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* tracing: add format file to describe event struct fieldsSteven Rostedt2009-03-02
| | | | | | | | | | | | | | | | | This patch adds the "format" file to the trace point event directory. This is based off of work by Tom Zanussi, in which a file is exported to be tread from user land such that a user space app may read the binary record stored in the ring buffer. # cat /debug/tracing/events/sched/sched_switch/format field:pid_t prev_pid; offset:12; size:4; field:int prev_prio; offset:16; size:4; field special:char next_comm[TASK_COMM_LEN]; offset:20; size:16; field:pid_t next_pid; offset:36; size:4; field:int next_prio; offset:40; size:4; Idea-from: Tom Zanussi <tzanussi@gmail.com> Signed-off-by: Steven Rostedt <srostedt@redhat.com>
* tracing: make trace_seq_reset global and rename to trace_seq_initSteven Rostedt2009-03-02
| | | | | | | | | | | | Impact: clean up The trace_seq functions may be used separately outside of the ftrace iterator. The trace_seq_reset is needed for these operations. This patch also renames trace_seq_reset to the more appropriate trace_seq_init. Signed-off-by: Steven Rostedt <srostedt@redhat.com>
* tracing: add protection around modify trace event fieldsSteven Rostedt2009-03-02
| | | | | | | | The trace event objects are currently not proctected against reentrancy. This patch adds a mutex around the modifications of the trace event fields. Signed-off-by: Steven Rostedt <srostedt@redhat.com>
* tracing: add TRACE_FIELD_SPECIAL to record complex entriesSteven Rostedt2009-03-02
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Tom Zanussi pointed out that the simple TRACE_FIELD was not enough to record trace data that required memcpy. This patch addresses this issue by adding a TRACE_FIELD_SPECIAL. The format is similar to TRACE_FIELD but looks like so: TRACE_FIELD_SPECIAL(type_item, item, cmd) What TRACE_FIELD gave was: TRACE_FIELD(type, item, assign) The TRACE_FIELD would be used in declaring a structure: struct { type item; }; And later assign it via: entry->item = assign; What TRACE_FIELD_SPECIAL gives us is: In the declaration of the structure: struct { type_item; }; And the assignment: cmd; This change log will explain the one example used in the patch: TRACE_EVENT_FORMAT(sched_switch, TPPROTO(struct rq *rq, struct task_struct *prev, struct task_struct *next), TPARGS(rq, prev, next), TPFMT("task %s:%d ==> %s:%d", prev->comm, prev->pid, next->comm, next->pid), TRACE_STRUCT( TRACE_FIELD(pid_t, prev_pid, prev->pid) TRACE_FIELD(int, prev_prio, prev->prio) TRACE_FIELD_SPECIAL(char next_comm[TASK_COMM_LEN], next_comm, TPCMD(memcpy(TRACE_ENTRY->next_comm, next->comm, TASK_COMM_LEN))) TRACE_FIELD(pid_t, next_pid, next->pid) TRACE_FIELD(int, next_prio, next->prio) ), TPRAWFMT("prev %d:%d ==> next %s:%d:%d") ); The struct will be create as: struct { pid_t prev_pid; int prev_prio; char next_comm[TASK_COMM_LEN]; pid_t next_pid; int next_prio; }; Note the TRACE_ENTRY in the cmd part of TRACE_SPECIAL. TRACE_ENTRY will be set by the tracer to point to the structure inside the trace buffer. entry->prev_pid = prev->pid; entry->prev_prio = prev->prio; memcpy(entry->next_comm, next->comm, TASK_COMM_LEN); entry->next_pid = next->pid; entry->next_prio = next->prio Reported-by: Tom Zanussi <tzanussi@gmail.com> Signed-off-by: Steven Rostedt <srostedt@redhat.com>
* tracing: create the C style tracing for the irq subsystemSteven Rostedt2009-02-28
| | | | | | | This patch utilizes the TRACE_EVENT_FORMAT macro to enable the C style faster tracing for the irq subsystem trace points. Signed-off-by: Steven Rostedt <srostedt@redhat.com>
* tracing: create the C style tracing for the sched subsystemSteven Rostedt2009-02-28
| | | | | | | This patch utilizes the TRACE_EVENT_FORMAT macro to enable the C style faster tracing for the sched subsystem trace points. Signed-off-by: Steven Rostedt <srostedt@redhat.com>
* tracing: add raw fast tracing interface for trace eventsSteven Rostedt2009-02-28
| | | | | | | | | | | | | | | | | | | | | | | | | This patch adds the interface to enable the C style trace points. In the directory /debugfs/tracing/events/subsystem/event We now have three files: enable : values 0 or 1 to enable or disable the trace event. available_types: values 'raw' and 'printf' which indicate the tracing types available for the trace point. If a developer does not use the TRACE_EVENT_FORMAT macro and just uses the TRACE_FORMAT macro, then only 'printf' will be available. This file is read only. type: values 'raw' or 'printf'. This indicates which type of tracing is active for that trace point. 'printf' is the default and if 'raw' is not available, this file is read only. # echo raw > /debug/tracing/events/sched/sched_wakeup/type # echo 1 > /debug/tracing/events/sched/sched_wakeup/enable Will enable the C style tracing for the sched_wakeup trace point. Signed-off-by: Steven Rostedt <srostedt@redhat.com>
* tracing: add raw trace point recording infrastructureSteven Rostedt2009-02-28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: lower overhead tracing The current event tracer can automatically pick up trace points that are registered with the TRACE_FORMAT macro. But it required a printf format string and parsing. Although, this adds the ability to get guaranteed information like task names and such, it took a hit in overhead processing. This processing can add about 500-1000 nanoseconds overhead, but in some cases that too is considered too much and we want to shave off as much from this overhead as possible. Tom Zanussi recently posted tracing patches to lkml that are based on a nice idea about capturing the data via C structs using STRUCT_ENTER, STRUCT_EXIT type of macros. I liked that method very much, but did not like the implementation that required a developer to add data/code in several disjoint locations. This patch extends the event_tracer macros to do a similar "raw C" approach that Tom Zanussi did. But instead of having the developers needing to tweak a bunch of code all over the place, they can do it all in one macro - preferably placed near the code that it is tracing. That makes it much more likely that tracepoints will be maintained on an ongoing basis by the code they modify. The new macro TRACE_EVENT_FORMAT is created for this approach. (Note, a developer may still utilize the more low level DECLARE_TRACE macros if they don't care about getting their traces automatically in the event tracer.) They can also use the existing TRACE_FORMAT if they don't need to code the tracepoint in C, but just want to use the convenience of printf. So if the developer wants to "hardwire" a tracepoint in the fastest possible way, and wants to acquire their data via a user space utility in a raw binary format, or wants to see it in the trace output but not sacrifice any performance, then they can implement the faster but more complex TRACE_EVENT_FORMAT macro. Here's what usage looks like: TRACE_EVENT_FORMAT(name, TPPROTO(proto), TPARGS(args), TPFMT(fmt, fmt_args), TRACE_STUCT( TRACE_FIELD(type1, item1, assign1) TRACE_FIELD(type2, item2, assign2) [...] ), TPRAWFMT(raw_fmt) ); Note name, proto, args, and fmt, are all identical to what TRACE_FORMAT uses. name: is the unique identifier of the trace point proto: The proto type that the trace point uses args: the args in the proto type fmt: printf format to use with the event printf tracer fmt_args: the printf argments to match fmt TRACE_STRUCT starts the ability to create a structure. Each item in the structure is defined with a TRACE_FIELD TRACE_FIELD(type, item, assign) type: the C type of item. item: the name of the item in the stucture assign: what to assign the item in the trace point callback raw_fmt is a way to pretty print the struct. It must match the order of the items are added in TRACE_STUCT An example of this would be: TRACE_EVENT_FORMAT(sched_wakeup, TPPROTO(struct rq *rq, struct task_struct *p, int success), TPARGS(rq, p, success), TPFMT("task %s:%d %s", p->comm, p->pid, success?"succeeded":"failed"), TRACE_STRUCT( TRACE_FIELD(pid_t, pid, p->pid) TRACE_FIELD(int, success, success) ), TPRAWFMT("task %d success=%d") ); This creates us a unique struct of: struct { pid_t pid; int success; }; And the way the call back would assign these values would be: entry->pid = p->pid; entry->success = success; The nice part about this is that the creation of the assignent is done via macro magic in the event tracer. Once the TRACE_EVENT_FORMAT is created, the developer will then have a faster method to record into the ring buffer. They do not need to worry about the tracer itself. The developer would only need to touch the files in include/trace/*.h Again, I would like to give special thanks to Tom Zanussi for this nice idea. Idea-from: Tom Zanussi <tzanussi@gmail.com> Signed-off-by: Steven Rostedt <srostedt@redhat.com>
* tracing: add interface to write into current tracer bufferSteven Rostedt2009-02-28
| | | | | | | | | | | | | Right now all tracers must manage their own trace buffers. This was to enforce tracers to be independent in case we finally decide to allow each tracer to have their own trace buffer. But now we are adding event tracing that writes to the current tracer's buffer. This adds an interface to allow events to write to the current tracer buffer without having to manage its own. Since event tracing has no "tracer", and is just a way to hook into any other tracer. Signed-off-by: Steven Rostedt <srostedt@redhat.com>
* tracing: add subsystem sched for sched eventsSteven Rostedt2009-02-28
| | | | | | Add the TRACE_SYSTEM sched for the sched events. Signed-off-by: Steven Rostedt <srostedt@redhat.com>
* tracing: add subsystem irq for irq eventsSteven Rostedt2009-02-28
| | | | | | Add the TRACE_SYSTEM irq for the irq events. Signed-off-by: Steven Rostedt <srostedt@redhat.com>
* tracing: make the set_event and available_events subsystem awareSteven Rostedt2009-02-28
| | | | | | | | | | | | | This patch makes the event files, set_event and available_events aware of the subsystem. Now you can enable an entire subsystem with: echo 'irq:*' > set_event Note: the '*' is not needed. Signed-off-by: Steven Rostedt <srostedt@redhat.com>
* tracing: add subsystem level to trace eventsSteven Rostedt2009-02-28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If a trace point header defines TRACE_SYSTEM, then it will add the following trace points into that event system. If include/trace/irq_event_types.h has: #define TRACE_SYSTEM irq at the top and #undef TRACE_SYSTEM at the bottom, then a directory "irq" will be created in the /debug/tracing/events directory. Inside that directory will contain the two trace points that are defined in include/trace/irq_event_types.h. Only adding the above to irq and not to sched, we get: # ls /debug/tracing/events/ irq sched_process_exit sched_signal_send sched_wakeup_new sched_kthread_stop sched_process_fork sched_switch sched_kthread_stop_ret sched_process_free sched_wait_task sched_migrate_task sched_process_wait sched_wakeup # ls /debug/tracing/events/irq irq_handler_entry irq_handler_exit If we add #define TRACE_SYSTEM sched to the trace/sched_event_types.h then the rest of the trace events will be put in a sched directory within the events directory. I've been playing with this idea of the subsystem for a while, but recently Tom Zanussi posted some patches to lkml that included this method. Tom's approach was clean and got me to finally put some effort to clean up the event trace points. Thanks to Tom Zanussi for demonstrating how nice the subsystem method is. Signed-off-by: Steven Rostedt <srostedt@redhat.com>
* tracing: move trace point formats to files in include/trace directorySteven Rostedt2009-02-28
| | | | | | | | | | | | | | | | | | | | | | | | | Impact: clean up To further facilitate the ease of adding trace points for developers, this patch creates include/trace/trace_events.h and include/trace/trace_event_types.h. The former file will hold the trace/<type>.h files and the latter will hold the trace/<type>_event_types.h files. To create new tracepoints and to have them automatically appear in the event tracer, a developer makes the trace/<type>.h file which includes <linux/tracepoint.h> and the trace/<type>_event_types.h file. The trace/<type>_event_types.h file will hold the TRACE_FORMAT macros. Then add the trace/<type>.h file to trace/trace_events.h, and add the trace/<type>_event_types.h to the trace_event_types.h file. No need to modify files elsewhere. Signed-off-by: Steven Rostedt <srostedt@redhat.com>
* tracing: replace kzalloc with kcallocSteven Rostedt2009-02-27
| | | | | | | | | Impact: clean up kcalloc is a better approach to allocate a NULL array. Reported-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Steven Rostedt <srostedt@redhat.com>
* tracing: use newline separator for trace options listSteven Rostedt2009-02-27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: clean up Instead of listing the trace options like: # cat /debug/tracing/trace_options print-parent nosym-offset nosym-addr noverbose noraw nohex nobin noblock nostacktrace nosched-tree ftrace_printk noftrace_preempt nobranch annotate nouserstacktrace nosym-userobj We now list them like: # cat /debug/tracing/trace_options print-parent nosym-offset nosym-addr noverbose noraw nohex nobin noblock nostacktrace nosched-tree ftrace_printk noftrace_preempt nobranch annotate nouserstacktrace nosym-userobj Signed-off-by: Steven Rostedt <srostedt@redhat.com>
* tracing: use pointer error returns for __tracing_openSteven Rostedt2009-02-27
| | | | | | | | | | | | | | | | | | Impact: fix compile warning and clean up When I first wrote __tracing_open, instead of passing the error code via the ERR_PTR macros, I lazily used a separate parameter to hold the return for errors. When Frederic Weisbecker updated that function, he used the Linux kernel ERR_PTR for the returns. This caused the parameter return to possibly not be initialized on error. gcc correctly pointed this out with a warning. This patch converts the entire function to use the Linux kernel ERR_PTR macro methods. Signed-off-by: Steven Rostedt <srostedt@redhat.com>
* tracing: add protection around open use of current_tracerSteven Rostedt2009-02-26
| | | | | | | | | | | | | | Impact: fix to possible race conditions There's some uses of current_tracer that is not protected by the trace_types_lock. There is a small chance that a sysadmin changes the tracer while the current_tracer is being referenced. If the race is hit, it is unlikely to cause any harm since the tracers are constant and are not freed. But some strang side effects may occur. Signed-off-by: Steven Rostedt <srostedt@redhat.com>
* tracing: add tracer dependent options to options directorySteven Rostedt2009-02-26
| | | | | | | | This patch adds the tracer dependent options dynamically to the options directory when the tracer is activated. These options are removed when the tracer is deactivated. Signed-off-by: Steven Rostedt <srostedt@redhat.com>
* tracing: add options directory and core option filesSteven Rostedt2009-02-26
| | | | | | | | | | | This patch creates an options directory in the debugfs, that contains the available tracing options. These files contain 1 or 0, where 1 is the option is enabled and 0 it is disabled. Simply echoing in 1 will enable the option and 0 will disable it. This patch only contains the core options, not the tracer options. Signed-off-by: Steven Rostedt <srostedt@redhat.com>
* Merge branch 'sched/clock' into tracing/ftraceIngo Molnar2009-02-26
|\ | | | | | | | | Conflicts: kernel/sched_clock.c
| * x86: set X86_FEATURE_TSC_RELIABLEIngo Molnar2009-02-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If the TSC is constant and non-stop, also set it reliable. (We will turn this off in DMI quirks for multi-chassis systems) The performance number on a 16-way Nehalem system running 32 tasks that context-switch between each other is significant: sched_clock_stable=0 sched_clock_stable=1 .................... .................... 22.456925 million/sec 24.306972 million/sec [+8.2%] lmbench's "lat_ctx -s 0 2" goes from 0.63 microseconds to 0.59 microseconds - a 6.7% increase in context-switching performance. Perfstat of 1 million pipe context switches between two tasks: Performance counter stats for './pipe-test-1m': [before] [after] ............ ............ 37621.421089 36436.848378 task clock ticks (msecs) 0 0 CPU migrations (events) 2000274 2000189 context switches (events) 194 193 pagefaults (events) 8433799643 8171016416 CPU cycles (events) -3.21% 8370133368 8180999694 instructions (events) -2.31% 4158565 3895941 cache references (events) -6.74% 44312 46264 cache misses (events) 2349.287976 2279.362465 wall-time (msecs) -3.06% The speedup comes straight from the reduction in the instruction count. sched_clock_cpu() got simpler and the whole workload thus executes faster. Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * sched: allow architectures to specify sched_clock_stableIngo Molnar2009-02-26
| | | | | | | | | | | | | | | | | | | | Allow CONFIG_HAVE_UNSTABLE_SCHED_CLOCK architectures to still specify that their sched_clock() implementation is reliable. This will be used by x86 to switch on a faster sched_clock_cpu() implementation on certain CPU types. Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | tracing: implement trace_clock_*() APIsIngo Molnar2009-02-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: implement new tracing timestamp APIs Add three trace clock variants, with differing scalability/precision tradeoffs: - local: CPU-local trace clock - medium: scalable global clock with some jitter - global: globally monotonic, serialized clock Make the ring-buffer use the local trace clock internally. Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | sched: sched_clock() improvement: use in_nmi()Ingo Molnar2009-02-26
| | | | | | | | | | | | | | | | make sure we dont execute more complex sched_clock() code in NMI context. Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | tracing, genirq: add irq enter and exit trace eventsJason Baron2009-02-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: add new tracepoints Add them to the generic IRQ code, that way every architecture gets these new tracepoints, not just x86. Using Steve's new 'TRACE_FORMAT', I can get function graph trace as follows using the original two IRQ tracepoints: 3) | handle_IRQ_event() { 3) | /* (irq_handler_entry) irq=28 handler=eth0 */ 3) | e1000_intr_msi() { 3) 2.460 us | __napi_schedule(); 3) 9.416 us | } 3) | /* (irq_handler_exit) irq=28 handler=eth0 return=handled */ 3) + 22.935 us | } Signed-off-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Mathieu Desnoyers <compudj@krystal.dyndns.org> Cc: "Frank Ch. Eigler" <fche@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | tracing/core: make the per cpu trace files in per cpu directoriesFrederic Weisbecker2009-02-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: restructure the VFS layout of per CPU trace buffers The per cpu trace files are all in a single directory: /debug/tracing/per_cpu. In case of a large number of cpu, the content of this directory becomes messy so we create now one directory per cpu inside /debug/tracing/per_cpu which contain each their own trace_pipe and trace files. Ie: /debug/tracing$ ls -R per_cpu per_cpu: cpu0 cpu1 per_cpu/cpu0: trace trace_pipe per_cpu/cpu1: trace trace_pipe Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | Merge branch 'tip/tracing/ftrace' of ↵Ingo Molnar2009-02-25
|\ \ | | | | | | | | | ssh://master.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace into tracing/ftrace
| * | tracing: wrap arguments with PARAMSSteven Rostedt2009-02-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Peter Zijlstra warned that TPPROTO and TPARGS might become something other than a simple copy of itself. To prevent this from having side effects in the TRACE_FORMAT macro in tracepoint.h, we add a PARAMS() macro to be defined as just a wrapper. Reported-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Steven Rostedt <srostedt@redhat.com>
| * | tracing: rename DEFINE_TRACE_FMT to just TRACE_FORMATSteven Rostedt2009-02-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | There's been a bit confusion to whether DEFINE/DECLARE_TRACE_FMT should be a DEFINE or a DECLARE. Ingo Molnar suggested simply calling it TRACE_FORMAT. Reported-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Steven Rostedt <srostedt@redhat.com>
| | |
| \ \
*-. \ \ Merge branches 'tracing/ftrace', 'tracing/hw-branch-tracing' and 'linus' ↵Ingo Molnar2009-02-25
|\ \ \ \ | |_|/ / |/| | / | | |/ into tracing/core
| | * Merge branch 'proc-linus' of ↵Linus Torvalds2009-02-24
| | |\ | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/adobriyan/proc * 'proc-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/adobriyan/proc: proc: fix PG_locked reporting in /proc/kpageflags
| | | * proc: fix PG_locked reporting in /proc/kpageflagsHelge Bahmann2009-02-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Expr always evaluates to zero. Cc: Matt Mackall <mpm@selenic.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
| | * | Merge branch 'i2c-for-linus' of git://jdelvare.pck.nerim.net/jdelvare-2.6Linus Torvalds2009-02-24
| | |\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * 'i2c-for-linus' of git://jdelvare.pck.nerim.net/jdelvare-2.6: Add i2c_board_info for RiscPC PCF8583 i2c: Make sure i2c_algo_bit_data.timeout is HZ-independent i2c-dev: Clarify the unit of ioctl I2C_TIMEOUT i2c: Timeouts reach -1 i2c: Fix misplaced parentheses
| | | * | Add i2c_board_info for RiscPC PCF8583Russell King2009-02-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add the necessary i2c_board_info structure to fix the lack of PCF8583 RTC on RiscPC. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: Alessandro Zummo <a.zummo@towertech.it>
| | | * | i2c: Make sure i2c_algo_bit_data.timeout is HZ-independentJean Delvare2009-02-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | i2c_algo_bit_data.timeout is supposed to be in jiffies, so drivers should use set this value in terms of HZ. Ultimately I think this field should be discarded in favor of i2c_adapter.timeout, but that's left for a future patch. Signed-off-by: Jean Delvare <khali@linux-fr.org> Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Acked-by: Lennert Buytenhek <kernel@wantstofly.org> Acked-by: Len Sorensen <lsorense@csclub.uwaterloo.ca>
| | | * | i2c-dev: Clarify the unit of ioctl I2C_TIMEOUTJean Delvare2009-02-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The unit in which user-space can set the bus timeout value is jiffies for historical reasons (back when HZ was always 100.) This is however not good because user-space doesn't know how long a jiffy lasts. The timeout value should instead be set in a fixed time unit. Given the original value of HZ, this unit should be 10 ms, for compatibility. Signed-off-by: Jean Delvare <khali@linux-fr.org> Acked-by: Wolfram Sang <w.sang@pengutronix.de>
| | | * | i2c: Timeouts reach -1Roel Kluin2009-02-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With a postfix decrement these timeouts reach -1 rather than 0, but after the loop it is tested whether they have become 0. As pointed out by Jean Delvare, the condition we are waiting for should also be tested before the timeout. With the current order, you could exit with a timeout error while the job is actually done. Signed-off-by: Roel Kluin <roel.kluin@gmail.com> Signed-off-by: Jean Delvare <khali@linux-fr.org>
| | | * | i2c: Fix misplaced parenthesesRoel Kluin2009-02-24
| | | |/ | | | | | | | | | | | | | | | | | | | | | | | | Fix misplaced parentheses. Signed-off-by: Roel Kluin <roel.kluin@gmail.com> Signed-off-by: Jean Delvare <khali@linux-fr.org>
| | * | Merge branch 'firedtv-merge' of ↵Linus Torvalds2009-02-24
| | |\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6 * 'firedtv-merge' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6: firedtv: dvb_frontend_info for FireDTV S2, fix "frequency limits undefined" error firedtv: massive refactoring firedtv: rename files, variables, functions from firesat to firedtv firedtv: Use DEFINE_SPINLOCK firedtv: fix registration - adapter number could only be zero firedtv: use length_field() of PMT as length firedtv: fix returned struct for ca_info firedtv: cleanups and minor fixes ieee1394: remove superfluous assertions ieee1394: inherit ud vendor_id from node vendor_id ieee1394: add hpsb_node_read() and hpsb_node_lock() ieee1394: use correct barrier types between accesses of nodeid and generation firesat: copyrights, rename to firedtv, API conversions, fix remote control input firesat: avc resend firesat: update isochronous interface, add CI support firesat: add DVB-S support for DVB-S2 devices firesat: fix DVB-S2 device recognition DVB: add firesat driver
| | | * | firedtv: dvb_frontend_info for FireDTV S2, fix "frequency limits undefined" ↵Beat Michel Liechti2009-02-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | error I found that the function fdtv_frontend_init in the file firedtv-fe.c was missing a case for FIREDTV_DVB_S2 which resulted in "frequency limits undefined" errors in syslog. Signed-off-by: Beat Michel Liechti <bml303@gmail.com> Change by Stefan R: combine it with case case FIREDTV_DVB_S as originally suggested by Beat Michel. This enables FE_CAN_FEC_AUTO also for FireDTV-S2 devices which is possible as long as only DVB-S channels are used. FE_CAN_FEC_AUTO would be wrong for DVB-S2 channels, but those cannot be used yet since the driver is not yet converted to S2API. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
| | | * | firedtv: massive refactoringStefan Richter2009-02-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Combination of the following changes: Mon, 23 Feb 2009 14:21:10 +0100 (CET) firedtv: reinstate debug logging option Henrik Kurelid tells me that FCP debug logging (which I removed during cleanups) is still useful when working on driver issues together with end users. So bring it back in an updated form with only 60% of the original code footprint. Logging can be enabled with # echo -1 > /sys/module/firedtv/parameters/debug 1 instead of -1 enables only FCP header logging, 2 instead of -1 enables only hexdumps of the entire FCP frames. 0 switches logging off again. Fri, 20 Feb 2009 20:54:27 +0100 (CET) firedtv: build fix for INPUT=m and DVB_FIREDTV=y Thu, 19 Feb 2009 20:40:39 +0100 firedtv: use msecs_to_jiffies Pointed out by Mauro Carvalho Chehab. Sun Feb 15 20:50:46 CET 2009 firedtv: some more housekeeping Fix an old checkpatch warning and a new compiler warning. Sun Feb 15 15:33:17 CET 2009 firedtv: rename a file once more At the moment, about a third of avc.c is specific to FireDTVs rather than generic AV/C code. Rename it to firedtv-avc.c. Sun Feb 15 15:33:17 CET 2009 firedtv: dvb demux: more compact channels backing store Replace struct firedtv_channel { bool active; int pid; } channel[16]; by unsigned long channel_active; u16 channel_pid[16];. Sun Feb 15 15:33:17 CET 2009 firedtv: dvb demux: some simplifications c->active was unnecessarily cleared twice. Also, by marking the channel inactive before the for loop, the loop becomes identical with fdtv_channel_collect(). Sun Feb 15 15:33:17 CET 2009 firedtv: dvb demux: remove a bogus loop This loop is unnecessary because - only active channel[].pid's will be sent to the device, - when a channel is activated, its pid is set to dvbdmxfeed->pid. Perhaps the original code was there because it was initially not fully covered by the fdtv->demux_mutex. Sun Feb 15 15:33:17 CET 2009 firedtv: dvb demux: fix mutex protection fdtv_start_feed() accessed the channel list unsafely. Fully serialize it with itself and fdtv_stop_feed(). Sun Feb 15 15:33:17 CET 2009 firedtv: dvb demux: fix missing braces Original code was: ... case DMX_TS_PES_OTHER: //Dirty fix to keep firesat->channel pid-list up to date for(k=0;k<16;k++){ if(firesat->channel[k].active == 0) firesat->channel[k].pid = dvbdmxfeed->pid; break; } channel = firesat_channel_allocate(firesat); break; default: ... Looks bogus in several respects. For now let's just add braces to the if because that seems to be what the author meant. Sun Feb 15 15:33:17 CET 2009 firedtv: allow build without input subsystem !CONFIG_INPUT is very unlikely on systems on which firedtv is of interest. But we can easily support it. Sun Feb 15 15:33:17 CET 2009 firedtv: replace EXTRA_CFLAGS by ccflags The former are deprecated. The latter can depend on Kconfig variables. Sun Feb 15 15:33:17 CET 2009 firedtv: concentrate ieee1394 dependencies Move the entire interface with drivers/ieee1394 to firedtv-1394.c. Move 1394-independent module initialization code to firedtv-dvb.c. This prepares interfacing with drivers/firewire. Sun Feb 15 15:33:17 CET 2009 firedtv: amend Kconfig menu prompt Sun Feb 15 15:33:17 CET 2009 firedtv: remove kernel version compatibility macro Sun Feb 15 15:33:17 CET 2009 firedtv: combine header files avc.h and firedtv-*.h are small and currently not shared with other drivers, hence concatenate them all into firedtv.h. Sun Feb 15 15:33:17 CET 2009 firedtv: misc style touch-ups Standardize on lower-case hexadecimal constants. Adjust whitespace. Omit unnecessary pointer type casts and an unnecessary list head initialization. Use dev_printk. Wed Feb 11 21:21:04 CET 2009 firedtv: avc, ci: remove unused constants Wed Feb 11 21:21:04 CET 2009 firedtv: avc: remove bitfields from read descriptor response operands Don't use bitfields in struct types of on-the-wire data. Wed Feb 11 21:21:04 CET 2009 firedtv: avc: remove bitfields from DSD command operands Don't use bitfields in struct types of on-the-wire data. Wed Feb 11 21:21:04 CET 2009 firedtv: avc: header file cleanup Remove unused constants and declarations. Move privately used constants into .c files. Wed Feb 11 21:21:04 CET 2009 firedtv: avc: remove bitfields from FCP frame types Don't use bitfields in struct types of on-the-wire data. Also move many privately used constants from avc.h to avc.c and remove some unused constants. Sun, 18 Jan 2009 16:30:00 +0100 (CET) firedtv: avc: fix offset in avc_tuner_get_ts The parentheses were wrong. It didn't matter though because this code only writes a 0 into an area which is already initialized to 0. Sun, 18 Jan 2009 16:30:00 +0100 (CET) firedtv: avc: reduce stack usage, remove two typedefs It is safe to share a memory buffer for command frame and response frame because the response data come in after the command frame was last used. Even less stack would be required if only the actual required frame size instead of the entire FCP register size was allocated. Also, rename the defined types AVCCmdFrm and AVCRspFrm to struct avc_command_frame and struct avc_response_frame. TODO: Remove the bitfields in these types. Sun, 18 Jan 2009 16:30:00 +0100 (CET) firedtv: cmp: move code to avc Sun, 18 Jan 2009 16:30:00 +0100 (CET) firedtv: iso: move code to firedtv-1394 Sun, 18 Jan 2009 16:30:00 +0100 (CET) firedtv: iso: remove unnecessary struct type definitions Sun, 18 Jan 2009 16:30:00 +0100 (CET) firedtv: iso: style changes and fixlets Add cleanup after failure in setup_iso_channel. Replace printk() by dv_err(). Decrease indentation level in rawiso_activity_cb(). Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
| | | * | firedtv: rename files, variables, functions from firesat to firedtvRambaldi2009-02-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Combination of the following changes: Sat, 17 Jan 2009 14:47:34 +0100 firedtv: rename variables and functions from firesat to firedtv Signed-off-by: Rambaldi <Rambaldi@xs4all.nl> Additional changes by Stefan Richter: Renamed struct firedtv *firedtv to struct firedtv *fdtv and firedtv_foo_bar() to fdtv_foo_bar() for brevity. Sat, 17 Jan 2009 13:07:44 +0100 firedtv: rename files from firesat to firedtv Signed-off-by: Rambaldi <Rambaldi@xs4all.nl> Additional changes by Stefan Richter: Name the directory "firewire" instead of "firedtv". Standardize on "-" instead of "_" in file names, because that's what drivers/firewire/ and drivers/media/dvb/dvb-usb/ use too. Build fix. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
| | | * | firedtv: Use DEFINE_SPINLOCKJulia Lawall2009-02-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | SPIN_LOCK_UNLOCKED is deprecated. The following makes the change suggested in Documentation/spinlocks.txt Signed-off-by: Julia Lawall <julia@diku.dk> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
| | | * | firedtv: fix registration - adapter number could only be zeroHenrik Kurelid2009-02-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There was a bug causing the initialization to fail if adapter number was greater than zero. The adapter was however registered which caused the driver to oops the second time initialization was tried. Signed-off-by: Henrik Kurelid <henrik@kurelid.se> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
| | | * | firedtv: use length_field() of PMT as lengthHenrik Kurelid2009-02-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Parsed and used the length_field() of the PMT message instead of using the length field of the message struct, which does not seem to be filled correctly by e.g. MythTV. Signed-off-by: Henrik Kurelid <henrik@kurelid.se> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
| | | * | firedtv: fix returned struct for ca_infoHenrik Kurelid2009-02-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The SystemId of the ca_info message was filled with garbage. It now returns what the card returns. Signed-off-by: Henrik Kurelid <henrik@kurelid.se> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
| | | * | firedtv: cleanups and minor fixesStefan Richter2009-02-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Combination of the following changes: Sun, 2 Nov 2008 13:45:00 +0100 (CET) firedtv: increase FCP frame length for DVB-S2 tune QSPK The last three bytes didn't go out to the wire. Effect of the fix not yet tested. Sun, 2 Nov 2008 13:45:00 +0100 (CET) firedtv: replace mdelay by msleep These functions can sleep (and in fact sleep for the duration of a whole FCP transaction). Hence msleep is more appropriate here. Sun, 2 Nov 2008 13:45:00 +0100 (CET) firedtv: trivial reorganization in avc_api Reduce nesting level by factoring code out of avc_tuner_dsd() into helper functions. Sun, 2 Nov 2008 13:45:00 +0100 (CET) firedtv: trivial cleanups in avc_api Use dev_err(), no CamelCase function names, adjust comment style, put #if 0 around unused code and add FIXME comments, standardize on lower-case hexadecimal constants, use ALIGN() for some frame length calculations, make a local function static... The code which writes FCP command frames and reads FCP response frames is not yet brought into canonical kernel coding style because this involves changes of typedefs (on-the-wire bitfields). Sun, 2 Nov 2008 13:45:00 +0100 (CET) firedtv: don't retry oPCR updates endlessly In the theoretical case that the target node wasn't handling the lock transactions as expected or there was continued interference by other initiating nodes, these functions wouldn't return for ages. Sun, 2 Nov 2008 13:45:00 +0100 (CET) firedtv: remove bitfield typedefs from cmp, fix for big endian CPUs Use macros/ inline functions/ standard byte order accessors to read and write oPCR register values (big endian bitfields, on-the-wire data). The new code may not be the ultimate optimum, but it doesn't occur in a hot path. This fixes the CMP code for big endian CPUs. So far I tested it only on a little endian CPU though. For now, include <asm/byteorder.h> instead of <linux/byteorder.h> because drivers/ieee1394/*.h also include the former. I will fix this in drivers/ieee1394 and firedtv later. Sun, 2 Nov 2008 13:45:00 +0100 (CET) firedtv: trivial cleanups in cmp Reduce nesting level by means of early exit and goto. Remove obsolete includes, use dev_err(), no CamelCase function names... Sun, 2 Nov 2008 13:45:00 +0100 (CET) firedtv: trivial cleanups in firesat-ci Whitespace, variable names, comment style... Also, use dvb_generic_open() and dvb_generic_release() directly as our hooks in struct file_operations because firedtv's wrappers merely called these generic functions. Sun, 2 Nov 2008 13:45:00 +0100 (CET) firedtv: remove CA debug code This looks like it is not necessary to have available for endusers who cannot patch kernels for bug reporting and tests of fixes. Sun, 2 Nov 2008 13:45:00 +0100 (CET) firedtv: remove AV/C debug code This looks like it is not necessary to have available for endusers who cannot patch kernels for bug reporting and tests of fixes. Sun, 2 Nov 2008 13:45:00 +0100 (CET) firedtv: remove various debug code Most of this was already commented out. And that which wasn't is not relevant in normal use. Mon, 29 Sep 2008 19:22:48 +0200 (CEST) firedtv: register input device as child of a FireWire device Instead of one virtual input device which exists for the whole lifetime of the driver and receives events from all connected FireDTVs, register one input device for each firedtv device. These input devices will show up as children of the respective firedtv devices in the sysfs hierarchy. However, the implementation falls short because of a bug in userspace: Udev's path_id script gets stuck with 100% CPU utilization, maybe because of an assumption about the maximum ieee1394 device hierarchy depth. To avoid this bug, we use the fw-host device instead of the proper unit_directory device as parent of the input device. There is hope that the port to the new firewire stack won't be inhibited by this userspace bug because there are no fw-host devices there. Mon, 29 Sep 2008 19:21:52 +0200 (CEST) firedtv: fix string comparison and a few sparse warnings Sparse found a bug: while ((kv_buf + kv_len - 1) == '\0') should have been while (kv_buf[kv_len - 1] == '\0') We fix it by a better implementation without a temporary copy. Also fix sparse warnings of 0 instead of NULL and signedness mismatches. Mon, 29 Sep 2008 19:21:20 +0200 (CEST) firedtv: remove unused struct members and redefine an int as a bool. Mon, 29 Sep 2008 19:20:36 +0200 (CEST) firedtv: fix initialization of dvb_frontend.ops There was a NULL pointer reference if no dvb_frontend_info was found. Also, don't directly assign struct typed values to struct typed variables. Instead write out assignments to individual strcut members. This reduces module size by about 1 kB. Mon, 29 Sep 2008 19:19:41 +0200 (CEST) firedtv: remove unused dual subunit code from initialization No FireDTVs with more than one subunit exists, hence simplify the initialization for the special case of one subunit. The driver was able to check for more than one subunit but was broken for more than two subunits. While we are at it, add several missing cleanups after failure, and include a few dynamically allocated structures diretly into struct firesat instead of allocating them separately. Mon, 29 Sep 2008 19:19:08 +0200 (CEST) firedtv: add vendor_id and version to driver match table Now that nodemgr was enhanced to match against the root directory's vendor ID if there isn't one in the unit directory, use this to prevent firedtv to be bound to wrong devices by accident. Also add the AV/C software version ID to the match flags for completeness; specifier ID and software only make sense as a pair. Mon, 29 Sep 2008 19:18:30 +0200 (CEST) firedtv: use hpsb_node_read(), _write(), _lock() because they are simpler and treat the node generation more correctly. While we are at it, clean up and simplify surrounding code. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
| | | * | ieee1394: remove superfluous assertionsStefan Richter2009-02-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | hpsb_read, hpsb_write, hpsb_lock are sleeping functions which nobody is in danger to use in atomic context. Besides, in_interrupt does not cover all types of atomic context. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
| | | * | ieee1394: inherit ud vendor_id from node vendor_idStefan Richter2009-02-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | While Module_Vendor_ID in the configuration ROM's root directory is mandatory, there often aren't vendor IDs in unit directories. This affects the new firedtv driver which is meant to be auto-loaded and matched only for vendor-specific devices. We now always copy ne->vendor_id into ud->vendor_id before we scan a unit directory (and fill in a possibly present vendor ID from there). This way, the root directory's vendor ID is used as fallback in the "uevent" environment for modprobe'ing per module alias when a node was plugged in, and in the driver match routine when protocol drivers are bound to unit directories. It will however not be used as sysfs attribute of a unit directory device. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>