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* ftrace: Reuse the output of the function tracer for func_repeatsSteven Rostedt (VMware)2021-04-151-10/+13
| | | | | | | | | | | | The func_repeats event shows the output of the function tracer followed by a count of the number of repeats the previous function had made, as well as the timestamp of the last function that was repeated. The printing of the function should be the same as is for the function it is displaying. Reuse the code in trace_fn_trace() by making a helper function print_fn_trace() and use it for trace_func_repeats_print(). Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* tracing: Define new ftrace event "func_repeats"Yordan Karadzhov (VMware)2021-04-151-0/+48
| | | | | | | | | | | | | | | | | The event aims to consolidate the function tracing record in the cases when a single function is called number of times consecutively. while (cond) do_func(); This may happen in various scenarios (busy waiting for example). The new ftrace event can be used to show repeated function events with a single event and save space on the ring buffer Link: https://lkml.kernel.org/r/20210415181854.147448-3-y.karadz@gmail.com Signed-off-by: Yordan Karadzhov (VMware) <y.karadz@gmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* tracing: Define static void trace_print_time()Yordan Karadzhov (VMware)2021-04-151-9/+17
| | | | | | | | | | | | | | The part of the code that prints the time of the trace record in "int trace_print_context()" gets extracted in a static function. This is done as a preparation for a following patch, in which we will define a new ftrace event called "func_repeats". The new static method, defined here, will be used by this new event to print the time of the last repeat of a function that is consecutively called number of times. Link: https://lkml.kernel.org/r/20210415181854.147448-2-y.karadz@gmail.com Signed-off-by: Yordan Karadzhov (VMware) <y.karadz@gmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* tracing: Add a verifier to check string pointers for trace eventsSteven Rostedt (VMware)2021-03-181-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | It is a common mistake for someone writing a trace event to save a pointer to a string in the TP_fast_assign() and then display that string pointer in the TP_printk() with %s. The problem is that those two events may happen a long time apart, where the source of the string may no longer exist. The proper way to handle displaying any string that is not guaranteed to be in the kernel core rodata section, is to copy it into the ring buffer via the __string(), __assign_str() and __get_str() helper macros. Add a check at run time while displaying the TP_printk() of events to make sure that every %s referenced is safe to dereference, and if it is not, trigger a warning and only show the address of the pointer, and the dereferenced string if it can be safely retrieved with a strncpy_from_kernel_nofault() call. In order to not have to copy the parsing of vsnprintf() formats, or even exporting its code, the verifier relies on vsnprintf() being able to modify the va_list that is passed to it, and it remains modified after it is called. This is the case for some architectures like x86_64, but other architectures like x86_32 pass the va_list to vsnprintf() as a value not a reference, and the verifier can not use it to parse the non string arguments. Thus, at boot up, it is checked if vsnprintf() modifies the passed in va_list or not, and a static branch will disable the verifier if it's not compatible. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* tracing: Show real address for trace event argumentsMasami Hiramatsu2021-02-111-1/+11
| | | | | | | | | | | | | | | | | | | | | | To help debugging kernel, show real address for trace event arguments in tracefs/trace{,pipe} instead of hashed pointer value. Since ftrace human-readable format uses vsprintf(), all %p are translated to hash values instead of pointer address. However, when debugging the kernel, raw address value gives a hint when comparing with the memory mapping in the kernel. (Those are sometimes used with crash log, which is not hashed too) So converting %p with %px when calling trace_seq_printf(). Moreover, this is not improving the security because the tracefs can be used only by root user and the raw address values are readable from tracefs/percpu/cpu*/trace_pipe_raw file. Link: https://lkml.kernel.org/r/160277370703.29307.5134475491761971203.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* ftrace: Add recording of functions that caused recursionSteven Rostedt (VMware)2020-11-061-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds CONFIG_FTRACE_RECORD_RECURSION that will record to a file "recursed_functions" all the functions that caused recursion while a callback to the function tracer was running. Link: https://lkml.kernel.org/r/20201106023548.102375687@goodmis.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Guo Ren <guoren@kernel.org> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: Helge Deller <deller@gmx.de> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Borislav Petkov <bp@alien8.de> Cc: x86@kernel.org Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Anton Vorontsov <anton@enomsg.org> Cc: Colin Cross <ccross@android.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Jiri Kosina <jikos@kernel.org> Cc: Miroslav Benes <mbenes@suse.cz> Cc: Petr Mladek <pmladek@suse.com> Cc: Joe Lawrence <joe.lawrence@redhat.com> Cc: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> Cc: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-csky@vger.kernel.org Cc: linux-parisc@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-s390@vger.kernel.org Cc: live-patching@vger.kernel.org Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* tracing: Make the space reserved for the pid widerSebastian Andrzej Siewior2020-09-181-6/+6
| | | | | | | | | | | | | | | | | | | | | For 64bit CONFIG_BASE_SMALL=0 systems PID_MAX_LIMIT is set by default to 4194304. During boot the kernel sets a new value based on number of CPUs but no lower than 32768. It is 1024 per CPU so with 128 CPUs the default becomes 131072 which needs six digits. This value can be increased during run time but must not exceed the initial upper limit. Systemd sometime after v241 sets it to the upper limit during boot. The result is that when the pid exceeds five digits, the trace output is a little hard to read because it is no longer properly padded (same like on big iron with 98+ CPUs). Increase the pid padding to seven digits. Link: https://lkml.kernel.org/r/20200904082331.dcdkrr3bkn3e4qlg@linutronix.de Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* tracing: Save one trace_event->type by using __TRACE_LAST_TYPEWei Yang2020-07-091-2/+2
| | | | | | | | | | | | Static defined trace_event->type stops at (__TRACE_LAST_TYPE - 1) and dynamic trace_event->type starts from (__TRACE_LAST_TYPE + 1). To save one trace_event->type index, let's use __TRACE_LAST_TYPE. Link: https://lkml.kernel.org/r/20200703020612.12930-3-richard.weiyang@linux.alibaba.com Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* tracing: Simplify defining of the next event idWei Yang2020-07-091-6/+6
| | | | | | | | | | | The value to be used and compared in trace_search_list() is "last + 1". Let's just define next to be "last + 1" instead of doing the addition each time. Link: https://lkml.kernel.org/r/20200703020612.12930-2-richard.weiyang@linux.alibaba.com Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* mmap locking API: use coccinelle to convert mmap_sem rwsem call sitesMichel Lespinasse2020-06-091-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This change converts the existing mmap_sem rwsem calls to use the new mmap locking API instead. The change is generated using coccinelle with the following rule: // spatch --sp-file mmap_lock_api.cocci --in-place --include-headers --dir . @@ expression mm; @@ ( -init_rwsem +mmap_init_lock | -down_write +mmap_write_lock | -down_write_killable +mmap_write_lock_killable | -down_write_trylock +mmap_write_trylock | -up_write +mmap_write_unlock | -downgrade_write +mmap_write_downgrade | -down_read +mmap_read_lock | -down_read_killable +mmap_read_lock_killable | -down_read_trylock +mmap_read_trylock | -up_read +mmap_read_unlock ) -(&mm->mmap_sem) +(mm) Signed-off-by: Michel Lespinasse <walken@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Cc: Davidlohr Bueso <dbueso@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jerome Glisse <jglisse@redhat.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ying Han <yinghan@google.com> Link: http://lkml.kernel.org/r/20200520052908.204642-5-walken@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* tracing: Save off entry when peeking at next entrySteven Rostedt (VMware)2020-03-191-9/+6
| | | | | | | | | | | | | | | | | | | In order to have the iterator read the buffer even when it's still updating, it requires that the ring buffer iterator saves each event in a separate location outside the ring buffer such that its use is immutable. There's one use case that saves off the event returned from the ring buffer interator and calls it again to look at the next event, before going back to use the first event. As the ring buffer iterator will only have a single copy, this use case will no longer be supported. Instead, have the one use case create its own buffer to store the first event when looking at the next event. This way, when looking at the first event again, it wont be corrupted by the second read. Link: http://lkml.kernel.org/r/20200317213415.722539921@goodmis.org Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* tracing: Have hwlat ts be first instance and record count of instancesSteven Rostedt (VMware)2020-03-031-2/+2
| | | | | | | | | | | | The hwlat tracer runs a loop of width time during a given window. It then reports the max latency over a given threshold and records a timestamp. But this timestamp is the time after the width has finished, and not the time it actually triggered. Record the actual time when the latency was greater than the threshold as well as the number of times it was greater in a given width per window. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* tracing: Rename trace_buffer to array_bufferSteven Rostedt (VMware)2020-01-131-1/+1
| | | | | | | | | | | | | As we are working to remove the generic "ring_buffer" name that is used by both tracing and perf, the ring_buffer name for tracing will be renamed to trace_buffer, and perf's ring buffer will be renamed to perf_buffer. As there already exists a trace_buffer that is used by the trace_arrays, it needs to be first renamed to array_buffer. Link: https://lore.kernel.org/r/20191213153553.GE20583@krava Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* tracing: Use seq_buf_hex_dump() to dump buffersPiotr Maziarz2019-11-141-0/+15
| | | | | | | | | | | | | | Without this, buffers can be printed with __print_array macro that has no formatting options and can be hard to read. The other way is to mimic formatting capability with multiple calls of trace event with one call per row which gives performance impact and different timestamp in each row. Link: http://lkml.kernel.org/r/1573130738-29390-2-git-send-email-piotrx.maziarz@linux.intel.com Signed-off-by: Piotr Maziarz <piotrx.maziarz@linux.intel.com> Signed-off-by: Cezary Rojewski <cezary.rojewski@intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* tracing: Be more clever when dumping hex in __print_hex()Andy Shevchenko2019-09-171-3/+3
| | | | | | | | | | Hex dump as many as 16 bytes at once in trace_print_hex_seq() instead of byte-by-byte approach. Link: http://lkml.kernel.org/r/20190806151543.86061-1-andriy.shevchenko@linux.intel.com Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* Merge tag 'trace-v5.3-2' of ↵Linus Torvalds2019-07-191-8/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fix from Steven Rostedt: "Eiichi Tsukata found a small bug from the fixup of the stack code Removing ULONG_MAX as the marker for the user stack trace end, made the tracing code not know where the end is. The end is now marked with a zero (NULL) pointer. Eiichi fixed this in the tracing code" * tag 'trace-v5.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing: Fix user stack trace "??" output
| * tracing: Fix user stack trace "??" outputEiichi Tsukata2019-07-191-8/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit c5c27a0a5838 ("x86/stacktrace: Remove the pointless ULONG_MAX marker") removes ULONG_MAX marker from user stack trace entries but trace_user_stack_print() still uses the marker and it outputs unnecessary "??". For example: less-1911 [001] d..2 34.758944: <user stack trace> => <00007f16f2295910> => ?? => ?? => ?? => ?? => ?? => ?? => ?? The user stack trace code zeroes the storage before saving the stack, so if the trace is shorter than the maximum number of entries it can terminate the print loop if a zero entry is detected. Link: http://lkml.kernel.org/r/20190630085438.25545-1-devel@etsukata.com Cc: stable@vger.kernel.org Fixes: 4285f2fcef80 ("tracing: Remove the ULONG_MAX stack trace hackery") Signed-off-by: Eiichi Tsukata <devel@etsukata.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* | tracing: Fix out-of-range read in trace_stack_print()Eiichi Tsukata2019-06-141-1/+1
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Puts range check before dereferencing the pointer. Reproducer: # echo stacktrace > trace_options # echo 1 > events/enable # cat trace > /dev/null KASAN report: ================================================================== BUG: KASAN: use-after-free in trace_stack_print+0x26b/0x2c0 Read of size 8 at addr ffff888069d20000 by task cat/1953 CPU: 0 PID: 1953 Comm: cat Not tainted 5.2.0-rc3+ #5 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-2.fc30 04/01/2014 Call Trace: dump_stack+0x8a/0xce print_address_description+0x60/0x224 ? trace_stack_print+0x26b/0x2c0 ? trace_stack_print+0x26b/0x2c0 __kasan_report.cold+0x1a/0x3e ? trace_stack_print+0x26b/0x2c0 kasan_report+0xe/0x20 trace_stack_print+0x26b/0x2c0 print_trace_line+0x6ea/0x14d0 ? tracing_buffers_read+0x700/0x700 ? trace_find_next_entry_inc+0x158/0x1d0 s_show+0xea/0x310 seq_read+0xaa7/0x10e0 ? seq_escape+0x230/0x230 __vfs_read+0x7c/0x100 vfs_read+0x16c/0x3a0 ksys_read+0x121/0x240 ? kernel_write+0x110/0x110 ? perf_trace_sys_enter+0x8a0/0x8a0 ? syscall_slow_exit_work+0xa9/0x410 do_syscall_64+0xb7/0x390 ? prepare_exit_to_usermode+0x165/0x200 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f867681f910 Code: b6 fe ff ff 48 8d 3d 0f be 08 00 48 83 ec 08 e8 06 db 01 00 66 0f 1f 44 00 00 83 3d f9 2d 2c 00 00 75 10 b8 00 00 00 00 04 RSP: 002b:00007ffdabf23488 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 0000000000020000 RCX: 00007f867681f910 RDX: 0000000000020000 RSI: 00007f8676cde000 RDI: 0000000000000003 RBP: 00007f8676cde000 R08: ffffffffffffffff R09: 0000000000000000 R10: 0000000000000871 R11: 0000000000000246 R12: 00007f8676cde000 R13: 0000000000000003 R14: 0000000000020000 R15: 0000000000000ec0 Allocated by task 1214: save_stack+0x1b/0x80 __kasan_kmalloc.constprop.0+0xc2/0xd0 kmem_cache_alloc+0xaf/0x1a0 getname_flags+0xd2/0x5b0 do_sys_open+0x277/0x5a0 do_syscall_64+0xb7/0x390 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 1214: save_stack+0x1b/0x80 __kasan_slab_free+0x12c/0x170 kmem_cache_free+0x8a/0x1c0 putname+0xe1/0x120 do_sys_open+0x2c5/0x5a0 do_syscall_64+0xb7/0x390 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The buggy address belongs to the object at ffff888069d20000 which belongs to the cache names_cache of size 4096 The buggy address is located 0 bytes inside of 4096-byte region [ffff888069d20000, ffff888069d21000) The buggy address belongs to the page: page:ffffea0001a74800 refcount:1 mapcount:0 mapping:ffff88806ccd1380 index:0x0 compound_mapcount: 0 flags: 0x100000000010200(slab|head) raw: 0100000000010200 dead000000000100 dead000000000200 ffff88806ccd1380 raw: 0000000000000000 0000000000070007 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888069d1ff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888069d1ff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888069d20000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888069d20080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888069d20100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== Link: http://lkml.kernel.org/r/20190610040016.5598-1-devel@etsukata.com Fixes: 4285f2fcef80 ("tracing: Remove the ULONG_MAX stack trace hackery") Signed-off-by: Eiichi Tsukata <devel@etsukata.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* tracing: Simplify printf'ing in seq_print_symRasmus Villemoes2018-12-221-4/+3
| | | | | | | | | | | | | | | | trace_seq_printf(..., "%s", ...) can be done with trace_seq_puts() instead, avoiding printf overhead. In the second instance, the string we're copying was just created from an snprintf() to a stack buffer, so we might as well do that printf directly. This naturally leads to moving the declaration of the str buffer inside the CONFIG_KALLSYMS guard, which in turn will make gcc inline the function for !CONFIG_KALLSYMS (it only has a single caller, but the huge stack frame seems to make gcc not inline it for CONFIG_KALLSYMS). Link: http://lkml.kernel.org/r/20181029223542.26175-4-linux@rasmusvillemoes.dk Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* tracing: Avoid -Wformat-nonliteral warningRasmus Villemoes2018-12-221-5/+4
| | | | | | | | | | | | | | | | | | Building with -Wformat-nonliteral, gcc complains kernel/trace/trace_output.c: In function ‘seq_print_sym’: kernel/trace/trace_output.c:356:3: warning: format not a string literal, argument types not checked [-Wformat-nonliteral] trace_seq_printf(s, fmt, name); But seq_print_sym only has a single caller which passes "%s" as fmt, so we might as well just use that directly. That also paves the way for further cleanups that will actually make that format string go away entirely. Link: http://lkml.kernel.org/r/20181029223542.26175-3-linux@rasmusvillemoes.dk Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* tracing: Merge seq_print_sym_short() and seq_print_sym_offset()Rasmus Villemoes2018-12-221-27/+7
| | | | | | | | | | These two functions are nearly identical, so we can avoid some code duplication by moving the conditional into a common implementation. Link: http://lkml.kernel.org/r/20181029223542.26175-2-linux@rasmusvillemoes.dk Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* tracing: Add SPDX License format tags to tracing filesSteven Rostedt (VMware)2018-08-161-0/+1
| | | | | | Add the SPDX License header to ease license compliance management. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* tracing: Reorder display of TGID to be after PIDJoel Fernandes (Google)2018-07-121-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently ftrace displays data in trace output like so: _-----=> irqs-off / _----=> need-resched | / _---=> hardirq/softirq || / _--=> preempt-depth ||| / delay TASK-PID CPU TGID |||| TIMESTAMP FUNCTION | | | | |||| | | bash-1091 [000] ( 1091) d..2 28.313544: sched_switch: However Android's trace visualization tools expect a slightly different format due to an out-of-tree patch patch that was been carried for a decade, notice that the TGID and CPU fields are reversed: _-----=> irqs-off / _----=> need-resched | / _---=> hardirq/softirq || / _--=> preempt-depth ||| / delay TASK-PID TGID CPU |||| TIMESTAMP FUNCTION | | | | |||| | | bash-1091 ( 1091) [002] d..2 64.965177: sched_switch: From kernel v4.13 onwards, during which TGID was introduced, tracing with systrace on all Android kernels will break (most Android kernels have been on 4.9 with Android patches, so this issues hasn't been seen yet). From v4.13 onwards things will break. The chrome browser's tracing tools also embed the systrace viewer which uses the legacy TGID format and updates to that are known to be difficult to make. Considering this, I suggest we make this change to the upstream kernel and backport it to all Android kernels. I believe this feature is merged recently enough into the upstream kernel that it shouldn't be a problem. Also logically, IMO it makes more sense to group the TGID with the TASK-PID and the CPU after these. Link: http://lkml.kernel.org/r/20180626000822.113931-1-joel@joelfernandes.org Cc: jreck@google.com Cc: tkjos@google.com Cc: stable@vger.kernel.org Fixes: 441dae8f2f29 ("tracing: Add support for display of tgid in trace output") Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* sched/debug: Rename task-state printing helpersPeter Zijlstra2017-10-101-6/+6
| | | | | | | | | | | | | | | | | | Steve requested better names for the new task-state helper functions. So introduce the concept of task-state index for the printing and rename __get_task_state() to task_state_index() and __task_state_to_char() to task_index_to_char(). Requested-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20170929115016.pzlqc7ss3ccystyg@hirez.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
* sched/tracing: Use common task-state helpersPeter Zijlstra2017-09-291-15/+6
| | | | | | | | | | | Remove yet another task-state char instance. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* tracing: Add support for display of tgid in trace outputJoel Fernandes2017-06-271-0/+9
| | | | | | | | | | | | | Earlier patches introduced ability to record the tgid using the 'record-tgid' option. Here we read the tgid and output it if the option is enabled. Link: http://lkml.kernel.org/r/20170626053844.5746-3-joelaf@google.com Cc: kernel-team@android.com Cc: Ingo Molnar <mingo@redhat.com> Tested-by: Michael Sartain <mikesart@gmail.com> Signed-off-by: Joel Fernandes <joelaf@google.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* tracing: Show address when function names are not foundSteven Rostedt (VMware)2017-06-221-4/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, when a function is not found in kallsyms, instead of simply showing the function address, it shows nothing at all: # echo ':mod:kvm_intel' > /sys/kernel/tracing/set_ftrace_filter # echo function > /sys/kernel/tracing/set_ftrace_filter # qemu -enable-kvm /home/my-qemu-image <Ctrl-C> # rmmod kvm_intel # cat /sys/kernel/tracing/trace qemu-system-x86-2408 [001] d..2 135.013238: <-kvm_arch_hardware_enable qemu-system-x86-2408 [001] .... 135.014574: <-kvm_arch_vm_ioctl qemu-system-x86-2408 [001] .... 135.015420: <-kvm_vm_ioctl_check_extension qemu-system-x86-2408 [001] .... 135.045411: <-__do_cpuid_ent qemu-system-x86-2408 [001] .... 135.045412: <-__do_cpuid_ent qemu-system-x86-2408 [001] .... 135.045412: <-__do_cpuid_ent qemu-system-x86-2408 [001] .... 135.045412: <-__do_cpuid_ent qemu-system-x86-2408 [001] ...1 135.045413: <-__do_cpuid_ent qemu-system-x86-2408 [001] .... 135.045413: <-__do_cpuid_ent When it should show: qemu-system-x86-2408 [001] d..2 135.013238: 0xffffffffa02a39f0 <-kvm_arch_hardware_enable qemu-system-x86-2408 [001] .... 135.014574: 0xffffffffa02a2ba0 <-kvm_arch_vm_ioctl qemu-system-x86-2408 [001] .... 135.015420: 0xffffffffa029e4e0 <-kvm_vm_ioctl_check_extension qemu-system-x86-2408 [001] .... 135.045411: 0xffffffffa02a1380 <-__do_cpuid_ent qemu-system-x86-2408 [001] .... 135.045412: 0xffffffffa029e160 <-__do_cpuid_ent qemu-system-x86-2408 [001] .... 135.045412: 0xffffffffa029e180 <-__do_cpuid_ent qemu-system-x86-2408 [001] .... 135.045412: 0xffffffffa029e520 <-__do_cpuid_ent qemu-system-x86-2408 [001] ...1 135.045413: 0xffffffffa02a13b0 <-__do_cpuid_ent qemu-system-x86-2408 [001] .... 135.045413: 0xffffffffa02a1380 <-__do_cpuid_ent instead. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* trace: make trace_hwlat timestamp y2038 safeDeepa Dinamani2017-05-081-5/+4
| | | | | | | | | | | | | | | | struct timespec is not y2038 safe on 32 bit machines and needs to be replaced by struct timespec64 in order to represent times beyond year 2038 on such machines. Fix all the timestamp representation in struct trace_hwlat and all the corresponding implementations. Link: http://lkml.kernel.org/r/1491613030-11599-3-git-send-email-deepa.kernel@gmail.com Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar2017-03-021-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | <linux/sched/mm.h> We are going to split <linux/sched/mm.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/mm.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. The APIs that are going to be moved first are: mm_alloc() __mmdrop() mmdrop() mmdrop_async_fn() mmdrop_async() mmget_not_zero() mmput() mmput_async() get_task_mm() mm_access() mm_release() Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar2017-03-021-0/+1
| | | | | | | | | | | | | | | | | | | | <linux/sched/clock.h> We are going to split <linux/sched/clock.h> out of <linux/sched.h>, which will have to be picked up from other headers and .c files. Create a trivial placeholder <linux/sched/clock.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* tracing: add __print_flags_u64()Ross Zwisler2017-02-221-0/+38
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Patch series "DAX tracepoints, mm argument simplification", v4. This contains both my DAX tracepoint code and Dave Jiang's MM argument simplifications. Dave's code was written with my tracepoint code as a baseline, so it seemed simplest to keep them together in a single series. This patch (of 7): Add __print_flags_u64() and the helper trace_print_flags_seq_u64() in the same spirit as __print_symbolic_u64() and trace_print_symbols_seq_u64(). These functions allow us to print symbols associated with flags that are 64 bits wide even on 32 bit machines. These will be used by the DAX code so that we can print the flags set in a pfn_t such as PFN_SG_CHAIN, PFN_SG_LAST, PFN_DEV and PFN_MAP. Without this new function I was getting errors like the following when compiling for i386: include/linux/pfn_t.h:13:22: warning: large integer implicitly truncated to unsigned type [-Woverflow] #define PFN_SG_CHAIN (1ULL << (BITS_PER_LONG_LONG - 1)) ^ Link: http://lkml.kernel.org/r/1484085142-2297-2-git-send-email-ross.zwisler@linux.intel.com Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com> Reviewed-by: Steven Rostedt <rostedt@goodmis.org> Cc: Dave Chinner <david@fromorbit.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Jan Kara <jack@suse.cz> Cc: Matthew Wilcox <mawilcox@microsoft.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* trace: rename trace_print_hex_seq arg and add kdocDaniel Borkmann2017-02-031-2/+13
| | | | | | | | | | | | Steven suggested to improve trace_print_hex_seq() a bit after commit 2acae0d5b0f7 ("trace: add variant without spacing in trace_print_hex_seq") in two ways: i) by adding a kdoc comment for the helper function itself and ii) by renaming 'spacing' argument into 'concatenate' to better denote that we don't add spaces between each hex bytes. Suggested-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
* trace: add variant without spacing in trace_print_hex_seqDaniel Borkmann2017-01-251-3/+4
| | | | | | | | | | | | For upcoming tracepoint support for BPF, we want to dump the program's tag. Format should be similar to __print_hex(), but without spacing. Add a __print_hex_str() variant for exactly that purpose that reuses trace_print_hex_seq(). Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tracing: Add new trace_marker_rawSteven Rostedt2016-11-151-0/+30
| | | | | | | | | | | | | | A new file is created: /sys/kernel/debug/tracing/trace_marker_raw This allows for appications to create data structures and write the binary data directly into it, and then read the trace data out from trace_pipe_raw into the same type of data structure. This saves on converting numbers into ASCII that would be required by trace_marker. Suggested-by: Olof Johansson <olof@lixom.net> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* tracing: Add NMI tracing in hwlat detectorSteven Rostedt (Red Hat)2016-09-021-1/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | As NMIs can also cause latency when interrupts are disabled, the hwlat detectory has no way to know if the latency it detects is from an NMI or an SMI or some other hardware glitch. As ftrace_nmi_enter/exit() funtions are no longer used (except for sh, which isn't supported anymore), I converted those to "arch_ftrace_nmi_enter/exit" and use ftrace_nmi_enter/exit() to check if hwlat detector is tracing or not, and if so, it calls into the hwlat utility. Since the hwlat detector only has a single kthread that is spinning with interrupts disabled, it marks what CPU it is on, and if the NMI callback happens on that CPU, it records the time spent in that NMI. This is added to the output that is generated by the hwlat detector as: #3 inner/outer(us): 9/9 ts:1470836488.206734548 #4 inner/outer(us): 0/8 ts:1470836497.140808588 #5 inner/outer(us): 0/6 ts:1470836499.140825168 nmi-total:5 nmi-count:1 #6 inner/outer(us): 9/9 ts:1470836501.140841748 All time is still tracked in microseconds. The NMI information is only shown when an NMI occurred during the sample. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* tracing: Added hardware latency tracerSteven Rostedt (Red Hat)2016-09-021-0/+52
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The hardware latency tracer has been in the PREEMPT_RT patch for some time. It is used to detect possible SMIs or any other hardware interruptions that the kernel is unaware of. Note, NMIs may also be detected, but that may be good to note as well. The logic is pretty simple. It simply creates a thread that spins on a single CPU for a specified amount of time (width) within a periodic window (window). These numbers may be adjusted by their cooresponding names in /sys/kernel/tracing/hwlat_detector/ The defaults are window = 1000000 us (1 second) width = 500000 us (1/2 second) The loop consists of: t1 = trace_clock_local(); t2 = trace_clock_local(); Where trace_clock_local() is a variant of sched_clock(). The difference of t2 - t1 is recorded as the "inner" timestamp and also the timestamp t1 - prev_t2 is recorded as the "outer" timestamp. If either of these differences are greater than the time denoted in /sys/kernel/tracing/tracing_thresh then it records the event. When this tracer is started, and tracing_thresh is zero, it changes to the default threshold of 10 us. The hwlat tracer in the PREEMPT_RT patch was originally written by Jon Masters. I have modified it quite a bit and turned it into a tracer. Based-on-code-by: Jon Masters <jcm@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* tracing: Record and show NMI statePeter Zijlstra2016-03-221-3/+7
| | | | | | | | | | | | | The latency tracer format has a nice column to indicate IRQ state, but this is not able to tell us about NMI state. When tracing perf interrupt handlers (which often run in NMI context) it is very useful to see how the events nest. Link: http://lkml.kernel.org/r/20160318153022.105068893@infradead.org Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* tracing: Move trace_flags from global to a trace_array fieldSteven Rostedt (Red Hat)2015-09-301-5/+9
| | | | | | | | | | | | | | | | | In preparation to make trace options per instance, the global trace_flags needs to be moved from being a global variable to a field within the trace instance trace_array structure. There's still more work to do, as there's some functions that use trace_flags without passing in a way to get to the current_trace array. For those, the global_trace is used directly (from trace.c). This includes setting and clearing the trace_flags. This means that when a new instance is created, it just gets the trace_flags of the global_trace and will not be able to modify them. Depending on the functions that have access to the trace_array, the flags of an instance may not affect parts of its trace, where the global_trace is used. These will be fixed in future changes. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* tracing: Turn seq_print_user_ip() into a static functionSteven Rostedt (Red Hat)2015-09-281-2/+2
| | | | | | | | seq_print_user_ip() is used in only one location in one file. Turn it into a static function. We could inject its code into the caller, but that would make the code a bit too complex. Keep the code separate. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* tracing: Inject seq_print_userip_objs() into its only userSteven Rostedt (Red Hat)2015-09-281-45/+36
| | | | | | | | | seq_print_userip_objs() is used only in one location, in one file. Instead of having it as an external function, go one further than making it static, but inject is code into its only user. It doesn't make the calling function much more complex. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* tracing: Introduce two additional marks for delayJungseok Lee2015-07-201-1/+3
| | | | | | | | | | | | | | | | | | | | A fine granulity support for delay would be very useful when profiling VM logics, such as page allocation including page reclaim and memory compaction with function graph. Thus, this patch adds two additional marks with two changes. - An equal sign in mark selection function is removed to align code behavior with comments and documentation. - The function graph example related to delay in ftrace.txt is updated to cover all supported marks. Link: http://lkml.kernel.org/r/1436626300-1679-3-git-send-email-jungseoklee85@gmail.com Cc: Byungchul Park <byungchul.park@lge.com> Signed-off-by: Jungseok Lee <jungseoklee85@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* tracing: Rename ftrace_event_name() to trace_event_name()Steven Rostedt (Red Hat)2015-05-131-1/+1
| | | | | | | | | The name "ftrace" really refers to the function hook infrastructure. It is not about the trace_events. ftrace_event_name() returns the name of an event tracepoint, has nothing to do with function tracing. Rename it to trace_event_name(). Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* tracing: Rename FTRACE_MAX_EVENT to TRACE_EVENT_TYPE_MAXSteven Rostedt (Red Hat)2015-05-131-2/+2
| | | | | | | | The name "ftrace" really refers to the function hook infrastructure. It is not about the trace_events. Rename the max trace_event type size to something more descriptive and appropriate. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* tracing: Rename ftrace_output functions to trace_outputSteven Rostedt (Red Hat)2015-05-131-8/+8
| | | | | | | | | The name "ftrace" really refers to the function hook infrastructure. It is not about the trace_events. The ftrace_output_*() and ftrace_raw_output_*() functions represent the trace_event code. Rename them to just trace_output or trace_raw_output. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* tracing: Rename ftrace_event_{call,class} to trace_event_{call,class}Steven Rostedt (Red Hat)2015-05-131-2/+2
| | | | | | | | | The name "ftrace" really refers to the function hook infrastructure. It is not about the trace_events. The structures ftrace_event_call and ftrace_event_class have nothing to do with the function hooks, and are really trace_event structures. Rename ftrace_event_* to trace_event_*. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* tracing: Rename (un)register_ftrace_event() to (un)register_trace_event()Steven Rostedt (Red Hat)2015-05-131-9/+9
| | | | | | | | | | | The name "ftrace" really refers to the function hook infrastructure. It is not about the trace_events. The functions (un)register_ftrace_event() is really about trace_events, and the name should be register_trace_event() instead. Also renamed ftrace_event_reg() to trace_event_reg() for the same reason. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* tracing: Rename ftrace_print_*() functions ta trace_print_*()Steven Rostedt (Red Hat)2015-05-131-17/+17
| | | | | | | | | The name "ftrace" really refers to the function hook infrastructure. It is not about the trace_events. The functions ftrace_print_*() are not part of the function infrastructure, and the names can be confusing. Rename them to be trace_print_*(). Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* tracing: Make ftrace_print_array_seq compute buf_lenAlex Bennée2015-05-061-1/+2
| | | | | | | | | | | | The only caller to this function (__print_array) was getting it wrong by passing the array length instead of buffer length. As the element size was already being passed for other reasons it seems reasonable to push the calculation of buffer length into the function. Link: http://lkml.kernel.org/r/1430320727-14582-1-git-send-email-alex.bennee@linaro.org Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* tracing: Add array printing helperDave Martin2015-01-281-0/+44
| | | | | | | | | | | | | | | | | | | | | | | | | | | | If a trace event contains an array, there is currently no standard way to format this for text output. Drivers are currently hacking around this by a) local hacks that use the trace_seq functionailty directly, or b) just not printing that information. For fixed size arrays, formatting of the elements can be open-coded, but this gets cumbersome for arrays of non-trivial size. These approaches result in non-standard content of the event format description delivered to userspace, so userland tools needs to be taught to understand and parse each array printing method individually. This patch implements a __print_array() helper that tracepoint implementations can use instead of reinventing it. A simple C-style syntax is used to delimit the array and its elements {like,this}. So that the helpers can be used with large static arrays as well as dynamic arrays, they take a pointer and element count: they can be used with __get_dynamic_array() for use with dynamic arrays. Link: http://lkml.kernel.org/r/1422449335-8289-2-git-send-email-javi.merino@arm.com Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Javi Merino <javi.merino@arm.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* tracing: Add additional marks to signal very large time deltasByungchul Park2014-12-031-5/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, function graph tracer prints "!" or "+" just before function execution time to signal a function overhead, depending on the time. And some tracers tracing latency also print "!" or "+" just after time to signal overhead, depending on the interval between events. Even it is usually enough to do that, we sometimes need to signal for bigger execution time than 100 micro seconds. For example, I used function graph tracer to detect if there is any case that exit_mm() takes too much time. I did following steps in /sys/kernel/debug/tracing. It was easier to detect very large excution time with patched kernel than with original kernel. $ echo exit_mm > set_graph_function $ echo function_graph > current_tracer $ echo > trace $ cat trace_pipe > $LOGFILE ... (do something and terminate logging) $ grep "\\$" $LOGFILE 3) $ 22082032 us | } /* kernel_map_pages */ 3) $ 22082040 us | } /* free_pages_prepare */ 3) $ 22082113 us | } /* free_hot_cold_page */ 3) $ 22083455 us | } /* free_hot_cold_page_list */ 3) $ 22083895 us | } /* release_pages */ 3) $ 22177873 us | } /* free_pages_and_swap_cache */ 3) $ 22178929 us | } /* unmap_single_vma */ 3) $ 22198885 us | } /* unmap_vmas */ 3) $ 22206949 us | } /* exit_mmap */ 3) $ 22207659 us | } /* mmput */ 3) $ 22207793 us | } /* exit_mm */ And then, it was easy to find out that a schedule-out occured by sub_preempt_count() within kernel_map_pages(). To detect very large function exection time caused by either problematic function implementation or scheduling issues, this patch can be useful. Link: http://lkml.kernel.org/r/1416789259-24038-1-git-send-email-byungchul.park@lge.com Signed-off-by: Byungchul Park <byungchul.park@lge.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>