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2019-11-20ftrace: Return ENOTSUPP when DYNAMIC_FTRACE_WITH_DIRECT_CALLS is not configuredAlexei Starovoitov
When CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS is not set it's best to have the stub functions return ENOTSUPP instead of ENODEV, otherwise ENODEV is a valid error when ip is incorrect which is indistinguishable from ftrace not compiled in. Link: http://lkml.kernel.org/r/CAADnVQ+OzTikM9EhrfsC7NFsVYhATW1SVHxK64w3xn9qpk81pg@mail.gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-18ftrace: Rename ftrace_graph_stub to ftrace_stub_graphSteven Rostedt (VMware)
The ftrace_graph_stub was created and points to ftrace_stub as a way to assign the functon graph tracer function pointer to a stub function with a different prototype than what ftrace_stub has and not trigger the C verifier. The ftrace_graph_stub was created via the linker script vmlinux.lds.h. Unfortunately, powerpc already uses the name ftrace_graph_stub for its internal implementation of the function graph tracer, and even though powerpc would still build, the change via the linker script broke function tracer on powerpc from working. By using the name ftrace_stub_graph, which does not exist anywhere else in the kernel, this should not be a problem. Link: https://lore.kernel.org/r/1573849732.5937.136.camel@lca.pw Fixes: b83b43ffc6e4 ("fgraph: Fix function type mismatches of ftrace_graph_return using ftrace_stub") Reorted-by: Qian Cai <cai@lca.pw> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-18ftrace: Add a helper function to modify_ftrace_direct() to allow arch ↵Steven Rostedt (VMware)
optimization If a direct ftrace callback is at a location that does not have any other ftrace helpers attached to it, it is possible to simply just change the text to call the new caller (if the architecture supports it). But this requires special architecture code. Currently, modify_ftrace_direct() uses a trick to add a stub ftrace callback to the location forcing it to call the ftrace iterator. Then it can change the direct helper to call the new function in C, and then remove the stub. Removing the stub will have the location now call the new location that the direct helper is using. The new helper function does the registering the stub trick, but is a weak function, allowing an architecture to override it to do something a bit more direct. Link: https://lore.kernel.org/r/20191115215125.mbqv7taqnx376yed@ast-mbp.dhcp.thefacebook.com Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-15ftrace: Add helper find_direct_entry() to consolidate codeSteven Rostedt (VMware)
Both unregister_ftrace_direct() and modify_ftrace_direct() needs to normalize the ip passed in to match the rec->ip, as it is acceptable to have the ip on the ftrace call site but not the start. There are also common validity checks with the record found by the ip, these should be done for both unregister_ftrace_direct() and modify_ftrace_direct(). Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-15ftrace: Add another check for match in register_ftrace_direct()Steven Rostedt (VMware)
As an instruction pointer passed into register_ftrace_direct() may just exist on the ftrace call site, but may not be the start of the call site itself, register_ftrace_direct() still needs to update test if a direct call exists on the normalized site, as only one direct call is allowed at any one time. Fixes: 763e34e74bb7d ("ftrace: Add register_ftrace_direct()") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-15ftrace: Fix accounting bug with direct->count in register_ftrace_direct()Steven Rostedt (VMware)
The direct->count wasn't being updated properly, where it only was updated when the first entry was added, but should be updated every time. Fixes: 013bf0da04748 ("ftrace: Add ftrace_find_direct_func()") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-15ftrace/selftests: Fix spelling mistake "wakeing" -> "waking"Colin Ian King
There is a spelling mistake in a trace_printk message. As well as in the selftests that search for this string. Link: http://lkml.kernel.org/r/20191115085938.38947-1-colin.king@canonical.com Link: http://lkml.kernel.org/r/20191115090356.39572-1-colin.king@canonical.com Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-15tracing: Increase SYNTH_FIELDS_MAX for synthetic_eventsArtem Bityutskiy
Increase the maximum allowed count of synthetic event fields from 16 to 32 in order to allow for larger-than-usual events. Link: http://lkml.kernel.org/r/20191115091730.9192-1-dedekind1@gmail.com Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-14ftrace/samples: Add a sample module that implements modify_ftrace_direct()Steven Rostedt (VMware)
Add a sample module that tests modify_ftrace_direct(), and this can be used by the selftests as well. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-14ftrace: Add modify_ftrace_direct()Steven Rostedt (VMware)
Add a new function modify_ftrace_direct() that will allow a user to update an existing direct caller to a new trampoline, without missing hits due to unregistering one and then adding another. Link: https://lore.kernel.org/r/20191109022907.6zzo6orhxpt5n2sv@ast-mbp.dhcp.thefacebook.com Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-14tracing: Add missing "inline" in stub function of latency_fsnotify()Steven Rostedt (VMware)
The latency_fsnotify() stub when the function is not defined, was missing the "inline". Link: https://lore.kernel.org/r/20191115140213.74c5efe7@canb.auug.org.au Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-14tracing: Remove stray tab in TRACE_EVAL_MAP_FILE's help textBorislav Petkov
There was a stray tab in the help text of the aforementioned config option which showed like this: The "print fmt" of the trace events will show the enum/sizeof names instead of their values. This can cause problems for user space tools ... in menuconfig. Remove it and end a sentence with a fullstop. No functional changes. Link: http://lkml.kernel.org/r/20191112174219.10933-1-bp@alien8.de Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-14tracing: Use seq_buf_hex_dump() to dump buffersPiotr Maziarz
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>
2019-11-14seq_buf: Add printing formatted hex dumpsPiotr Maziarz
Provided function is an analogue of print_hex_dump(). Implementing this function in seq_buf allows using for multiple purposes (e.g. for tracing) and therefore prevents from code duplication in every layer that uses seq_buf. print_hex_dump() is an essential part of logging data to dmesg. Adding similar capability for other purposes is beneficial to all users. Example usage: seq_buf_hex_dump(seq, "", DUMP_PREFIX_OFFSET, 16, 4, buf, ARRAY_SIZE(buf), true); Example output: 00000000: 00000000 ffffff10 ffffff32 ffff3210 ........2....2.. 00000010: ffff3210 83d00437 c0700000 00000000 .2..7.....p..... 00000020: 02010004 0000000f 0000000f 00004002 .............@.. 00000030: 00000fff 00000000 ........ Link: http://lkml.kernel.org/r/1573130738-29390-1-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>
2019-11-14tracing/kprobe: Check whether the non-suffixed symbol is notraceMasami Hiramatsu
Check whether the non-suffixed symbol is notrace, since suffixed symbols are generated by the compilers for optimization. Based on these suffixed symbols, notrace check might not work because some of them are just a partial code of the original function. (e.g. cold-cache (unlikely) code is separated from original function as FUNCTION.cold.XX) For example, without this fix, # echo p device_add.cold.67 > /sys/kernel/debug/tracing/kprobe_events sh: write error: Invalid argument # cat /sys/kernel/debug/tracing/error_log [ 135.491035] trace_kprobe: error: Failed to register probe event Command: p device_add.cold.67 ^ # dmesg | tail -n 1 [ 135.488599] trace_kprobe: Could not probe notrace function device_add.cold.67 With this, # echo p device_add.cold.66 > /sys/kernel/debug/tracing/kprobe_events # cat /sys/kernel/debug/kprobes/list ffffffff81599de9 k device_add.cold.66+0x0 [DISABLED] Actually, kprobe blacklist already did similar thing, see within_kprobe_blacklist(). Link: http://lkml.kernel.org/r/157233790394.6706.18243942030937189679.stgit@devnote2 Fixes: 45408c4f9250 ("tracing: kprobes: Prohibit probing on notrace function") Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-14tracing: use kvcalloc for tgid_map array allocationYuming Han
Fail to allocate memory for tgid_map, because it requires order-6 page. detail as: c3 sh: page allocation failure: order:6, mode:0x140c0c0(GFP_KERNEL), nodemask=(null) c3 sh cpuset=/ mems_allowed=0 c3 CPU: 3 PID: 5632 Comm: sh Tainted: G W O 4.14.133+ #10 c3 Hardware name: Generic DT based system c3 Backtrace: c3 [<c010bdbc>] (dump_backtrace) from [<c010c08c>](show_stack+0x18/0x1c) c3 [<c010c074>] (show_stack) from [<c0993c54>](dump_stack+0x84/0xa4) c3 [<c0993bd0>] (dump_stack) from [<c0229858>](warn_alloc+0xc4/0x19c) c3 [<c0229798>] (warn_alloc) from [<c022a6e4>](__alloc_pages_nodemask+0xd18/0xf28) c3 [<c02299cc>] (__alloc_pages_nodemask) from [<c0248344>](kmalloc_order+0x20/0x38) c3 [<c0248324>] (kmalloc_order) from [<c0248380>](kmalloc_order_trace+0x24/0x108) c3 [<c024835c>] (kmalloc_order_trace) from [<c01e6078>](set_tracer_flag+0xb0/0x158) c3 [<c01e5fc8>] (set_tracer_flag) from [<c01e6404>](trace_options_core_write+0x7c/0xcc) c3 [<c01e6388>] (trace_options_core_write) from [<c0278b1c>](__vfs_write+0x40/0x14c) c3 [<c0278adc>] (__vfs_write) from [<c0278e10>](vfs_write+0xc4/0x198) c3 [<c0278d4c>] (vfs_write) from [<c027906c>](SyS_write+0x6c/0xd0) c3 [<c0279000>] (SyS_write) from [<c01079a0>](ret_fast_syscall+0x0/0x54) Switch to use kvcalloc to avoid unexpected allocation failures. Link: http://lkml.kernel.org/r/1571888070-24425-1-git-send-email-chunyan.zhang@unisoc.com Signed-off-by: Yuming Han <yuming.han@unisoc.com> Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-14tracing/hwlat: Fix a few trivial nitsSrivatsa S. Bhat (VMware)
Update the source file name in the comments, and fix a grammatical error. Link: http://lkml.kernel.org/r/157073346821.17189.8946944856026592247.stgit@srivatsa-ubuntu Signed-off-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-14tracing: Use generic type for comparator functionAndy Shevchenko
Comparator function type, cmp_func_t, is defined in the types.h, use it in the code. Link: http://lkml.kernel.org/r/20191007135656.37734-3-andriy.shevchenko@linux.intel.com Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-14lib/bsearch: Use generic type for comparator functionAndy Shevchenko
Comparator function type, cmp_func_t, is defined in the types.h, use it in bsearch() and, thus, add more sense to the corresponding comment in the code. Link: http://lkml.kernel.org/r/20191007135656.37734-2-andriy.shevchenko@linux.intel.com Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-14lib/sort: Move swap, cmp and cmp_r function types for wider useAndy Shevchenko
The function types for swap, cmp and cmp_r functions are already being in use by modules. Move them to types.h that everybody in kernel will be able to use generic types instead of custom ones. This adds more sense to the comment in bsearch() later on. Link: http://lkml.kernel.org/r/20191007135656.37734-1-andriy.shevchenko@linux.intel.com Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-14tracing/selftests: Turn off timeout settingSteven Rostedt (VMware)
As the ftrace selftests can run for a long period of time, disable the timeout that the general selftests have. If a selftest hangs, then it probably means the machine will hang too. Link: https://lore.kernel.org/r/alpine.LSU.2.21.1911131604170.18679@pobox.suse.cz Suggested-by: Miroslav Benes <mbenes@suse.cz> Tested-by: Miroslav Benes <mbenes@suse.cz> Reviewed-by: Miroslav Benes <mbenes@suse.cz> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-14fgraph: Fix function type mismatches of ftrace_graph_return using ftrace_stubSteven Rostedt (VMware)
The C compiler is allowing more checks to make sure that function pointers are assigned to the correct prototype function. Unfortunately, the function graph tracer uses a special name with its assigned ftrace_graph_return function pointer that maps to a stub function used by the function tracer (ftrace_stub). The ftrace_graph_return variable is compared to the ftrace_stub in some archs to know if the function graph tracer is enabled or not. This means we can not just simply create a new function stub that compares it without modifying all the archs. Instead, have the linker script create a function_graph_stub that maps to ftrace_stub, and this way we can define the prototype for it to match the prototype of ftrace_graph_return, and make the compiler checks all happy! Link: http://lkml.kernel.org/r/20191015090055.789a0aed@gandalf.local.home Cc: linux-sh@vger.kernel.org Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Rich Felker <dalias@libc.org> Reported-by: Sami Tolvanen <samitolvanen@google.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13tracing: Adding NULL checks for trace_array descriptor pointerDivya Indi
As part of commit f45d1225adb0 ("tracing: Kernel access to Ftrace instances") we exported certain functions. Here, we are adding some additional NULL checks to ensure safe usage by users of these APIs. Link: http://lkml.kernel.org/r/1565805327-579-4-git-send-email-divya.indi@oracle.com Signed-off-by: Divya Indi <divya.indi@oracle.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13tracing: Verify if trace array exists before destroying it.Divya Indi
A trace array can be destroyed from userspace or kernel. Verify if the trace array exists before proceeding to destroy/remove it. Link: http://lkml.kernel.org/r/1565805327-579-3-git-send-email-divya.indi@oracle.com Reviewed-by: Aruna Ramakrishna <aruna.ramakrishna@oracle.com> Signed-off-by: Divya Indi <divya.indi@oracle.com> [ Removed unneeded braces ] Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13tracing: Declare newly exported APIs in include/linux/trace.hDivya Indi
Declare the newly introduced and exported APIs in the header file - include/linux/trace.h. Moving previous declarations from kernel/trace/trace.h to include/linux/trace.h. Link: http://lkml.kernel.org/r/1565805327-579-2-git-send-email-divya.indi@oracle.com Signed-off-by: Divya Indi <divya.indi@oracle.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13tracing: Make internal ftrace events staticBen Dooks
The event_class_ftrace_##call and event_##call do not seem to be used outside of trace_export.c so make them both static to avoid a number of sparse warnings: kernel/trace/trace_entries.h:59:1: warning: symbol 'event_class_ftrace_function' was not declared. Should it be static? kernel/trace/trace_entries.h:59:1: warning: symbol '__event_function' was not declared. Should it be static? kernel/trace/trace_entries.h:77:1: warning: symbol 'event_class_ftrace_funcgraph_entry' was not declared. Should it be static? kernel/trace/trace_entries.h:77:1: warning: symbol '__event_funcgraph_entry' was not declared. Should it be static? kernel/trace/trace_entries.h:93:1: warning: symbol 'event_class_ftrace_funcgraph_exit' was not declared. Should it be static? kernel/trace/trace_entries.h:93:1: warning: symbol '__event_funcgraph_exit' was not declared. Should it be static? kernel/trace/trace_entries.h:129:1: warning: symbol 'event_class_ftrace_context_switch' was not declared. Should it be static? kernel/trace/trace_entries.h:129:1: warning: symbol '__event_context_switch' was not declared. Should it be static? kernel/trace/trace_entries.h:149:1: warning: symbol 'event_class_ftrace_wakeup' was not declared. Should it be static? kernel/trace/trace_entries.h:149:1: warning: symbol '__event_wakeup' was not declared. Should it be static? kernel/trace/trace_entries.h:171:1: warning: symbol 'event_class_ftrace_kernel_stack' was not declared. Should it be static? kernel/trace/trace_entries.h:171:1: warning: symbol '__event_kernel_stack' was not declared. Should it be static? kernel/trace/trace_entries.h:191:1: warning: symbol 'event_class_ftrace_user_stack' was not declared. Should it be static? kernel/trace/trace_entries.h:191:1: warning: symbol '__event_user_stack' was not declared. Should it be static? kernel/trace/trace_entries.h:214:1: warning: symbol 'event_class_ftrace_bprint' was not declared. Should it be static? kernel/trace/trace_entries.h:214:1: warning: symbol '__event_bprint' was not declared. Should it be static? kernel/trace/trace_entries.h:230:1: warning: symbol 'event_class_ftrace_print' was not declared. Should it be static? kernel/trace/trace_entries.h:230:1: warning: symbol '__event_print' was not declared. Should it be static? kernel/trace/trace_entries.h:247:1: warning: symbol 'event_class_ftrace_raw_data' was not declared. Should it be static? kernel/trace/trace_entries.h:247:1: warning: symbol '__event_raw_data' was not declared. Should it be static? kernel/trace/trace_entries.h:262:1: warning: symbol 'event_class_ftrace_bputs' was not declared. Should it be static? kernel/trace/trace_entries.h:262:1: warning: symbol '__event_bputs' was not declared. Should it be static? kernel/trace/trace_entries.h:277:1: warning: symbol 'event_class_ftrace_mmiotrace_rw' was not declared. Should it be static? kernel/trace/trace_entries.h:277:1: warning: symbol '__event_mmiotrace_rw' was not declared. Should it be static? kernel/trace/trace_entries.h:298:1: warning: symbol 'event_class_ftrace_mmiotrace_map' was not declared. Should it be static? kernel/trace/trace_entries.h:298:1: warning: symbol '__event_mmiotrace_map' was not declared. Should it be static? kernel/trace/trace_entries.h:322:1: warning: symbol 'event_class_ftrace_branch' was not declared. Should it be static? kernel/trace/trace_entries.h:322:1: warning: symbol '__event_branch' was not declared. Should it be static? kernel/trace/trace_entries.h:343:1: warning: symbol 'event_class_ftrace_hwlat' was not declared. Should it be static? kernel/trace/trace_entries.h:343:1: warning: symbol '__event_hwlat' was not declared. Should it be static? Link: http://lkml.kernel.org/r/20191015121012.18824-1-ben.dooks@codethink.co.uk Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13tracing: Use CONFIG_PREEMPTIONSebastian Andrzej Siewior
CONFIG_PREEMPTION is selected by CONFIG_PREEMPT and by CONFIG_PREEMPT_RT. Both PREEMPT and PREEMPT_RT require the same functionality which today depends on CONFIG_PREEMPT. Add additional header output for PREEMPT_RT. Link: http://lkml.kernel.org/r/20191015191821.11479-34-bigeasy@linutronix.de Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13preemptirq_delay_test: Add the burst feature and a sysfs triggerViktor Rosendahl (BMW)
This burst feature enables the user to generate a burst of preempt/irqsoff latencies. This makes it possible to test whether we are able to detect latencies that systematically occur very close to each other. The maximum burst size is 10. We also create 10 identical test functions, so that we get 10 different backtraces; this is useful when we want to test whether we can detect all the latencies in a burst. Otherwise, there would be no easy way of differentiating between which latency in a burst was captured by the tracer. In addition, there is a sysfs trigger, so that it's not necessary to reload the module to repeat the test. The trigger will appear as /sys/kernel/preemptirq_delay_test/trigger in sysfs. Link: http://lkml.kernel.org/r/20191008220824.7911-3-viktor.rosendahl@gmail.com Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Viktor Rosendahl (BMW) <viktor.rosendahl@gmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13ftrace: Implement fs notification for tracing_max_latencyViktor Rosendahl (BMW)
This patch implements the feature that the tracing_max_latency file, e.g. /sys/kernel/debug/tracing/tracing_max_latency will receive notifications through the fsnotify framework when a new latency is available. One particularly interesting use of this facility is when enabling threshold tracing, through /sys/kernel/debug/tracing/tracing_thresh, together with the preempt/irqsoff tracers. This makes it possible to implement a user space program that can, with equal probability, obtain traces of latencies that occur immediately after each other in spite of the fact that the preempt/irqsoff tracers operate in overwrite mode. This facility works with the hwlat, preempt/irqsoff, and wakeup tracers. The tracers may call the latency_fsnotify() from places such as __schedule() or do_idle(); this makes it impossible to call queue_work() directly without risking a deadlock. The same would happen with a softirq, kernel thread or tasklet. For this reason we use the irq_work mechanism to call queue_work(). This patch creates a new workqueue. The reason for doing this is that I wanted to use the WQ_UNBOUND and WQ_HIGHPRI flags. My thinking was that WQ_UNBOUND might help with the latency in some important cases. If we use: queue_work(system_highpri_wq, &tr->fsnotify_work); then the work will (almost) always execute on the same CPU but if we are unlucky that CPU could be too busy while there could be another CPU in the system that would be able to process the work soon enough. queue_work_on() could be used to queue the work on another CPU but it seems difficult to select the right CPU. Link: http://lkml.kernel.org/r/20191008220824.7911-2-viktor.rosendahl@gmail.com Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Viktor Rosendahl (BMW) <viktor.rosendahl@gmail.com> [ Added max() to have one compare for max latency ] Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13ftrace: Add information on number of page groups allocatedSteven Rostedt (VMware)
Looking for ways to shrink the size of the dyn_ftrace structure, knowing the information about how many pages and the number of groups of those pages, is useful in working out the best ways to save on memory. This adds one info print on how many groups of pages were used to allocate the ftrace dyn_ftrace structures, and also shows the number of pages and groups in the dyn_ftrace_total_info (which is used for debugging). Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13ftrace/x86: Tell objtool to ignore nondeterministic ftrace stack layoutJosh Poimboeuf
Objtool complains about the new ftrace direct trampoline code: arch/x86/kernel/ftrace_64.o: warning: objtool: ftrace_regs_caller()+0x190: stack state mismatch: cfa1=7+16 cfa2=7+24 Typically, code has a deterministic stack layout, such that at a given instruction address, the stack frame size is always the same. That's not the case for the new ftrace_regs_caller() code after it adjusts the stack for the direct case. Just plead ignorance and assume it's always the non-direct path. Note this creates a tiny window for ORC to get confused. Link: http://lkml.kernel.org/r/20191108225100.ea3bhsbdf6oerj6g@treble Reported-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13ftrace/x86: Add a counter to test function_graph with directSteven Rostedt (VMware)
As testing for direct calls from the function graph tracer adds a little overhead (which is a lot when tracing every function), add a counter that can be used to test if function_graph tracer needs to test for a direct caller or not. It would have been nicer if we could use a static branch, but the static branch logic fails when used within the function graph tracer trampoline. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13ftrace/x86: Add register_ftrace_direct() for custom trampolinesSteven Rostedt (VMware)
Enable x86 to allow for register_ftrace_direct(), where a custom trampoline may be called directly from an ftrace mcount/fentry location. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13ftrace/selftests: Update the direct call selftests to test two direct callsSteven Rostedt (VMware)
The register_ftrace_direct() takes a different path if there's already a direct call registered, but this was not tested in the self tests. Now that there's a second direct caller test module, we can use this to test not only one direct caller, but two. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13ftrace: Add another example of register_ftrace_direct() use caseSteven Rostedt (VMware)
Add another module sample that registers a direct trampoline to a function via register_ftrace_direct(). Having another module that does this allows to test the use case of multiple direct callers registered, as more than one direct caller goes into another path, and is needed to perform proper testing of the register_ftrace_direct() call. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13ftrace/selftest: Add tests to test register_ftrace_direct()Steven Rostedt (VMware)
Add two test cases that test the new ftrace direct functionality if the ftrace-direct sample module is available. One test case tests against each available tracer (function, function_graph, mmiotrace, etc), and the other test tests against a kprobe at the same location as the direct caller. Both tests follow the same pattern of testing combinations: enable test (either the tracer or the kprobe) load direct function module unload direct function module disable test enable test load direct function module disable test unload direct function module load direct function module enable test disable test unload direct function module load direct function module enable test unload direct function module disable test As most the bugs in development happened with various ways of enabling or disabling the direct calls with function tracer in one of these combinations. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13ftrace: Add sample module that uses register_ftrace_direct()Steven Rostedt (VMware)
Add a sample module that shows a simple use case for regsiter_ftrace_direct(), and how to use it. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13ftrace: Add ftrace_find_direct_func()Steven Rostedt (VMware)
As function_graph tracer modifies the return address to insert a trampoline to trace the return of a function, it must be aware of a direct caller, as when it gets called, the function's return address may not be at on the stack where it expects. It may have to see if that return address points to the a direct caller and adjust if it is. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13ftrace: Add register_ftrace_direct()Steven Rostedt (VMware)
Add the start of the functionality to allow other trampolines to use the ftrace mcount/fentry/nop location. This adds two new functions: register_ftrace_direct() and unregister_ftrace_direct() Both take two parameters: the first is the instruction address of where the mcount/fentry/nop exists, and the second is the trampoline to have that location called. This will handle cases where ftrace is already used on that same location, and will make it still work, where the registered direct called trampoline will get called after all the registered ftrace callers are handled. Currently, it will not allow for IP_MODIFY functions to be called at the same locations, which include some kprobes and live kernel patching. At this point, no architecture supports this. This is only the start of implementing the framework. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-08ftrace: Separate out functionality from ftrace_location_range()Steven Rostedt (VMware)
Create a new function called lookup_rec() from the functionality of ftrace_location_range(). The difference between lookup_rec() is that it returns the record that it finds, where as ftrace_location_range() returns only if it found a match or not. The lookup_rec() is static, and can be used for new functionality where ftrace needs to find a record of a specific address. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-08ftrace: Separate out the copying of a ftrace_hash from __ftrace_hash_move()Steven Rostedt (VMware)
Most of the functionality of __ftrace_hash_move() can be reused, but not all of it. That is, __ftrace_hash_move() is used to simply make a new hash from an existing one, using the same size as the original. Creating a dup_hash(), where we can specify a new size will be useful when we want to create a hash with a default size, or simply copy the old one. Signed-off-by: Steven Rostedt (VMWare) <rostedt@goodmis.org>
2019-11-04selftests/livepatch: Test interaction with ftrace_enabledJoe Lawrence
Since livepatching depends upon ftrace handlers to implement "patched" code functionality, verify that the ftrace_enabled sysctl value interacts with livepatch registration as expected. At the same time, ensure that ftrace_enabled is set and part of the test environment configuration that is saved and restored when running the selftests. Link: http://lkml.kernel.org/r/20191016113316.13415-4-mbenes@suse.cz Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Miroslav Benes <mbenes@suse.cz> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-04selftests/livepatch: Make dynamic debug setup and restore genericJoe Lawrence
Livepatch selftests currently save the current dynamic debug config and tweak it for the selftests. The config is restored at the end. Make the infrastructure generic, so that more variables can be saved and restored. Link: http://lkml.kernel.org/r/20191016113316.13415-3-mbenes@suse.cz Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Miroslav Benes <mbenes@suse.cz> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-04ftrace: Introduce PERMANENT ftrace_ops flagMiroslav Benes
Livepatch uses ftrace for redirection to new patched functions. It means that if ftrace is disabled, all live patched functions are disabled as well. Toggling global 'ftrace_enabled' sysctl thus affect it directly. It is not a problem per se, because only administrator can set sysctl values, but it still may be surprising. Introduce PERMANENT ftrace_ops flag to amend this. If the FTRACE_OPS_FL_PERMANENT is set on any ftrace ops, the tracing cannot be disabled by disabling ftrace_enabled. Equally, a callback with the flag set cannot be registered if ftrace_enabled is disabled. Link: http://lkml.kernel.org/r/20191016113316.13415-2-mbenes@suse.cz Reviewed-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> Signed-off-by: Miroslav Benes <mbenes@suse.cz> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-03Linux 5.4-rc6v5.4-rc6Linus Torvalds
2019-11-03Merge tag 'usb-5.4-rc6' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb Pull USB fixes from Greg KH: "The USB sub-maintainers woke up this past week and sent a bunch of tiny fixes. Here are a lot of small patches that that resolve a bunch of reported issues in the USB core, drivers, serial drivers, gadget drivers, and of course, xhci :) All of these have been in linux-next with no reported issues" * tag 'usb-5.4-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (31 commits) usb: dwc3: gadget: fix race when disabling ep with cancelled xfers usb: cdns3: gadget: Fix g_audio use case when connected to Super-Speed host usb: cdns3: gadget: reset EP_CLAIMED flag while unloading USB: serial: whiteheat: fix line-speed endianness USB: serial: whiteheat: fix potential slab corruption USB: gadget: Reject endpoints with 0 maxpacket value UAS: Revert commit 3ae62a42090f ("UAS: fix alignment of scatter/gather segments") usb-storage: Revert commit 747668dbc061 ("usb-storage: Set virt_boundary_mask to avoid SG overflows") usbip: Fix free of unallocated memory in vhci tx usbip: tools: Fix read_usb_vudc_device() error path handling usb: xhci: fix __le32/__le64 accessors in debugfs code usb: xhci: fix Immediate Data Transfer endianness xhci: Fix use-after-free regression in xhci clear hub TT implementation USB: ldusb: fix control-message timeout USB: ldusb: use unsigned size format specifiers USB: ldusb: fix ring-buffer locking USB: Skip endpoints with 0 maxpacket length usb: cdns3: gadget: Don't manage pullups usb: dwc3: remove the call trace of USBx_GFLADJ usb: gadget: configfs: fix concurrent issue between composite APIs ...
2019-11-02Merge tag '5.4-rc6-smb3-fix' of git://git.samba.org/sfrench/cifs-2.6Linus Torvalds
Pull cifs fix from Steve French: "A small smb3 memleak fix" * tag '5.4-rc6-smb3-fix' of git://git.samba.org/sfrench/cifs-2.6: fix memory leak in large read decrypt offload
2019-11-02Merge tag 'hwmon-for-v5.4-rc6' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging Pull hwmon fixes from Guenter Roeck: - Fix read timeout problem in ina3221 driver - Fix wrong bitmask in nct7904 driver * tag 'hwmon-for-v5.4-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging: hwmon: (ina3221) Fix read timeout issue hwmon: (nct7904) Fix the incorrect value of vsen_mask & tcpu_mask & temp_mode in nct7904_data struct.
2019-11-02Merge tag 'pwm/for-5.4-rc6' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm Pull pwm fixes from Thierry Reding: "It turned out that relying solely on drivers storing all the PWM state in hardware was a little premature and causes a number of subtle (and some not so subtle) regressions. Revert the offending patch for now" * tag 'pwm/for-5.4-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm: Revert "pwm: Let pwm_get_state() return the last implemented state"
2019-11-02Merge tag 'scsi-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi Pull SCSI fixes from James Bottomley: "Nine changes, eight in drivers [ufs, target, lpfc x 2, qla2xxx x 4] and one core change in sd that fixes an I/O failure on DIF type 3 devices" * tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: scsi: qla2xxx: stop timer in shutdown path scsi: sd: define variable dif as unsigned int instead of bool scsi: target: cxgbit: Fix cxgbit_fw4_ack() scsi: qla2xxx: Fix partial flash write of MBI scsi: qla2xxx: Initialized mailbox to prevent driver load failure scsi: lpfc: Honor module parameter lpfc_use_adisc scsi: ufs-bsg: Wake the device before sending raw upiu commands scsi: lpfc: Check queue pointer before use scsi: qla2xxx: fixup incorrect usage of host_byte