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2009-06-04Merge branch 'tracing/ftrace' into tracing/coreIngo Molnar
Merge reason: this mini-topic had outstanding problems that delayed its merge, so it does not fast-forward. Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-06-01ftrace: do not profile functions when disabledSteven Rostedt
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 <rostedt@goodmis.org>
2009-06-01tracing: make trace pipe recognize latency format flagSteven Rostedt
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 <johannes@sipsolutions.net> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-06-01tracing: remove redundant SOFTIRQ from softirq event tracesSteven Rostedt
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 <rostedt@goodmis.org>
2009-06-01tracing: add exports to use __print_symbolic and __print_flags from a moduleSteven Whitehouse
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 <swhiteho@redhat.com> LKML-Reference: <1243868015.29604.542.camel@localhost.localdomain> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-06-01tracing/events: introduce __dynamic_array()Li Zefan
__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 <lizf@cn.fujitsu.com> LKML-Reference: <4A2384D2.3080403@cn.fujitsu.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-06-01tracing/events: put TP_fast_assign into bracesLi Zefan
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 <lizf@cn.fujitsu.com> LKML-Reference: <4A2384B1.90100@cn.fujitsu.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-06-01tracing/events: fix a typo in __string() format outputLi Zefan
"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 <lizf@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-06-01tracing: combine the default tracers into one configSteven Rostedt
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 <rostedt@goodmis.org>
2009-06-01tracing: fix config options to not show when automatically selectedSteven Rostedt
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 <rostedt@goodmis.org>
2009-06-01ftrace: add kernel command line function filteringSteven Rostedt
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 <rostedt@goodmis.org>
2009-06-02tracing/stat: remove unappropriate safe walk on listFrederic Weisbecker
register_stat_tracer() uses list_for_each_entry_safe to check whether a tracer is already present in the list. But we don't delete anything from the list here, so we don't need the safe version [ Impact: cleanup list use is stat tracing ] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-06-02tracing/stat: do some cleanupsLi Zefan
- remove duplicate code in stat_seq_init() - update comments to reflect the change from stat list to stat rbtree [ Impact: clean up ] Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-06-02tracing/stat: remember to free root nodeLi Zefan
When closing a trace_stat file, we destroy the rbtree constructed during file open, but there is memory leak that the root node is not freed. [ Impact: fix memory leak when closing a trace_stat file ] Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-06-02tracing/stat: change dummpy_cmp() to return -1Li Zefan
Currently the output of trace_stat/workqueues is totally reversed: # cat /debug/tracing/trace_stat/workqueues ... 1 17 17 210 37 `-blk_unplug_work+0x0/0x57 1 3779 3779 181 11 |-cfq_kick_queue+0x0/0x2f 1 3796 3796 kblockd/1:120 ... The correct output should be: 1 3796 3796 kblockd/1:120 1 3779 3779 181 11 |-cfq_kick_queue+0x0/0x2f 1 17 17 210 37 `-blk_unplug_work+0x0/0x57 It's caused by "tracing/stat: replace linked list by an rbtree for sorting" (53059c9b67a62a3dc8c80204d3da42b9267ea5a0). dummpy_cmp() should return -1, so rb_node will always be inserted as right-most node in the rbtree, thus we sort the output in ascending order. [ Impact: fix the output of trace_stat/workqueues ] Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-06-02tracing/stat: replace linked list by an rbtree for sortingFrederic Weisbecker
When the stat tracing framework prepares the entries from a tracer to output them to the user, it starts by computing a linear sort through a linked list to give the entries ordered by relevance to the user. This is quite ugly and causes a small latency when we begin to read the file. This patch changes that by turning the linked list into a red-black tree. Athough the whole iteration using the start and next tracer callbacks while opening the file remain the same, it is now much more fast and scalable. The rbtree guarantees O(log(n)) insertions whereas a linked list with linear sorting brought us a O(n) despair. Now the (visible) latency has disapeared. [ Impact: kill the latency while starting to read a stat tracer file ] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-06-02tracing/stat: replace trace_stat_session by stat_sessionFrederic Weisbecker
The "trace" prefix in struct trace_stat_session type is annoying while reading the trace_stat.c file. It makes the lines longer, and is not that much useful to explain the sense of this type. Just keep "struct stat_session" for this type. [ Impact: make the code a bit more readable ] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-06-02trace_workqueue: remove blank line between each cpuZhaolei
The blankline between each cpu's workqueue stat is not necessary, because the cpu number is enough to part them by eye. Old style also caused a blankline below headline, and made code complex by using lock, disableirq and get cpu var. Old style: # CPU INSERTED EXECUTED NAME # | | | | 0 8644 8644 events/0 0 0 0 cpuset ... 0 1 1 kdmflush 1 35365 35365 events/1 ... New style: # CPU INSERTED EXECUTED NAME # | | | | 0 8644 8644 events/0 0 0 0 cpuset ... 0 1 1 kdmflush 1 35365 35365 events/1 ... [ Impact: provide more readable code ] Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-06-02trace_workqueue: remove cpu_workqueue_stats->first_entryZhaolei
cpu_workqueue_stats->first_entry is useless because we can retrieve the header of a cpu workqueue using: if (&cpu_workqueue_stats->list == workqueue_cpu_stat(cpu)->list.next) [ Impact: cleanup ] Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-06-02trace_workqueue: use list_for_each_entry() instead of list_for_each_entry_safe()Zhaolei
No need to use list_for_each_entry_safe() in iteration without deleting any node, we can use list_for_each_entry() instead. [ Impact: cleanup ] Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-06-02ftrace, workqueuetrace: make workqueue tracepoints use TRACE_EVENT macroZhaolei
v3: zhaolei@cn.fujitsu.com: Change TRACE_EVENT definition to new format introduced by Steven Rostedt: consolidate trace and trace_event headers v2: kosaki@jp.fujitsu.com: print the function names instead of addr, and zap the work addr v1: zhaolei@cn.fujitsu.com: Make workqueue tracepoints use TRACE_EVENT macro TRACE_EVENT is a more generic way to define tracepoints. Doing so adds these new capabilities to the tracepoints: - zero-copy and per-cpu splice() tracing - binary tracing without printf overhead - structured logging records exposed under /debug/tracing/events - trace events embedded in function tracer output and other plugins - user-defined, per tracepoint filter expressions Then, this patch converts DEFINE_TRACE to TRACE_EVENT in workqueue related tracepoints. [ Impact: expand workqueue tracer to events tracing ] Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-05-28ftrace: don't convert function's local variable name in macroZhaolei
"call" is an argument of macro, but it is also used as a local variable name of function in macro. We should keep this local variable name distinct from any CPP macro parameter name if both are in the same macro scope, although it hasn't caused any problem yet. [ Impact: robustify macro ] Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-05-28trace: disable preemption before taking raw spinlocksHeiko Carstens
s390 code uses smp_processor_id() in __raw_spin_lock() code which reveals that a (raw) spinlock is taken without preemption disabled. This can potentially deadlock. To fix this explicitly disable and enable preemption. BUG: using smp_processor_id() in preemptible [00000000] code: cat/2278 caller is trace_find_cmdline+0x40/0xfc CPU: 0 Not tainted 2.6.30-rc7-dirty #39 Process cat (pid: 2278, task: 000000003faedb68, ksp: 000000003b33b988) 000000003b33b988 000000003b33bae0 0000000000000002 0000000000000000 000000003b33bb80 000000003b33baf8 000000003b33baf8 00000000000175d6 0000000000000001 000000003b33b988 000000003f9b0000 000000000000000b 000000000000000c 000000003b33bb40 000000003b33bae0 0000000000000000 0000000000000000 00000000000175d6 000000003b33bae0 000000003b33bb28 Call Trace: ([<00000000000174b2>] show_trace+0x112/0x170) [<0000000000017582>] show_stack+0x72/0x100 [<0000000000441538>] dump_stack+0xc8/0xd8 [<000000000025c350>] debug_smp_processor_id+0x114/0x130 [<00000000000bf0e4>] trace_find_cmdline+0x40/0xfc [<00000000000c35d4>] trace_print_context+0x58/0xac [<00000000000bb676>] print_trace_line+0x416/0x470 [<00000000000bc8fe>] s_show+0x4e/0x428 [<000000000013834e>] seq_read+0x36a/0x5d4 [<0000000000112a78>] vfs_read+0xc8/0x174 [<0000000000112c58>] SyS_read+0x74/0xc4 [<000000000002c7ae>] sysc_noemu+0x10/0x16 [<000002000012436c>] 0x2000012436c 1 lock held by cat/2278: #0: (&p->lock){+.+.+.}, at: [<0000000000138056>] seq_read+0x72/0x5d4 [ Impact: fix preempt-unsafe raw spinlock ] Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-05-26tracing: convert irq events to use __print_symbolicSteven Rostedt
The recording of the names at trace time is inefficient. This patch implements the softirq event recording to only record the vector and then use the __print_symbolic interface to print out the names. [ Impact: faster recording of softirq events ] Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-05-26tracing: add __print_symbolic to trace eventsSteven Rostedt
This patch adds __print_symbolic which is similar to __print_flags but works for an enumeration type instead. That is, there is only a one to one mapping between the values and the symbols. When a match is made, then it is printed, otherwise the hex value is outputed. [ Impact: add interface for showing symbol names in events ] Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-05-26tracing: add flag output for kmem eventsSteven Rostedt
This patch changes the output for gfp_flags from being a simple hex value to the actual names. gfp_flags=GFP_ATOMIC instead of gfp_flags=00000020 And even gfp_flags=GFP_KERNEL instead of gfp_flags=000000d0 (Thanks to Frederic Weisbecker for pointing out that the first version had a bad order of GFP masks) [ Impact: more human readable output from tracer ] Acked-by: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-05-26tracing: add previous task state info to sched switch eventSteven Rostedt
It is useful to see the state of a task that is being switched out. This patch adds the output of the state of the previous task in the context switch event. [ Impact: see state of switched out task in context switch ] Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-05-26tracing: add __print_flags for eventsSteven Rostedt
Developers have been asking for the ability in the ftrace event tracer to display names of bits in a flags variable. Instead of printing out c2, it would be easier to read FOO|BAR|GOO, assuming that FOO is bit 1, BAR is bit 6 and GOO is bit 7. Some examples where this would be useful are the state flags in a context switch, kmalloc flags, and even permision flags in accessing files. [ v2 changes include: Frederic Weisbecker's idea of using a mask instead of bits, thus we can output GFP_KERNEL instead of GPF_WAIT|GFP_IO|GFP_FS. Li Zefan's idea of allowing the caller of __print_flags to add their own delimiter (or no delimiter) where we can get for file permissions rwx instead of r|w|x. ] [ v3 changes: Christoph Hellwig's idea of using an array instead of va_args. ] [ Impact: better displaying of flags in trace output ] Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-05-26ftrace: clean up of using ftrace_event_enable_disable()Zhaolei
Always use ftrace_event_enable_disable() to enable/disable an event so that we can factorize out the event toggling code. [ Impact: factorize and cleanup event tracing code ] Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> LKML-Reference: <4A14FDFE.2080402@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-05-26ftrace: Add task_comm support for trace_eventZhaolei
If we enable a trace event alone without any tracer running (such as function tracer, sched switch tracer, etc...) it can't output enough task command information. We need to use the tracing_{start/stop}_cmdline_record() helpers which are designed to keep track of cmdlines for any tasks that were scheduled during the tracing. Before this patch: # echo 1 > debugfs/tracing/events/sched/sched_switch/enable # cat debugfs/tracing/trace # tracer: nop # # TASK-PID CPU# TIMESTAMP FUNCTION # | | | | | <...>-2289 [000] 526276.724790: sched_switch: task bash:2289 [120] ==> sshd:2287 [120] <...>-2287 [000] 526276.725231: sched_switch: task sshd:2287 [120] ==> bash:2289 [120] <...>-2289 [000] 526276.725452: sched_switch: task bash:2289 [120] ==> sshd:2287 [120] <...>-2287 [000] 526276.727181: sched_switch: task sshd:2287 [120] ==> swapper:0 [140] <idle>-0 [000] 526277.032734: sched_switch: task swapper:0 [140] ==> events/0:5 [115] <...>-5 [000] 526277.032782: sched_switch: task events/0:5 [115] ==> swapper:0 [140] ... After this patch: # tracer: nop # # TASK-PID CPU# TIMESTAMP FUNCTION # | | | | | bash-2269 [000] 527347.989229: sched_switch: task bash:2269 [120] ==> sshd:2267 [120] sshd-2267 [000] 527347.990960: sched_switch: task sshd:2267 [120] ==> bash:2269 [120] bash-2269 [000] 527347.991143: sched_switch: task bash:2269 [120] ==> sshd:2267 [120] sshd-2267 [000] 527347.992959: sched_switch: task sshd:2267 [120] ==> swapper:0 [140] <idle>-0 [000] 527348.531989: sched_switch: task swapper:0 [140] ==> events/0:5 [115] events/0-5 [000] 527348.532115: sched_switch: task events/0:5 [115] ==> swapper:0 [140] ... Changelog: v1->v2: Update Kconfig to select CONTEXT_SWITCH_TRACER in ENABLE_EVENT_TRACING v2->v3: v2 can solve problem that was caused by config EVENT_TRACING alone, but when CONFIG_FTRACE is off and CONFIG_TRACING is selected by other config, compile fail happened again. This version solves it. [ Impact: fix incomplete output of event tracing ] Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <4A14FDFE.2080402@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-05-26kmemtrace: fix kernel parameter documentationPekka Enberg
The kmemtrace.enable kernel parameter no longer works. To enable kmemtrace at boot-time, you must pass "ftrace=kmemtrace" instead. [ Impact: remove obsolete kernel parameter documentation ] Cc: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro> Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi> LKML-Reference: <alpine.DEB.2.00.0905241112190.10296@rocky> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-05-26tracing/events: change the type of __str_loc_item to unsigned shortLi Zefan
When defining a dynamic size string, we add __str_loc_##item to the trace entry, and it stores the location of the actual string in entry->_str_data[] 'unsigned short' should be sufficient to store this information, thus we save 2 bytes per dyn-size string in the ring buffer. [ Impact: reduce memory occupied by dyn-size strings in ring buffer ] Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <4A14EDB6.2050507@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-05-25tracing: add trace_event_read_lock()Lai Jiangshan
I found that there is nothing to protect event_hash in ftrace_find_event(). Rcu protects the event hashlist but not the event itself while we use it after its extraction through ftrace_find_event(). This lack of a proper locking in this spot opens a race window between any event dereferencing and module removal. Eg: --Task A-- print_trace_line(trace) { event = find_ftrace_event(trace) --Task B-- trace_module_remove_events(mod) { list_trace_events_module(ev, mod) { unregister_ftrace_event(ev->event) { hlist_del(ev->event->node) list_del(....) } } } |--> module removed, the event has been dropped --Task A-- event->print(trace); // Dereferencing freed memory If the event retrieved belongs to a module and this module is concurrently removed, we may end up dereferencing a data from a freed module. RCU could solve this, but it would add latency to the kernel and forbid tracers output callbacks to call any sleepable code. So this fix converts 'trace_event_mutex' to a read/write semaphore, and adds trace_event_read_lock() to protect ftrace_find_event(). [ Impact: fix possible freed memory dereference in ftrace ] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <4A114806.7090302@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-05-20ftrace: fix check for return value of register_module_notifier in ↵Ming Lei
event_trace_init register_module_notifier() returns zero in the success case. So fix the inverted fail case check in trace events modules handler. [ Impact: fix spurious warning on ftrace initialization] Reported-by: Li Zefan <lizf@cn.fujitsu.com> Signed-off-by: Ming Lei <tom.leiming@gmail.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-05-19blktrace: remove debugfs entries on bad pathStefan Raspl
debugfs directory entries for devices are not removed on some of the failure pathes in do_blk_trace_setup(). One way to reproduce is to start blktrace on multiple devices with insufficient Vmalloc space: Devices will fail with a message like this: BLKTRACESETUP(2) /dev/sdu failed: 5/Input/output error If so, the respective entries in debugfs (e.g. /sys/kernel/debug/block/sdu) will remain and subsequent attempts to start blktrace on the respective devices will not succeed due to existing directories. [ Impact: fix /debug/tracing file cleanup corner case ] Signed-off-by: Stefan Raspl <stefan.raspl@linux.vnet.ibm.com> Acked-by: Li Zefan <lizf@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: schwidefsky@de.ibm.com Cc: heiko.carstens@de.ibm.com LKML-Reference: <4A1266CC.5040801@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-05-19tracing/events: Documentation updatesLi Zefan
- fix some typos - document the difference between '>' and '>>' - document the 'enable' toggle - remove section "Defining an event-enabled tracepoint", since it's out-dated and sample/trace_events/ already serves this purpose. v2: add "Updated by Li Zefan" [ Impact: make documentation up-to-date ] Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: "Theodore Ts'o" <tytso@mit.edu> LKML-Reference: <4A125503.5060406@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-05-18tracing: fix check for return value of register_module_notifierMing Lei
return zero should be correct, so fix it. [ Impact: eliminate incorrect syslog message ] Signed-off-by: Ming Lei <tom.leiming@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Acked-by: Li Zefan <lizf@cn.fujitsu.com> Cc: rostedt@goodmis.org LKML-Reference: <1242545498-7285-1-git-send-email-tom.leiming@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-05-18Merge commit 'v2.6.30-rc6' into tracing/coreIngo Molnar
Merge reason: we were on an -rc4 base, sync up to -rc6 Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-05-15Linux 2.6.30-rc6Linus Torvalds
2009-05-15Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6: PCI MSI: Fix MSI-X with NIU cards PCI: Fix pci-e port driver slot_reset bad default return value
2009-05-15Merge git://git.kernel.org/pub/scm/linux/kernel/git/holtmann/bluetooth-2.6Linus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/holtmann/bluetooth-2.6: Bluetooth: Don't trigger disconnect timeout for security mode 3 pairing Bluetooth: Don't use hci_acl_connect_cancel() for incoming connections Bluetooth: Fix wrong module refcount when connection setup fails Another case of me handling the fallout from Davem's unfortunate addiction to shuffleboard. Won't anybody think of the children? Join the anti-shuffleboard league today!
2009-05-15Merge branch 'drm-intel-next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/anholt/drm-intel * 'drm-intel-next' of git://git.kernel.org/pub/scm/linux/kernel/git/anholt/drm-intel: drm/i915: Add new GET_PIPE_FROM_CRTC_ID ioctl. drm/i915: Set HDMI hot plug interrupt enable for only the output in question. drm/i915: Include 965GME pci ID in IS_I965GM(dev) to match UMS. drm/i915: Use the GM45 VGA hotplug workaround on G45 as well. drm/i915: ignore LVDS on intel graphics systems that lie about having it drm/i915: sanity check IER at wait_request time drm/i915: workaround IGD i2c bus issue in kernel side (v2) drm/i915: Don't allow binding objects into the last page of the aperture. drm/i915: save/restore fence registers across suspend/resume drm/i915: x86 always has writeq. Add I915_READ64 for symmetry.
2009-05-15Merge branch 'upstream-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/libata-dev * 'upstream-linus' of ssh://master.kernel.org/pub/scm/linux/kernel/git/jgarzik/libata-dev: libata: Media rotation rate and form factor heuristics libata: Report disk alignment and physical block size sata_fsl: Fix the command description of FSL SATA controller sata_fsl: Fix compile warnings [libata] sata_sx4: fixup interrupt handling [libata] sata_sx4: convert to new exception handling methods
2009-05-15Merge git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-2.6Linus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-2.6: iwlwifi: fix device id registration for 6000 series 2x2 devices ath5k: update channel in sw state after stopping RX and TX rtl8187: use DMA-aware buffers with usb_control_msg mac80211: avoid NULL ptr deref when finding max_rates in PID and minstrel airo: airo_get_encode{,ext} potential buffer overflow Pulled directly by Linus because Davem is off playing shuffle-board at some Alaskan cruise, and the NULL ptr deref issue hits people and should get merged sooner rather than later. David - make us proud on the shuffle-board tournament!
2009-05-15libata: Media rotation rate and form factor heuristicsMartin K. Petersen
This patch provides new heuristics for parsing both the form factor and media rotation rate ATA IDENFITY words. The reported ATA version must be 7 or greater and the device must return values defined as valid in the standard. Only then are the characteristics reported to SCSI via the VPD B1 page. This seems like a reasonable compromise to me considering that we have been shipping several kernel releases that key off the rotation rate bit without any version checking whatsoever. With no complaints so far. Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-05-15libata: Report disk alignment and physical block sizeMartin K. Petersen
For disks with 4KB sectors, report the correct block size and alignment when filling out the READ CAPACITY(16) response. This patch is based upon code from Matthew Wilcox' 4KB ATA tree. I fixed the bug I reported a while back caused by ATA and SCSI using different approaches to describing the alignment. Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-05-15sata_fsl: Fix the command description of FSL SATA controllerDave Liu
The bit 11 of command description is reserved bit in Freescale SATA controller and needs to be set to '1'. This is needed to make sure the last write from the controller to the buffer descriptor is seen before an interrupt is raised. Signed-off-by: Dave Liu <daveliu@freescale.com> Signed-off-by: Kumar Gala <galak@kernel.crashing.org> Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-05-15sata_fsl: Fix compile warningsKumar Gala
We we build with dma_addr_t as a 64-bit quantity we get: drivers/ata/sata_fsl.c: In function 'sata_fsl_fill_sg': drivers/ata/sata_fsl.c:340: warning: format '%x' expects type 'unsigned int', but argument 4 has type 'dma_addr_t' Signed-off-by: Kumar Gala <galak@kernel.crashing.org> Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-05-15[libata] sata_sx4: fixup interrupt handlingDavid Milburn
Issuing ATA_CMD_SET_FEATURES (0xef) times out because pdc20621_interrupt ignores command completion since ATA_TFLAG_POLLING flag is set. This has already been fixed for sata_promise: commit 51b94d2a5a90d4800e74d7348bcde098a28f4fb3 Author: Tejun Heo <htejun@gmail.com> Date: Fri Jun 8 13:46:55 2007 -0700 sata_promise: use TF interface for polling NODATA commands Also, this patch includes Mikael's original patches: http://marc.info/?l=linux-ide&m=121135828227724&w=2 http://marc.info/?l=linux-ide&m=121144512109826&w=2 Signed-off-by: Mikael Pettersson <mikpe@it.uu.se> Signed-off-by: David Milburn <dmilburn@redhat.com> Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-05-15[libata] sata_sx4: convert to new exception handling methodsJeff Garzik
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>