From 1d6bae966e90134bcfd7807b8f9488d55198de91 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Thu, 9 Aug 2012 19:16:14 -0400 Subject: tracing: Move raw output code from macro to standalone function The code for trace events to format the raw recorded event data into human readable format in the 'trace' file is repeated for every event in the system. When you have over 500 events, this can add up quite a bit. By making helper functions in the core kernel to do the work instead, we can shrink the size of the kernel down a bit. With a kernel configured with 502 events, the change in size was: text data bss dec hex filename 12991007 1913568 9785344 24689919 178bcff /tmp/vmlinux.orig 12990946 1913568 9785344 24689858 178bcc2 /tmp/vmlinux.patched Note, this version does not save as much as the version of this patch I had a few years ago. That is because in the mean time, commit f71130de5c7f ("tracing: Add a helper function for event print functions") did a lot of the work my original patch did. But this change helps slightly, and is part of a larger clean up to reduce the size much further. Link: http://lkml.kernel.org/r/20120810034707.378538034@goodmis.org Cc: Li Zefan Signed-off-by: Steven Rostedt --- kernel/trace/trace_output.c | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) (limited to 'kernel/trace/trace_output.c') diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c index ed32284fbe3..ca0e79e2aba 100644 --- a/kernel/trace/trace_output.c +++ b/kernel/trace/trace_output.c @@ -439,6 +439,37 @@ int ftrace_raw_output_prep(struct trace_iterator *iter, } EXPORT_SYMBOL(ftrace_raw_output_prep); +static int ftrace_output_raw(struct trace_iterator *iter, char *name, + char *fmt, va_list ap) +{ + struct trace_seq *s = &iter->seq; + int ret; + + ret = trace_seq_printf(s, "%s: ", name); + if (!ret) + return TRACE_TYPE_PARTIAL_LINE; + + ret = trace_seq_vprintf(s, fmt, ap); + + if (!ret) + return TRACE_TYPE_PARTIAL_LINE; + + return TRACE_TYPE_HANDLED; +} + +int ftrace_output_call(struct trace_iterator *iter, char *name, char *fmt, ...) +{ + va_list ap; + int ret; + + va_start(ap, fmt); + ret = ftrace_output_raw(iter, name, fmt, ap); + va_end(ap); + + return ret; +} +EXPORT_SYMBOL_GPL(ftrace_output_call); + #ifdef CONFIG_KRETPROBES static inline const char *kretprobed(const char *name) { -- cgit v1.2.3-70-g09d2 From 35bb4399bd0ef16b8a57fccea0047d98b6b0e7fb Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Thu, 9 Aug 2012 22:26:46 -0400 Subject: tracing: Move event storage for array from macro to standalone function The code that shows array fields for events is defined for all events. This can add up quite a bit when you have over 500 events. By making helper functions in the core kernel to do the work instead, we can shrink the size of the kernel down a bit. With a kernel configured with 502 events, the change in size was: text data bss dec hex filename 12990946 1913568 9785344 24689858 178bcc2 /tmp/vmlinux 12987390 1913504 9785344 24686238 178ae9e /tmp/vmlinux.patched That's a total of 3556 bytes, which comes down to 7 bytes per event. Although it's not much, this code is just called at initialization of the events. Link: http://lkml.kernel.org/r/20120810034708.084036335@goodmis.org Signed-off-by: Steven Rostedt --- include/linux/ftrace_event.h | 8 ++++---- include/trace/ftrace.h | 12 ++++-------- kernel/trace/trace_events.c | 6 ------ kernel/trace/trace_export.c | 12 ++++-------- kernel/trace/trace_output.c | 21 +++++++++++++++++++++ 5 files changed, 33 insertions(+), 26 deletions(-) (limited to 'kernel/trace/trace_output.c') diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h index a91ab93d725..ffe642eb84f 100644 --- a/include/linux/ftrace_event.h +++ b/include/linux/ftrace_event.h @@ -202,6 +202,10 @@ extern int ftrace_event_reg(struct ftrace_event_call *event, int ftrace_output_event(struct trace_iterator *iter, struct ftrace_event_call *event, char *fmt, ...); +int ftrace_event_define_field(struct ftrace_event_call *call, + char *type, int len, char *item, int offset, + int field_size, int sign, int filter); + enum { TRACE_EVENT_FL_FILTERED_BIT, TRACE_EVENT_FL_CAP_ANY_BIT, @@ -500,10 +504,6 @@ enum { FILTER_TRACE_FN, }; -#define EVENT_STORAGE_SIZE 128 -extern struct mutex event_storage_mutex; -extern char event_storage[EVENT_STORAGE_SIZE]; - extern int trace_event_raw_init(struct ftrace_event_call *call); extern int trace_define_field(struct ftrace_event_call *call, const char *type, const char *name, int offset, int size, diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h index 3873d6e4697..54928faf211 100644 --- a/include/trace/ftrace.h +++ b/include/trace/ftrace.h @@ -302,15 +302,11 @@ static struct trace_event_functions ftrace_event_type_funcs_##call = { \ #undef __array #define __array(type, item, len) \ do { \ - mutex_lock(&event_storage_mutex); \ BUILD_BUG_ON(len > MAX_FILTER_STR_VAL); \ - snprintf(event_storage, sizeof(event_storage), \ - "%s[%d]", #type, len); \ - ret = trace_define_field(event_call, event_storage, #item, \ - offsetof(typeof(field), item), \ - sizeof(field.item), \ - is_signed_type(type), FILTER_OTHER); \ - mutex_unlock(&event_storage_mutex); \ + ret = ftrace_event_define_field(event_call, #type, len, \ + #item, offsetof(typeof(field), item), \ + sizeof(field.item), \ + is_signed_type(type), FILTER_OTHER); \ if (ret) \ return ret; \ } while (0); diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index e71ffd4eccb..22826c73a9d 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -27,12 +27,6 @@ DEFINE_MUTEX(event_mutex); -DEFINE_MUTEX(event_storage_mutex); -EXPORT_SYMBOL_GPL(event_storage_mutex); - -char event_storage[EVENT_STORAGE_SIZE]; -EXPORT_SYMBOL_GPL(event_storage); - LIST_HEAD(ftrace_events); static LIST_HEAD(ftrace_common_fields); diff --git a/kernel/trace/trace_export.c b/kernel/trace/trace_export.c index 7c3e3e72e2b..39c746c5ae7 100644 --- a/kernel/trace/trace_export.c +++ b/kernel/trace/trace_export.c @@ -96,14 +96,10 @@ static void __always_unused ____ftrace_check_##name(void) \ #define __array(type, item, len) \ do { \ BUILD_BUG_ON(len > MAX_FILTER_STR_VAL); \ - mutex_lock(&event_storage_mutex); \ - snprintf(event_storage, sizeof(event_storage), \ - "%s[%d]", #type, len); \ - ret = trace_define_field(event_call, event_storage, #item, \ - offsetof(typeof(field), item), \ - sizeof(field.item), \ - is_signed_type(type), filter_type); \ - mutex_unlock(&event_storage_mutex); \ + ret = ftrace_event_define_field(event_call, #type, len, \ + #item, offsetof(typeof(field), item), \ + sizeof(field.item), \ + is_signed_type(type), filter_type); \ if (ret) \ return ret; \ } while (0); diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c index ca0e79e2aba..ee8d74840b8 100644 --- a/kernel/trace/trace_output.c +++ b/kernel/trace/trace_output.c @@ -20,6 +20,10 @@ static struct hlist_head event_hash[EVENT_HASHSIZE] __read_mostly; static int next_event_type = __TRACE_LAST_TYPE + 1; +#define EVENT_STORAGE_SIZE 128 +static DEFINE_MUTEX(event_storage_mutex); +static char event_storage[EVENT_STORAGE_SIZE]; + int trace_print_seq(struct seq_file *m, struct trace_seq *s) { int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len; @@ -470,6 +474,23 @@ int ftrace_output_call(struct trace_iterator *iter, char *name, char *fmt, ...) } EXPORT_SYMBOL_GPL(ftrace_output_call); +int ftrace_event_define_field(struct ftrace_event_call *call, + char *type, int len, char *item, int offset, + int field_size, int sign, int filter) +{ + int ret; + + mutex_lock(&event_storage_mutex); + snprintf(event_storage, sizeof(event_storage), + "%s[%d]", type, len); + ret = trace_define_field(call, event_storage, item, offset, + field_size, sign, filter); + mutex_unlock(&event_storage_mutex); + + return ret; +} +EXPORT_SYMBOL_GPL(ftrace_event_define_field); + #ifdef CONFIG_KRETPROBES static inline const char *kretprobed(const char *name) { -- cgit v1.2.3-70-g09d2 From bc4c426ee2431d1f717004d3bbaacbd819b544fd Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (Red Hat)" Date: Fri, 21 Mar 2014 08:23:38 -0400 Subject: Revert "tracing: Move event storage for array from macro to standalone function" I originally wrote commit 35bb4399bd0e to shrink the size of the overhead of tracepoints by several kilobytes. Later, I received a patch from Vaibhav Nagarnaik that fixed a bug in the same code that this commit touches. Not only did it fix a bug, it also removed code and shrunk the size of the overhead of trace events even more than this commit did. Since this commit is scheduled for 3.15 and Vaibhav's patch is already in mainline, I need to revert this patch in order to keep it from conflicting with Vaibhav's patch. Not to mention, Vaibhav's patch makes this patch obsolete. Link: http://lkml.kernel.org/r/20140320225637.0226041b@gandalf.local.home Cc: Vaibhav Nagarnaik Signed-off-by: Steven Rostedt --- include/linux/ftrace_event.h | 8 ++++++++ include/trace/ftrace.h | 12 ++++++++---- kernel/trace/trace_events.c | 6 ++++++ kernel/trace/trace_export.c | 12 ++++++++---- kernel/trace/trace_output.c | 21 --------------------- 5 files changed, 30 insertions(+), 29 deletions(-) (limited to 'kernel/trace/trace_output.c') diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h index 9d3fe065839..cdc975929d1 100644 --- a/include/linux/ftrace_event.h +++ b/include/linux/ftrace_event.h @@ -221,6 +221,10 @@ void *ftrace_event_buffer_reserve(struct ftrace_event_buffer *fbuffer, void ftrace_event_buffer_commit(struct ftrace_event_buffer *fbuffer); +int ftrace_event_define_field(struct ftrace_event_call *call, + char *type, int len, char *item, int offset, + int field_size, int sign, int filter); + enum { TRACE_EVENT_FL_FILTERED_BIT, TRACE_EVENT_FL_CAP_ANY_BIT, @@ -519,6 +523,10 @@ enum { FILTER_TRACE_FN, }; +#define EVENT_STORAGE_SIZE 128 +extern struct mutex event_storage_mutex; +extern char event_storage[EVENT_STORAGE_SIZE]; + extern int trace_event_raw_init(struct ftrace_event_call *call); extern int trace_define_field(struct ftrace_event_call *call, const char *type, const char *name, int offset, int size, diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h index e15ae4010d5..d1d91875faa 100644 --- a/include/trace/ftrace.h +++ b/include/trace/ftrace.h @@ -302,11 +302,15 @@ static struct trace_event_functions ftrace_event_type_funcs_##call = { \ #undef __array #define __array(type, item, len) \ do { \ + mutex_lock(&event_storage_mutex); \ BUILD_BUG_ON(len > MAX_FILTER_STR_VAL); \ - ret = ftrace_event_define_field(event_call, #type, len, \ - #item, offsetof(typeof(field), item), \ - sizeof(field.item), \ - is_signed_type(type), FILTER_OTHER); \ + snprintf(event_storage, sizeof(event_storage), \ + "%s[%d]", #type, len); \ + ret = trace_define_field(event_call, event_storage, #item, \ + offsetof(typeof(field), item), \ + sizeof(field.item), \ + is_signed_type(type), FILTER_OTHER); \ + mutex_unlock(&event_storage_mutex); \ if (ret) \ return ret; \ } while (0); diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index b8f73b333a3..2f7b8e31e3a 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -27,6 +27,12 @@ DEFINE_MUTEX(event_mutex); +DEFINE_MUTEX(event_storage_mutex); +EXPORT_SYMBOL_GPL(event_storage_mutex); + +char event_storage[EVENT_STORAGE_SIZE]; +EXPORT_SYMBOL_GPL(event_storage); + LIST_HEAD(ftrace_events); static LIST_HEAD(ftrace_common_fields); diff --git a/kernel/trace/trace_export.c b/kernel/trace/trace_export.c index 39c746c5ae7..7c3e3e72e2b 100644 --- a/kernel/trace/trace_export.c +++ b/kernel/trace/trace_export.c @@ -96,10 +96,14 @@ static void __always_unused ____ftrace_check_##name(void) \ #define __array(type, item, len) \ do { \ BUILD_BUG_ON(len > MAX_FILTER_STR_VAL); \ - ret = ftrace_event_define_field(event_call, #type, len, \ - #item, offsetof(typeof(field), item), \ - sizeof(field.item), \ - is_signed_type(type), filter_type); \ + mutex_lock(&event_storage_mutex); \ + snprintf(event_storage, sizeof(event_storage), \ + "%s[%d]", #type, len); \ + ret = trace_define_field(event_call, event_storage, #item, \ + offsetof(typeof(field), item), \ + sizeof(field.item), \ + is_signed_type(type), filter_type); \ + mutex_unlock(&event_storage_mutex); \ if (ret) \ return ret; \ } while (0); diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c index ee8d74840b8..ca0e79e2aba 100644 --- a/kernel/trace/trace_output.c +++ b/kernel/trace/trace_output.c @@ -20,10 +20,6 @@ static struct hlist_head event_hash[EVENT_HASHSIZE] __read_mostly; static int next_event_type = __TRACE_LAST_TYPE + 1; -#define EVENT_STORAGE_SIZE 128 -static DEFINE_MUTEX(event_storage_mutex); -static char event_storage[EVENT_STORAGE_SIZE]; - int trace_print_seq(struct seq_file *m, struct trace_seq *s) { int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len; @@ -474,23 +470,6 @@ int ftrace_output_call(struct trace_iterator *iter, char *name, char *fmt, ...) } EXPORT_SYMBOL_GPL(ftrace_output_call); -int ftrace_event_define_field(struct ftrace_event_call *call, - char *type, int len, char *item, int offset, - int field_size, int sign, int filter) -{ - int ret; - - mutex_lock(&event_storage_mutex); - snprintf(event_storage, sizeof(event_storage), - "%s[%d]", type, len); - ret = trace_define_field(call, event_storage, item, offset, - field_size, sign, filter); - mutex_unlock(&event_storage_mutex); - - return ret; -} -EXPORT_SYMBOL_GPL(ftrace_event_define_field); - #ifdef CONFIG_KRETPROBES static inline const char *kretprobed(const char *name) { -- cgit v1.2.3-70-g09d2 From de7b2973903c6cc50b31ee5682a69b2219b9919d Mon Sep 17 00:00:00 2001 From: Mathieu Desnoyers Date: Tue, 8 Apr 2014 17:26:21 -0400 Subject: tracepoint: Use struct pointer instead of name hash for reg/unreg tracepoints Register/unregister tracepoint probes with struct tracepoint pointer rather than tracepoint name. This change, which vastly simplifies tracepoint.c, has been proposed by Steven Rostedt. It also removes 8.8kB (mostly of text) to the vmlinux size. From this point on, the tracers need to pass a struct tracepoint pointer to probe register/unregister. A probe can now only be connected to a tracepoint that exists. Moreover, tracers are responsible for unregistering the probe before the module containing its associated tracepoint is unloaded. text data bss dec hex filename 10443444 4282528 10391552 25117524 17f4354 vmlinux.orig 10434930 4282848 10391552 25109330 17f2352 vmlinux Link: http://lkml.kernel.org/r/1396992381-23785-2-git-send-email-mathieu.desnoyers@efficios.com CC: Ingo Molnar CC: Frederic Weisbecker CC: Andrew Morton CC: Frank Ch. Eigler CC: Johannes Berg Signed-off-by: Mathieu Desnoyers [ SDR - fixed return val in void func in tracepoint_module_going() ] Signed-off-by: Steven Rostedt --- include/linux/ftrace_event.h | 22 +- include/linux/tracepoint.h | 41 +-- include/trace/ftrace.h | 9 +- kernel/trace/trace_events.c | 55 ++-- kernel/trace/trace_events_trigger.c | 2 +- kernel/trace/trace_kprobe.c | 21 +- kernel/trace/trace_output.c | 2 +- kernel/trace/trace_uprobe.c | 20 +- kernel/tracepoint.c | 511 ++++++++++++++++-------------------- 9 files changed, 331 insertions(+), 352 deletions(-) (limited to 'kernel/trace/trace_output.c') diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h index cdc30111d2f..d16da3e53bc 100644 --- a/include/linux/ftrace_event.h +++ b/include/linux/ftrace_event.h @@ -7,6 +7,7 @@ #include #include #include +#include struct trace_array; struct trace_buffer; @@ -232,6 +233,7 @@ enum { TRACE_EVENT_FL_IGNORE_ENABLE_BIT, TRACE_EVENT_FL_WAS_ENABLED_BIT, TRACE_EVENT_FL_USE_CALL_FILTER_BIT, + TRACE_EVENT_FL_TRACEPOINT_BIT, }; /* @@ -244,6 +246,7 @@ enum { * (used for module unloading, if a module event is enabled, * it is best to clear the buffers that used it). * USE_CALL_FILTER - For ftrace internal events, don't use file filter + * TRACEPOINT - Event is a tracepoint */ enum { TRACE_EVENT_FL_FILTERED = (1 << TRACE_EVENT_FL_FILTERED_BIT), @@ -252,12 +255,17 @@ enum { TRACE_EVENT_FL_IGNORE_ENABLE = (1 << TRACE_EVENT_FL_IGNORE_ENABLE_BIT), TRACE_EVENT_FL_WAS_ENABLED = (1 << TRACE_EVENT_FL_WAS_ENABLED_BIT), TRACE_EVENT_FL_USE_CALL_FILTER = (1 << TRACE_EVENT_FL_USE_CALL_FILTER_BIT), + TRACE_EVENT_FL_TRACEPOINT = (1 << TRACE_EVENT_FL_TRACEPOINT_BIT), }; struct ftrace_event_call { struct list_head list; struct ftrace_event_class *class; - char *name; + union { + char *name; + /* Set TRACE_EVENT_FL_TRACEPOINT flag when using "tp" */ + struct tracepoint *tp; + }; struct trace_event event; const char *print_fmt; struct event_filter *filter; @@ -271,6 +279,7 @@ struct ftrace_event_call { * bit 3: ftrace internal event (do not enable) * bit 4: Event was enabled by module * bit 5: use call filter rather than file filter + * bit 6: Event is a tracepoint */ int flags; /* static flags of different events */ @@ -283,6 +292,15 @@ struct ftrace_event_call { #endif }; +static inline const char * +ftrace_event_name(struct ftrace_event_call *call) +{ + if (call->flags & TRACE_EVENT_FL_TRACEPOINT) + return call->tp ? call->tp->name : NULL; + else + return call->name; +} + struct trace_array; struct ftrace_subsystem_dir; @@ -353,7 +371,7 @@ struct ftrace_event_file { #define __TRACE_EVENT_FLAGS(name, value) \ static int __init trace_init_flags_##name(void) \ { \ - event_##name.flags = value; \ + event_##name.flags |= value; \ return 0; \ } \ early_initcall(trace_init_flags_##name); diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h index 812b2553dfd..08150e26576 100644 --- a/include/linux/tracepoint.h +++ b/include/linux/tracepoint.h @@ -6,7 +6,7 @@ * * See Documentation/trace/tracepoints.txt. * - * (C) Copyright 2008 Mathieu Desnoyers + * Copyright (C) 2008-2014 Mathieu Desnoyers * * Heavily inspired from the Linux Kernel Markers. * @@ -21,6 +21,7 @@ struct module; struct tracepoint; +struct notifier_block; struct tracepoint_func { void *func; @@ -35,18 +36,13 @@ struct tracepoint { struct tracepoint_func __rcu *funcs; }; -/* - * Connect a probe to a tracepoint. - * Internal API, should not be used directly. - */ -extern int tracepoint_probe_register(const char *name, void *probe, void *data); - -/* - * Disconnect a probe from a tracepoint. - * Internal API, should not be used directly. - */ extern int -tracepoint_probe_unregister(const char *name, void *probe, void *data); +tracepoint_probe_register(struct tracepoint *tp, void *probe, void *data); +extern int +tracepoint_probe_unregister(struct tracepoint *tp, void *probe, void *data); +extern void +for_each_kernel_tracepoint(void (*fct)(struct tracepoint *tp, void *priv), + void *priv); #ifdef CONFIG_MODULES struct tp_module { @@ -54,12 +50,25 @@ struct tp_module { unsigned int num_tracepoints; struct tracepoint * const *tracepoints_ptrs; }; + bool trace_module_has_bad_taint(struct module *mod); +extern int register_tracepoint_module_notifier(struct notifier_block *nb); +extern int unregister_tracepoint_module_notifier(struct notifier_block *nb); #else static inline bool trace_module_has_bad_taint(struct module *mod) { return false; } +static inline +int register_tracepoint_module_notifier(struct notifier_block *nb) +{ + return 0; +} +static inline +int unregister_tracepoint_module_notifier(struct notifier_block *nb) +{ + return 0; +} #endif /* CONFIG_MODULES */ /* @@ -160,14 +169,14 @@ static inline void tracepoint_synchronize_unregister(void) static inline int \ register_trace_##name(void (*probe)(data_proto), void *data) \ { \ - return tracepoint_probe_register(#name, (void *)probe, \ - data); \ + return tracepoint_probe_register(&__tracepoint_##name, \ + (void *)probe, data); \ } \ static inline int \ unregister_trace_##name(void (*probe)(data_proto), void *data) \ { \ - return tracepoint_probe_unregister(#name, (void *)probe, \ - data); \ + return tracepoint_probe_unregister(&__tracepoint_##name,\ + (void *)probe, data); \ } \ static inline void \ check_trace_callback_type_##name(void (*cb)(data_proto)) \ diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h index 8765126b328..9c44c11cd9b 100644 --- a/include/trace/ftrace.h +++ b/include/trace/ftrace.h @@ -470,10 +470,11 @@ static inline notrace int ftrace_get_offsets_##call( \ * }; * * static struct ftrace_event_call event_ = { - * .name = "", + * .tp = &__tracepoint_, * .class = event_class_