- 14 Oct, 2008 40 commits
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Arjan van de Ven authored
When optimizing the kernel boot time, it's very valuable to visualize what is going on at which time. In addition, with the fastboot asynchronous initcall level, it's very valuable to see which initcall gets run where and when. This patch adds a script to turn a dmesg into a SVG graph (that can be shown with tools such as InkScape, Gimp or Firefox) and a small change to the initcall code to print the PID of the thread calling the initcall (so that the script can work out the parallelism). Signed-off-by:Arjan van de Ven <arjan@linux.intel.com>
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Lai Jiangshan authored
bit-field is not thread-safe nor smp-safe. struct marker_entry.rcu_pending is not protected by any lock in rcu-callback free_old_closure(). so we must turn it into a safe type. detail: I suppose rcu_pending and ptype are store in struct marker_entry.tmp1 free_old_closure() side: change ptype side: | load struct marker_entry.tmp1 --------------------------------|-------------------------------- | change ptype bit in tmp1 load struct marker_entry.tmp1 | change rcu_pending bit in tmp1 | store tmp1 | --------------------------------|-------------------------------- | store tmp1 now this result equals that free_old_closure() do not change rcu_pending bit, bug! This bug will cause redundant rcu_barrier_sched() called. not too harmful. ----- corresponding: free_old_closure() side: change ptype side: load struct marker_entry.tmp1 | --------------------------------|-------------------------------- | load struct marker_entry.tmp1 change rcu_pending bit in tmp1 | | change ptype bit in tmp1 | store tmp1 --------------------------------|-------------------------------- store tmp1 | now this result equals that change ptype side do not change ptype bit, bug! this bug cause marker_probe_cb() access to invalid memory. oops! see also: http://en.wikipedia.org/wiki/Bit_fieldSigned-off-by:Lai Jiangshan <laijs@cn.fujitsu.com> Acked-by:
Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Signed-off-by:
Ingo Molnar <mingo@elte.hu>
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Lai Jiangshan authored
when the second, third... probe is registered, its format is not checked, this patch fixes it. Signed-off-by:
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Mathieu Desnoyers authored
Turn marker synchronize unregister into a static inline. There is no reason to keep it as a macro over a static inline. Signed-off-by:
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Mathieu Desnoyers authored
Lai Jiangshan discovered a reentrancy issue with markers and fixed it by adding synchronize_sched() calls at each registration/unregistraiton. It works, but it removes the ability to do batch registration/unregistration and can cause registration of ~100 markers to take about 30 seconds on a loaded machine (synchronize_sched() is much slower on such workloads). This patch implements a version of the fix which won't slow down marker batch registration/unregistration. It also go back to the original non-synchronized reg/unreg. Signed-off-by:
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Mathieu Desnoyers authored
We need a marker_synchronize_unregister() before the end of exit() to make sure every probe callers have exited the non preemptible section and thus are not executing the probe code anymore. Signed-off-by:
Jeremy Kerr <jk@ozlabs.org> Signed-off-by:
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Mathieu Desnoyers authored
Document the need for a marker_synchronize_unregister() before the end of exit() to make sure every probe callers have exited the non preemptible section and thus are not executing the probe code anymore. Signed-off-by:
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Mathieu Desnoyers authored
Need a marker_synchronize_unregister() before the end of exit() to make sure every probe callers have exited the non preemptible section and thus are not executing the probe code anymore. Signed-off-by:
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Mathieu Desnoyers authored
Use the new rcu_read_lock_sched/unlock_sched() in marker code around the call site instead of preempt_disable/enable(). It helps reviewing the code more easily. Signed-off-by:
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Mathieu Desnoyers authored
Create marker_synchronize_unregister() which must be called before the end of exit() to make sure every probe callers have exited the non preemptible section and thus are not executing the probe code anymore. Signed-off-by:
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Mathieu Desnoyers authored
The tracepoints had the same problem markers did have wrt reentrancy. Apply a similar fix using a rcu_barrier after each tracepoint mutex lock. Signed-off-by:
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Mathieu Desnoyers authored
Make tracepoints use rcu sched. (cleanup) Signed-off-by:
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Lai Jiangshan authored
unregister bug: codes using makers are typically calling marker_probe_unregister() and then destroying the data that marker_probe_func needs(or unloading this module). This is bug when the corresponding marker_probe_func is still running(on other cpus), it is using the destroying/ed data. we should call synchronize_sched() after marker_update_probes(). reenter bug: marker_probe_register(), marker_probe_unregister() and marker_probe_unregister_private_data() are not reentrant safe functions. these 3 functions release markers_mutex and then require it again and do "entry->oldptr = old; ...", but entry->oldptr maybe is using now for these 3 functions may reenter when markers_mutex is released. we use synchronize_sched() instead of call_rcu_sched() to fix this bug. actually we can do: " if (entry->rcu_pending) rcu_barrier_sched(); " after require markers_mutex again. but synchronize_sched() is better and simpler. For these 3 functions are not critical path. Signed-off-by:
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Frédéric Weisbecker authored
With latest -tip I get this bug: [ 49.439988] in_atomic():0, irqs_disabled():1 [ 49.440118] INFO: lockdep is turned off. [ 49.440118] Pid: 2814, comm: modprobe Tainted: G W 2.6.27-rc7 #4 [ 49.440118] [<c01215e1>] __might_sleep+0xe1/0x120 [ 49.440118] [<c01148ea>] ftrace_modify_code+0x2a/0xd0 [ 49.440118] [<c01148a2>] ? ftrace_test_p6nop+0x0/0xa [ 49.440118] [<c016e80e>] __ftrace_update_code+0xfe/0x2f0 [ 49.440118] [<c01148a2>] ? ftrace_test_p6nop+0x0/0xa [ 49.440118] [<c016f190>] ftrace_convert_nops+0x50/0x80 [ 49.440118] [<c016f1d6>] ftrace_init_module+0x16/0x20 [ 49.440118] [<c015498b>] load_module+0x185b/0x1d30 [ 49.440118] [<c01767a0>] ? find_get_page+0x0/0xf0 [ 49.440118] [<c02463c0>] ? sprintf+0x0/0x30 [ 49.440118] [<c034e012>] ? mutex_lock_interruptible_nested+0x1f2/0x350 [ 49.440118] [<c0154eb3>] sys_init_module+0x53/0x1b0 [ 49.440118] [<c0352340>] ? do_page_fault+0x0/0x740 [ 49.440118] [<c0104012>] syscall_call+0x7/0xb [ 49.440118] ======================= It is because ftrace_modify_code() calls copy_to_user and copy_from_user. These functions have been inserted after guessing that there couldn't be any race condition but copy_[to/from]_user might sleep and __ftrace_update_code is called with local_irq_saved. These function have been inserted since this commit: d5e92e8978fd2574e415dc2792c5eb592978243d: "ftrace: x86 use copy from user function" Signed-off-by:
Frederic Weisbecker <fweisbec@gmail.com> Acked-by:
Steven Rostedt <rostedt@goodmis.org> Signed-off-by:
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Harvey Harrison authored
Could just as easily change the three casts to cast to the correct type...this patch changes the type of ftrace_nop instead. Supresses sparse warnings: arch/x86/kernel/ftrace.c:157:14: warning: incorrect type in assignment (different signedness) arch/x86/kernel/ftrace.c:157:14: expected long *static [toplevel] ftrace_nop arch/x86/kernel/ftrace.c:157:14: got unsigned long *<noident> arch/x86/kernel/ftrace.c:161:14: warning: incorrect type in assignment (different signedness) arch/x86/kernel/ftrace.c:161:14: expected long *static [toplevel] ftrace_nop arch/x86/kernel/ftrace.c:161:14: got unsigned long *<noident> arch/x86/kernel/ftrace.c:165:14: warning: incorrect type in assignment (different signedness) arch/x86/kernel/ftrace.c:165:14: expected long *static [toplevel] ftrace_nop arch/x86/kernel/ftrace.c:165:14: got unsigned long *<noident> Signed-off-by:
Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by:
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Steven Rostedt authored
With the recent updates to ftrace, there should not be any failures when modifying the code. If there is, then we need to warn about it. This patch has a cleaned up version of the code that I used to discover that the weak symbols were causing failures. Signed-off-by:
Steven Rostedt <srostedt@redhat.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
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Frédéric Weisbecker authored
Replace "none" tracer by the recently created "nop" tracer. Both are pretty similar except that nop accepts TRACE_PRINT or TRACE_SPECIAL entries. And as a consequence, changing the size of the ring buffer now requires that tracing has already been disabled. Signed-off-by:
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Frédéric Weisbecker authored
Now that the nop tracer is used as the default tracer by replacing the "none" tracer, tracing engine depends on it. Signed-off-by:
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Frédéric Weisbecker authored
If nop tracer is selected, some old entries from the previous tracer could still be enqueued. Tracing have to be reset. Signed-off-by:
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Steven Noonan authored
The functions are already 'extern' anyway, so there's no problem with linkage. Removing these ifdefs also helps find any potential compiler errors. Suggested by Andrew Morton. Signed-off-by:
Steven Noonan <steven@uplinklabs.net> Signed-off-by:
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Steven Noonan authored
When CONFIG_DYNAMIC_FTRACE isn't used, neither is mcount_addr. This patch eliminates that warning. Signed-off-by:
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Steven Noonan authored
A no-op tracer which can serve two purposes: 1. A template for development of a new tracer. 2. A convenient way to see ftrace_printk() calls without an irrelevant trace making the output messy. [ mingo@elte.hu: resolved conflicts ] Signed-off-by: -
Pekka Paalanen authored
Allow a user to inject a marker (TRACE_PRINT entry) into the trace ring buffer. The related file operations are derived from code by Frédéric Weisbecker <fweisbec@gmail.com>. Signed-off-by:
Pekka Paalanen <pq@iki.fi> Acked-by:
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Pekka Paalanen authored
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Pekka Paalanen authored
Also make trace_seq_print_cont() non-static, and add a newline if the seq buffer can't hold all data. Signed-off-by:
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Pekka Paalanen authored
Offer mmiotrace users a function to inject markers from inside the kernel. This depends on the trace_vprintk() patch. Signed-off-by:
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Pekka Paalanen authored
trace_vprintk() for easier implementation of tracer specific *_printk functions. Add check check for no_tracer, and implement __ftrace_printk() as a wrapper. Signed-off-by:
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Pekka Paalanen authored
Moves the mmiotrace specific functions from trace.c to trace_mmiotrace.c. Functions trace_wake_up(), tracing_get_trace_entry(), and tracing_generic_entry_update() are therefore made available outside trace.c. Signed-off-by:
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Pekka Paalanen authored
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Steven Rostedt authored
This must be brown paper bag week for Steven Rostedt! While working on ftrace for PPC, I discovered that the hash locking done when CONFIG_FTRACE_MCOUNT_RECORD is not set, is totally incorrect. With a cut and paste error, I had the hash lock macro to lock for both hash_lock _and_ hash_unlock! This bug did not affect x86 since this bug was introduced when CONFIG_FTRACE_MCOUNT_RECORD was added to x86. Signed-off-by:
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Steven Rostedt authored
ftrace_release is necessary for all uses of dynamic ftrace and not just the archs that have CONFIG_FTRACE_MCOUNT_RECORD defined. Signed-off-by:
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Ingo Molnar authored
make most of the tracers depend on DEBUG_KERNEL - that's their intended purpose. (most distributions have DEBUG_KERNEL enabled anyway so this is not a practical limitation - but it simplifies the tracing menu in the normal case) Signed-off-by: -
Peter Zijlstra authored
While profiling the smp behaviour of the scheduler it was needed to know to which cpu a task got woken. Signed-off-by:
Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by:
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Peter Zijlstra authored
Currently ftrace_printk only works with the ftrace tracer, switch it to an iter_ctrl setting so we can make us of them with other tracers too. [rostedt@redhat.com: tweak to the disable condition] Signed-off-by:
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Steven Rostedt authored
An item in the trace buffer that is bigger than one entry may be split up using the TRACE_CONT entry. This makes it a virtual single entry. The current code increments the iterator index even while traversing TRACE_CONT entries, making it look like the iterator is further than it actually is. This patch adds code to not increment the iterator index while skipping over TRACE_CONT entries. Signed-off-by:
Peter Zijlstra <peterz@infradead.org> Signed-off-by:
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Steven Rostedt authored
Peter Zijlstra provided me with a nice brown paper bag while letting me know that I was doing a logical AND and not a binary one, making a condition true more often than it should be. Luckily, a false true is handled by the calling function and no harm is done. But this needs to be fixed regardless. Signed-off-by:
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Michael Ellerman authored
Currently some of the ftrace output goes skewiff if you have more than 9 cpus, and some if you have more than 99. Twiddle with the headers and format strings to make up to 999 cpus display without causing spacing problems. Signed-off-by:
Michael Ellerman <michael@ellerman.id.au> Acked-by:
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Ingo Molnar authored
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Steven Rostedt authored
This patch adds indexes into the stack that the functions in the stack dump were found at. As an added bonus, I also added a diff to show which function is the most notorious consumer of the stack. The output now looks like this: # cat /debug/tracing/stack_trace Depth Size Location (48 entries) ----- ---- -------- 0) 2476 212 blk_recount_segments+0x39/0x59 1) 2264 12 bio_phys_segments+0x16/0x1d 2) 2252 20 blk_rq_bio_prep+0x23/0xaf 3) 2232 12 init_request_from_bio+0x74/0x77 4) 2220 56 __make_request+0x294/0x331 5) 2164 136 generic_make_request+0x34f/0x37d 6) 2028 56 submit_bio+0xe7/0xef 7) 1972 28 submit_bh+0xd1/0xf0 8) 1944 112 block_read_full_page+0x299/0x2a9 9) 1832 8 blkdev_readpage+0x14/0x16 10) 1824 28 read_cache_page_async+0x7e/0x109 11) 1796 16 read_cache_page+0x11/0x49 12) 1780 32 read_dev_sector+0x3c/0x72 13) 1748 48 read_lba+0x4d/0xaa 14) 1700 168 efi_partition+0x85/0x61b 15) 1532 72 rescan_partitions+0x10e/0x266 16) 1460 40 do_open+0x1c7/0x24e 17) 1420 292 __blkdev_get+0x79/0x84 18) 1128 12 blkdev_get+0x12/0x14 19) 1116 20 register_disk+0xd1/0x11e 20) 1096 28 add_disk+0x34/0x90 21) 1068 52 sd_probe+0x2b1/0x366 22) 1016 20 driver_probe_device+0xa5/0x120 23) 996 8 __device_attach+0xd/0xf 24) 988 32 bus_for_each_drv+0x3e/0x68 25) 956 24 device_attach+0x56/0x6c 26) 932 16 bus_attach_device+0x26/0x4d 27) 916 64 device_add+0x380/0x4b4 28) 852 28 scsi_sysfs_add_sdev+0xa1/0x1c9 29) 824 160 scsi_probe_and_add_lun+0x919/0xa2a 30) 664 36 __scsi_add_device+0x88/0xae 31) 628 44 ata_scsi_scan_host+0x9e/0x21c 32) 584 28 ata_host_register+0x1cb/0x1db 33) 556 24 ata_host_activate+0x98/0xb5 34) 532 192 ahci_init_one+0x9bd/0x9e9 35) 340 20 pci_device_probe+0x3e/0x5e 36) 320 20 driver_probe_device+0xa5/0x120 37) 300 20 __driver_attach+0x3f/0x5e 38) 280 36 bus_for_each_dev+0x40/0x62 39) 244 12 driver_attach+0x19/0x1b 40) 232 28 bus_add_driver+0x9c/0x1af 41) 204 28 driver_register+0x76/0xd2 42) 176 20 __pci_register_driver+0x44/0x71 43) 156 8 ahci_init+0x14/0x16 44) 148 100 _stext+0x42/0x122 45) 48 20 kernel_init+0x175/0x1dc 46) 28 28 kernel_thread_helper+0x7/0x10 The first column is simply an index starting from the inner most function and counting down to the outer most. The next column is the location that the function was found on the stack. The next column is the size of the stack for that function. Signed-off-by: -
Steven Rostedt authored
The warning messages about old objcopy and local functions spam the user quite drastically. Remove the warning until we can find a nicer way of tell the user to upgrade their objcopy. Signed-off-by:
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