linux/kernel/trace/trace.c, branch v2.6.39

Regression: partial revert "tracing: Remove lock_depth from event entry"

2011-05-06T20:20:59Z

This partially reverts commit e6e1e2593592a8f6f6380496655d8c6f67431266. That commit changed the structure layout of the trace structure, which in turn broke PowerTOP (1.9x generation) quite badly. I appreciate not wanting to expose the variable in question, and PowerTOP was not using it, so I've replaced the variable with just a padding field - that way if in the future a new field is needed it can just use this padding field. Signed-off-by: Arjan van de Ven Signed-off-by: Linus Torvalds

Fix common misspellings

2011-03-31T14:26:23Z

Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi

tracing: Fix irqoff selftest expanding max buffer

2011-03-10T15:34:58Z

If the kernel command line declares a tracer "ftrace=sometracer" and that tracer is either not defined or is enabled after irqsoff, then the irqs off selftest will fail with the following error: Testing tracer irqsoff: ------------[ cut here ]------------ WARNING: at /home/rostedt/work/autotest/nobackup/linux-test.git/kernel/trace/tra ce.c:713 update_max_tr_single+0xfa/0x11b() Hardware name: Modules linked in: Pid: 1, comm: swapper Not tainted 2.6.38-rc8-test #1 Call Trace: [] ? warn_slowpath_common+0x65/0x7a [] ? update_max_tr_single+0xfa/0x11b [] ? warn_slowpath_null+0xf/0x13 [] ? update_max_tr_single+0xfa/0x11b [] ? stop_critical_timing+0x154/0x204 [] ? trace_selftest_startup_irqsoff+0x5b/0xc1 [] ? trace_selftest_startup_irqsoff+0x5b/0xc1 [] ? trace_selftest_startup_irqsoff+0x5b/0xc1 [] ? time_hardirqs_on+0x25/0x28 [] ? trace_hardirqs_on_caller+0x18/0x12f [] ? trace_hardirqs_on+0xb/0xd [] ? trace_selftest_startup_irqsoff+0x5b/0xc1 [] ? register_tracer+0xf8/0x1a3 [] ? init_irqsoff_tracer+0xd/0x11 [] ? do_one_initcall+0x71/0x121 [] ? init_irqsoff_tracer+0x0/0x11 [] ? kernel_init+0x13a/0x1b6 [] ? kernel_init+0x0/0x1b6 [] ? kernel_thread_helper+0x6/0x10 ---[ end trace e93713a9d40cd06c ]--- .. no entries found ..FAILED! What happens is the "ftrace=..." will expand the ring buffer to its default size (from its minimum size) but it will not expand the max ring buffer (the ring buffer to store maximum latencies). When the irqsoff test runs, it will call the ring buffer swap routine that checks if the max ring buffer is the same size as the normal ring buffer, and will fail if it is not. This causes the test to fail. The solution is to expand the max ring buffer before running the self test if the max ring buffer is used by that tracer and the normal ring buffer is expanded. The max ring buffer should be shrunk again after the test is done to save space. Signed-off-by: Steven Rostedt

tracing: Remove lock_depth from event entry

2011-03-10T15:31:48Z

The lock_depth field in the event headers was added as a temporary data point for help in removing the BKL. Now that the BKL is pretty much been removed, we can remove this field. This in turn changes the header from 12 bytes to 8 bytes, removing the 4 byte buffer that gcc would insert if the first field in the data load was 8 bytes in size. Signed-off-by: Steven Rostedt

tracing: Add an 'overwrite' trace_option.

2011-03-09T18:52:27Z

Add an "overwrite" trace_option for ftrace to control whether the buffer should be overwritten on overflow or not. The default remains to overwrite old events when the buffer is full. This patch adds the option to instead discard newest events when the buffer is full. This is useful to get a snapshot of traces just after enabling traces. Dropping the current event is also a simpler code path. Signed-off-by: David Sharp LKML-Reference: <1291844807-15481-1-git-send-email-dhsharp@google.com> Signed-off-by: Steven Rostedt

tracing: Deprecate tracing_enabled for tracing_on

2011-02-08T22:14:58Z

tracing_enabled should not be used, it is heavy weight and does not do much in helping lower the overhead. tracing_on should be used instead. Warn users to use tracing_on when tracing_enabled is used as it will soon be removed from the tracing directory. Signed-off-by: Steven Rostedt

tracing: Fix preempt count leak

2011-01-08T04:20:02Z

While running my ftrace stress test, this showed up: BUG: sleeping function called from invalid context at mm/mmap.c:233 ... note: cat[3293] exited with preempt_count 1 The bug was introduced by commit 91e86e560d0b3ce4c5fc64fd2bbb99f856a30a4e ("tracing: Fix recursive user stack trace") Cc: Signed-off-by: Li Zefan LKML-Reference: <4D0089AC.1020802@cn.fujitsu.com> Signed-off-by: Steven Rostedt

Merge branch 'tip/perf/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace into perf/urgent

2010-12-16T10:21:24Z

tracing: Fix panic when lseek() called on "trace" opened for writing

2010-11-30T17:18:17Z

The file_ops struct for the "trace" special file defined llseek as seq_lseek(). However, if the file was opened for writing only, seq_open() was not called, and the seek would dereference a null pointer, file->private_data. This patch introduces a new wrapper for seq_lseek() which checks if the file descriptor is opened for reading first. If not, it does nothing. Cc: Signed-off-by: Slava Pestov LKML-Reference: <1290640396-24179-1-git-send-email-slavapestov@google.com> Signed-off-by: Steven Rostedt

Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

2010-11-26T22:28:17Z

* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: perf symbols: Remove incorrect open-coded container_of() perf record: Handle restrictive permissions in /proc/{kallsyms,modules} x86/kprobes: Prevent kprobes to probe on save_args() irq_work: Drop cmpxchg() result perf: Fix owner-list vs exit x86, hw_nmi: Move backtrace_mask declaration under ARCH_HAS_NMI_WATCHDOG tracing: Fix recursive user stack trace perf,hw_breakpoint: Initialize hardware api earlier x86: Ignore trap bits on single step exceptions tracing: Force arch_local_irq_* notrace for paravirt tracing: Fix module use of trace_bprintk()