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* Merge tag 'for-linus-20181102' of git://git.kernel.dk/linux-blockLinus Torvalds2018-11-021-2/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull block layer fixes from Jens Axboe: "The biggest part of this pull request is the revert of the blkcg cleanup series. It had one fix earlier for a stacked device issue, but another one was reported. Rather than play whack-a-mole with this, revert the entire series and try again for the next kernel release. Apart from that, only small fixes/changes. Summary: - Indentation fixup for mtip32xx (Colin Ian King) - The blkcg cleanup series revert (Dennis Zhou) - Two NVMe fixes. One fixing a regression in the nvme request initialization in this merge window, causing nvme-fc to not work. The other is a suspend/resume p2p resource issue (James, Keith) - Fix sg discard merge, allowing us to merge in cases where we didn't before (Jianchao Wang) - Call rq_qos_exit() after the queue is frozen, preventing a hang (Ming) - Fix brd queue setup, fixing an oops if we fail setting up all devices (Ming)" * tag 'for-linus-20181102' of git://git.kernel.dk/linux-block: nvme-pci: fix conflicting p2p resource adds nvme-fc: fix request private initialization blkcg: revert blkcg cleanups series block: brd: associate with queue until adding disk block: call rq_qos_exit() after queue is frozen mtip32xx: clean an indentation issue, remove extraneous tabs block: fix the DISCARD request merge
| * blkcg: revert blkcg cleanups seriesDennis Zhou2018-11-021-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This reverts a series committed earlier due to null pointer exception bug report in [1]. It seems there are edge case interactions that I did not consider and will need some time to understand what causes the adverse interactions. The original series can be found in [2] with a follow up series in [3]. [1] https://www.spinics.net/lists/cgroups/msg20719.html [2] https://lore.kernel.org/lkml/20180911184137.35897-1-dennisszhou@gmail.com/ [3] https://lore.kernel.org/lkml/20181020185612.51587-1-dennis@kernel.org/ This reverts the following commits: d459d853c2ed, b2c3fa546705, 101246ec02b5, b3b9f24f5fcc, e2b0989954ae, f0fcb3ec89f3, c839e7a03f92, bdc2491708c4, 74b7c02a9bc1, 5bf9a1f3b4ef, a7b39b4e961c, 07b05bcc3213, 49f4c2dc2b50, 27e6fa996c53 Signed-off-by: Dennis Zhou <dennis@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | Merge tag 'platform-drivers-x86-v4.20-1' of ↵Linus Torvalds2018-11-011-1/+1
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.infradead.org/linux-platform-drivers-x86 Pull x86 platform driver updates from Darren Hart: - Move the Dell dcdbas and dell_rbu drivers into platform/drivers/x86 as they are closely coupled with other drivers in this location. - Improve _init* usage for acerhdf and fix some usage issues with messages and module parameters. - Simplify asus-wmi by calling ACPI/WMI methods directly, eliminating workqueue overhead, eliminate double reporting of keyboard backlight. - Fix wake from USB failure on Bay Trail devices (intel_int0002_vgpio). - Notify intel_telemetry users when IPC1 device is not enabled. - Update various drivers with new laptop model IDs. - Update several intel drivers to use SPDX identifers and order headers alphabetically. * tag 'platform-drivers-x86-v4.20-1' of git://git.infradead.org/linux-platform-drivers-x86: (64 commits) HID: asus: only support backlight when it's not driven by WMI platform/x86: asus-wmi: export function for evaluating WMI methods platform/x86: asus-wmi: Only notify kbd LED hw_change by fn-key pressed platform/x86: wmi: declare device_type structure as constant platform/x86: ideapad: Add Y530-15ICH to no_hw_rfkill platform/x86: Add Intel AtomISP2 dummy / power-management driver platform/x86: touchscreen_dmi: Add min-x and min-y settings for various models platform/x86: touchscreen_dmi: Add info for the Onda V80 Plus v3 tablet platform/x86: touchscreen_dmi: Add info for the Trekstor Primetab T13B tablet platform/x86: intel_telemetry: Get rid of custom macro platform/x86: intel_telemetry: report debugfs failure MAINTAINERS: intel_telemetry: Update maintainers info platform/x86: Add LG Gram laptop special features driver platform/x86: asus-wmi: Simplify the keyboard brightness updating process platform/x86: touchscreen_dmi: Add info for the Trekstor Primebook C11 convertible platform/x86: mlx-platform: Properly use mlxplat_mlxcpld_msn201x_items MAINTAINERS: intel_pmc_core: Update MAINTAINERS firmware: dcdbas: include linux/io.h platform/x86: intel-wmi-thunderbolt: Add dynamic debugging platform/x86: intel-wmi-thunderbolt: Convert to use SPDX identifier ...
| * | tracing: Trivia spelling fix containerof() -> container_of()Andy Shevchenko2018-09-261-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | This is the only location on kernel that has wrong spelling of the container_of() helper. Fix it. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
* | | Merge tag 'trace-v4.20' of ↵Linus Torvalds2018-10-308-914/+951
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: "The biggest change here is the updates to kprobes Back in January I posted patches to create function based events. These were the events that you suggested I make to allow developers to easily create events in code where no trace event exists. After posting those changes for review, it was suggested that we implement this instead with kprobes. The problem with kprobes is that the interface is too complex and needs to be simplified. Masami Hiramatsu posted patches in March and I've been playing with them a bit. There's been a bit of clean up in the kprobe code that was inspired by the function based event patches, and a couple of enhancements to the kprobe event interface. - If the arch supports it (we added support for x86), you can place a kprobe event at the start of a function and use $arg1, $arg2, etc to reference the arguments of a function. (Before you needed to know what register or where on the stack the argument was). - The second is a way to see array of events. For example, if you reference a mac address, you can add: echo 'p:mac ip_rcv perm_addr=+574($arg2):x8[6]' > kprobe_events And this will produce: mac: (ip_rcv+0x0/0x140) perm_addr={0x52,0x54,0x0,0xc0,0x76,0xec} Other changes include - Exporting trace_dump_stack to modules - Have the stack tracer trace the entire stack (stop trying to remove tracing itself, as we keep removing too much). - Added support for SDT in uprobes" [ SDT - "Statically Defined Tracing" are userspace markers for tracing. Let's not use random TLA's in explanations unless they are fairly well-established as generic (at least for kernel people) - Linus ] * tag 'trace-v4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (24 commits) tracing: Have stack tracer trace full stack tracing: Export trace_dump_stack to modules tracing: probeevent: Fix uninitialized used of offset in parse args tracing/kprobes: Allow kprobe-events to record module symbol tracing/kprobes: Check the probe on unloaded module correctly tracing/uprobes: Fix to return -EFAULT if copy_from_user failed tracing: probeevent: Add $argN for accessing function args x86: ptrace: Add function argument access API tracing: probeevent: Add array type support tracing: probeevent: Add symbol type tracing: probeevent: Unify fetch_insn processing common part tracing: probeevent: Append traceprobe_ for exported function tracing: probeevent: Return consumed bytes of dynamic area tracing: probeevent: Unify fetch type tables tracing: probeevent: Introduce new argument fetching code tracing: probeevent: Remove NOKPROBE_SYMBOL from print functions tracing: probeevent: Cleanup argument field definition tracing: probeevent: Cleanup print argument functions trace_uprobe: support reference counter in fd-based uprobe perf probe: Support SDT markers having reference counter (semaphore) ...
| * | | tracing: Have stack tracer trace full stackSteven Rostedt (VMware)2018-10-271-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The stack tracer traces every function call checking the current stack (in non interrupt context), looking for the deepest stack, and saving it when it finds a new max depth. The problem is that it calls save_stack_trace(), and with the new ORC unwinder, it can skip too much. As it looks at the ip of the function call in the backtrace to find where it should start, it doesn't need to skip anything. The stack trace selftest would fail when the kernel was complied with the ORC UNDWINDER enabled. Without skipping functions when doing the stack trace, it now passes again. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | tracing: Export trace_dump_stack to modulesNikolay Borisov2018-10-271-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is no reason for this function to be unexprted and it's a useful debugging aid. Link: http://lkml.kernel.org/r/1539759103-5923-1-git-send-email-nborisov@suse.com Signed-off-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | tracing: probeevent: Fix uninitialized used of offset in parse argsSteven Rostedt (VMware)2018-10-121-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Dan's smatch utility found an uninitialized use of offset in a path in parse_probe_args(). Unless an offset is specifically specified for commands that allow them, it should default to zero. Link: http://lkml.kernel.org/r/20181012134246.5doqaobxunlqqs53@mwanda Fixes: 533059281ee5 ("tracing: probeevent: Introduce new argument fetching code") Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | tracing/kprobes: Allow kprobe-events to record module symbolMasami Hiramatsu2018-10-113-10/+68
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Allow kprobe-events to record module symbols. Since data symbols in a non-loaded module doesn't exist, it fails to define such symbol as an argument of kprobe-event. But if the kprobe event is defined on that module, we can defer to resolve the symbol address. Note that if given symbol is not found, the event is kept unavailable. User can enable it but the event is not recorded. Link: http://lkml.kernel.org/r/153547312336.26502.11432902826345374463.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | tracing/kprobes: Check the probe on unloaded module correctlyMasami Hiramatsu2018-10-111-13/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Current kprobe event doesn't checks correctly whether the given event is on unloaded module or not. It just checks the event has ":" in the name. That is not enough because if we define a probe on non-exist symbol on loaded module, it allows to define that (with warning message) To ensure it correctly, this searches the module name on loaded module list and only if there is not, it allows to define it. (this event will be available when the target module is loaded) Link: http://lkml.kernel.org/r/153547309528.26502.8300278470528281328.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | tracing/uprobes: Fix to return -EFAULT if copy_from_user failedMasami Hiramatsu2018-10-111-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix probe_mem_read() to return -EFAULT if copy_from_user() failed. The copy_from_user() returns remaining bytes when it failed, but probe_mem_read() caller expects it returns error code like as probe_kernel_read(). Link: http://lkml.kernel.org/r/153547306719.26502.8353484532699160223.stgit@devbox Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | tracing: probeevent: Add $argN for accessing function argsMasami Hiramatsu2018-10-115-20/+49
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add $argN special fetch variable for accessing function arguments. This allows user to trace the Nth argument easily at the function entry. Note that this returns most probably assignment of registers and stacks. In some case, it may not work well. If you need to access correct registers or stacks you should use perf-probe. Link: http://lkml.kernel.org/r/152465888632.26224.3412465701570253696.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | tracing: probeevent: Add array type supportMasami Hiramatsu2018-10-114-40/+170
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add array type support for probe events. This allows user to get arraied types from memory address. The array type syntax is TYPE[N] Where TYPE is one of types (u8/16/32/64,s8/16/32/64, x8/16/32/64, symbol, string) and N is a fixed value less than 64. The string array type is a bit different from other types. For other base types, <base-type>[1] is equal to <base-type> (e.g. +0(%di):x32[1] is same as +0(%di):x32.) But string[1] is not equal to string. The string type itself represents "char array", but string array type represents "char * array". So, for example, +0(%di):string[1] is equal to +0(+0(%di)):string. Link: http://lkml.kernel.org/r/152465891533.26224.6150658225601339931.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | tracing: probeevent: Add symbol typeMasami Hiramatsu2018-10-113-4/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add "symbol" type to probeevent, which is an alias of u32 or u64 (depends on BITS_PER_LONG). This shows the result value in symbol+offset style. This type is only available with kprobe events. Link: http://lkml.kernel.org/r/152465882860.26224.14779072294412467338.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | tracing: probeevent: Unify fetch_insn processing common partMasami Hiramatsu2018-10-113-82/+63Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Unify the fetch_insn bottom process (from stage 2: dereference indirect data) from kprobe and uprobe events, since those are mostly same. Link: http://lkml.kernel.org/r/152465879965.26224.8547240824606804815.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | tracing: probeevent: Append traceprobe_ for exported functionMasami Hiramatsu2018-10-114-6/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Append traceprobe_ for exported function set_print_fmt() as same as other functions. Link: http://lkml.kernel.org/r/152465877071.26224.11143125027282999726.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | tracing: probeevent: Return consumed bytes of dynamic areaMasami Hiramatsu2018-10-114-110/+88Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Cleanup string fetching routine so that returns the consumed bytes of dynamic area and store the string information as data_loc format instead of data_rloc. This simplifies the fetcharg loop. Link: http://lkml.kernel.org/r/152465874163.26224.12125143907501289031.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | tracing: probeevent: Unify fetch type tablesMasami Hiramatsu2018-10-114-75/+39Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Unify {k,u}probe_fetch_type_table to probe_fetch_type_table because the main difference of those type tables (fetcharg methods) are gone. Now we can consolidate it. Link: http://lkml.kernel.org/r/152465871274.26224.13999436317830479698.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | tracing: probeevent: Introduce new argument fetching codeMasami Hiramatsu2018-10-115-678/+491Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Replace {k,u}probe event argument fetching framework with switch-case based. Currently that is implemented with structures, macros and chain of function-pointers, which is more complicated than necessary and may get a performance penalty by retpoline. This simplify that with an array of "fetch_insn" (opcode and oprands), and make process_fetch_insn() just interprets it. No function pointers are used. Link: http://lkml.kernel.org/r/152465868340.26224.2551120475197839464.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | tracing: probeevent: Remove NOKPROBE_SYMBOL from print functionsMasami Hiramatsu2018-10-111-3/+1Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Remove unneeded NOKPROBE_SYMBOL from print functions since the print functions are only used when printing out the trace data, and not from kprobe handler. Link: http://lkml.kernel.org/r/152465865422.26224.10111548170594014954.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | tracing: probeevent: Cleanup argument field definitionMasami Hiramatsu2018-10-114-41/+29Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Cleanup event argument definition code in one place for maintenancability. Link: http://lkml.kernel.org/r/152465862529.26224.9068605421476018902.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | tracing: probeevent: Cleanup print argument functionsMasami Hiramatsu2018-10-114-31/+29Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Cleanup the print-argument function to decouple it into print-name and print-value, so that it can support more flexible expression, like array type. Link: http://lkml.kernel.org/r/152465859635.26224.13452846788717102315.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | trace_uprobe: support reference counter in fd-based uprobeSong Liu2018-10-113-5/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch enables uprobes with reference counter in fd-based uprobe. Highest 32 bits of perf_event_attr.config is used to stored offset of the reference count (semaphore). Format information in /sys/bus/event_source/devices/uprobe/format/ is updated to reflect this new feature. Link: http://lkml.kernel.org/r/20181002053636.1896903-1-songliubraving@fb.com Cc: Oleg Nesterov <oleg@redhat.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-and-tested-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com> Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | trace_uprobe/sdt: Prevent multiple reference counter for same uprobeRavi Bangoria2018-09-241-2/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We assume to have only one reference counter for one uprobe. Don't allow user to add multiple trace_uprobe entries having same inode+offset but different reference counter. Ex, # echo "p:sdt_tick/loop2 /home/ravi/tick:0x6e4(0x10036)" > uprobe_events # echo "p:sdt_tick/loop2_1 /home/ravi/tick:0x6e4(0xfffff)" >> uprobe_events bash: echo: write error: Invalid argument # dmesg trace_kprobe: Reference counter offset mismatch. There is one exception though: When user is trying to replace the old entry with the new one, we allow this if the new entry does not conflict with any other existing entries. Link: http://lkml.kernel.org/r/20180820044250.11659-4-ravi.bangoria@linux.ibm.com Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Reviewed-by: Song Liu <songliubraving@fb.com> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Tested-by: Song Liu <songliubraving@fb.com> Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | uprobes: Support SDT markers having reference count (semaphore)Ravi Bangoria2018-09-242-4/+36
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Userspace Statically Defined Tracepoints[1] are dtrace style markers inside userspace applications. Applications like PostgreSQL, MySQL, Pthread, Perl, Python, Java, Ruby, Node.js, libvirt, QEMU, glib etc have these markers embedded in them. These markers are added by developer at important places in the code. Each marker source expands to a single nop instruction in the compiled code but there may be additional overhead for computing the marker arguments which expands to couple of instructions. In case the overhead is more, execution of it can be omitted by runtime if() condition when no one is tracing on the marker: if (reference_counter > 0) { Execute marker instructions; } Default value of reference counter is 0. Tracer has to increment the reference counter before tracing on a marker and decrement it when done with the tracing. Implement the reference counter logic in core uprobe. User will be able to use it from trace_uprobe as well as from kernel module. New trace_uprobe definition with reference counter will now be: <path>:<offset>[(ref_ctr_offset)] where ref_ctr_offset is an optional field. For kernel module, new variant of uprobe_register() has been introduced: uprobe_register_refctr(inode, offset, ref_ctr_offset, consumer) No new variant for uprobe_unregister() because it's assumed to have only one reference counter for one uprobe. [1] https://sourceware.org/systemtap/wiki/UserSpaceProbeImplementation Note: 'reference counter' is called as 'semaphore' in original Dtrace (or Systemtap, bcc and even in ELF) documentation and code. But the term 'semaphore' is misleading in this context. This is just a counter used to hold number of tracers tracing on a marker. This is not really used for any synchronization. So we are calling it a 'reference counter' in kernel / perf code. Link: http://lkml.kernel.org/r/20180820044250.11659-2-ravi.bangoria@linux.ibm.com Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> [Only trace_uprobe.c] Reviewed-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Song Liu <songliubraving@fb.com> Tested-by: Song Liu <songliubraving@fb.com> Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | tracing/kprobe: Remove unneeded extra strchr() from create_trace_kprobe()Steven Rostedt (VMware)2018-09-241-3/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | By utilizing a temporary variable, we can avoid adding another call to strchr(). Instead, save the first call to a temp variable, and then use that variable as the reference to set the event variable. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* | | | Merge tag 'trace-v4.19-rc8-3' of ↵Linus Torvalds2018-10-301-1/+3
|\ \ \ \ | |_|_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: "Masami had a couple more fixes to the synthetic events. One was a proper error return value, and the other is for the self tests" * tag 'trace-v4.19-rc8-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: selftests/ftrace: Fix synthetic event test to delete event correctly tracing: Return -ENOENT if there is no target synthetic event
| * | | tracing: Return -ENOENT if there is no target synthetic eventMasami Hiramatsu2018-10-281-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Return -ENOENT error if there is no target synthetic event. This notices an operation failure to user as below; # echo 'wakeup_latency u64 lat; pid_t pid;' > synthetic_events # echo '!wakeup' >> synthetic_events sh: write error: No such file or directory Link: http://lkml.kernel.org/r/154013449986.25576.9487131386597290172.stgit@devbox Acked-by: Tom Zanussi <zanussi@linux.intel.com> Tested-by: Tom Zanussi <zanussi@linux.intel.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Rajvi Jingar <rajvi.jingar@intel.com> Cc: stable@vger.kernel.org Fixes: 4b147936fa50 ('tracing: Add support for 'synthetic' events') Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* | | | Merge tag 'for-4.20/block-20181021' of git://git.kernel.dk/linux-blockLinus Torvalds2018-10-221-2/+2
|\ \ \ \ | |/ / / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull block layer updates from Jens Axboe: "This is the main pull request for block changes for 4.20. This contains: - Series enabling runtime PM for blk-mq (Bart). - Two pull requests from Christoph for NVMe, with items such as; - Better AEN tracking - Multipath improvements - RDMA fixes - Rework of FC for target removal - Fixes for issues identified by static checkers - Fabric cleanups, as prep for TCP transport - Various cleanups and bug fixes - Block merging cleanups (Christoph) - Conversion of drivers to generic DMA mapping API (Christoph) - Series fixing ref count issues with blkcg (Dennis) - Series improving BFQ heuristics (Paolo, et al) - Series improving heuristics for the Kyber IO scheduler (Omar) - Removal of dangerous bio_rewind_iter() API (Ming) - Apply single queue IPI redirection logic to blk-mq (Ming) - Set of fixes and improvements for bcache (Coly et al) - Series closing a hotplug race with sysfs group attributes (Hannes) - Set of patches for lightnvm: - pblk trace support (Hans) - SPDX license header update (Javier) - Tons of refactoring patches to cleanly abstract the 1.2 and 2.0 specs behind a common core interface. (Javier, Matias) - Enable pblk to use a common interface to retrieve chunk metadata (Matias) - Bug fixes (Various) - Set of fixes and updates to the blk IO latency target (Josef) - blk-mq queue number updates fixes (Jianchao) - Convert a bunch of drivers from the old legacy IO interface to blk-mq. This will conclude with the removal of the legacy IO interface itself in 4.21, with the rest of the drivers (me, Omar) - Removal of the DAC960 driver. The SCSI tree will introduce two replacement drivers for this (Hannes)" * tag 'for-4.20/block-20181021' of git://git.kernel.dk/linux-block: (204 commits) block: setup bounce bio_sets properly blkcg: reassociate bios when make_request() is called recursively blkcg: fix edge case for blk_get_rl() under memory pressure nvme-fabrics: move controller options matching to fabrics nvme-rdma: always have a valid trsvcid mtip32xx: fully switch to the generic DMA API rsxx: switch to the generic DMA API umem: switch to the generic DMA API sx8: switch to the generic DMA API sx8: remove dead IF_64BIT_DMA_IS_POSSIBLE code skd: switch to the generic DMA API ubd: remove use of blk_rq_map_sg nvme-pci: remove duplicate check drivers/block: Remove DAC960 driver nvme-pci: fix hot removal during error handling nvmet-fcloop: suppress a compiler warning nvme-core: make implicit seed truncation explicit nvmet-fc: fix kernel-doc headers nvme-fc: rework the request initialization code nvme-fc: introduce struct nvme_fcp_op_w_sgl ...
| * | | Merge tag 'v4.19-rc6' into for-4.20/blockJens Axboe2018-10-011-0/+2
| |\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge -rc6 in, for two reasons: 1) Resolve a trivial conflict in the blk-mq-tag.c documentation 2) A few important regression fixes went into upstream directly, so they aren't in the 4.20 branch. Signed-off-by: Jens Axboe <axboe@kernel.dk> * tag 'v4.19-rc6': (780 commits) Linux 4.19-rc6 MAINTAINERS: fix reference to moved drivers/{misc => auxdisplay}/panel.c cpufreq: qcom-kryo: Fix section annotations perf/core: Add sanity check to deal with pinned event failure xen/blkfront: correct purging of persistent grants Revert "xen/blkfront: When purging persistent grants, keep them in the buffer" selftests/powerpc: Fix Makefiles for headers_install change blk-mq: I/O and timer unplugs are inverted in blktrace dax: Fix deadlock in dax_lock_mapping_entry() x86/boot: Fix kexec booting failure in the SEV bit detection code bcache: add separate workqueue for journal_write to avoid deadlock drm/amd/display: Fix Edid emulation for linux drm/amd/display: Fix Vega10 lightup on S3 resume drm/amdgpu: Fix vce work queue was not cancelled when suspend Revert "drm/panel: Add device_link from panel device to DRM device" xen/blkfront: When purging persistent grants, keep them in the buffer clocksource/drivers/timer-atmel-pit: Properly handle error cases block: fix deadline elevator drain for zoned block devices ACPI / hotplug / PCI: Don't scan for non-hotplug bridges if slot is not bridge drm/syncobj: Don't leak fences when WAIT_FOR_SUBMIT is set ... Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | blkcg: remove bio->bi_css and instead use bio->bi_blkgDennis Zhou (Facebook)2018-09-221-2/+2
| | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Prior patches ensured that all bios are now associated with some blkg. This now makes bio->bi_css unnecessary as blkg maintains a reference to the blkcg already. This patch removes the field bi_css and transfers corresponding uses to access via bi_blkg. Signed-off-by: Dennis Zhou <dennisszhou@gmail.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | | tracing: Fix synthetic event to allow semicolon at endMasami Hiramatsu2018-10-191-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix synthetic event to allow independent semicolon at end. The synthetic_events interface accepts a semicolon after the last word if there is no space. # echo "myevent u64 var;" >> synthetic_events But if there is a space, it returns an error. # echo "myevent u64 var ;" > synthetic_events sh: write error: Invalid argument This behavior is difficult for users to understand. Let's allow the last independent semicolon too. Link: http://lkml.kernel.org/r/153986835420.18251.2191216690677025744.stgit@devbox Cc: Shuah Khan <shuah@kernel.org> Cc: Tom Zanussi <tom.zanussi@linux.intel.com> Cc: stable@vger.kernel.org Fixes: commit 4b147936fa50 ("tracing: Add support for 'synthetic' events") Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* | | tracing: Fix synthetic event to accept unsigned modifierMasami Hiramatsu2018-10-191-6/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix synthetic event to accept unsigned modifier for its field type correctly. Currently, synthetic_events interface returns error for "unsigned" modifiers as below; # echo "myevent unsigned long var" >> synthetic_events sh: write error: Invalid argument This is because argv_split() breaks "unsigned long" into "unsigned" and "long", but parse_synth_field() doesn't expected it. With this fix, synthetic_events can handle the "unsigned long" correctly like as below; # echo "myevent unsigned long var" >> synthetic_events # cat synthetic_events myevent unsigned long var Link: http://lkml.kernel.org/r/153986832571.18251.8448135724590496531.stgit@devbox Cc: Shuah Khan <shuah@kernel.org> Cc: Tom Zanussi <tom.zanussi@linux.intel.com> Cc: stable@vger.kernel.org Fixes: commit 4b147936fa50 ("tracing: Add support for 'synthetic' events") Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* | | tracing: Use trace_clock_local() for looping in preemptirq_delay_test.cSteven Rostedt (VMware)2018-10-171-5/+5
| |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The preemptirq_delay_test module is used for the ftrace selftest code that tests the latency tracers. The problem is that it uses ktime for the delay loop, and then checks the tracer to see if the delay loop is caught, but the tracer uses trace_clock_local() which uses various different other clocks to measure the latency. As ktime uses the clock cycles, and the code then converts that to nanoseconds, it causes rounding errors, and the preemptirq latency tests are failing due to being off by 1 (it expects to see a delay of 500000 us, but the delay is only 499999 us). This is happening due to a rounding error in the ktime (which is totally legit). The purpose of the test is to see if it can catch the delay, not to test the accuracy between trace_clock_local() and ktime_get(). Best to use apples to apples, and have the delay loop use the same clock as the latency tracer does. Cc: stable@vger.kernel.org Fixes: f96e8577da102 ("lib: Add module for testing preemptoff/irqsoff latency tracers") Acked-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* | ring-buffer: Allow for rescheduling when removing pagesVaibhav Nagarnaik2018-09-181-0/+2
|/ | | | | | | | | | | | | | | | | | | | | When reducing ring buffer size, pages are removed by scheduling a work item on each CPU for the corresponding CPU ring buffer. After the pages are removed from ring buffer linked list, the pages are free()d in a tight loop. The loop does not give up CPU until all pages are removed. In a worst case behavior, when lot of pages are to be freed, it can cause system stall. After the pages are removed from the list, the free() can happen while the work is rescheduled. Call cond_resched() in the loop to prevent the system hangup. Link: http://lkml.kernel.org/r/20180907223129.71994-1-vnagarnaik@google.com Cc: stable@vger.kernel.org Fixes: 83f40318dab00 ("ring-buffer: Make removal of ring buffer pages atomic") Reported-by: Jason Behmer <jbehmer@google.com> Signed-off-by: Vaibhav Nagarnaik <vnagarnaik@google.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* Merge tag 'trace-v4.19-1' of ↵Linus Torvalds2018-08-233-1/+25
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: "Masami found an off by one bug in the code that keeps "notrace" functions from being traced by kprobes. During my testing, I found that there's places that we may want to add kprobes to notrace, thus we may end up changing this code before 4.19 is released. The history behind this change is that we found that adding kprobes to various notrace functions caused the kernel to crashed. We took the safe route and decided not to allow kprobes to trace any notrace function. But because notrace is added to functions that just cause weird side effects to the function tracer, but are still safe, preventing kprobes for all notrace functios may be too much of a big hammer. One such place is __schedule() is marked notrace, to keep function tracer from doing strange recursive loops when it gets traced with NEED_RESCHED set. With this change, one can not add kprobes to the scheduler. Masami also added code to use gcov on ftrace" * tag 'trace-v4.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing/kprobes: Fix to check notrace function with correct range tracing: Allow gcov profiling on only ftrace subsystem
| * tracing/kprobes: Fix to check notrace function with correct rangeMasami Hiramatsu2018-08-211-1/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix within_notrace_func() to check notrace function correctly. Since the ftrace_location_range(start, end) function checks the range inclusively (start <= ftrace-loc <= end), the end address must not include the entry address of next function. However, within_notrace_func() uses kallsyms_lookup_size_offset() to get the function size and calculate the end address from adding the size to the entry address. This means the end address is the entry address of the next function. In the result, within_notrace_func() fails to find notrace function if the next function of the target function is ftraced. Let's subtract 1 from the end address so that ftrace_location_range() can check it correctly. Link: http://lkml.kernel.org/r/153485669706.16611.17726752296213785504.stgit@devbox Fixes: commit 45408c4f9250 ("tracing: kprobes: Prohibit probing on notrace function") Reported-by: Michael Rodin <michael@rodin.online> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * tracing: Allow gcov profiling on only ftrace subsystemMasami Hiramatsu2018-08-212-0/+17
| | | | | | | | | | | | | | | | | | | | | | Add GCOV_PROFILE_FTRACE to allow gcov profiling on only files in ftrace subsystem. This config option will be used for checking kselftest/ftrace coverage. Link: http://lkml.kernel.org/r/153483647755.32472.4746349899604275441.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* | Merge tag 'for-4.19/post-20180822' of git://git.kernel.dk/linux-blockLinus Torvalds2018-08-221-0/+4
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull more block updates from Jens Axboe: - Set of bcache fixes and changes (Coly) - The flush warn fix (me) - Small series of BFQ fixes (Paolo) - wbt hang fix (Ming) - blktrace fix (Steven) - blk-mq hardware queue count update fix (Jianchao) - Various little fixes * tag 'for-4.19/post-20180822' of git://git.kernel.dk/linux-block: (31 commits) block/DAC960.c: make some arrays static const, shrinks object size blk-mq: sync the update nr_hw_queues with blk_mq_queue_tag_busy_iter blk-mq: init hctx sched after update ctx and hctx mapping block: remove duplicate initialization tracing/blktrace: Fix to allow setting same value pktcdvd: fix setting of 'ret' error return for a few cases block: change return type to bool block, bfq: return nbytes and not zero from struct cftype .write() method block, bfq: improve code of bfq_bfqq_charge_time block, bfq: reduce write overcharge block, bfq: always update the budget of an entity when needed block, bfq: readd missing reset of parent-entity service blk-wbt: fix IO hang in wbt_wait() block: don't warn for flush on read-only device bcache: add the missing comments for smp_mb()/smp_wmb() bcache: remove unnecessary space before ioctl function pointer arguments bcache: add missing SPDX header bcache: move open brace at end of function definitions to next line bcache: add static const prefix to char * array declarations bcache: fix code comments style ...
| * | tracing/blktrace: Fix to allow setting same valueSteven Rostedt (VMware)2018-08-161-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Masami Hiramatsu reported: Current trace-enable attribute in sysfs returns an error if user writes the same setting value as current one, e.g. # cat /sys/block/sda/trace/enable 0 # echo 0 > /sys/block/sda/trace/enable bash: echo: write error: Invalid argument # echo 1 > /sys/block/sda/trace/enable # echo 1 > /sys/block/sda/trace/enable bash: echo: write error: Device or resource busy But this is not a preferred behavior, it should ignore if new setting is same as current one. This fixes the problem as below. # cat /sys/block/sda/trace/enable 0 # echo 0 > /sys/block/sda/trace/enable # echo 1 > /sys/block/sda/trace/enable # echo 1 > /sys/block/sda/trace/enable Link: http://lkml.kernel.org/r/20180816103802.08678002@gandalf.local.home Cc: Ingo Molnar <mingo@redhat.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: linux-block@vger.kernel.org Cc: stable@vger.kernel.org Fixes: cd649b8bb830d ("blktrace: remove sysfs_blk_trace_enable_show/store()") Reported-by: Masami Hiramatsu <mhiramat@kernel.org> Tested-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | | Merge tag 'trace-v4.19' of ↵Linus Torvalds2018-08-2135-423/+472
|\ \ \ | | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: - Restructure of lockdep and latency tracers This is the biggest change. Joel Fernandes restructured the hooks from irqs and preemption disabling and enabling. He got rid of a lot of the preprocessor #ifdef mess that they caused. He turned both lockdep and the latency tracers to use trace events inserted in the preempt/irqs disabling paths. But unfortunately, these started to cause issues in corner cases. Thus, parts of the code was reverted back to where lockdep and the latency tracers just get called directly (without using the trace events). But because the original change cleaned up the code very nicely we kept that, as well as the trace events for preempt and irqs disabling, but they are limited to not being called in NMIs. - Have trace events use SRCU for "rcu idle" calls. This was required for the preempt/irqs off trace events. But it also had to not allow them to be called in NMI context. Waiting till Paul makes an NMI safe SRCU API. - New notrace SRCU API to allow trace events to use SRCU. - Addition of mcount-nop option support - SPDX headers replacing GPL templates. - Various other fixes and clean ups. - Some fixes are marked for stable, but were not fully tested before the merge window opened. * tag 'trace-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (44 commits) tracing: Fix SPDX format headers to use C++ style comments tracing: Add SPDX License format tags to tracing files tracing: Add SPDX License format to bpf_trace.c blktrace: Add SPDX License format header s390/ftrace: Add -mfentry and -mnop-mcount support tracing: Add -mcount-nop option support tracing: Avoid calling cc-option -mrecord-mcount for every Makefile tracing: Handle CC_FLAGS_FTRACE more accurately Uprobe: Additional argument arch_uprobe to uprobe_write_opcode() Uprobes: Simplify uprobe_register() body tracepoints: Free early tracepoints after RCU is initialized uprobes: Use synchronize_rcu() not synchronize_sched() tracing: Fix synchronizing to event changes with tracepoint_synchronize_unregister() ftrace: Remove unused pointer ftrace_swapper_pid tracing: More reverting of "tracing: Centralize preemptirq tracepoints and unify their usage" tracing/irqsoff: Handle preempt_count for different configs tracing: Partial revert of "tracing: Centralize preemptirq tracepoints and unify their usage" tracing: irqsoff: Account for additional preempt_disable trace: Use rcu_dereference_raw for hooks from trace-event subsystem tracing/kprobes: Fix within_notrace_func() to check only notrace functions ...
| * | tracing: Fix SPDX format headers to use C++ style commentsSteven Rostedt (VMware)2018-08-178-8/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The Linux kernel adopted the SPDX License format headers to ease license compliance management, and uses the C++ '//' style comments for the SPDX header tags. Some files in the tracing directory used the C style /* */ comments for them. To be consistent across all files, replace the /* */ C style SPDX tags with the C++ // SPDX tags. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | tracing: Add SPDX License format tags to tracing filesSteven Rostedt (VMware)2018-08-1720-102/+20Star
| | | | | | | | | | | | | | | | | | Add the SPDX License header to ease license compliance management. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | tracing: Add SPDX License format to bpf_trace.cSteven Rostedt (VMware)2018-08-171-4/+1Star
| | | | | | | | | | | | | | | | | | | | | | | | Add the SPDX License header to ease license compliance management. Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | blktrace: Add SPDX License format headerSteven Rostedt (VMware)2018-08-161-13/+1Star
| | | | | | | | | | | | | | | | | | | | | Add the SPDX License header to ease license compliance management. Acked-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | tracing: Add -mcount-nop option supportVasily Gorbik2018-08-162-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | -mcount-nop gcc option generates the calls to the profiling functions as nops which allows to avoid patching mcount jump with NOP instructions initially. -mcount-nop gcc option will be activated if platform selects HAVE_NOP_MCOUNT and gcc actually supports it. In addition to that CC_USING_NOP_MCOUNT is defined and could be used by architectures to adapt ftrace patching behavior. Link: http://lkml.kernel.org/r/patch-3.thread-aa7b8d.git-e02ed2dc082b.your-ad-here.call-01533557518-ext-9465@work.hours Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | uprobes: Use synchronize_rcu() not synchronize_sched()Steven Rostedt (VMware)2018-08-101-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | While debugging another bug, I was looking at all the synchronize*() functions being used in kernel/trace, and noticed that trace_uprobes was using synchronize_sched(), with a comment to synchronize with {u,ret}_probe_trace_func(). When looking at those functions, the data is protected with "rcu_read_lock()" and not with "rcu_read_lock_sched()". This is using the wrong synchronize_*() function. Link: http://lkml.kernel.org/r/20180809160553.469e1e32@gandalf.local.home Cc: stable@vger.kernel.org Fixes: 70ed91c6ec7f8 ("tracing/uprobes: Support ftrace_event_file base multibuffer") Acked-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | tracing: Fix synchronizing to event changes with ↵Steven Rostedt (VMware)2018-08-104-14/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | tracepoint_synchronize_unregister() Now that some trace events can be protected by srcu_read_lock(tracepoint_srcu), we need to make sure all locations that depend on this are also protected. There were many places that did a synchronize_sched() thinking that it was enough to protect againts access to trace events. This use to be the case, but now that we use SRCU for _rcuidle() trace events, they may not be protected by synchronize_sched(), as they may be called in paths that RCU is not watching for preempt disable. Fixes: e6753f23d961d ("tracepoint: Make rcuidle tracepoint callers use SRCU") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | ftrace: Remove unused pointer ftrace_swapper_pidColin Ian King2018-08-101-2/+0Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pointer ftrace_swapper_pid is defined but is never used hence it is redundant and can be removed. The use of this variable was removed in commit 345ddcc882d8 ("ftrace: Have set_ftrace_pid use the bitmap like events do"). Cleans up clang warning: warning: 'ftrace_swapper_pid' defined but not used [-Wunused-const-variable=] Link: http://lkml.kernel.org/r/20180809125609.13142-1-colin.king@canonical.com Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | tracing: More reverting of "tracing: Centralize preemptirq tracepoints and ↵Steven Rostedt (VMware)2018-08-103-50/+38Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | unify their usage" Joel Fernandes created a nice patch that cleaned up the duplicate hooks used by lockdep and irqsoff latency tracer. It made both use tracepoints. But the latency tracer is triggering warnings when using tracepoints to call into the latency tracer's routines. Mainly, they can be called from NMI context. If that happens, then the SRCU may not work properly because on some architectures, SRCU is not safe to be called in both NMI and non-NMI context. This is a partial revert of the clean up patch c3bc8fd637a9 ("tracing: Centralize preemptirq tracepoints and unify their usage") that adds back the direct calls into the latency tracer. It also only calls the trace events when not in NMI. Link: http://lkml.kernel.org/r/20180809210654.622445925@goodmis.org Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org> Fixes: c3bc8fd637a9 ("tracing: Centralize preemptirq tracepoints and unify their usage") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>