user/sven/linux.git/kernel/trace/trace.c, branch v3.14.49

move d_rcu from overlapping d_child to overlapping d_alias

2015-04-29T08:31:54Z

commit 946e51f2bf37f1656916eb75bd0742ba33983c28 upstream. move d_rcu from overlapping d_child to overlapping d_alias Signed-off-by: Al Viro Cc: Ben Hutchings [hujianyang: Backported to 3.14 refer to the work of Ben Hutchings in 3.2: - Apply name changes in all the different places we use d_alias and d_child - Move the WARN_ON() in __d_free() to d_free() as we don't have dentry_free()] Signed-off-by: hujianyang Signed-off-by: Greg Kroah-Hartman

tracing: Fix unmapping loop in tracing_mark_write

2015-03-06T22:43:28Z

commit 7215853e985a4bef1a6c14e00e89dfec84f1e457 upstream. Commit 6edb2a8a385f0cdef51dae37ff23e74d76d8a6ce introduced an array map_pages that contains the addresses returned by kmap_atomic. However, when unmapping those pages, map_pages[0] is unmapped before map_pages[1], breaking the nesting requirement as specified in the documentation for kmap_atomic/kunmap_atomic. This was caught by the highmem debug code present in kunmap_atomic. Fix the loop to do the unmapping properly. Link: http://lkml.kernel.org/r/1418871056-6614-1-git-send-email-markivx@codeaurora.org Reviewed-by: Stephen Boyd Reported-by: Lime Yang Signed-off-by: Vikram Mulukutla Signed-off-by: Steven Rostedt Signed-off-by: Greg Kroah-Hartman

tracing: Fix wraparound problems in "uptime" trace clock

2014-07-31T19:52:55Z

commit 58d4e21e50ff3cc57910a8abc20d7e14375d2f61 upstream. The "uptime" trace clock added in: commit 8aacf017b065a805d27467843490c976835eb4a5 tracing: Add "uptime" trace clock that uses jiffies has wraparound problems when the system has been up more than 1 hour 11 minutes and 34 seconds. It converts jiffies to nanoseconds using: (u64)jiffies_to_usecs(jiffy) * 1000ULL but since jiffies_to_usecs() only returns a 32-bit value, it truncates at 2^32 microseconds. An additional problem on 32-bit systems is that the argument is "unsigned long", so fixing the return value only helps until 2^32 jiffies (49.7 days on a HZ=1000 system). Avoid these problems by using jiffies_64 as our basis, and not converting to nanoseconds (we do convert to clock_t because user facing API must not be dependent on internal kernel HZ values). Link: http://lkml.kernel.org/p/99d63c5bfe9b320a3b428d773825a37095bf6a51.1405708254.git.tony.luck@intel.com Fixes: 8aacf017b065 "tracing: Add "uptime" trace clock that uses jiffies" Signed-off-by: Tony Luck Signed-off-by: Steven Rostedt Signed-off-by: Greg Kroah-Hartman

tracing: Add TRACE_ITER_PRINTK flag check in __trace_puts/__trace_bputs

2014-07-28T15:05:57Z

commit f0160a5a2912267c02cfe692eac955c360de5fdf upstream. The TRACE_ITER_PRINTK check in __trace_puts/__trace_bputs is missing, so add it, to be consistent with __trace_printk/__trace_bprintk. Those functions are all called by the same function: trace_printk(). Link: http://lkml.kernel.org/p/51E7A7D6.8090900@huawei.com Signed-off-by: zhangwei(Jovi) Signed-off-by: Steven Rostedt Signed-off-by: Greg Kroah-Hartman

tracing: Add ftrace_trace_stack into __trace_puts/__trace_bputs

2014-07-28T15:05:57Z

commit 8abfb8727f4a724d31f9ccfd8013fbd16d539445 upstream. Currently trace option stacktrace is not applicable for trace_printk with constant string argument, the reason is in __trace_puts/__trace_bputs ftrace_trace_stack is missing. In contrast, when using trace_printk with non constant string argument(will call into __trace_printk/__trace_bprintk), then trace option stacktrace is workable, this inconstant result will confuses users a lot. Link: http://lkml.kernel.org/p/51E7A7C9.9040401@huawei.com Signed-off-by: zhangwei(Jovi) Signed-off-by: Steven Rostedt Signed-off-by: Greg Kroah-Hartman

ring-buffer: Check if buffer exists before polling

2014-07-17T23:21:06Z

commit 8b8b36834d0fff67fc8668093f4312dd04dcf21d upstream. The per_cpu buffers are created one per possible CPU. But these do not mean that those CPUs are online, nor do they even exist. With the addition of the ring buffer polling, it assumes that the caller polls on an existing buffer. But this is not the case if the user reads trace_pipe from a CPU that does not exist, and this causes the kernel to crash. Simple fix is to check the cpu against buffer bitmask against to see if the buffer was allocated or not and return -ENODEV if it is not. More updates were done to pass the -ENODEV back up to userspace. Link: http://lkml.kernel.org/r/5393DB61.6060707@oracle.com Reported-by: Sasha Levin Signed-off-by: Steven Rostedt Signed-off-by: Greg Kroah-Hartman

tracing: Remove ftrace_stop/start() from reading the trace file

2014-07-09T18:18:28Z

commit 099ed151675cd1d2dbeae1dac697975f6a68716d upstream. Disabling reading and writing to the trace file should not be able to disable all function tracing callbacks. There's other users today (like kprobes and perf). Reading a trace file should not stop those from happening. Reviewed-by: Masami Hiramatsu Signed-off-by: Steven Rostedt Signed-off-by: Greg Kroah-Hartman

tracing: Try again for saved cmdline if failed due to locking

2014-07-07T01:57:29Z

commit 379cfdac37923653c9d4242d10052378b7563005 upstream. In order to prevent the saved cmdline cache from being filled when tracing is not active, the comms are only recorded after a trace event is recorded. The problem is, a comm can fail to be recorded if the trace_cmdline_lock is held. That lock is taken via a trylock to allow it to happen from any context (including NMI). If the lock fails to be taken, the comm is skipped. No big deal, as we will try again later. But! Because of the code that was added to only record after an event, we may not try again later as the recording is made as a oneshot per event per CPU. Only disable the recording of the comm if the comm is actually recorded. Fixes: 7ffbd48d5cab "tracing: Cache comms only after an event occurred" Signed-off-by: Steven Rostedt Signed-off-by: Greg Kroah-Hartman

tracing: Fix traceon trigger condition to actually turn tracing on

2014-03-26T03:39:41Z

While working on my tutorial for 2014 Linux Collaboration Summit I found that the traceon trigger did not work when conditions were used. The other triggers worked fine though. Looking into it, it is because of the way the triggers use the ring buffer to store the fields it will use for the condition. But if tracing is off, nothing is stored in the buffer, and the tracepoint exits before calling the trigger to test the condition. This is fine for all the triggers that only work when tracing is on, but for traceon trigger that is to work when tracing is off, nothing happens. The fix is simple, just use a temp ring buffer to record the event if tracing is off and the event has a trace event conditional trigger enabled. The rest of the tracepoint code will work just fine, but the tracepoint wont be recorded in the other buffers. Cc: Tom Zanussi Signed-off-by: Steven Rostedt

tracing: Check if tracing is enabled in trace_puts()

2014-01-23T17:27:59Z

If trace_puts() is used very early in boot up, it can crash the machine if it is called before the ring buffer is allocated. If a trace_printk() is used with no arguments, then it will be converted into a trace_puts() and suffer the same fate. Cc: stable@vger.kernel.org # 3.10+ Fixes: 09ae72348ecc "tracing: Add trace_puts() for even faster trace_printk() tracing" Signed-off-by: Steven Rostedt