ON(probe && entry->single.func != probe); - WARN_ON(entry->single.probe_private != probe_private); - entry->single.func = __mark_empty_function; - entry->refcount = 0; - entry->ptype = 0; - debug_print_probes(entry); - return NULL; - } else { - /* (N -> M), (N > 1, M >= 0) probes */ - for (nr_probes = 0; old[nr_probes].func; nr_probes++) { - if ((!probe || old[nr_probes].func == probe) - && old[nr_probes].probe_private - == probe_private) - nr_del++; - } - } - - if (nr_probes - nr_del == 0) { - /* N -> 0, (N > 1) */ - entry->single.func = __mark_empty_function; - entry->refcount = 0; - entry->ptype = 0; - } else if (nr_probes - nr_del == 1) { - /* N -> 1, (N > 1) */ - for (i = 0; old[i].func; i++) - if ((probe && old[i].func != probe) || - old[i].probe_private != probe_private) - entry->single = old[i]; - entry->refcount = 1; - entry->ptype = 0; - } else { - int j = 0; - /* N -> M, (N > 1, M > 1) */ - /* + 1 for NULL */ - new = kzalloc((nr_probes - nr_del + 1) - * sizeof(struct marker_probe_closure), GFP_KERNEL); - if (new == NULL) - return ERR_PTR(-ENOMEM); - for (i = 0; old[i].func; i++) - if ((probe && old[i].func != probe) || - old[i].probe_private != probe_private) - new[j++] = old[i]; - entry->refcount = nr_probes - nr_del; - entry->ptype = 1; - entry->multi = new; - } - debug_print_probes(entry); - return old; -} - -/* - * Get marker if the marker is present in the marker hash table. - * Must be called with markers_mutex held. - * Returns NULL if not present. - */ -static struct marker_entry *get_marker(const char *name) -{ - struct hlist_head *head; - struct hlist_node *node; - struct marker_entry *e; - u32 hash = jhash(name, strlen(name), 0); - - head = &marker_table[hash & ((1 << MARKER_HASH_BITS)-1)]; - hlist_for_each_entry(e, node, head, hlist) { - if (!strcmp(name, e->name)) - return e; - } - return NULL; -} - -/* - * Add the marker to the marker hash table. Must be called with markers_mutex - * held. - */ -static struct marker_entry *add_marker(const char *name, const char *format) -{ - struct hlist_head *head; - struct hlist_node *node; - struct marker_entry *e; - size_t name_len = strlen(name) + 1; - size_t format_len = 0; - u32 hash = jhash(name, name_len-1, 0); - - if (format) - format_len = strlen(format) + 1; - head = &marker_table[hash & ((1 << MARKER_HASH_BITS)-1)]; - hlist_for_each_entry(e, node, head, hlist) { - if (!strcmp(name, e->name)) { - printk(KERN_NOTICE - "Marker %s busy\n", name); - return ERR_PTR(-EBUSY); /* Already there */ - } - } - /* - * Using kmalloc here to allocate a variable length element. Could - * cause some memory fragmentation if overused. - */ - e = kmalloc(sizeof(struct marker_entry) + name_len + format_len, - GFP_KERNEL); - if (!e) - return ERR_PTR(-ENOMEM); - memcpy(&e->name[0], name, name_len); - if (format) { - e->format = &e->name[name_len]; - memcpy(e->format, format, format_len); - if (strcmp(e->format, MARK_NOARGS) == 0) - e->call = marker_probe_cb_noarg; - else - e->call = marker_probe_cb; - trace_mark(core_marker_format, "name %s format %s", - e->name, e->format); - } else { - e->format = NULL; - e->call = marker_probe_cb; - } - e->single.func = __mark_empty_function; - e->single.probe_private = NULL; - e->multi = NULL; - e->ptype = 0; - e->format_allocated = 0; - e->refcount = 0; - e->rcu_pending = 0; - hlist_add_head(&e->hlist, head); - return e; -} - -/* - * Remove the marker from the marker hash table. Must be called with mutex_lock - * held. - */ -static int remove_marker(const char *name) -{ - struct hlist_head *head; - struct hlist_node *node; - struct marker_entry *e; - int found = 0; - size_t len = strlen(name) + 1; - u32 hash = jhash(name, len-1, 0); - - head = &marker_table[hash & ((1 << MARKER_HASH_BITS)-1)]; - hlist_for_each_entry(e, node, head, hlist) { - if (!strcmp(name, e->name)) { - found = 1; - break; - } - } - if (!found) - return -ENOENT; - if (e->single.func != __mark_empty_function) - return -EBUSY; - hlist_del(&e->hlist); - if (e->format_allocated) - kfree(e->format); - /* Make sure the call_rcu has been executed */ - if (e->rcu_pending) - rcu_barrier_sched(); - kfree(e); - return 0; -} - -/* - * Set the mark_entry format to the format found in the element. - */ -static int marker_set_format(struct marker_entry *entry, const char *format) -{ - entry->format = kstrdup(format, GFP_KERNEL); - if (!entry->format) - return -ENOMEM; - entry->format_allocated = 1; - - trace_mark(core_marker_format, "name %s format %s", - entry->name, entry->format); - return 0; -} - -/* - * Sets the probe callback corresponding to one marker. - */ -static int set_marker(struct marker_entry *entry, struct marker *elem, - int active) -{ - int ret = 0; - WARN_ON(strcmp(entry->name, elem->name) != 0); - - if (entry->format) { - if (strcmp(entry->format, elem->format) != 0) { - printk(KERN_NOTICE - "Format mismatch for probe %s " - "(%s), marker (%s)\n", - entry->name, - entry->format, - elem->format); - return -EPERM; - } - } else { - ret = marker_set_format(entry, elem->format); - if (ret) - return ret; - } - - /* - * probe_cb setup (statically known) is done here. It is - * asynchronous with the rest of execution, therefore we only - * pass from a "safe" callback (with argument) to an "unsafe" - * callback (does not set arguments). - */ - elem->call = entry->call; - /* - * Sanity check : - * We only update the single probe private data when the ptr is - * set to a _non_ single probe! (0 -> 1 and N -> 1, N != 1) - */ - WARN_ON(elem->single.func != __mark_empty_function - && elem->single.probe_private != entry->single.probe_private - && !elem->ptype); - elem->single.probe_private = entry->single.probe_private; - /* - * Make sure the private data is valid when we update the - * single probe ptr. - */ - smp_wmb(); - elem->single.func = entry->single.func; - /* - * We also make sure that the new probe callbacks array is consistent - * before setting a pointer to it. - */ - rcu_assign_pointer(elem->multi, entry->multi); - /* - * Update the function or multi probe array pointer before setting the - * ptype. - */ - smp_wmb(); - elem->ptype = entry->ptype; - - if (elem->tp_name && (active ^ elem->state)) { - WARN_ON(!elem->tp_cb); - /* - * It is ok to directly call the probe registration because type - * checking has been done in the __trace_mark_tp() macro. - */ - - if (active) { - /* - * try_module_get should always succeed because we hold - * lock_module() to get the tp_cb address. - */ - ret = try_module_get(__module_text_address( - (unsigned long)elem->tp_cb)); - BUG_ON(!ret); - ret = tracepoint_probe_register_noupdate( - elem->tp_name, - elem->tp_cb); - } else { - ret = tracepoint_probe_unregister_noupdate( - elem->tp_name, - elem->tp_cb); - /* - * tracepoint_probe_update_all() must be called - * before the module containing tp_cb is unloaded. - */ - module_put(__module_text_address( - (unsigned long)elem->tp_cb)); - } - } - elem->state = active; - - return ret; -} - -/* - * Disable a marker and its probe callback. - * Note: only waiting an RCU period after setting elem->call to the empty - * function insures that the original callback is not used anymore. This insured - * by rcu_read_lock_sched around the call site. - */ -static void disable_marker(struct marker *elem) -{ - int ret; - - /* leave "call" as is. It is known statically. */ - if (elem->tp_name && elem->state) { - WARN_ON(!elem->tp_cb); - /* - * It is ok to directly call the probe registration because type - * checking has been done in the __trace_mark_tp() macro. - */ - ret = tracepoint_probe_unregister_noupdate(elem->tp_name, - elem->tp_cb); - WARN_ON(ret); - /* - * tracepoint_probe_update_all() must be called - * before the module containing tp_cb is unloaded. - */ - module_put(__module_text_address((unsigned long)elem->tp_cb)); - } - elem->state = 0; - elem->single.func = __mark_empty_function; - /* Update the function before setting the ptype */ - smp_wmb(); - elem->ptype = 0; /* single probe */ - /* - * Leave the private data and id there, because removal is racy and - * should be done only after an RCU period. These are never used until - * the next initialization anyway. - */ -} - -/** - * marker_update_probe_range - Update a probe range - * @begin: beginning of the range - * @end: end of the range - * - * Updates the probe callback corresponding to a range of markers. - */ -void marker_update_probe_range(struct marker *begin, - struct marker *end) -{ - struct marker *iter; - struct marker_entry *mark_entry; - - mutex_lock(&markers_mutex); - for (iter = begin; iter < end; iter++) { - mark_entry = get_marker(iter->name); - if (mark_entry) { - set_marker(mark_entry, iter, !!mark_entry->refcount); - /* - * ignore error, continue - */ - } else { - disable_marker(iter); - } - } - mutex_unlock(&markers_mutex); -} - -/* - * Update probes, removing the faulty probes. - * - * Internal callback only changed before the first probe is connected to it. - * Single probe private data can only be changed on 0 -> 1 and 2 -> 1 - * transitions. All other transitions will leave the old private data valid. - * This makes the non-atomicity of the callback/private data updates valid. - * - * "special case" updates : - * 0 -> 1 callback - * 1 -> 0 callback - * 1 -> 2 callbacks - * 2 -> 1 callbacks - * Other updates all behave the same, just like the 2 -> 3 or 3 -> 2 updates. - * Site effect : marker_set_format may delete the marker entry (creating a - * replacement). - */ -static void marker_update_probes(void) -{ - /* Core kernel markers */ - marker_update_probe_range(__start___markers, __stop___markers); - /* Markers in modules. */ - module_update_markers(); - tracepoint_probe_update_all(); -} - -/** - * marker_probe_register - Connect a probe to a marker - * @name: marker name - * @format: format string - * @probe: probe handler - * @probe_private: probe private data - * - * private data must be a valid allocated memory address, or NULL. - * Returns 0 if ok, error value on error. - * The probe address must at least be aligned on the architecture pointer size. - */ -int marker_probe_register(const char *name, const char *format, - marker_probe_func *probe, void *probe_private) -{ - struct marker_entry *entry; - int ret = 0; - struct marker_probe_closure *old; - - mutex_lock(&markers_mutex); - entry = get_marker(name); - if (!entry) { - entry = add_marker(name, format); - if (IS_ERR(entry)) - ret = PTR_ERR(entry); - } else if (format) { - if (!entry->format) - ret = marker_set_format(entry, format); - else if (strcmp(entry->format, format)) - ret = -EPERM; - } - if (ret) - goto end; - - /* - * If we detect that a call_rcu is pending for this marker, - * make sure it's executed now. - */ - if (entry->rcu_pending) - rcu_barrier_sched(); - old = marker_entry_add_probe(entry, probe, probe_private); - if (IS_ERR(old)) { - ret = PTR_ERR(old); - goto end; - } - mutex_unlock(&markers_mutex); - marker_update_probes(); - mutex_lock(&markers_mutex); - entry = get_marker(name); - if (!entry) - goto end; - if (entry->rcu_pending) - rcu_barrier_sched(); - entry->oldptr = old; - entry->rcu_pending = 1; - /* write rcu_pending before calling the RCU callback */ - smp_wmb(); - call_rcu_sched(&entry->rcu, free_old_closure); -end: - mutex_unlock(&markers_mutex); - return ret; -} -EXPORT_SYMBOL_GPL(marker_probe_register); - -/** - * marker_probe_unregister - Disconnect a probe from a marker - * @name: marker name - * @probe: probe function pointer - * @probe_private: probe private data - * - * Returns the private data given to marker_probe_register, or an ERR_PTR(). - * We do not need to call a synchronize_sched to make sure the probes have - * finished running before doing a module unload, because the module unload - * itself uses stop_machine(), which insures that every preempt disabled section - * have finished. - */ -int marker_probe_unregister(const char *name, - marker_probe_func *probe, void *probe_private) -{ - struct marker_entry *entry; - struct marker_probe_closure *old; - int ret = -ENOENT; - - mutex_lock(&markers_mutex); - entry = get_marker(name); - if (!entry) - goto end; - if (entry->rcu_pending) - rcu_barrier_sched(); - old = marker_entry_remove_probe(entry, probe, probe_private); - mutex_unlock(&markers_mutex); - marker_update_probes(); - mutex_lock(&markers_mutex); - entry = get_marker(name); - if (!entry) - goto end; - if (entry->rcu_pending) - rcu_barrier_sched(); - entry->oldptr = old; - entry->rcu_pending = 1; - /* write rcu_pending before calling the RCU callback */ - smp_wmb(); - call_rcu_sched(&entry->rcu, free_old_closure); - remove_marker(name); /* Ignore busy error message */ - ret = 0; -end: - mutex_unlock(&markers_mutex); - return ret; -} -EXPORT_SYMBOL_GPL(marker_probe_unregister); - -static struct marker_entry * -get_marker_from_private_data(marker_probe_func *probe, void *probe_private) -{ - struct marker_entry *entry; - unsigned int i; - struct hlist_head *head; - struct hlist_node *node; - - for (i = 0; i < MARKER_TABLE_SIZE; i++) { - head = &marker_table[i]; - hlist_for_each_entry(entry, node, head, hlist) { - if (!entry->ptype) { - if (entry->single.func == probe - && entry->single.probe_private - == probe_private) - return entry; - } else { - struct marker_probe_closure *closure; - closure = entry->multi; - for (i = 0; closure[i].func; i++) { - if (closure[i].func == probe && - closure[i].probe_private - == probe_private) - return entry; - } - } - } - } - return NULL; -} - -/** - * marker_probe_unregister_private_data - Disconnect a probe from a marker - * @probe: probe function - * @probe_private: probe private data - * - * Unregister a probe by providing the registered private data. - * Only removes the first marker found in hash table. - * Return 0 on success or error value. - * We do not need to call a synchronize_sched to make sure the probes have - * finished running before doing a module unload, because the module unload - * itself uses stop_machine(), which insures that every preempt disabled section - * have finished. - */ -int marker_probe_unregister_private_data(marker_probe_func *probe, - void *probe_private) -{ - struct marker_entry *entry; - int ret = 0; - struct marker_probe_closure *old; - - mutex_lock(&markers_mutex); - entry = get_marker_from_private_data(probe, probe_private); - if (!entry) { - ret = -ENOENT; - goto end; - } - if (entry->rcu_pending) - rcu_barrier_sched(); - old = marker_entry_remove_probe(entry, NULL, probe_private); - mutex_unlock(&markers_mutex); - marker_update_probes(); - mutex_lock(&markers_mutex); - entry = get_marker_from_private_data(probe, probe_private); - if (!entry) - goto end; - if (entry->rcu_pending) - rcu_barrier_sched(); - entry->oldptr = old; - entry->rcu_pending = 1; - /* write rcu_pending before calling the RCU callback */ - smp_wmb(); - call_rcu_sched(&entry->rcu, free_old_closure); - remove_marker(entry->name); /* Ignore busy error message */ -end: - mutex_unlock(&markers_mutex); - return ret; -} -EXPORT_SYMBOL_GPL(marker_probe_unregister_private_data); - -/** - * marker_get_private_data - Get a marker's probe private data - * @name: marker name - * @probe: probe to match - * @num: get the nth matching probe's private data - * - * Returns the nth private data pointer (starting from 0) matching, or an - * ERR_PTR. - * Returns the private data pointer, or an ERR_PTR. - * The private data pointer should _only_ be dereferenced if the caller is the - * owner of the data, or its content could vanish. This is mostly used to - * confirm that a caller is the owner of a registered probe. - */ -void *marker_get_private_data(const char *name, marker_probe_func *probe, - int num) -{ - struct hlist_head *head; - struct hlist_node *node; - struct marker_entry *e; - size_t name_len = strlen(name) + 1; - u32 hash = jhash(name, name_len-1, 0); - int i; - - head = &marker_table[hash & ((1 << MARKER_HASH_BITS)-1)]; - hlist_for_each_entry(e, node, head, hlist) { - if (!strcmp(name, e->name)) { - if (!e->ptype) { - if (num == 0 && e->single.func == probe) - return e->single.probe_private; - } else { - struct marker_probe_closure *closure; - int match = 0; - closure = e->multi; - for (i = 0; closure[i].func; i++) { - if (closure[i].func != probe) - continue; - if (match++ == num) - return closure[i].probe_private; - } - } - break; - } - } - return ERR_PTR(-ENOENT); -} -EXPORT_SYMBOL_GPL(marker_get_private_data); - -#ifdef CONFIG_MODULES - -int marker_module_notify(struct notifier_block *self, - unsigned long val, void *data) -{ - struct module *mod = data; - - switch (val) { - case MODULE_STATE_COMING: - marker_update_probe_range(mod->markers, - mod->markers + mod->num_markers); - break; - case MODULE_STATE_GOING: - marker_update_probe_range(mod->markers, - mod->markers + mod->num_markers); - break; - } - return 0; -} - -struct notifier_block marker_module_nb = { - .notifier_call = marker_module_notify, - .priority = 0, -}; - -static int init_markers(void) -{ - return register_module_notifier(&marker_module_nb); -} -__initcall(init_markers); - -#endif /* CONFIG_MODULES */ diff --git a/kernel/module.c b/kernel/module.c index 05ce49ced8f6..b6ee424245dd 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -2237,10 +2237,6 @@ static noinline struct module *load_module(void __user *umod, sizeof(*mod->ctors), &mod->num_ctors); #endif -#ifdef CONFIG_MARKERS - mod->markers = section_objs(hdr, sechdrs, secstrings, "__markers", - sizeof(*mod->markers), &mod->num_markers); -#endif #ifdef CONFIG_TRACEPOINTS mod->tracepoints = section_objs(hdr, sechdrs, secstrings, "__tracepoints", @@ -2958,20 +2954,6 @@ void module_layout(struct module *mod, EXPORT_SYMBOL(module_layout); #endif -#ifdef CONFIG_MARKERS -void module_update_markers(void) -{ - struct module *mod; - - mutex_lock(&module_mutex); - list_for_each_entry(mod, &modules, list) - if (!mod->taints) - marker_update_probe_range(mod->markers, - mod->markers + mod->num_markers); - mutex_unlock(&module_mutex); -} -#endif - #ifdef CONFIG_TRACEPOINTS void module_update_tracepoints(void) { diff --git a/kernel/profile.c b/kernel/profile.c index 419250ebec4d..a55d3a367ae8 100644 --- a/kernel/profile.c +++ b/kernel/profile.c @@ -442,48 +442,51 @@ void profile_tick(int type) #ifdef CONFIG_PROC_FS #include +#include #include -static int prof_cpu_mask_read_proc(char *page, char **start, off_t off, - int count, int *eof, void *data) +static int prof_cpu_mask_proc_show(struct seq_file *m, void *v) { - int len = cpumask_scnprintf(page, count, data); - if (count - len < 2) - return -EINVAL; - len += sprintf(page + len, "\n"); - return len; + seq_cpumask(m, prof_cpu_mask); + seq_putc(m, '\n'); + return 0; } -static int prof_cpu_mask_write_proc(struct file *file, - const char __user *buffer, unsigned long count, void *data) +static int prof_cpu_mask_proc_open(struct inode *inode, struct file *file) +{ + return single_open(file, prof_cpu_mask_proc_show, NULL); +} + +static ssize_t prof_cpu_mask_proc_write(struct file *file, + const char __user *buffer, size_t count, loff_t *pos) { - struct cpumask *mask = data; - unsigned long full_count = count, err; cpumask_var_t new_value; + int err; if (!alloc_cpumask_var(&new_value, GFP_KERNEL)) return -ENOMEM; err = cpumask_parse_user(buffer, count, new_value); if (!err) { - cpumask_copy(mask, new_value); - err = full_count; + cpumask_copy(prof_cpu_mask, new_value); + err = count; } free_cpumask_var(new_value); return err; } +static const struct file_operations prof_cpu_mask_proc_fops = { + .open = prof_cpu_mask_proc_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, + .write = prof_cpu_mask_proc_write, +}; + void create_prof_cpu_mask(struct proc_dir_entry *root_irq_dir) { - struct proc_dir_entry *entry; - /* create /proc/irq/prof_cpu_mask */ - entry = create_proc_entry("prof_cpu_mask", 0600, root_irq_dir); - if (!entry) - return; - entry->data = prof_cpu_mask; - entry->read_proc = prof_cpu_mask_read_proc; - entry->write_proc = prof_cpu_mask_write_proc; + proc_create("prof_cpu_mask", 0600, root_irq_dir, &prof_cpu_mask_proc_fops); } /* diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index cc615f84751b..c71e91bf7372 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -2414,11 +2414,9 @@ unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS] __read_mostly; static void * __g_next(struct seq_file *m, loff_t *pos) { - unsigned long *array = m->private; - if (*pos >= ftrace_graph_count) return NULL; - return &array[*pos]; + return &ftrace_graph_funcs[*pos]; } static void * @@ -2482,17 +2480,11 @@ ftrace_graph_open(struct inode *inode, struct file *file) ftrace_graph_count = 0; memset(ftrace_graph_funcs, 0, sizeof(ftrace_graph_funcs)); } - - if (file->f_mode & FMODE_READ) { - ret = seq_open(file, &ftrace_graph_seq_ops); - if (!ret) { - struct seq_file *m = file->private_data; - m->private = ftrace_graph_funcs; - } - } else - file->private_data = ftrace_graph_funcs; mutex_unlock(&graph_lock); + if (file->f_mode & FMODE_READ) + ret = seq_open(file, &ftrace_graph_seq_ops); + return ret; } @@ -2560,7 +2552,6 @@ ftrace_graph_write(struct file *file, const char __user *ubuf, size_t cnt, loff_t *ppos) { struct trace_parser parser; - unsigned long *array; size_t read = 0; ssize_t ret; @@ -2574,12 +2565,6 @@ ftrace_graph_write(struct file *file, const char __user *ubuf, goto out; } - if (file->f_mode & FMODE_READ) { - struct seq_file *m = file->private_data; - array = m->private; - } else - array = file->private_data; - if (trace_parser_get_init(&parser, FTRACE_BUFF_MAX)) { ret = -ENOMEM; goto out; @@ -2591,7 +2576,7 @@ ftrace_graph_write(struct file *file, const char __user *ubuf, parser.buffer[parser.idx] = 0; /* we allow only one expression at a time */ - ret = ftrace_set_func(array, &ftrace_graph_count, + ret = ftrace_set_func(ftrace_graph_funcs, &ftrace_graph_count, parser.buffer); if (ret) goto out; diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index fd52a19dd172..861308072d28 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -125,13 +125,13 @@ int ftrace_dump_on_oops; static int tracing_set_tracer(const char *buf); -#define BOOTUP_TRACER_SIZE 100 -static char bootup_tracer_buf[BOOTUP_TRACER_SIZE] __initdata; +#define MAX_TRACER_SIZE 100 +static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata; static char *default_bootup_tracer; static int __init set_ftrace(char *str) { - strncpy(bootup_tracer_buf, str, BOOTUP_TRACER_SIZE); + strncpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); default_bootup_tracer = bootup_tracer_buf; /* We are using ftrace early, expand it */ ring_buffer_expanded = 1; @@ -241,13 +241,6 @@ static struct tracer *trace_types __read_mostly; /* current_trace points to the tracer that is currently active */ static struct tracer *current_trace __read_mostly; -/* - * max_tracer_type_len is used to simplify the allocating of - * buffers to read userspace tracer names. We keep track of - * the longest tracer name registered. - */ -static int max_tracer_type_len; - /* * trace_types_lock is used to protect the trace_types list. * This lock is also used to keep user access serialized. @@ -619,7 +612,6 @@ __releases(kernel_lock) __acquires(kernel_lock) { struct tracer *t; - int len; int ret = 0; if (!type->name) { @@ -627,6 +619,11 @@ __acquires(kernel_lock) return -1; } + if (strlen(type->name) > MAX_TRACER_SIZE) { + pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE); + return -1; + } + /* * When this gets called we hold the BKL which means that * preemption is disabled. Various trace selftests however @@ -641,7 +638,7 @@ __acquires(kernel_lock) for (t = trace_types; t; t = t->next) { if (strcmp(type->name, t->name) == 0) { /* already found */ - pr_info("Trace %s already registered\n", + pr_info("Tracer %s already registered\n", type->name); ret = -1; goto out; @@ -692,9 +689,6 @@ __acquires(kernel_lock) type->next = trace_types; trace_types = type; - len = strlen(type->name); - if (len > max_tracer_type_len) - max_tracer_type_len = len; out: tracing_selftest_running = false; @@ -703,7 +697,7 @@ __acquires(kernel_lock) if (ret || !default_bootup_tracer) goto out_unlock; - if (strncmp(default_bootup_tracer, type->name, BOOTUP_TRACER_SIZE)) + if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE)) goto out_unlock; printk(KERN_INFO "Starting tracer '%s'\n", type->name); @@ -725,14 +719,13 @@ __acquires(kernel_lock) void unregister_tracer(struct tracer *type) { struct tracer **t; - int len; mutex_lock(&trace_types_lock); for (t = &trace_types; *t; t = &(*t)->next) { if (*t == type) goto found; } - pr_info("Trace %s not registered\n", type->name); + pr_info("Tracer %s not registered\n", type->name); goto out; found: @@ -745,17 +738,7 @@ void unregister_tracer(struct tracer *type) current_trace->stop(&global_trace); current_trace = &nop_trace; } - - if (strlen(type->name) != max_tracer_type_len) - goto out; - - max_tracer_type_len = 0; - for (t = &trace_types; *t; t = &(*t)->next) { - len = strlen((*t)->name); - if (len > max_tracer_type_len) - max_tracer_type_len = len; - } - out: +out: mutex_unlock(&trace_types_lock); } @@ -2604,7 +2587,7 @@ static ssize_t tracing_set_trace_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) { - char buf[max_tracer_type_len+2]; + char buf[MAX_TRACER_SIZE+2]; int r; mutex_lock(&trace_types_lock); @@ -2754,15 +2737,15 @@ static ssize_t tracing_set_trace_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *ppos) { - char buf[max_tracer_type_len+1]; + char buf[MAX_TRACER_SIZE+1]; int i; size_t ret; int err; ret = cnt; - if (cnt > max_tracer_type_len) - cnt = max_tracer_type_len; + if (cnt > MAX_TRACER_SIZE) + cnt = MAX_TRACER_SIZE; if (copy_from_user(&buf, ubuf, cnt)) return -EFAULT; diff --git a/kernel/trace/trace_event_profile.c b/kernel/trace/trace_event_profile.c index 55a25c933d15..dd44b8768867 100644 --- a/kernel/trace/trace_event_profile.c +++ b/kernel/trace/trace_event_profile.c @@ -8,6 +8,57 @@ #include #include "trace.h" +/* + * We can't use a size but a type in alloc_percpu() + * So let's create a dummy type that matches the desired size + */ +typedef struct {char buf[FTRACE_MAX_PROFILE_SIZE];} profile_buf_t; + +char *trace_profile_buf; +EXPORT_SYMBOL_GPL(trace_profile_buf); + +char *trace_profile_buf_nmi; +EXPORT_SYMBOL_GPL(trace_profile_buf_nmi); + +/* Count the events in use (per event id, not per instance) */ +static int total_profile_count; + +static int ftrace_profile_enable_event(struct ftrace_event_call *event) +{ + char *buf; + int ret = -ENOMEM; + + if (atomic_inc_return(&event->profile_count)) + return 0; + + if (!total_profile_count++) { + buf = (char *)alloc_percpu(profile_buf_t); + if (!buf) + goto fail_buf; + + rcu_assign_pointer(trace_profile_buf, buf); + + buf = (char *)alloc_percpu(profile_buf_t); + if (!buf) + goto fail_buf_nmi; + + rcu_assign_pointer(trace_profile_buf_nmi, buf); + } + + ret = event->profile_enable(); + if (!ret) + return 0; + + kfree(trace_profile_buf_nmi); +fail_buf_nmi: + kfree(trace_profile_buf); +fail_buf: + total_profile_count--; + atomic_dec(&event->profile_count); + + return ret; +} + int ftrace_profile_enable(int event_id) { struct ftrace_event_call *event; @@ -17,7 +68,7 @@ int ftrace_profile_enable(int event_id) list_for_each_entry(event, &ftrace_events, list) { if (event->id == event_id && event->profile_enable && try_module_get(event->mod)) { - ret = event->profile_enable(event); + ret = ftrace_profile_enable_event(event); break; } } @@ -26,6 +77,33 @@ int ftrace_profile_enable(int event_id) return ret; } +static void ftrace_profile_disable_event(struct ftrace_event_call *event) +{ + char *buf, *nmi_buf; + + if (!atomic_add_negative(-1, &event->profile_count)) + return; + + event->profile_disable(); + + if (!--total_profile_count) { + buf = trace_profile_buf; + rcu_assign_pointer(trace_profile_buf, NULL); + + nmi_buf = trace_profile_buf_nmi; + rcu_assign_pointer(trace_profile_buf_nmi, NULL); + + /* + * Ensure every events in profiling have finished before + * releasing the buffers + */ + synchronize_sched(); + + free_percpu(buf); + free_percpu(nmi_buf); + } +} + void ftrace_profile_disable(int event_id) { struct ftrace_event_call *event; @@ -33,7 +111,7 @@ void ftrace_profile_disable(int event_id) mutex_lock(&event_mutex); list_for_each_entry(event, &ftrace_events, list) { if (event->id == event_id) { - event->profile_disable(event); + ftrace_profile_disable_event(event); module_put(event->mod); break; } diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index 56c260b83a9c..6f03c8a1105e 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -271,42 +271,32 @@ ftrace_event_write(struct file *file, const char __user *ubuf, static void * t_next(struct seq_file *m, void *v, loff_t *pos) { - struct list_head *list = m->private; - struct ftrace_event_call *call; + struct ftrace_event_call *call = v; (*pos)++; - for (;;) { - if (list == &ftrace_events) - return NULL; - - call = list_entry(list, struct ftrace_event_call, list); - + list_for_each_entry_continue(call, &ftrace_events, list) { /* * The ftrace subsystem is for showing formats only. * They can not be enabled or disabled via the event files. */ if (call->regfunc) - break; - - list = list->next; + return call; } - m->private = list->next; - - return call; + return NULL; } static void *t_start(struct seq_file *m, loff_t *pos) { - struct ftrace_event_call *call = NULL; + struct ftrace_event_call *call; loff_t l; mutex_lock(&event_mutex); - m->private = ftrace_events.next; + call = list_entry(&ftrace_events, struct ftrace_event_call, list); for (l = 0; l <= *pos; ) { - call = t_next(m, NULL, &l); + call = t_next(m, call, &l); if (!call) break; } @@ -316,37 +306,28 @@ static void *t_start(struct seq_file *m, loff_t *pos) static void * s_next(struct seq_file *m, void *v, loff_t *pos) { - struct list_head *list = m->private; - struct ftrace_event_call *call; + struct ftrace_event_call *call = v; (*pos)++; - retry: - if (list == &ftrace_events) - return NULL; - - call = list_entry(list, struct ftrace_event_call, list); - - if (!call->enabled) { - list = list->next; - goto retry; + list_for_each_entry_continue(call, &ftrace_events, list) { + if (call->enabled) + return call; } - m->private = list->next; - - return call; + return NULL; } static void *s_start(struct seq_file *m, loff_t *pos) { - struct ftrace_event_call *call = NULL; + struct ftrace_event_call *call; loff_t l; mutex_lock(&event_mutex); - m->private = ftrace_events.next; + call = list_entry(&ftrace_events, struct ftrace_event_call, list); for (l = 0; l <= *pos; ) { - call = s_next(m, NULL, &l); + call = s_next(m, call, &l); if (!call) break; } diff --git a/kernel/trace/trace_printk.c b/kernel/trace/trace_printk.c index 687699d365ae..2547d8813cf0 100644 --- a/kernel/trace/trace_printk.c +++ b/kernel/trace/trace_printk.c @@ -11,7 +11,6 @@ #include #include #include -#include #include #include #include diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c index 8712ce3c6a0e..7a3550cf2597 100644 --- a/kernel/trace/trace_syscalls.c +++ b/kernel/trace/trace_syscalls.c @@ -384,10 +384,13 @@ static int sys_prof_refcount_exit; static void prof_syscall_enter(struct pt_regs *regs, long id) { - struct syscall_trace_enter *rec; struct syscall_metadata *sys_data; + struct syscall_trace_enter *rec; + unsigned long flags; + char *raw_data; int syscall_nr; int size; + int cpu; syscall_nr = syscall_get_nr(current, regs); if (!test_bit(syscall_nr, enabled_prof_enter_syscalls)) @@ -402,20 +405,38 @@ static void prof_syscall_enter(struct pt_regs *regs, long id) size = ALIGN(size + sizeof(u32), sizeof(u64)); size -= sizeof(u32); - do { - char raw_data[size]; + if (WARN_ONCE(size > FTRACE_MAX_PROFILE_SIZE, + "profile buffer not large enough")) + return; - /* zero the dead bytes from align to not leak stack to user */ - *(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL; + /* Protect the per cpu buffer, begin the rcu read side */ + local_irq_save(flags); - rec = (struct syscall_trace_enter *) raw_data; - tracing_generic_entry_update(&rec->ent, 0, 0); - rec->ent.type = sys_data->enter_id; - rec->nr = syscall_nr; - syscall_get_arguments(current, regs, 0, sys_data->nb_args, - (unsigned long *)&rec->args); - perf_tpcounter_event(sys_data->enter_id, 0, 1, rec, size); - } while(0); + cpu = smp_processor_id(); + + if (in_nmi()) + raw_data = rcu_dereference(trace_profile_buf_nmi); + else + raw_data = rcu_dereference(trace_profile_buf); + + if (!raw_data) + goto end; + + raw_data = per_cpu_ptr(raw_data, cpu); + + /* zero the dead bytes from align to not leak stack to user */ + *(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL; + + rec = (struct syscall_trace_enter *) raw_data; + tracing_generic_entry_update(&rec->ent, 0, 0); + rec->ent.type = sys_data->enter_id; + rec->nr = syscall_nr; + syscall_get_arguments(current, regs, 0, sys_data->nb_args, + (unsigned long *)&rec->args); + perf_tpcounter_event(sys_data->enter_id, 0, 1, rec, size); + +end: + local_irq_restore(flags); } int reg_prof_syscall_enter(char *name) @@ -460,8 +481,12 @@ void unreg_prof_syscall_enter(char *name) static void prof_syscall_exit(struct pt_regs *regs, long ret) { struct syscall_metadata *sys_data; - struct syscall_trace_exit rec; + struct syscall_trace_exit *rec; + unsigned long flags; int syscall_nr; + char *raw_data; + int size; + int cpu; syscall_nr = syscall_get_nr(current, regs); if (!test_bit(syscall_nr, enabled_prof_exit_syscalls)) @@ -471,12 +496,46 @@ static void prof_syscall_exit(struct pt_regs *regs, long ret) if (!sys_data) return; - tracing_generic_entry_update(&rec.ent, 0, 0); - rec.ent.type = sys_data->exit_id; - rec.nr = syscall_nr; - rec.ret = syscall_get_return_value(current, regs); + /* We can probably do that at build time */ + size = ALIGN(sizeof(*rec) + sizeof(u32), sizeof(u64)); + size -= sizeof(u32); - perf_tpcounter_event(sys_data->exit_id, 0, 1, &rec, sizeof(rec)); + /* + * Impossible, but be paranoid with the future + * How to put this check outside runtime? + */ + if (WARN_ONCE(size > FTRACE_MAX_PROFILE_SIZE, + "exit event has grown above profile buffer size")) + return; + + /* Protect the per cpu buffer, begin the rcu read side */ + local_irq_save(flags); + cpu = smp_processor_id(); + + if (in_nmi()) + raw_data = rcu_dereference(trace_profile_buf_nmi); + else + raw_data = rcu_dereference(trace_profile_buf); + + if (!raw_data) + goto end; + + raw_data = per_cpu_ptr(raw_data, cpu); + + /* zero the dead bytes from align to not leak stack to user */ + *(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL; + + rec = (struct syscall_trace_exit *)raw_data; + + tracing_generic_entry_update(&rec->ent, 0, 0); + rec->ent.type = sys_data->exit_id; + rec->nr = syscall_nr; + rec->ret = syscall_get_return_value(current, regs); + + perf_tpcounter_event(sys_data->exit_id, 0, 1, rec, size); + +end: + local_irq_restore(flags); } int reg_prof_syscall_exit(char *name) diff --git a/samples/Kconfig b/samples/Kconfig index 428b065ba695..b92bde3c6a89 100644 --- a/samples/Kconfig +++ b/samples/Kconfig @@ -7,12 +7,6 @@ menuconfig SAMPLES if SAMPLES -config SAMPLE_MARKERS - tristate "Build markers examples -- loadable modules only" - depends on MARKERS && m - help - This build markers example modules. - config SAMPLE_TRACEPOINTS tristate "Build tracepoints examples -- loadable modules only" depends on TRACEPOINTS && m diff --git a/samples/Makefile b/samples/Makefile index 13e4b470b539..43343a03b1f4 100644 --- a/samples/Makefile +++ b/samples/Makefile @@ -1,3 +1,3 @@ # Makefile for Linux samples code -obj-$(CONFIG_SAMPLES) += markers/ kobject/ kprobes/ tracepoints/ trace_events/ +obj-$(CONFIG_SAMPLES) += kobject/ kprobes/ tracepoints/ trace_events/ diff --git a/samples/markers/Makefile b/samples/markers/Makefile deleted file mode 100644 index 6d7231265f0f..000000000000 --- a/samples/markers/Makefile +++ /dev/null @@ -1,4 +0,0 @@ -# builds the kprobes example kernel modules; -# then to use one (as root): insmod - -obj-$(CONFIG_SAMPLE_MARKERS) += probe-example.o marker-example.o diff --git a/samples/markers/marker-example.c b/samples/markers/marker-example.c deleted file mode 100644 index e9cd9c0bc84f..000000000000 --- a/samples/markers/marker-example.c +++ /dev/null @@ -1,53 +0,0 @@ -/* marker-example.c - * - * Executes a marker when /proc/marker-example is opened. - * - * (C) Copyright 2007 Mathieu Desnoyers - * - * This file is released under the GPLv2. - * See the file COPYING for more details. - */ - -#include -#include -#include -#include - -struct proc_dir_entry *pentry_example; - -static int my_open(struct inode *inode, struct file *file) -{ - int i; - - trace_mark(subsystem_event, "integer %d string %s", 123, - "example string"); - for (i = 0; i < 10; i++) - trace_mark(subsystem_eventb, MARK_NOARGS); - return -EPERM; -} - -static struct file_operations mark_ops = { - .open = my_open, -}; - -static int __init example_init(void) -{ - printk(KERN_ALERT "example init\n"); - pentry_example = proc_create("marker-example", 0444, NULL, &mark_ops); - if (!pentry_example) - return -EPERM; - return 0; -} - -static void __exit example_exit(void) -{ - printk(KERN_ALERT "example exit\n"); - remove_proc_entry("marker-example", NULL); -} - -module_init(example_init) -module_exit(example_exit) - -MODULE_LICENSE("GPL"); -MODULE_AUTHOR("Mathieu Desnoyers"); -MODULE_DESCRIPTION("Marker example"); diff --git a/samples/markers/probe-example.c b/samples/markers/probe-example.c deleted file mode 100644 index 2dfb3b32937e..000000000000 --- a/samples/markers/probe-example.c +++ /dev/null @@ -1,92 +0,0 @@ -/* probe-example.c - * - * Connects two functions to marker call sites. - * - * (C) Copyright 2007 Mathieu Desnoyers - * - * This file is released under the GPLv2. - * See the file COPYING for more details. - */ - -#include -#include -#include -#include -#include - -struct probe_data { - const char *name; - const char *format; - marker_probe_func *probe_func; -}; - -void probe_subsystem_event(void *probe_data, void *call_data, - const char *format, va_list *args) -{ - /* Declare args */ - unsigned int value; - const char *mystr; - - /* Assign args */ - value = va_arg(*args, typeof(value)); - mystr = va_arg(*args, typeof(mystr)); - - /* Call printk */ - printk(KERN_INFO "Value %u, string %s\n", value, mystr); - - /* or count, check rights, serialize data in a buffer */ -} - -atomic_t eventb_count = ATOMIC_INIT(0); - -void probe_subsystem_eventb(void *probe_data, void *call_data, - const char *format, va_list *args) -{ - /* Increment counter */ - atomic_inc(&eventb_count); -} - -static struct probe_data probe_array[] = -{ - { .name = "subsystem_event", - .format = "integer %d string %s", - .probe_func = probe_subsystem_event }, - { .name = "subsystem_eventb", - .format = MARK_NOARGS, - .probe_func = probe_subsystem_eventb }, -}; - -static int __init probe_init(void) -{ - int result; - int i; - - for (i = 0; i < ARRAY_SIZE(probe_array); i++) { - result = marker_probe_register(probe_array[i].name, - probe_array[i].format, - probe_array[i].probe_func, &probe_array[i]); - if (result) - printk(KERN_INFO "Unable to register probe %s\n", - probe_array[i].name); - } - return 0; -} - -static void __exit probe_fini(void) -{ - int i; - - for (i = 0; i < ARRAY_SIZE(probe_array); i++) - marker_probe_unregister(probe_array[i].name, - probe_array[i].probe_func, &probe_array[i]); - printk(KERN_INFO "Number of event b : %u\n", - atomic_read(&eventb_count)); - marker_synchronize_unregister(); -} - -module_init(probe_init); -module_exit(probe_fini); - -MODULE_LICENSE("GPL"); -MODULE_AUTHOR("Mathieu Desnoyers"); -MODULE_DESCRIPTION("SUBSYSTEM Probe"); diff --git a/scripts/Makefile.modpost b/scripts/Makefile.modpost index f4053dc7b5d6..8f14c81abbc7 100644 --- a/scripts/Makefile.modpost +++ b/scripts/Makefile.modpost @@ -13,7 +13,6 @@ # 2) modpost is then used to # 3) create one .mod.c file pr. module # 4) create one Module.symvers file with CRC for all exported symbols -# 4a) [CONFIG_MARKERS] create one Module.markers file listing defined markers # 5) compile all .mod.c files # 6) final link of the module to a file @@ -59,10 +58,6 @@ include scripts/Makefile.lib kernelsymfile := $(objtree)/Module.symvers modulesymfile := $(firstword $(KBUILD_EXTMOD))/Module.symvers -kernelmarkersfile := $(objtree)/Module.markers -modulemarkersfile := $(firstword $(KBUILD_EXTMOD))/Module.markers - -markersfile = $(if $(KBUILD_EXTMOD),$(modulemarkersfile),$(kernelmarkersfile)) # Step 1), find all modules listed in $(MODVERDIR)/ __modules := $(sort $(shell grep -h '\.ko' /dev/null $(wildcard $(MODVERDIR)/*.mod))) @@ -85,8 +80,6 @@ modpost = scripts/mod/modpost \ $(if $(KBUILD_EXTRA_SYMBOLS), $(patsubst %, -e %,$(KBUILD_EXTRA_SYMBOLS))) \ $(if $(KBUILD_EXTMOD),-o $(modulesymfile)) \ $(if $(CONFIG_DEBUG_SECTION_MISMATCH),,-S) \ - $(if $(CONFIG_MARKERS),-K $(kernelmarkersfile)) \ - $(if $(CONFIG_MARKERS),-M $(markersfile)) \ $(if $(KBUILD_EXTMOD)$(KBUILD_MODPOST_WARN),-w) \ $(if $(cross_build),-c) @@ -101,17 +94,12 @@ quiet_cmd_kernel-mod = MODPOST $@ cmd_kernel-mod = $(modpost) $@ vmlinux.o: FORCE - @rm -fr $(kernelmarkersfile) $(call cmd,kernel-mod) # Declare generated files as targets for modpost $(symverfile): __modpost ; $(modules:.ko=.mod.c): __modpost ; -ifdef CONFIG_MARKERS -$(markersfile): __modpost ; -endif - # Step 5), compile all *.mod.c files