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2018-02-11vfs: do bulk POLL* -> EPOLL* replacementLinus Torvalds
This is the mindless scripted replacement of kernel use of POLL* variables as described by Al, done by this script: for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'` for f in $L; do sed -i "-es/^\([^\"]*\)\(\<POLL$V\>\)/\\1E\\2/" $f; done done with de-mangling cleanups yet to come. NOTE! On almost all architectures, the EPOLL* constants have the same values as the POLL* constants do. But they keyword here is "almost". For various bad reasons they aren't the same, and epoll() doesn't actually work quite correctly in some cases due to this on Sparc et al. The next patch from Al will sort out the final differences, and we should be all done. Scripted-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-01Merge tag 'trace-v4.16' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: "There's not much changes for the tracing system this release. Mostly small clean ups and fixes. The biggest change is to how bprintf works. bprintf is used by trace_printk() to just save the format and args of a printf call, and the formatting is done when the trace buffer is read. This is done to keep the formatting out of the fast path (this was recommended by you). The issue is when arguments are de-referenced. If a pointer is saved, and the format has something like "%*pbl", when the buffer is read, it will de-reference the argument then. The problem is if the data no longer exists. This can cause the kernel to oops. The fix for this was to make these de-reference pointes do the formatting at the time it is called (the fast path), as this guarantees that the data exists (and doesn't change later)" * tag 'trace-v4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: vsprintf: Do not have bprintf dereference pointers ftrace: Mark function tracer test functions noinline/noclone trace_uprobe: Display correct offset in uprobe_events tracing: Make sure the parsed string always terminates with '\0' tracing: Clear parser->idx if only spaces are read tracing: Detect the string nul character when parsing user input string
2018-01-30Merge branch 'misc.poll' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull poll annotations from Al Viro: "This introduces a __bitwise type for POLL### bitmap, and propagates the annotations through the tree. Most of that stuff is as simple as 'make ->poll() instances return __poll_t and do the same to local variables used to hold the future return value'. Some of the obvious brainos found in process are fixed (e.g. POLLIN misspelled as POLL_IN). At that point the amount of sparse warnings is low and most of them are for genuine bugs - e.g. ->poll() instance deciding to return -EINVAL instead of a bitmap. I hadn't touched those in this series - it's large enough as it is. Another problem it has caught was eventpoll() ABI mess; select.c and eventpoll.c assumed that corresponding POLL### and EPOLL### were equal. That's true for some, but not all of them - EPOLL### are arch-independent, but POLL### are not. The last commit in this series separates userland POLL### values from the (now arch-independent) kernel-side ones, converting between them in the few places where they are copied to/from userland. AFAICS, this is the least disruptive fix preserving poll(2) ABI and making epoll() work on all architectures. As it is, it's simply broken on sparc - try to give it EPOLLWRNORM and it will trigger only on what would've triggered EPOLLWRBAND on other architectures. EPOLLWRBAND and EPOLLRDHUP, OTOH, are never triggered at all on sparc. With this patch they should work consistently on all architectures" * 'misc.poll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (37 commits) make kernel-side POLL... arch-independent eventpoll: no need to mask the result of epi_item_poll() again eventpoll: constify struct epoll_event pointers debugging printk in sg_poll() uses %x to print POLL... bitmap annotate poll(2) guts 9p: untangle ->poll() mess ->si_band gets POLL... bitmap stored into a user-visible long field ring_buffer_poll_wait() return value used as return value of ->poll() the rest of drivers/*: annotate ->poll() instances media: annotate ->poll() instances fs: annotate ->poll() instances ipc, kernel, mm: annotate ->poll() instances net: annotate ->poll() instances apparmor: annotate ->poll() instances tomoyo: annotate ->poll() instances sound: annotate ->poll() instances acpi: annotate ->poll() instances crypto: annotate ->poll() instances block: annotate ->poll() instances x86: annotate ->poll() instances ...
2018-01-30Merge branch 'core-rcu-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RCU updates from Ingo Molnar: "The main RCU changes in this cycle were: - Updates to use cond_resched() instead of cond_resched_rcu_qs() where feasible (currently everywhere except in kernel/rcu and in kernel/torture.c). Also a couple of fixes to avoid sending IPIs to offline CPUs. - Updates to simplify RCU's dyntick-idle handling. - Updates to remove almost all uses of smp_read_barrier_depends() and read_barrier_depends(). - Torture-test updates. - Miscellaneous fixes" * 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (72 commits) torture: Save a line in stutter_wait(): while -> for torture: Eliminate torture_runnable and perf_runnable torture: Make stutter less vulnerable to compilers and races locking/locktorture: Fix num reader/writer corner cases locking/locktorture: Fix rwsem reader_delay torture: Place all torture-test modules in one MAINTAINERS group rcutorture/kvm-build.sh: Skip build directory check rcutorture: Simplify functions.sh include path rcutorture: Simplify logging rcutorture/kvm-recheck-*: Improve result directory readability check rcutorture/kvm.sh: Support execution from any directory rcutorture/kvm.sh: Use consistent help text for --qemu-args rcutorture/kvm.sh: Remove unused variable, `alldone` rcutorture: Remove unused script, config2frag.sh rcutorture/configinit: Fix build directory error message rcutorture: Preempt RCU-preempt readers more vigorously torture: Reduce #ifdefs for preempt_schedule() rcu: Remove have_rcu_nocb_mask from tree_plugin.h rcu: Add comment giving debug strategy for double call_rcu() tracing, rcu: Hide trace event rcu_nocb_wake when not used ...
2018-01-23tracing: Make sure the parsed string always terminates with '\0'Changbin Du
Always mark the parsed string with a terminated nul '\0' character. This removes the need for the users to have to append the '\0' before using the parsed string. Link: http://lkml.kernel.org/r/1516093350-12045-4-git-send-email-changbin.du@intel.com Acked-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Changbin Du <changbin.du@intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-01-23tracing: Clear parser->idx if only spaces are readChangbin Du
If only spaces were read while parsing the next string, then parser->idx should be cleared in order to make trace_parser_loaded() return false. Link: http://lkml.kernel.org/r/1516093350-12045-3-git-send-email-changbin.du@intel.com Acked-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Changbin Du <changbin.du@intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-01-23tracing: Detect the string nul character when parsing user input stringChangbin Du
User space can pass in a C nul character '\0' along with its input. The function trace_get_user() will try to process it as a normal character, and that will fail to parse. open("/sys/kernel/debug/tracing//set_ftrace_pid", O_WRONLY|O_TRUNC) = 3 write(3, " \0", 2) = -1 EINVAL (Invalid argument) while parse can handle spaces, so below works. $ echo "" > set_ftrace_pid $ echo " " > set_ftrace_pid $ echo -n " " > set_ftrace_pid Have the parser stop on '\0' and cease any further parsing. Only process the characters up to the nul '\0' character and do not process it. Link: http://lkml.kernel.org/r/1516093350-12045-2-git-send-email-changbin.du@intel.com Acked-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Changbin Du <changbin.du@intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-01-23tracing: Update stack trace skipping for ORC unwinderSteven Rostedt (VMware)
With the addition of ORC unwinder and FRAME POINTER unwinder, the stack trace skipping requirements have changed. I went through the tracing stack trace dumps with ORC and with frame pointers and recalculated the proper values. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-01-03Merge branch 'for-mingo' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu Pull RCU updates from Paul E. McKenney: - Updates to use cond_resched() instead of cond_resched_rcu_qs() where feasible (currently everywhere except in kernel/rcu and in kernel/torture.c). Also a couple of fixes to avoid sending IPIs to offline CPUs. - Updates to simplify RCU's dyntick-idle handling. - Updates to remove almost all uses of smp_read_barrier_depends() and read_barrier_depends(). - Miscellaneous fixes. - Torture-test updates. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-27tracing: Fix possible double free on failure of allocating trace bufferSteven Rostedt (VMware)
Jing Xia and Chunyan Zhang reported that on failing to allocate part of the tracing buffer, memory is freed, but the pointers that point to them are not initialized back to NULL, and later paths may try to free the freed memory again. Jing and Chunyan fixed one of the locations that does this, but missed a spot. Link: http://lkml.kernel.org/r/20171226071253.8968-1-chunyan.zhang@spreadtrum.com Cc: stable@vger.kernel.org Fixes: 737223fbca3b1 ("tracing: Consolidate buffer allocation code") Reported-by: Jing Xia <jing.xia@spreadtrum.com> Reported-by: Chunyan Zhang <chunyan.zhang@spreadtrum.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-27tracing: Fix crash when it fails to alloc ring bufferJing Xia
Double free of the ring buffer happens when it fails to alloc new ring buffer instance for max_buffer if TRACER_MAX_TRACE is configured. The root cause is that the pointer is not set to NULL after the buffer is freed in allocate_trace_buffers(), and the freeing of the ring buffer is invoked again later if the pointer is not equal to Null, as: instance_mkdir() |-allocate_trace_buffers() |-allocate_trace_buffer(tr, &tr->trace_buffer...) |-allocate_trace_buffer(tr, &tr->max_buffer...) // allocate fail(-ENOMEM),first free // and the buffer pointer is not set to null |-ring_buffer_free(tr->trace_buffer.buffer) // out_free_tr |-free_trace_buffers() |-free_trace_buffer(&tr->trace_buffer); //if trace_buffer is not null, free again |-ring_buffer_free(buf->buffer) |-rb_free_cpu_buffer(buffer->buffers[cpu]) // ring_buffer_per_cpu is null, and // crash in ring_buffer_per_cpu->pages Link: http://lkml.kernel.org/r/20171226071253.8968-1-chunyan.zhang@spreadtrum.com Cc: stable@vger.kernel.org Fixes: 737223fbca3b1 ("tracing: Consolidate buffer allocation code") Signed-off-by: Jing Xia <jing.xia@spreadtrum.com> Signed-off-by: Chunyan Zhang <chunyan.zhang@spreadtrum.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-27tracing: Remove extra zeroing out of the ring buffer pageSteven Rostedt (VMware)
The ring_buffer_read_page() takes care of zeroing out any extra data in the page that it returns. There's no need to zero it out again from the consumer. It was removed from one consumer of this function, but read_buffers_splice_read() did not remove it, and worse, it contained a nasty bug because of it. Cc: stable@vger.kernel.org Fixes: 2711ca237a084 ("ring-buffer: Move zeroing out excess in page to ring buffer code") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-04tracing: Pass export pointer as argument to ->write()Felipe Balbi
By passing an export descriptor to the write function, users don't need to keep a global static pointer and can rely on container_of() to fetch their own structure. Link: http://lkml.kernel.org/r/20170602102025.5140-1-felipe.balbi@linux.intel.com Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Reviewed-by: Chunyan Zhang <zhang.chunyan@linaro.org> Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-04tracing: Allocate mask_str buffer dynamicallyChangbin Du
The default NR_CPUS can be very large, but actual possible nr_cpu_ids usually is very small. For my x86 distribution, the NR_CPUS is 8192 and nr_cpu_ids is 4. About 2 pages are wasted. Most machines don't have so many CPUs, so define a array with NR_CPUS just wastes memory. So let's allocate the buffer dynamically when need. With this change, the mutext tracing_cpumask_update_lock also can be removed now, which was used to protect mask_str. Link: http://lkml.kernel.org/r/1512013183-19107-1-git-send-email-changbin.du@intel.com Fixes: 36dfe9252bd4c ("ftrace: make use of tracing_cpumask") Cc: stable@vger.kernel.org Signed-off-by: Changbin Du <changbin.du@intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-04tracing: Fix code comments in trace.cChunyu Hu
Naming in code comments for tracing_snapshot, tracing_snapshot_alloc and trace_pid_filter_add_remove_task don't match the real function names. And latency_trace has been removed from tracing directory. Fix them. Link: http://lkml.kernel.org/r/1508394753-20887-1-git-send-email-chuhu@redhat.com Fixes: cab5037 ("tracing/ftrace: Enable snapshot function trigger") Fixes: 886b5b7 ("tracing: remove /debug/tracing/latency_trace") Signed-off-by: Chunyu Hu <chuhu@redhat.com> [ Replaced /sys/kernel/debug/tracing with /sys/kerne/tracing ] Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-11-27ipc, kernel, mm: annotate ->poll() instancesAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-11-27rcu: Eliminate rcu_irq_enter_disabled()Paul E. McKenney
Now that the irq path uses the rcu_nmi_{enter,exit}() algorithm, rcu_irq_enter() and rcu_irq_exit() may be used from any context. There is thus no need for rcu_irq_enter_disabled() and for the checks using it. This commit therefore eliminates rcu_irq_enter_disabled(). Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-10-04tracing: Make traceprobe parsing code reusableTom Zanussi
traceprobe_probes_write() and traceprobe_command() actually contain nothing that ties them to kprobes - the code is generically useful for similar types of parsing elsewhere, so separate it out and move it to trace.c/trace.h. Other than moving it, the only change is in naming: traceprobe_probes_write() becomes trace_parse_run_command() and traceprobe_command() becomes trace_run_command(). Link: http://lkml.kernel.org/r/ae5c26ea40c196a8986854d921eb6e713ede7e3f.1506105045.git.tom.zanussi@linux.intel.com Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-10-04tracing: Reverse the order of trace_types_lock and event_mutexSteven Rostedt (VMware)
In order to make future changes where we need to call tracing_set_clock() from within an event command, the order of trace_types_lock and event_mutex must be reversed, as the event command will hold event_mutex and the trace_types_lock is taken from within tracing_set_clock(). Link: http://lkml.kernel.org/r/20170921162249.0dde3dca@gandalf.local.home Requested-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-09-19tracing: Fix trace_pipe behavior for instance tracesTahsin Erdogan
When reading data from trace_pipe, tracing_wait_pipe() performs a check to see if tracing has been turned off after some data was read. Currently, this check always looks at global trace state, but it should be checking the trace instance where trace_pipe is located at. Because of this bug, cat instances/i1/trace_pipe in the following script will immediately exit instead of waiting for data: cd /sys/kernel/debug/tracing echo 0 > tracing_on mkdir -p instances/i1 echo 1 > instances/i1/tracing_on echo 1 > instances/i1/events/sched/sched_process_exec/enable cat instances/i1/trace_pipe Link: http://lkml.kernel.org/r/20170917102348.1615-1-tahsin@google.com Cc: stable@vger.kernel.org Fixes: 10246fa35d4f ("tracing: give easy way to clear trace buffer") Signed-off-by: Tahsin Erdogan <tahsin@google.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-09-19tracing: Ignore mmiotrace from kernel commandlineZiqian SUN (Zamir)
The mmiotrace tracer cannot be enabled with ftrace=mmiotrace in kernel commandline. With this patch, noboot is added to the tracer struct, and when system boot with a tracer that has noboot=true, it will print out a warning message and continue booting. Link: http://lkml.kernel.org/r/1505111195-31942-1-git-send-email-zsun@redhat.com Signed-off-by: Ziqian SUN (Zamir) <zsun@redhat.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-09-19tracing: Erase irqsoff trace with empty writeBo Yan
One convenient way to erase trace is "echo > trace". However, this is currently broken if the current tracer is irqsoff tracer. This is because irqsoff tracer use max_buffer as the default trace buffer. Set the max_buffer as the one to be cleared when it's the trace buffer currently in use. Link: http://lkml.kernel.org/r/1505754215-29411-1-git-send-email-byan@nvidia.com Cc: <mingo@redhat.com> Cc: stable@vger.kernel.org Fixes: 4acd4d00f ("tracing: give easy way to clear trace buffer") Signed-off-by: Bo Yan <byan@nvidia.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-09-06tracing: Apply trace_clock changes to instance max bufferBaohong Liu
Currently trace_clock timestamps are applied to both regular and max buffers only for global trace. For instance trace, trace_clock timestamps are applied only to regular buffer. But, regular and max buffers can be swapped, for example, following a snapshot. So, for instance trace, bad timestamps can be seen following a snapshot. Let's apply trace_clock timestamps to instance max buffer as well. Link: http://lkml.kernel.org/r/ebdb168d0be042dcdf51f81e696b17fabe3609c1.1504642143.git.tom.zanussi@linux.intel.com Cc: stable@vger.kernel.org Fixes: 277ba0446 ("tracing: Add interface to allow multiple trace buffers") Signed-off-by: Baohong Liu <baohong.liu@intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-09-05tracing: Add barrier to trace_printk() buffer nesting modificationSteven Rostedt (VMware)
trace_printk() uses 4 buffers, one for each context (normal, softirq, irq and NMI), such that it does not need to worry about one context preempting the other. There's a nesting counter that gets incremented to figure out which buffer to use. If the context gets preempted by another context which calls trace_printk() it will increment the counter and use the next buffer, and restore the counter when it is finished. The problem is that gcc may optimize the modification of the buffer nesting counter and it may not be incremented in memory before the buffer is used. If this happens, and the context gets interrupted by another context, it could pick the same buffer and corrupt the one that is being used. Compiler barriers need to be added after the nesting variable is incremented and before it is decremented to prevent usage of the context buffers by more than one context at the same time. Cc: Andy Lutomirski <luto@kernel.org> Cc: stable@vger.kernel.org Fixes: e2ace00117 ("tracing: Choose static tp_printk buffer by explicit nesting count") Hat-tip-to: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-08-31tracing: Only have rmmod clear buffers that its events were active inSteven Rostedt (VMware)
Currently, when a module event is enabled, when that module is removed, it clears all ring buffers. This is to prevent another module from being loaded and having one of its trace event IDs from reusing a trace event ID of the removed module. This could cause undesirable effects as the trace event of the new module would be using its own processing algorithms to process raw data of another event. To prevent this, when a module is loaded, if any of its events have been used (signified by the WAS_ENABLED event call flag, which is never cleared), all ring buffers are cleared, just in case any one of them contains event data of the removed event. The problem is, there's no reason to clear all ring buffers if only one (or less than all of them) uses one of the events. Instead, only clear the ring buffers that recorded the events of a module that is being removed. To do this, instead of keeping the WAS_ENABLED flag with the trace event call, move it to the per instance (per ring buffer) event file descriptor. The event file descriptor maps each event to a separate ring buffer instance. Then when the module is removed, only the ring buffers that activated one of the module's events get cleared. The rest are not touched. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-08-02ring-buffer: Have ring_buffer_alloc_read_page() return error on offline CPUSteven Rostedt (VMware)
Chunyu Hu reported: "per_cpu trace directories and files are created for all possible cpus, but only the cpus which have ever been on-lined have their own per cpu ring buffer (allocated by cpuhp threads). While trace_buffers_open, the open handler for trace file 'trace_pipe_raw' is always trying to access field of ring_buffer_per_cpu, and would panic with the NULL pointer. Align the behavior of trace_pipe_raw with trace_pipe, that returns -NODEV when openning it if that cpu does not have trace ring buffer. Reproduce: cat /sys/kernel/debug/tracing/per_cpu/cpu31/trace_pipe_raw (cpu31 is never on-lined, this is a 16 cores x86_64 box) Tested with: 1) boot with maxcpus=14, read trace_pipe_raw of cpu15. Got -NODEV. 2) oneline cpu15, read trace_pipe_raw of cpu15. Get the raw trace data. Call trace: [ 5760.950995] RIP: 0010:ring_buffer_alloc_read_page+0x32/0xe0 [ 5760.961678] tracing_buffers_read+0x1f6/0x230 [ 5760.962695] __vfs_read+0x37/0x160 [ 5760.963498] ? __vfs_read+0x5/0x160 [ 5760.964339] ? security_file_permission+0x9d/0xc0 [ 5760.965451] ? __vfs_read+0x5/0x160 [ 5760.966280] vfs_read+0x8c/0x130 [ 5760.967070] SyS_read+0x55/0xc0 [ 5760.967779] do_syscall_64+0x67/0x150 [ 5760.968687] entry_SYSCALL64_slow_path+0x25/0x25" This was introduced by the addition of the feature to reuse reader pages instead of re-allocating them. The problem is that the allocation of a reader page (which is per cpu) does not check if the cpu is online and set up for the ring buffer. Link: http://lkml.kernel.org/r/1500880866-1177-1-git-send-email-chuhu@redhat.com Cc: stable@vger.kernel.org Fixes: 73a757e63114 ("ring-buffer: Return reader page back into existing ring buffer") Reported-by: Chunyu Hu <chuhu@redhat.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-08-02tracing: Missing error code in tracer_alloc_buffers()Dan Carpenter
If ring_buffer_alloc() or one of the next couple function calls fail then we should return -ENOMEM but the current code returns success. Link: http://lkml.kernel.org/r/20170801110201.ajdkct7vwzixahvx@mwanda Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: stable@vger.kernel.org Fixes: b32614c03413 ('tracing/rb: Convert to hotplug state machine') Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-08-02tracing: Call clear_boot_tracer() at lateinit_syncSteven Rostedt (VMware)
The clear_boot_tracer function is used to reset the default_bootup_tracer string to prevent it from being accessed after boot, as it originally points to init data. But since clear_boot_tracer() is called via the init_lateinit() call, it races with the initcall for registering the hwlat tracer. If someone adds "ftrace=hwlat" to the kernel command line, depending on how the linker sets up the text, the saved command line may be cleared, and the hwlat tracer never is initialized. Simply have the clear_boot_tracer() be called by initcall_lateinit_sync() as that's for tasks to be called after lateinit. Link: https://bugzilla.kernel.org/show_bug.cgi?id=196551 Cc: stable@vger.kernel.org Fixes: e7c15cd8a ("tracing: Added hardware latency tracer") Reported-by: Zamir SUN <sztsian@gmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-07-20tracing: Fix kmemleak in instance_rmdirChunyu Hu
Hit the kmemleak when executing instance_rmdir, it forgot releasing mem of tracing_cpumask. With this fix, the warn does not appear any more. unreferenced object 0xffff93a8dfaa7c18 (size 8): comm "mkdir", pid 1436, jiffies 4294763622 (age 9134.308s) hex dump (first 8 bytes): ff ff ff ff ff ff ff ff ........ backtrace: [<ffffffff88b6567a>] kmemleak_alloc+0x4a/0xa0 [<ffffffff8861ea41>] __kmalloc_node+0xf1/0x280 [<ffffffff88b505d3>] alloc_cpumask_var_node+0x23/0x30 [<ffffffff88b5060e>] alloc_cpumask_var+0xe/0x10 [<ffffffff88571ab0>] instance_mkdir+0x90/0x240 [<ffffffff886e5100>] tracefs_syscall_mkdir+0x40/0x70 [<ffffffff886565c9>] vfs_mkdir+0x109/0x1b0 [<ffffffff8865b1d0>] SyS_mkdir+0xd0/0x100 [<ffffffff88403857>] do_syscall_64+0x67/0x150 [<ffffffff88b710e7>] return_from_SYSCALL_64+0x0/0x6a [<ffffffffffffffff>] 0xffffffffffffffff Link: http://lkml.kernel.org/r/1500546969-12594-1-git-send-email-chuhu@redhat.com Cc: stable@vger.kernel.org Fixes: ccfe9e42e451 ("tracing: Make tracing_cpumask available for all instances") Signed-off-by: Chunyu Hu <chuhu@redhat.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-07-13Merge tag 'trace-v4.13-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull more tracing updates from Steven Rostedt: "A few more minor updates: - Show the tgid mappings for user space trace tools to use - Fix and optimize the comm and tgid cache recording - Sanitize derived kprobe names - Ftrace selftest updates - trace file header fix - Update of Documentation/trace/ftrace.txt - Compiler warning fixes - Fix possible uninitialized variable" * tag 'trace-v4.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: ftrace: Fix uninitialized variable in match_records() ftrace: Remove an unneeded NULL check ftrace: Hide cached module code for !CONFIG_MODULES tracing: Do note expose stack_trace_filter without DYNAMIC_FTRACE tracing: Update Documentation/trace/ftrace.txt tracing: Fixup trace file header alignment selftests/ftrace: Add a testcase for kprobe event naming selftests/ftrace: Add a test to probe module functions selftests/ftrace: Update multiple kprobes test for powerpc trace/kprobes: Sanitize derived event names tracing: Attempt to record other information even if some fail tracing: Treat recording tgid for idle task as a success tracing: Treat recording comm for idle task as a success tracing: Add saved_tgids file to show cached pid to tgid mappings
2017-07-11tracing: Fixup trace file header alignmentSteven Rostedt (VMware)
The addition of TGID to the tracing header added a check to see if TGID shoudl be displayed or not, and updated the header accordingly. Unfortunately, it broke the default header. Also add constant strings to use for spacing. This does remove the visibility of the header a bit, but cuts it down from the extended lines much greater than 80 characters. Before this change: # tracer: function # # _-----=> irqs-off # / _----=> need-resched # | / _---=> hardirq/softirq # || / _--=> preempt-depth # ||| / delay # TASK-PID CPU#|||| TIMESTAMP FUNCTION # | | | |||| | | swapper/0-1 [000] .... 0.277830: migration_init <-do_one_initcall swapper/0-1 [002] d... 13.861967: Unknown type 1201 swapper/0-1 [002] d..1 13.861970: Unknown type 1202 After this change: # tracer: function # # _-----=> irqs-off # / _----=> need-resched # | / _---=> hardirq/softirq # || / _--=> preempt-depth # ||| / delay # TASK-PID CPU# |||| TIMESTAMP FUNCTION # | | | |||| | | swapper/0-1 [000] .... 0.278245: migration_init <-do_one_initcall swapper/0-1 [003] d... 13.861189: Unknown type 1201 swapper/0-1 [003] d..1 13.861192: Unknown type 1202 Cc: Joel Fernandes <joelaf@google.com> Fixes: 441dae8f2f29 ("tracing: Add support for display of tgid in trace output") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-07-07Merge tag 'linux-kselftest-4.13-rc1-update' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest Pull Kselftest updates from Shuah Khan: "This update consists of: - TAP13 framework and changes to some tests to convert to TAP13. Converting kselftest output to standard format will help identify run to run differences and pin point failures easily. TAP13 format has been in use for several years and the output is human friendly. Please find the specification: https://testanything.org/tap-version-13-specification.html Credit goes to Tim Bird for recommending TAP13 as a suitable format, and to Grag KH for kick starting the work with help from Paul Elder and Alice Ferrazzi The first phase of the TAp13 conversion is included in this update. Future updates will include updates to rest of the tests. - Masami Hiramatsu fixed ftrace to run on 4.9 stable kernels. - Kselftest documnetation has been converted to ReST format. Document now has a new home under Documentation/dev-tools. - kselftest_harness.h is now available for general use as a result of Mickaël Salaün's work. - Several fixes to skip and/or fail tests gracefully on older releases" * tag 'linux-kselftest-4.13-rc1-update' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: (48 commits) selftests: membarrier: use ksft_* var arg msg api selftests: breakpoints: breakpoint_test_arm64: convert test to use TAP13 selftests: breakpoints: step_after_suspend_test use ksft_* var arg msg api selftests: breakpoint_test: use ksft_* var arg msg api kselftest: add ksft_print_msg() function to output general information kselftest: make ksft_* output functions variadic selftests/capabilities: Fix the test_execve test selftests: intel_pstate: add .gitignore selftests: fix memory-hotplug test selftests: add missing test name in memory-hotplug test selftests: check percentage range for memory-hotplug test selftests: check hot-pluggagble memory for memory-hotplug test selftests: typo correction for memory-hotplug test selftests: ftrace: Use md5sum to take less time of checking logs tools/testing/selftests/sysctl: Add pre-check to the value of writes_strict kselftest.rst: do some adjustments after ReST conversion selftest/net/Makefile: Specify output with $(OUTPUT) selftest/intel_pstate/aperf: Use LDLIBS instead of LDFLAGS selftest/memfd/Makefile: Fix build error selftests: lib: Skip tests on missing test modules ...
2017-07-07tracing: Attempt to record other information even if some failJoel Fernandes
In recent patches where we record comm and tgid at the same time, we skip continuing to record if any fail. Fix that by trying to record as many things as we can even if some couldn't be recorded. If any information isn't recorded, then we don't set trace_taskinfo_save as before. Link: http://lkml.kernel.org/r/20170706230023.17942-3-joelaf@google.com Cc: kernel-team@android.com Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by: Joel Fernandes <joelaf@google.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-07-07tracing: Treat recording tgid for idle task as a successJoel Fernandes
Currently we stop recording tgid for non-idle tasks when switching from/to idle task since we treat that as a record failure. Fix that by treat recording of tgid for idle task as a success. Link: http://lkml.kernel.org/r/20170706230023.17942-2-joelaf@google.com Cc: kernel-team@android.com Cc: Ingo Molnar <mingo@redhat.com> Reported-by: Michael Sartain <mikesart@gmail.com> Signed-off-by: Joel Fernandes <joelaf@google.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-07-07tracing: Treat recording comm for idle task as a successJoel Fernandes
Currently we stop recording comm for non-idle tasks when switching from/to idle task since we treat that as a record failure. Fix that by treat recording of comm for idle task as a success. Link: http://lkml.kernel.org/r/20170706230023.17942-1-joelaf@google.com Cc: kernel-team@android.com Cc: Ingo Molnar <mingo@redhat.com> Reported-by: Michael Sartain <mikesart@gmail.com> Signed-off-by: Joel Fernandes <joelaf@google.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-07-06tracing: Add saved_tgids file to show cached pid to tgid mappingsMichael Sartain
Export the cached pid / tgid mappings in debugfs tracing saved_tgids file. This allows user apps to translate the pids from a trace to their respective thread group. Example saved_tgids file with pid / tgid values separated by ' ': # cat saved_tgids 1048 1048 1047 1047 7 7 1049 1047 1054 1047 1053 1047 Link: http://lkml.kernel.org/r/20170630004023.064965233@goodmis.org Link: http://lkml.kernel.org/r/20170706040713.unwkumbta5menygi@mikesart-cos Reviewed-by: Joel Fernandes <joelaf@google.com> Signed-off-by: Michael Sartain <mikesart@fastmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-07-05Merge commit '0f17976568b3f72e676450af0c0db6f8752253d6' into trace/ftrace/coreSteven Rostedt (VMware)
Need to get the changes from 0f17976568b3 ("ftrace: Fix regression with module command in stack_trace_filter") as it is required to fix some other changes with stack_trace_filter and the new development code. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-06-29ftrace: Fix regression with module command in stack_trace_filterSteven Rostedt (VMware)
When doing the following command: # echo ":mod:kvm_intel" > /sys/kernel/tracing/stack_trace_filter it triggered a crash. This happened with the clean up of probes. It required all callers to the regex function (doing ftrace filtering) to have ops->private be a pointer to a trace_array. But for the stack tracer, that is not the case. Allow for the ops->private to be NULL, and change the function command callbacks to handle the trace_array pointer being NULL as well. Fixes: d2afd57a4b96 ("tracing/ftrace: Allow instances to have their own function probes") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-06-27tracing: Add support for display of tgid in trace outputJoel Fernandes
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>
2017-06-27tracing: Add support for recording tgid of tasksJoel Fernandes
Inorder to support recording of tgid, the following changes are made: * Introduce a new API (tracing_record_taskinfo) to additionally record the tgid along with the task's comm at the same time. This has has the benefit of not setting trace_cmdline_save before all the information for a task is saved. * Add a new API tracing_record_taskinfo_sched_switch to record task information for 2 tasks at a time (previous and next) and use it from sched_switch probe. * Preserve the old API (tracing_record_cmdline) and create it as a wrapper around the new one so that existing callers aren't affected. * Reuse the existing sched_switch and sched_wakeup probes to record tgid information and add a new option 'record-tgid' to enable recording of tgid When record-tgid option isn't enabled to being with, we take care to make sure that there's isn't memory or runtime overhead. Link: http://lkml.kernel.org/r/20170627020155.5139-1-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>
2017-06-27ftrace: Remove unused function ftrace_arch_read_dyn_info()Steven Rostedt (VMware)
ftrace_arch_read_dyn_info() was used so that archs could add its own debug information into the dyn_ftrace_total_info in the tracefs file system. That file is for debugging usage of dynamic ftrace. No arch uses that function anymore, so just get rid of it. This also allows for tracing_read_dyn_info() to be cleaned up a bit. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-06-13tracing: Rename update the enum_map fileJeremy Linton
The enum_map file is used to display a list of symbol to name conversions. As its now used to resolve sizeof lets update the name and description. Link: http://lkml.kernel.org/r/20170531215653.3240-13-jeremy.linton@arm.com Signed-off-by: Jeremy Linton <jeremy.linton@arm.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-06-13trace: rename enum_map functionsJeremy Linton
Rename the core trace enum routines to use eval, to reflect their use by more than just enum to value mapping. Link: http://lkml.kernel.org/r/20170531215653.3240-8-jeremy.linton@arm.com Signed-off-by: Jeremy Linton <jeremy.linton@arm.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-06-13trace: rename trace.c enum functionsJeremy Linton
Rename the init and trace_enum_jmp_to_tail() routines to reflect their use by more than enumerated types. Link: http://lkml.kernel.org/r/20170531215653.3240-7-jeremy.linton@arm.com Signed-off-by: Jeremy Linton <jeremy.linton@arm.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-06-13trace: rename trace_enum_mutex to trace_eval_mutexJeremy Linton
There is a lock protecting the trace_enum_map, rename it to reflect the use by more than enums. Link: http://lkml.kernel.org/r/20170531215653.3240-6-jeremy.linton@arm.com Signed-off-by: Jeremy Linton <jeremy.linton@arm.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-06-13trace: rename trace enum data structures in trace.cJeremy Linton
The enum map entries can be exported to userspace via a sys enum_map file. Rename those functions and structures to reflect the fact that we are using them for more than enums. Link: http://lkml.kernel.org/r/20170531215653.3240-5-jeremy.linton@arm.com Signed-off-by: Jeremy Linton <jeremy.linton@arm.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-06-13trace: rename struct module entry for trace enumsJeremy Linton
Each module has a list of enum's its contributing to the enum map, rename that entry to reflect its use by more than enums. Link: http://lkml.kernel.org/r/20170531215653.3240-4-jeremy.linton@arm.com Signed-off-by: Jeremy Linton <jeremy.linton@arm.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-06-13trace: rename trace_enum_map to trace_eval_mapJeremy Linton
Each enum is loaded into the trace_enum_map, as we are now using this for more than enums rename it. Link: http://lkml.kernel.org/r/20170531215653.3240-3-jeremy.linton@arm.com Signed-off-by: Jeremy Linton <jeremy.linton@arm.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-06-13trace: rename kernel enum section to evalJeremy Linton
The kernel and its modules have sections containing the enum string to value conversions. Rename this section because we intend to store more than enums in it. Link: http://lkml.kernel.org/r/20170531215653.3240-2-jeremy.linton@arm.com Signed-off-by: Jeremy Linton <jeremy.linton@arm.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-06-13tracing: Remove unused declaration of trace_stop_cmdline_recordingJoel Fernandes
trace_stop_cmdline_recording declaration isn't in use, remove it. Link: http://lkml.kernel.org/r/20170609025327.9508-2-joelaf@google.com Cc: kernel-team@android.com Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by: Joel Fernandes <joelaf@google.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>