From 2af15d6a44b871ad4c2a651302374cde8f335480 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Thu, 28 May 2009 13:37:24 -0400 Subject: [PATCH 01/10] ftrace: add kernel command line function filtering When using ftrace=function on the command line to trace functions on boot up, one can not filter out functions that are commonly called. This patch adds two new ftrace command line commands. ftrace_notrace=function-list ftrace_filter=function-list Where function-list is a comma separated list of functions to filter. The ftrace_notrace will make the functions listed not be included in the function tracing, and ftrace_filter will only trace the functions listed. These two act the same as the debugfs/tracing/set_ftrace_notrace and debugfs/tracing/set_ftrace_filter respectively. The simple glob expressions that are allowed by the filter files can also be used by the command line interface. ftrace_notrace=rcu*,*lock,*spin* Will not trace any function that starts with rcu, ends with lock, or has the word spin in it. Note, if the self tests are enabled, they may interfere with the filtering set by the command lines. Signed-off-by: Steven Rostedt --- Documentation/kernel-parameters.txt | 17 ++++++++++-- kernel/trace/ftrace.c | 42 +++++++++++++++++++++++++++++ 2 files changed, 57 insertions(+), 2 deletions(-) diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 9243dd84f4d6..fcd3bfbe74e8 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -751,12 +751,25 @@ and is between 256 and 4096 characters. It is defined in the file ia64_pal_cache_flush instead of SAL_CACHE_FLUSH. ftrace=[tracer] - [ftrace] will set and start the specified tracer + [FTRACE] will set and start the specified tracer as early as possible in order to facilitate early boot debugging. ftrace_dump_on_oops - [ftrace] will dump the trace buffers on oops. + [FTRACE] will dump the trace buffers on oops. + + ftrace_filter=[function-list] + [FTRACE] Limit the functions traced by the function + tracer at boot up. function-list is a comma separated + list of functions. This list can be changed at run + time by the set_ftrace_filter file in the debugfs + tracing directory. + + ftrace_notrace=[function-list] + [FTRACE] Do not trace the functions specified in + function-list. This list can be changed at run time + by the set_ftrace_notrace file in the debugfs + tracing directory. gamecon.map[2|3]= [HW,JOY] Multisystem joystick and NES/SNES/PSX pad diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 140699a9a8a7..2074e5b7766b 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -32,6 +32,7 @@ #include #include +#include #include "trace_output.h" #include "trace_stat.h" @@ -2369,6 +2370,45 @@ void ftrace_set_notrace(unsigned char *buf, int len, int reset) ftrace_set_regex(buf, len, reset, 0); } +/* + * command line interface to allow users to set filters on boot up. + */ +#define FTRACE_FILTER_SIZE COMMAND_LINE_SIZE +static char ftrace_notrace_buf[FTRACE_FILTER_SIZE] __initdata; +static char ftrace_filter_buf[FTRACE_FILTER_SIZE] __initdata; + +static int __init set_ftrace_notrace(char *str) +{ + strncpy(ftrace_notrace_buf, str, FTRACE_FILTER_SIZE); + return 1; +} +__setup("ftrace_notrace=", set_ftrace_notrace); + +static int __init set_ftrace_filter(char *str) +{ + strncpy(ftrace_filter_buf, str, FTRACE_FILTER_SIZE); + return 1; +} +__setup("ftrace_filter=", set_ftrace_filter); + +static void __init set_ftrace_early_filter(char *buf, int enable) +{ + char *func; + + while (buf) { + func = strsep(&buf, ","); + ftrace_set_regex(func, strlen(func), 0, enable); + } +} + +static void __init set_ftrace_early_filters(void) +{ + if (ftrace_filter_buf[0]) + set_ftrace_early_filter(ftrace_filter_buf, 1); + if (ftrace_notrace_buf[0]) + set_ftrace_early_filter(ftrace_notrace_buf, 0); +} + static int ftrace_regex_release(struct inode *inode, struct file *file, int enable) { @@ -2829,6 +2869,8 @@ void __init ftrace_init(void) if (ret) pr_warning("Failed to register trace ftrace module notifier\n"); + set_ftrace_early_filters(); + return; failed: ftrace_disabled = 1; From 5e0a093910876882f91f1d4b8a1635a099e6c7ba Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Thu, 28 May 2009 15:50:13 -0400 Subject: [PATCH 02/10] tracing: fix config options to not show when automatically selected There are two options that are selected by all tracers, but we want to have those options available when no tracer is selected. These are The event tracer and sched switch tracer. The are enabled by all tracers, but if a tracer is not selected we want the options to appear. All tracers including them select TRACING. Thus what we would like to do is: config EVENT_TRACER bool "prompt" depends on TRACING select TRACING But that gives us a bug in the kbuild system since we just created a circular dependency. We only want the prompt to show when TRACING is off. This patch adds GENERIC_TRACER that all tracers will select instead of TRACING. The two options (sched switch and event tracer) will select TRACING directly and depend on !GENERIC_TRACER. This solves the cicular dependency. [ Impact: hide options that are selected by default ] Signed-off-by: Steven Rostedt --- kernel/trace/Kconfig | 43 ++++++++++++++++++++++++++++--------------- 1 file changed, 28 insertions(+), 15 deletions(-) diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index a508b9d2adb8..6e55cc3ac49d 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -56,6 +56,13 @@ config CONTEXT_SWITCH_TRACER select MARKERS bool +# All tracer options should select GENERIC_TRACER. For those options that are +# enabled by all tracers (context switch and event tracer) they select TRACING. +# This allows those options to appear when no other tracer is selected. But the +# options do not appear when something else selects it. We need the two options +# GENERIC_TRACER and TRACING to avoid circular dependencies to accomplish the +# hidding of the automatic options options. + config TRACING bool select DEBUG_FS @@ -66,6 +73,10 @@ config TRACING select BINARY_PRINTF select EVENT_TRACING +config GENERIC_TRACER + bool + select TRACING + # # Minimum requirements an architecture has to meet for us to # be able to offer generic tracing facilities: @@ -95,7 +106,7 @@ config FUNCTION_TRACER depends on HAVE_FUNCTION_TRACER select FRAME_POINTER select KALLSYMS - select TRACING + select GENERIC_TRACER select CONTEXT_SWITCH_TRACER help Enable the kernel to trace every kernel function. This is done @@ -126,7 +137,7 @@ config IRQSOFF_TRACER depends on TRACE_IRQFLAGS_SUPPORT depends on GENERIC_TIME select TRACE_IRQFLAGS - select TRACING + select GENERIC_TRACER select TRACER_MAX_TRACE help This option measures the time spent in irqs-off critical @@ -147,7 +158,7 @@ config PREEMPT_TRACER default n depends on GENERIC_TIME depends on PREEMPT - select TRACING + select GENERIC_TRACER select TRACER_MAX_TRACE help This option measures the time spent in preemption off critical @@ -166,7 +177,7 @@ config PREEMPT_TRACER config SYSPROF_TRACER bool "Sysprof Tracer" depends on X86 - select TRACING + select GENERIC_TRACER select CONTEXT_SWITCH_TRACER help This tracer provides the trace needed by the 'Sysprof' userspace @@ -174,7 +185,7 @@ config SYSPROF_TRACER config SCHED_TRACER bool "Scheduling Latency Tracer" - select TRACING + select GENERIC_TRACER select CONTEXT_SWITCH_TRACER select TRACER_MAX_TRACE help @@ -183,6 +194,7 @@ config SCHED_TRACER config ENABLE_CONTEXT_SWITCH_TRACER bool "Trace process context switches" + depends on !GENERIC_TRACER select TRACING select CONTEXT_SWITCH_TRACER help @@ -191,6 +203,7 @@ config ENABLE_CONTEXT_SWITCH_TRACER config ENABLE_EVENT_TRACING bool "Trace various events in the kernel" + depends on !GENERIC_TRACER select TRACING help This tracer hooks to various trace points in the kernel @@ -204,14 +217,14 @@ config ENABLE_EVENT_TRACING config FTRACE_SYSCALLS bool "Trace syscalls" depends on HAVE_FTRACE_SYSCALLS - select TRACING + select GENERIC_TRACER select KALLSYMS help Basic tracer to catch the syscall entry and exit events. config BOOT_TRACER bool "Trace boot initcalls" - select TRACING + select GENERIC_TRACER select CONTEXT_SWITCH_TRACER help This tracer helps developers to optimize boot times: it records @@ -228,7 +241,7 @@ config BOOT_TRACER config TRACE_BRANCH_PROFILING bool - select TRACING + select GENERIC_TRACER choice prompt "Branch Profiling" @@ -308,7 +321,7 @@ config BRANCH_TRACER config POWER_TRACER bool "Trace power consumption behavior" depends on X86 - select TRACING + select GENERIC_TRACER help This tracer helps developers to analyze and optimize the kernels power management decisions, specifically the C-state and P-state @@ -342,14 +355,14 @@ config STACK_TRACER config HW_BRANCH_TRACER depends on HAVE_HW_BRANCH_TRACER bool "Trace hw branches" - select TRACING + select GENERIC_TRACER help This tracer records all branches on the system in a circular buffer giving access to the last N branches for each cpu. config KMEMTRACE bool "Trace SLAB allocations" - select TRACING + select GENERIC_TRACER help kmemtrace provides tracing for slab allocator functions, such as kmalloc, kfree, kmem_cache_alloc, kmem_cache_free etc.. Collected @@ -369,7 +382,7 @@ config KMEMTRACE config WORKQUEUE_TRACER bool "Trace workqueues" - select TRACING + select GENERIC_TRACER help The workqueue tracer provides some statistical informations about each cpu workqueue thread such as the number of the @@ -385,7 +398,7 @@ config BLK_DEV_IO_TRACE select RELAY select DEBUG_FS select TRACEPOINTS - select TRACING + select GENERIC_TRACER select STACKTRACE help Say Y here if you want to be able to trace the block layer actions @@ -446,7 +459,7 @@ config FTRACE_SELFTEST config FTRACE_STARTUP_TEST bool "Perform a startup test on ftrace" - depends on TRACING + depends on GENERIC_TRACER select FTRACE_SELFTEST help This option performs a series of startup tests on ftrace. On bootup @@ -457,7 +470,7 @@ config FTRACE_STARTUP_TEST config MMIOTRACE bool "Memory mapped IO tracing" depends on HAVE_MMIOTRACE_SUPPORT && PCI - select TRACING + select GENERIC_TRACER help Mmiotrace traces Memory Mapped I/O access and is meant for debugging and reverse engineering. It is called from the ioremap From 897f17a65389a26509bd0c79a9812d1c9ea8ea6f Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Thu, 28 May 2009 16:31:21 -0400 Subject: [PATCH 03/10] tracing: combine the default tracers into one config Both event tracer and sched switch plugin are selected by default by all generic tracers. But if no generic tracer is enabled, their options appear. But ether one of them will select the other, thus it only makes sense to have the default tracers be selected by one option. [ Impact: clean up kconfig menu ] Signed-off-by: Steven Rostedt --- kernel/trace/Kconfig | 19 +++---------------- 1 file changed, 3 insertions(+), 16 deletions(-) diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index 6e55cc3ac49d..4a13e5a01ce3 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -192,27 +192,14 @@ config SCHED_TRACER This tracer tracks the latency of the highest priority task to be scheduled in, starting from the point it has woken up. -config ENABLE_CONTEXT_SWITCH_TRACER - bool "Trace process context switches" - depends on !GENERIC_TRACER - select TRACING - select CONTEXT_SWITCH_TRACER - help - This tracer gets called from the context switch and records - all switching of tasks. - -config ENABLE_EVENT_TRACING - bool "Trace various events in the kernel" +config ENABLE_DEFAULT_TRACERS + bool "Trace process context switches and events" depends on !GENERIC_TRACER select TRACING help This tracer hooks to various trace points in the kernel allowing the user to pick and choose which trace point they - want to trace. - - Note, all tracers enable event tracing. This option is - only a convenience to enable event tracing when no other - tracers are selected. + want to trace. It also includes the sched_switch tracer plugin. config FTRACE_SYSCALLS bool "Trace syscalls" From 6e25db44a7ad7eb380f4ec774ec00a8fcddea112 Mon Sep 17 00:00:00 2001 From: Li Zefan Date: Fri, 29 May 2009 11:24:59 +0800 Subject: [PATCH 04/10] tracing/events: fix a typo in __string() format output "tsize" should be "\tsize". Also remove the space before "__str_loc". Before: # cat tracing/events/irq/irq_handler_entry/format ... field:int irq; offset:12; size:4; field: __str_loc name; offset:16;tsize:2; ... After: # cat tracing/events/irq/irq_handler_entry/format ... field:int irq; offset:12; size:4; field:__str_loc name; offset:16; size:2; ... [ Impact: standardize __string field description in events format file ] Signed-off-by: Li Zefan Signed-off-by: Frederic Weisbecker Signed-off-by: Steven Rostedt --- include/trace/ftrace.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h index b4ec83ae711f..9276ec4f34de 100644 --- a/include/trace/ftrace.h +++ b/include/trace/ftrace.h @@ -209,8 +209,8 @@ ftrace_raw_output_##call(struct trace_iterator *iter, int flags) \ #undef __string #define __string(item, src) \ - ret = trace_seq_printf(s, "\tfield: __str_loc " #item ";\t" \ - "offset:%u;tsize:%u;\n", \ + ret = trace_seq_printf(s, "\tfield:__str_loc " #item ";\t" \ + "offset:%u;\tsize:%u;\n", \ (unsigned int)offsetof(typeof(field), \ __str_loc_##item), \ (unsigned int)sizeof(field.__str_loc_##item)); \ From a9c1c3abe1160a5632e48c929b02b740556bf423 Mon Sep 17 00:00:00 2001 From: Li Zefan Date: Mon, 1 Jun 2009 15:35:13 +0800 Subject: [PATCH 05/10] tracing/events: put TP_fast_assign into braces Currently TP_fast_assign has a limitation that we can't define local variables in it. Here's one use case when we introduce __dynamic_array(): TP_fast_assign( type *p = __get_dynamic_array(item); foo(p); bar(p); ), [ Impact: allow defining local variables in TP_fast_assign ] Signed-off-by: Li Zefan LKML-Reference: <4A2384B1.90100@cn.fujitsu.com> Signed-off-by: Steven Rostedt --- include/trace/ftrace.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h index 9276ec4f34de..ee9268222448 100644 --- a/include/trace/ftrace.h +++ b/include/trace/ftrace.h @@ -471,7 +471,7 @@ static void ftrace_raw_event_##call(proto) \ return; \ entry = ring_buffer_event_data(event); \ \ - assign; \ + { assign; } \ \ if (!filter_current_check_discard(event_call, entry, event)) \ trace_nowake_buffer_unlock_commit(event, irq_flags, pc); \ From 7fcb7c472f455d1711eb5a7633204dba8800a6d6 Mon Sep 17 00:00:00 2001 From: Li Zefan Date: Mon, 1 Jun 2009 15:35:46 +0800 Subject: [PATCH 06/10] tracing/events: introduce __dynamic_array() __string() is limited: - it's a char array, but we may want to define array with other types - a source string should be available, but we may just know the string size We introduce __dynamic_array() to break those limitations, and __string() becomes a wrapper of it. As a side effect, now __get_str() can be used in TP_fast_assign but not only TP_print. Take XFS for example, we have the string length in the dirent, but the string itself is not NULL-terminated, so __dynamic_array() can be used: TRACE_EVENT(xfs_dir2, TP_PROTO(struct xfs_da_args *args), TP_ARGS(args), TP_STRUCT__entry( __field(int, namelen) __dynamic_array(char, name, args->namelen + 1) ... ), TP_fast_assign( char *name = __get_str(name); if (args->namelen) memcpy(name, args->name, args->namelen); name[args->namelen] = '\0'; __entry->namelen = args->namelen; ), TP_printk("name %.*s namelen %d", __entry->namelen ? __get_str(name) : NULL __entry->namelen) ); [ Impact: allow defining dynamic size arrays ] Signed-off-by: Li Zefan LKML-Reference: <4A2384D2.3080403@cn.fujitsu.com> Signed-off-by: Steven Rostedt --- include/trace/ftrace.h | 126 ++++++++++++++++++++--------- kernel/trace/trace_events_filter.c | 6 +- 2 files changed, 93 insertions(+), 39 deletions(-) diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h index ee9268222448..b5478dab579b 100644 --- a/include/trace/ftrace.h +++ b/include/trace/ftrace.h @@ -18,14 +18,17 @@ #include -#undef __array -#define __array(type, item, len) type item[len]; - #undef __field #define __field(type, item) type item; +#undef __array +#define __array(type, item, len) type item[len]; + +#undef __dynamic_array +#define __dynamic_array(type, item, len) unsigned short __data_loc_##item; + #undef __string -#define __string(item, src) unsigned short __str_loc_##item; +#define __string(item, src) __dynamic_array(char, item, -1) #undef TP_STRUCT__entry #define TP_STRUCT__entry(args...) args @@ -35,7 +38,7 @@ struct ftrace_raw_##name { \ struct trace_entry ent; \ tstruct \ - char __str_data[0]; \ + char __data[0]; \ }; \ static struct ftrace_event_call event_##name @@ -47,30 +50,31 @@ * * Include the following: * - * struct ftrace_str_offsets_ { - * int ; - * int ; + * struct ftrace_data_offsets_ { + * int ; + * int ; * [...] * }; * - * The __string() macro will create each int , this is to - * keep the offset of each string from the beggining of the event - * once we perform the strlen() of the src strings. - * + * The __dynamic_array() macro will create each int , this is + * to keep the offset of each array from the beginning of the event. */ -#undef __array -#define __array(type, item, len) - #undef __field #define __field(type, item); +#undef __array +#define __array(type, item, len) + +#undef __dynamic_array +#define __dynamic_array(type, item, len) int item; + #undef __string -#define __string(item, src) int item; +#define __string(item, src) __dynamic_array(char, item, -1) #undef TRACE_EVENT #define TRACE_EVENT(call, proto, args, tstruct, assign, print) \ - struct ftrace_str_offsets_##call { \ + struct ftrace_data_offsets_##call { \ tstruct; \ }; @@ -119,8 +123,12 @@ #undef TP_printk #define TP_printk(fmt, args...) fmt "\n", args +#undef __get_dynamic_array +#define __get_dynamic_array(field) \ + ((void *)__entry + __entry->__data_loc_##field) + #undef __get_str -#define __get_str(field) ((char *)__entry + __entry->__str_loc_##field) +#define __get_str(field) (char *)__get_dynamic_array(field) #undef __print_flags #define __print_flags(flag, delim, flag_array...) \ @@ -207,16 +215,19 @@ ftrace_raw_output_##call(struct trace_iterator *iter, int flags) \ if (!ret) \ return 0; -#undef __string -#define __string(item, src) \ - ret = trace_seq_printf(s, "\tfield:__str_loc " #item ";\t" \ +#undef __dynamic_array +#define __dynamic_array(type, item, len) \ + ret = trace_seq_printf(s, "\tfield:__data_loc " #item ";\t" \ "offset:%u;\tsize:%u;\n", \ (unsigned int)offsetof(typeof(field), \ - __str_loc_##item), \ - (unsigned int)sizeof(field.__str_loc_##item)); \ + __data_loc_##item), \ + (unsigned int)sizeof(field.__data_loc_##item)); \ if (!ret) \ return 0; +#undef __string +#define __string(item, src) __dynamic_array(char, item, -1) + #undef __entry #define __entry REC @@ -260,11 +271,14 @@ ftrace_format_##call(struct trace_seq *s) \ if (ret) \ return ret; +#undef __dynamic_array +#define __dynamic_array(type, item, len) \ + ret = trace_define_field(event_call, "__data_loc" "[" #type "]", #item,\ + offsetof(typeof(field), __data_loc_##item), \ + sizeof(field.__data_loc_##item), 0); + #undef __string -#define __string(item, src) \ - ret = trace_define_field(event_call, "__str_loc", #item, \ - offsetof(typeof(field), __str_loc_##item), \ - sizeof(field.__str_loc_##item), 0); +#define __string(item, src) __dynamic_array(char, item, -1) #undef TRACE_EVENT #define TRACE_EVENT(call, proto, args, tstruct, func, print) \ @@ -288,6 +302,43 @@ ftrace_define_fields_##call(void) \ #include TRACE_INCLUDE(TRACE_INCLUDE_FILE) +/* + * remember the offset of each array from the beginning of the event. + */ + +#undef __entry +#define __entry entry + +#undef __field +#define __field(type, item) + +#undef __array +#define __array(type, item, len) + +#undef __dynamic_array +#define __dynamic_array(type, item, len) \ + __data_offsets->item = __data_size + \ + offsetof(typeof(*entry), __data); \ + __data_size += (len) * sizeof(type); + +#undef __string +#define __string(item, src) __dynamic_array(char, item, strlen(src) + 1) \ + +#undef TRACE_EVENT +#define TRACE_EVENT(call, proto, args, tstruct, assign, print) \ +static inline int ftrace_get_offsets_##call( \ + struct ftrace_data_offsets_##call *__data_offsets, proto) \ +{ \ + int __data_size = 0; \ + struct ftrace_raw_##call __maybe_unused *entry; \ + \ + tstruct; \ + \ + return __data_size; \ +} + +#include TRACE_INCLUDE(TRACE_INCLUDE_FILE) + /* * Stage 4 of the trace events. * @@ -432,15 +483,15 @@ static void ftrace_profile_disable_##call(struct ftrace_event_call *event_call)\ #undef __array #define __array(type, item, len) +#undef __dynamic_array +#define __dynamic_array(type, item, len) \ + __entry->__data_loc_##item = __data_offsets.item; + #undef __string -#define __string(item, src) \ - __str_offsets.item = __str_size + \ - offsetof(typeof(*entry), __str_data); \ - __str_size += strlen(src) + 1; +#define __string(item, src) __dynamic_array(char, item, -1) \ #undef __assign_str #define __assign_str(dst, src) \ - __entry->__str_loc_##dst = __str_offsets.dst; \ strcpy(__get_str(dst), src); #undef TRACE_EVENT @@ -451,26 +502,29 @@ static struct ftrace_event_call event_##call; \ \ static void ftrace_raw_event_##call(proto) \ { \ - struct ftrace_str_offsets_##call __maybe_unused __str_offsets; \ + struct ftrace_data_offsets_##call __maybe_unused __data_offsets;\ struct ftrace_event_call *event_call = &event_##call; \ struct ring_buffer_event *event; \ struct ftrace_raw_##call *entry; \ unsigned long irq_flags; \ - int __str_size = 0; \ + int __data_size; \ int pc; \ \ local_save_flags(irq_flags); \ pc = preempt_count(); \ \ - tstruct; \ + __data_size = ftrace_get_offsets_##call(&__data_offsets, args); \ \ event = trace_current_buffer_lock_reserve(event_##call.id, \ - sizeof(struct ftrace_raw_##call) + __str_size,\ + sizeof(*entry) + __data_size, \ irq_flags, pc); \ if (!event) \ return; \ entry = ring_buffer_event_data(event); \ \ + \ + tstruct \ + \ { assign; } \ \ if (!filter_current_check_discard(event_call, entry, event)) \ diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c index a7430b16d243..db6e54bdb596 100644 --- a/kernel/trace/trace_events_filter.c +++ b/kernel/trace/trace_events_filter.c @@ -478,12 +478,12 @@ enum { static int is_string_field(const char *type) { + if (strstr(type, "__data_loc") && strstr(type, "char")) + return FILTER_DYN_STRING; + if (strchr(type, '[') && strstr(type, "char")) return FILTER_STATIC_STRING; - if (!strcmp(type, "__str_loc")) - return FILTER_DYN_STRING; - return 0; } From ec081ddc3d90aab35bc0de19a358b964978837cf Mon Sep 17 00:00:00 2001 From: Steven Whitehouse Date: Mon, 1 Jun 2009 15:53:35 +0100 Subject: [PATCH 07/10] tracing: add exports to use __print_symbolic and __print_flags from a module A patch to allow the use of __print_symbolic and __print_flags from a module. This allows the current GFS2 tracing patch to build. Signed-off-by: Steven Whitehouse LKML-Reference: <1243868015.29604.542.camel@localhost.localdomain> Signed-off-by: Steven Rostedt --- kernel/trace/trace_output.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c index c12d95db2f56..0fe3b223f7ed 100644 --- a/kernel/trace/trace_output.c +++ b/kernel/trace/trace_output.c @@ -17,6 +17,7 @@ static DECLARE_RWSEM(trace_event_mutex); DEFINE_PER_CPU(struct trace_seq, ftrace_event_seq); +EXPORT_PER_CPU_SYMBOL(ftrace_event_seq); static struct hlist_head event_hash[EVENT_HASHSIZE] __read_mostly; @@ -250,6 +251,7 @@ ftrace_print_flags_seq(struct trace_seq *p, const char *delim, return p->buffer; } +EXPORT_SYMBOL(ftrace_print_flags_seq); const char * ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val, @@ -275,6 +277,7 @@ ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val, return p->buffer; } +EXPORT_SYMBOL(ftrace_print_symbols_seq); #ifdef CONFIG_KRETPROBES static inline const char *kretprobed(const char *name) From 1d080d6c3141623c92caaebe20e847cb99ccbb60 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Mon, 1 Jun 2009 12:20:40 -0400 Subject: [PATCH 08/10] tracing: remove redundant SOFTIRQ from softirq event traces After converting the softirq tracer to use te flags options, this caused a regression with the name. Since the flag was used directly it was printed out (i.e. HRTIMER_SOFTIRQ). This patch only shows the softirq name without the SOFTIRQ part. [ Impact: fix regression of output from softirq events ] Signed-off-by: Steven Rostedt --- include/trace/events/irq.h | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-) diff --git a/include/trace/events/irq.h b/include/trace/events/irq.h index 683fb36a9943..b0c7ede55eb1 100644 --- a/include/trace/events/irq.h +++ b/include/trace/events/irq.h @@ -7,18 +7,18 @@ #undef TRACE_SYSTEM #define TRACE_SYSTEM irq -#define softirq_name(sirq) { sirq, #sirq } -#define show_softirq_name(val) \ - __print_symbolic(val, \ - softirq_name(HI_SOFTIRQ), \ - softirq_name(TIMER_SOFTIRQ), \ - softirq_name(NET_TX_SOFTIRQ), \ - softirq_name(NET_RX_SOFTIRQ), \ - softirq_name(BLOCK_SOFTIRQ), \ - softirq_name(TASKLET_SOFTIRQ), \ - softirq_name(SCHED_SOFTIRQ), \ - softirq_name(HRTIMER_SOFTIRQ), \ - softirq_name(RCU_SOFTIRQ)) +#define softirq_name(sirq) { sirq##_SOFTIRQ, #sirq } +#define show_softirq_name(val) \ + __print_symbolic(val, \ + softirq_name(HI), \ + softirq_name(TIMER), \ + softirq_name(NET_TX), \ + softirq_name(NET_RX), \ + softirq_name(BLOCK), \ + softirq_name(TASKLET), \ + softirq_name(SCHED), \ + softirq_name(HRTIMER), \ + softirq_name(RCU)) /** * irq_handler_entry - called immediately before the irq action handler From 112f38a7e36e9d688b389507136bf3af3e6d159b Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Mon, 1 Jun 2009 15:16:05 -0400 Subject: [PATCH 09/10] tracing: make trace pipe recognize latency format flag The trace_pipe did not recognize the latency format flag and would produce different output than the trace file. The problem was partly due that the trace flags in the iterator was not set as well as the trace_pipe zeros out part of the iterator (including the flags) to be able to use the same routines as the trace file. trace_flags of the iterator should not cause any problems when not zeroed out by for trace_pipe. Reported-by: Johannes Berg Signed-off-by: Steven Rostedt --- include/linux/ftrace_event.h | 2 +- kernel/trace/trace.c | 3 +++ 2 files changed, 4 insertions(+), 1 deletion(-) diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h index bbf40f624fc8..5c093ffc655b 100644 --- a/include/linux/ftrace_event.h +++ b/include/linux/ftrace_event.h @@ -51,6 +51,7 @@ struct trace_iterator { int cpu_file; struct mutex mutex; struct ring_buffer_iter *buffer_iter[NR_CPUS]; + unsigned long iter_flags; /* The below is zeroed out in pipe_read */ struct trace_seq seq; @@ -58,7 +59,6 @@ struct trace_iterator { int cpu; u64 ts; - unsigned long iter_flags; loff_t pos; long idx; diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index a3a8a87d7e91..cae34c69752f 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -2826,6 +2826,9 @@ static int tracing_open_pipe(struct inode *inode, struct file *filp) /* trace pipe does not show start of buffer */ cpumask_setall(iter->started); + if (trace_flags & TRACE_ITER_LATENCY_FMT) + iter->iter_flags |= TRACE_FILE_LAT_FMT; + iter->cpu_file = cpu_file; iter->tr = &global_trace; mutex_init(&iter->mutex); From 0f6ce3de4ef6ff940308087c49760d068851c1a7 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Mon, 1 Jun 2009 21:51:28 -0400 Subject: [PATCH 10/10] ftrace: do not profile functions when disabled A race was found that if one were to enable and disable the function profiler repeatedly, then the system can panic. This was because a profiled function may be preempted just before disabling interrupts. While the profiler is disabled and then reenabled, the preempted function could start again, and access the hash as it is being initialized. This just adds a check in the irq disabled part to check if the profiler is enabled, and if it is not then it will just exit. When the system is disabled, the profile_enabled variable is cleared before calling the unregistering of the function profiler. This unregistering calls stop machine which also acts as a synchronize schedule. [ Impact: fix panic in enabling/disabling function profiler ] Signed-off-by: Steven Rostedt --- kernel/trace/ftrace.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 2074e5b7766b..d6973dfadb36 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -599,7 +599,7 @@ function_profile_call(unsigned long ip, unsigned long parent_ip) local_irq_save(flags); stat = &__get_cpu_var(ftrace_profile_stats); - if (!stat->hash) + if (!stat->hash || !ftrace_profile_enabled) goto out; rec = ftrace_find_profiled_func(stat, ip); @@ -630,7 +630,7 @@ static void profile_graph_return(struct ftrace_graph_ret *trace) local_irq_save(flags); stat = &__get_cpu_var(ftrace_profile_stats); - if (!stat->hash) + if (!stat->hash || !ftrace_profile_enabled) goto out; calltime = trace->rettime - trace->calltime; @@ -724,6 +724,10 @@ ftrace_profile_write(struct file *filp, const char __user *ubuf, ftrace_profile_enabled = 1; } else { ftrace_profile_enabled = 0; + /* + * unregister_ftrace_profiler calls stop_machine + * so this acts like an synchronize_sched. + */ unregister_ftrace_profiler(); } }