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2014-12-18Merge tag 'pm+acpi-3.19-rc1-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull more ACPI and power management updates from Rafael Wysocki: "These are regression fixes (leds-gpio, ACPI backlight driver, operating performance points library, ACPI device enumeration messages, cpupower tool), other bug fixes (ACPI EC driver, ACPI device PM), some cleanups in the operating performance points (OPP) framework, continuation of CONFIG_PM_RUNTIME elimination, a couple of minor intel_pstate driver changes, a new MAINTAINERS entry for it and an ACPI fan driver change needed for better support of thermal management in user space. Specifics: - Fix a regression in leds-gpio introduced by a recent commit that inadvertently changed the name of one of the properties used by the driver (Fabio Estevam). - Fix a regression in the ACPI backlight driver introduced by a recent fix that missed one special case that had to be taken into account (Aaron Lu). - Drop the level of some new kernel messages from the ACPI core introduced by a recent commit to KERN_DEBUG which they should have used from the start and drop some other unuseful KERN_ERR messages printed by ACPI (Rafael J Wysocki). - Revert an incorrect commit modifying the cpupower tool (Prarit Bhargava). - Fix two regressions introduced by recent commits in the OPP library and clean up some existing minor issues in that code (Viresh Kumar). - Continue to replace CONFIG_PM_RUNTIME with CONFIG_PM throughout the tree (or drop it where that can be done) in order to make it possible to eliminate CONFIG_PM_RUNTIME (Rafael J Wysocki, Ulf Hansson, Ludovic Desroches). There will be one more "CONFIG_PM_RUNTIME removal" batch after this one, because some new uses of it have been introduced during the current merge window, but that should be sufficient to finally get rid of it. - Make the ACPI EC driver more robust against race conditions related to GPE handler installation failures (Lv Zheng). - Prevent the ACPI device PM core code from attempting to disable GPEs that it has not enabled which confuses ACPICA and makes it report errors unnecessarily (Rafael J Wysocki). - Add a "force" command line switch to the intel_pstate driver to make it possible to override the blacklisting of some systems in that driver if needed (Ethan Zhao). - Improve intel_pstate code documentation and add a MAINTAINERS entry for it (Kristen Carlson Accardi). - Make the ACPI fan driver create cooling device interfaces witn names that reflect the IDs of the ACPI device objects they are associated with, except for "generic" ACPI fans (PNP ID "PNP0C0B"). That's necessary for user space thermal management tools to be able to connect the fans with the parts of the system they are supposed to be cooling properly. From Srinivas Pandruvada" * tag 'pm+acpi-3.19-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (32 commits) MAINTAINERS: add entry for intel_pstate ACPI / video: update the skip case for acpi_video_device_in_dod() power / PM: Eliminate CONFIG_PM_RUNTIME NFC / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM SCSI / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM ACPI / EC: Fix unexpected ec_remove_handlers() invocations Revert "tools: cpupower: fix return checks for sysfs_get_idlestate_count()" tracing / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM x86 / PM: Replace CONFIG_PM_RUNTIME in io_apic.c PM: Remove the SET_PM_RUNTIME_PM_OPS() macro mmc: atmel-mci: use SET_RUNTIME_PM_OPS() macro PM / Kconfig: Replace PM_RUNTIME with PM in dependencies ARM / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM sound / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM phy / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM video / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM tty / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM spi: Replace CONFIG_PM_RUNTIME with CONFIG_PM ACPI / PM: Do not disable wakeup GPEs that have not been enabled ACPI / utils: Drop error messages from acpi_evaluate_reference() ...
2014-12-16Merge tag 'trace-3.19-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: "As the merge window is still open, and this code was not as complex as I thought it might be. I'm pushing this in now. This will allow Thomas to debug his irq work for 3.20. This adds two new features: 1) Allow traceopoints to be enabled right after mm_init(). By passing in the trace_event= kernel command line parameter, tracepoints can be enabled at boot up. For debugging things like the initialization of interrupts, it is needed to have tracepoints enabled very early. People have asked about this before and this has been on my todo list. As it can be helpful for Thomas to debug his upcoming 3.20 IRQ work, I'm pushing this now. This way he can add tracepoints into the IRQ set up and have users enable them when things go wrong. 2) Have the tracepoints printed via printk() (the console) when they are triggered. If the irq code locks up or reboots the box, having the tracepoint output go into the kernel ring buffer is useless for debugging. But being able to add the tp_printk kernel command line option along with the trace_event= option will have these tracepoints printed as they occur, and that can be really useful for debugging early lock up or reboot problems. This code is not that intrusive and it passed all my tests. Thomas tried them out too and it works for his needs. Link: http://lkml.kernel.org/r/20141214201609.126831471@goodmis.org" * tag 'trace-3.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing: Add tp_printk cmdline to have tracepoints go to printk() tracing: Move enabling tracepoints to just after rcu_init()
2014-12-15tracing: Add tp_printk cmdline to have tracepoints go to printk()Steven Rostedt (Red Hat)
Add the kernel command line tp_printk option that will have tracepoints that are active sent to printk() as well as to the trace buffer. Passing "tp_printk" will activate this. To turn it off, the sysctl /proc/sys/kernel/tracepoint_printk can have '0' echoed into it. Note, this only works if the cmdline option is used. Echoing 1 into the sysctl file without the cmdline option will have no affect. Note, this is a dangerous option. Having high frequency tracepoints send their data to printk() can possibly cause a live lock. This is another reason why this is only active if the command line option is used. Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1412121539300.16494@nanos Suggested-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-12-15tracing: Move enabling tracepoints to just after rcu_init()Steven Rostedt (Red Hat)
Enabling tracepoints at boot up can be very useful. The tracepoint can be initialized right after RCU has been. There's no need to wait for the early_initcall() to be called. That's too late for some things that can use tracepoints for debugging. Move the logic to enable tracepoints out of the initcalls and into init/main.c to right after rcu_init(). This also allows trace_printk() to be used early too. Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1412121539300.16494@nanos Link: http://lkml.kernel.org/r/20141214164104.307127356@goodmis.org Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Suggested-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-12-13Merge branch 'for-3.19/core' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block driver core update from Jens Axboe: "This is the pull request for the core block IO changes for 3.19. Not a huge round this time, mostly lots of little good fixes: - Fix a bug in sysfs blktrace interface causing a NULL pointer dereference, when enabled/disabled through that API. From Arianna Avanzini. - Various updates/fixes/improvements for blk-mq: - A set of updates from Bart, mostly fixing buts in the tag handling. - Cleanup/code consolidation from Christoph. - Extend queue_rq API to be able to handle batching issues of IO requests. NVMe will utilize this shortly. From me. - A few tag and request handling updates from me. - Cleanup of the preempt handling for running queues from Paolo. - Prevent running of unmapped hardware queues from Ming Lei. - Move the kdump memory limiting check to be in the correct location, from Shaohua. - Initialize all software queues at init time from Takashi. This prevents a kobject warning when CPUs are brought online that weren't online when a queue was registered. - Single writeback fix for I_DIRTY clearing from Tejun. Queued with the core IO changes, since it's just a single fix. - Version X of the __bio_add_page() segment addition retry from Maurizio. Hope the Xth time is the charm. - Documentation fixup for IO scheduler merging from Jan. - Introduce (and use) generic IO stat accounting helpers for non-rq drivers, from Gu Zheng. - Kill off artificial limiting of max sectors in a request from Christoph" * 'for-3.19/core' of git://git.kernel.dk/linux-block: (26 commits) bio: modify __bio_add_page() to accept pages that don't start a new segment blk-mq: Fix uninitialized kobject at CPU hotplugging blktrace: don't let the sysfs interface remove trace from running list blk-mq: Use all available hardware queues blk-mq: Micro-optimize bt_get() blk-mq: Fix a race between bt_clear_tag() and bt_get() blk-mq: Avoid that __bt_get_word() wraps multiple times blk-mq: Fix a use-after-free blk-mq: prevent unmapped hw queue from being scheduled blk-mq: re-check for available tags after running the hardware queue blk-mq: fix hang in bt_get() blk-mq: move the kdump check to blk_mq_alloc_tag_set blk-mq: cleanup tag free handling blk-mq: use 'nr_cpu_ids' as highest CPU ID count for hwq <-> cpu map blk: introduce generic io stat accounting help function blk-mq: handle the single queue case in blk_mq_hctx_next_cpu genhd: check for int overflow in disk_expand_part_tbl() blk-mq: add blk_mq_free_hctx_request() blk-mq: export blk_mq_free_request() blk-mq: use get_cpu/put_cpu instead of preempt_disable/preempt_enable ...
2014-12-13tracing / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PMRafael J. Wysocki
After commit b2b49ccbdd54 (PM: Kconfig: Set PM_RUNTIME if PM_SLEEP is selected) PM_RUNTIME is always set if PM is set, so files that are build conditionally if CONFIG_PM_RUNTIME is set may now be build if CONFIG_PM is set. Replace CONFIG_PM_RUNTIME with CONFIG_PM in kernel/trace/Makefile for this reason. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Steven Rostedt <rostedt@goodmis.org.
2014-12-12Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial Pull trivial tree update from Jiri Kosina: "Usual stuff: documentation updates, printk() fixes, etc" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (24 commits) intel_ips: fix a type in error message cpufreq: cpufreq-dt: Move newline to end of error message ps3rom: fix error return code treewide: fix typo in printk and Kconfig ARM: dts: bcm63138: change "interupts" to "interrupts" Replace mentions of "list_struct" to "list_head" kernel: trace: fix printk message scsi: mpt2sas: fix ioctl in comment zbud, zswap: change module author email clocksource: Fix 'clcoksource' typo in comment arm: fix wording of "Crotex" in CONFIG_ARCH_EXYNOS3 help gpio: msm-v1: make boolean argument more obvious usb: Fix typo in usb-serial-simple.c PCI: Fix comment typo 'COMFIG_PM_OPS' powerpc: Fix comment typo 'CONIFG_8xx' powerpc: Fix comment typos 'CONFiG_ALTIVEC' clk: st: Spelling s/stucture/structure/ isci: Spelling s/stucture/structure/ usb: gadget: zero: Spelling s/infrastucture/infrastructure/ treewide: Fix company name in module descriptions ...
2014-12-10Merge tag 'trace-seq-buf-3.19' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull nmi-safe seq_buf printk update from Steven Rostedt: "This code is a fork from the trace-3.19 pull as it needed the trace_seq clean ups from that branch. This code solves the issue of performing stack dumps from NMI context. The issue is that printk() is not safe from NMI context as if the NMI were to trigger when a printk() was being performed, the NMI could deadlock from the printk() internal locks. This has been seen in practice. With lots of review from Petr Mladek, this code went through several iterations, and we feel that it is now at a point of quality to be accepted into mainline. Here's what is contained in this patch set: - Creates a "seq_buf" generic buffer utility that allows a descriptor to be passed around where functions can write their own "printk()" formatted strings into it. The generic version was pulled out of the trace_seq() code that was made specifically for tracing. - The seq_buf code was change to model the seq_file code. I have a patch (not included for 3.19) that converts the seq_file.c code over to use seq_buf.c like the trace_seq.c code does. This was done to make sure that seq_buf.c is compatible with seq_file.c. I may try to get that patch in for 3.20. - The seq_buf.c file was moved to lib/ to remove it from being dependent on CONFIG_TRACING. - The printk() was updated to allow for a per_cpu "override" of the internal calls. That is, instead of writing to the console, a call to printk() may do something else. This made it easier to allow the NMI to change what printk() does in order to call dump_stack() without needing to update that code as well. - Finally, the dump_stack from all CPUs via NMI code was converted to use the seq_buf code. The caller to trigger the NMI code would wait till all the NMIs finished, and then it would print the seq_buf data to the console safely from a non NMI context One added bonus is that this code also makes the NMI dump stack work on PREEMPT_RT kernels. As printk() includes sleeping locks on PREEMPT_RT, printk() only writes to console if the console does not use any rt_mutex converted spin locks. Which a lot do" * tag 'trace-seq-buf-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: x86/nmi: Fix use of unallocated cpumask_var_t printk/percpu: Define printk_func when printk is not defined x86/nmi: Perform a safe NMI stack trace on all CPUs printk: Add per_cpu printk func to allow printk to be diverted seq_buf: Move the seq_buf code to lib/ seq-buf: Make seq_buf_bprintf() conditional on CONFIG_BINARY_PRINTF tracing: Add seq_buf_get_buf() and seq_buf_commit() helper functions tracing: Have seq_buf use full buffer seq_buf: Add seq_buf_can_fit() helper function tracing: Add paranoid size check in trace_printk_seq() tracing: Use trace_seq_used() and seq_buf_used() instead of len tracing: Clean up tracing_fill_pipe_page() seq_buf: Create seq_buf_used() to find out how much was written tracing: Add a seq_buf_clear() helper and clear len and readpos in init tracing: Convert seq_buf fields to be like seq_file fields tracing: Convert seq_buf_path() to be like seq_path() tracing: Create seq_buf layer in trace_seq
2014-12-10Merge tag 'trace-3.19' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: "There was a lot of clean ups and minor fixes. One of those clean ups was to the trace_seq code. It also removed the return values to the trace_seq_*() functions and use trace_seq_has_overflowed() to see if the buffer filled up or not. This is similar to work being done to the seq_file code as well in another tree. Some of the other goodies include: - Added some "!" (NOT) logic to the tracing filter. - Fixed the frame pointer logic to the x86_64 mcount trampolines - Added the logic for dynamic trampolines on !CONFIG_PREEMPT systems. That is, the ftrace trampoline can be dynamically allocated and be called directly by functions that only have a single hook to them" * tag 'trace-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (55 commits) tracing: Truncated output is better than nothing tracing: Add additional marks to signal very large time deltas Documentation: describe trace_buf_size parameter more accurately tracing: Allow NOT to filter AND and OR clauses tracing: Add NOT to filtering logic ftrace/fgraph/x86: Have prepare_ftrace_return() take ip as first parameter ftrace/x86: Get rid of ftrace_caller_setup ftrace/x86: Have save_mcount_regs macro also save stack frames if needed ftrace/x86: Add macro MCOUNT_REG_SIZE for amount of stack used to save mcount regs ftrace/x86: Simplify save_mcount_regs on getting RIP ftrace/x86: Have save_mcount_regs store RIP in %rdi for first parameter ftrace/x86: Rename MCOUNT_SAVE_FRAME and add more detailed comments ftrace/x86: Move MCOUNT_SAVE_FRAME out of header file ftrace/x86: Have static tracing also use ftrace_caller_setup ftrace/x86: Have static function tracing always test for function graph kprobes: Add IPMODIFY flag to kprobe_ftrace_ops ftrace, kprobes: Support IPMODIFY flag to find IP modify conflict kprobes/ftrace: Recover original IP if pre_handler doesn't change it tracing/trivial: Fix typos and make an int into a bool tracing: Deletion of an unnecessary check before iput() ...
2014-12-09blktrace: don't let the sysfs interface remove trace from running listArianna Avanzini
Currently, blktrace can be started/stopped via its ioctl-based interface (used by the userspace blktrace tool) or via its ftrace interface. The function blk_trace_remove_queue(), called each time an "enable" tunable of the ftrace interface transitions to zero, removes the trace from the running list, even if no function from the sysfs interface adds it to such a list. This leads to a null pointer dereference. This commit changes the blk_trace_remove_queue() function so that it does not remove the blk_trace from the running list. v2: - Now the patch removes the invocation of list_del() instead of adding an useless if branch, as suggested by Namhyung Kim. Signed-off-by: Arianna Avanzini <avanzini.arianna@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2014-12-08Merge branch 'iov_iter' into for-nextAl Viro
2014-12-03tracing: Truncated output is better than nothingDan Carpenter
The initial reason for this patch is that I noticed that: if (len > TRACE_BUF_SIZE) is off by one. In this code, if len == TRACE_BUF_SIZE, then it means we have truncated the last character off the output string. If we truncate two or more characters then we exit without printing. After some discussion, we decided that printing truncated data is better than not printing at all so we should just use vscnprintf() and remove the test entirely. Also I have updated memcpy() to copy the NUL char instead of setting the NUL in a separate step. Link: http://lkml.kernel.org/r/20141127155752.GA21914@mwanda Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-12-03tracing: Add additional marks to signal very large time deltasByungchul Park
Currently, function graph tracer prints "!" or "+" just before function execution time to signal a function overhead, depending on the time. And some tracers tracing latency also print "!" or "+" just after time to signal overhead, depending on the interval between events. Even it is usually enough to do that, we sometimes need to signal for bigger execution time than 100 micro seconds. For example, I used function graph tracer to detect if there is any case that exit_mm() takes too much time. I did following steps in /sys/kernel/debug/tracing. It was easier to detect very large excution time with patched kernel than with original kernel. $ echo exit_mm > set_graph_function $ echo function_graph > current_tracer $ echo > trace $ cat trace_pipe > $LOGFILE ... (do something and terminate logging) $ grep "\\$" $LOGFILE 3) $ 22082032 us | } /* kernel_map_pages */ 3) $ 22082040 us | } /* free_pages_prepare */ 3) $ 22082113 us | } /* free_hot_cold_page */ 3) $ 22083455 us | } /* free_hot_cold_page_list */ 3) $ 22083895 us | } /* release_pages */ 3) $ 22177873 us | } /* free_pages_and_swap_cache */ 3) $ 22178929 us | } /* unmap_single_vma */ 3) $ 22198885 us | } /* unmap_vmas */ 3) $ 22206949 us | } /* exit_mmap */ 3) $ 22207659 us | } /* mmput */ 3) $ 22207793 us | } /* exit_mm */ And then, it was easy to find out that a schedule-out occured by sub_preempt_count() within kernel_map_pages(). To detect very large function exection time caused by either problematic function implementation or scheduling issues, this patch can be useful. Link: http://lkml.kernel.org/r/1416789259-24038-1-git-send-email-byungchul.park@lge.com Signed-off-by: Byungchul Park <byungchul.park@lge.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-12-03tracing: Allow NOT to filter AND and OR clausesSteven Rostedt (Red Hat)
Add support to allow not "!" for and (&&) and (||). That is: !(field1 == X && field2 == Y) Where the value of the full clause will be notted. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-12-03tracing: Add NOT to filtering logicSteven Rostedt (Red Hat)
Ted noticed that he could not filter on an event for a bit being cleared. That's because the filtering logic only tests event fields with a limited number of comparisons which, for bit logic, only include "&", which can test if a bit is set, but there's no good way to see if a bit is clear. This adds a way to do: !(field & 2048) Which returns true if the bit is not set, and false otherwise. Note, currently !(field1 == 10 && field2 == 15) is not supported. That is, the 'not' only works for direct comparisons, not for the AND and OR logic. Link: http://lkml.kernel.org/r/20141202021912.GA29096@thunk.org Link: http://lkml.kernel.org/r/20141202120430.71979060@gandalf.local.home Acked-by: Alexei Starovoitov <ast@plumgrid.com> Suggested-by: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-21ftrace, kprobes: Support IPMODIFY flag to find IP modify conflictMasami Hiramatsu
Introduce FTRACE_OPS_FL_IPMODIFY to avoid conflict among ftrace users who may modify regs->ip to change the execution path. If two or more users modify the regs->ip on the same function entry, one of them will be broken. So they must add IPMODIFY flag and make sure that ftrace_set_filter_ip() succeeds. Note that ftrace doesn't allow ftrace_ops which has IPMODIFY flag to have notrace hash, and the ftrace_ops must have a filter hash (so that the ftrace_ops can hook only specific entries), because it strongly depends on the address and must be allowed for only few selected functions. Link: http://lkml.kernel.org/r/20141121102516.11844.27829.stgit@localhost.localdomain Cc: Jiri Kosina <jkosina@suse.cz> Cc: Seth Jennings <sjenning@redhat.com> Cc: Petr Mladek <pmladek@suse.cz> Cc: Vojtech Pavlik <vojtech@suse.cz> Cc: Miroslav Benes <mbenes@suse.cz> Cc: Ingo Molnar <mingo@kernel.org> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> [ fixed up some of the comments ] Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-20tracing/trivial: Fix typos and make an int into a boolSteven Rostedt (Red Hat)
Fix up a few typos in comments and convert an int into a bool in update_traceon_count(). Link: http://lkml.kernel.org/r/546DD445.5080108@hitachi.com Suggested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-20Merge Linus' tree to be be to apply submitted patches to newer code thanJiri Kosina
current trivial.git base
2014-11-20kernel: trace: fix printk messageFrans Klaver
s,produciton,production Signed-off-by: Frans Klaver <frans.klaver@xsens.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2014-11-19seq_buf: Move the seq_buf code to lib/Steven Rostedt (Red Hat)
The seq_buf functions are rather useful outside of tracing. Instead of having it be dependent on CONFIG_TRACING, move the code into lib/ and allow other users to have access to it even when tracing is not configured. The seq_buf utility is similar to the seq_file utility, but instead of writing sending data back up to userland, it writes it into a buffer defined at seq_buf_init(). This allows us to send a descriptor around that writes printf() formatted strings into it that can be retrieved later. It is currently used by the tracing facility for such things like trace events to convert its binary saved data in the ring buffer into an ASCII human readable context to be displayed in /sys/kernel/debug/trace. It can also be used for doing NMI prints safely from NMI context into the seq_buf and retrieved later and dumped to printk() safely. Doing printk() from an NMI context is dangerous because an NMI can preempt a current printk() and deadlock on it. Link: http://lkml.kernel.org/p/20140619213952.058255809@goodmis.org Tested-by: Jiri Kosina <jkosina@suse.cz> Acked-by: Jiri Kosina <jkosina@suse.cz> Reviewed-by: Petr Mladek <pmladek@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-19seq-buf: Make seq_buf_bprintf() conditional on CONFIG_BINARY_PRINTFSteven Rostedt (Red Hat)
The function bstr_printf() from lib/vsprnintf.c is only available if CONFIG_BINARY_PRINTF is defined. This is due to the only user currently being the tracing infrastructure, which needs to select this config when tracing is configured. Until there is another user of the binary printf formats, this will continue to be the case. Since seq_buf.c is now lives in lib/ and is compiled even without tracing, it must encompass its use of bstr_printf() which is used by seq_buf_printf(). This too is only used by the tracing infrastructure and is still encapsulated by the CONFIG_BINARY_PRINTF. Link: http://lkml.kernel.org/r/20141104160222.969013383@goodmis.org Tested-by: Jiri Kosina <jkosina@suse.cz> Acked-by: Jiri Kosina <jkosina@suse.cz> Reviewed-by: Petr Mladek <pmladek@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-19tracing: Add seq_buf_get_buf() and seq_buf_commit() helper functionsSteven Rostedt (Red Hat)
Add two helper functions; seq_buf_get_buf() and seq_buf_commit() that are used by seq_buf_path(). This makes the code similar to the seq_file: seq_path() function, and will help to be able to consolidate the functions between seq_file and trace_seq. Link: http://lkml.kernel.org/r/20141104160222.644881406@goodmis.org Link: http://lkml.kernel.org/r/20141114011412.977571447@goodmis.org Tested-by: Jiri Kosina <jkosina@suse.cz> Acked-by: Jiri Kosina <jkosina@suse.cz> Reviewed-by: Petr Mladek <pmladek@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-19tracing: Have seq_buf use full bufferSteven Rostedt (Red Hat)
Currently seq_buf is full when all but one byte of the buffer is filled. Change it so that the seq_buf is full when all of the buffer is filled. Some of the functions would fill the buffer completely and report everything was fine. This was inconsistent with the max of size - 1. Changing this to be max of size makes all functions consistent. Link: http://lkml.kernel.org/r/20141104160222.502133196@goodmis.org Link: http://lkml.kernel.org/r/20141114011412.811957882@goodmis.org Tested-by: Jiri Kosina <jkosina@suse.cz> Acked-by: Jiri Kosina <jkosina@suse.cz> Reviewed-by: Petr Mladek <pmladek@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-19seq_buf: Add seq_buf_can_fit() helper functionSteven Rostedt (Red Hat)
Add a seq_buf_can_fit() helper function that removes the possible mistakes of comparing the seq_buf length plus added data compared to the size of the buffer. Link: http://lkml.kernel.org/r/20141118164025.GL23958@pathway.suse.cz Reviewed-by: Petr Mladek <pmladek@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-19tracing: Add paranoid size check in trace_printk_seq()Steven Rostedt (Red Hat)
To be really paranoid about writing out of bound data in trace_printk_seq(), add another check of len compared to size. Link: http://lkml.kernel.org/r/20141119144004.GB2332@dhcp128.suse.cz Suggested-by: Petr Mladek <pmladek@suse.cz> Reviewed-by: Petr Mladek <pmladek@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-19tracing: Use trace_seq_used() and seq_buf_used() instead of lenSteven Rostedt (Red Hat)
As the seq_buf->len will soon be +1 size when there's an overflow, we must use trace_seq_used() or seq_buf_used() methods to get the real length. This will prevent buffer overflow issues if just the len of the seq_buf descriptor is used to copy memory. Link: http://lkml.kernel.org/r/20141114121911.09ba3d38@gandalf.local.home Reported-by: Petr Mladek <pmladek@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-19tracing: Clean up tracing_fill_pipe_page()Steven Rostedt (Red Hat)
The function tracing_fill_pipe_page() logic is a little confusing with the use of count saving the seq.len and reusing it. Instead of subtracting a number that is calculated from the saved value of the seq.len from seq.len, just save the seq.len at the start and if we need to reset it, just assign it again. When the seq_buf overflow is len == size + 1, the current logic will break. Changing it to use a saved length for resetting back to the original value is more robust and will work when we change the way seq_buf sets the overflow. Link: http://lkml.kernel.org/r/20141118161546.GJ23958@pathway.suse.cz Reviewed-by: Petr Mladek <pmladek@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-19seq_buf: Create seq_buf_used() to find out how much was writtenSteven Rostedt (Red Hat)
Add a helper function seq_buf_used() that replaces the SEQ_BUF_USED() private macro to let callers have a method to know how much of the seq_buf was written to. Link: http://lkml.kernel.org/r/20141114011412.170377300@goodmis.org Link: http://lkml.kernel.org/r/20141114011413.321654244@goodmis.org Reviewed-by: Petr Mladek <pmladek@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-19tracing: Convert seq_buf_path() to be like seq_path()Steven Rostedt (Red Hat)
Rewrite seq_buf_path() like it is done in seq_path() and allow it to accept any escape character instead of just "\n". Making seq_buf_path() like seq_path() will help prevent problems when converting seq_file to use the seq_buf logic. Link: http://lkml.kernel.org/r/20141104160222.048795666@goodmis.org Link: http://lkml.kernel.org/r/20141114011412.338523371@goodmis.org Tested-by: Jiri Kosina <jkosina@suse.cz> Acked-by: Jiri Kosina <jkosina@suse.cz> Reviewed-by: Petr Mladek <pmladek@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-19tracing: Create seq_buf layer in trace_seqSteven Rostedt (Red Hat)
Create a seq_buf layer that trace_seq sits on. The seq_buf will not be limited to page size. This will allow other usages of seq_buf instead of a hard set PAGE_SIZE one that trace_seq has. Link: http://lkml.kernel.org/r/20141104160221.864997179@goodmis.org Link: http://lkml.kernel.org/r/20141114011412.170377300@goodmis.org Tested-by: Jiri Kosina <jkosina@suse.cz> Acked-by: Jiri Kosina <jkosina@suse.cz> Reviewed-by: Petr Mladek <pmladek@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-19tracing: Deletion of an unnecessary check before iput()Markus Elfring
The iput() function tests whether its argument is NULL and then returns immediately. Thus the test around the call is not needed. This issue was detected by using the Coccinelle software. Link: http://lkml.kernel.org/r/5468F875.7080907@users.sourceforge.net Signed-off-by: Markus Elfring <elfring@users.sourceforge.net> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-19tracing: Fix return value of ftrace_raw_output_prep()Steven Rostedt (Red Hat)
If the trace_seq of ftrace_raw_output_prep() is full this function returns TRACE_TYPE_PARTIAL_LINE, otherwise it returns zero. The problem is that TRACE_TYPE_PARTIAL_LINE happens to be zero! The thing is, the caller of ftrace_raw_output_prep() expects a success to be zero. Change that to expect it to be TRACE_TYPE_HANDLED. Link: http://lkml.kernel.org/r/20141114112522.GA2988@dhcp128.suse.cz Reminded-by: Petr Mladek <pmladek@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-19tracing: Remove return values of most trace_seq_*() functionsSteven Rostedt (Red Hat)
The trace_seq_printf() and friends are used to store strings into a buffer that can be passed around from function to function. If the trace_seq buffer fills up, it will not print any more. The return values were somewhat inconsistant and using trace_seq_has_overflowed() was a better way to know if the write to the trace_seq buffer succeeded or not. Now that all users have removed reading the return value of the printf() type functions, they can safely return void and keep future users of them from reading the inconsistent values as well. Link: http://lkml.kernel.org/r/20141114011411.992510720@goodmis.org Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-19tracing: Do not use return values of trace_seq_printf() in syscall tracingSteven Rostedt (Red Hat)
The functions trace_seq_printf() and friends will not be returning values soon and will be void functions. To know if they succeeded or not, the functions trace_seq_has_overflowed() and trace_handle_return() should be used instead. Reviewed-by: Petr Mladek <pmladek@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-19tracing/uprobes: Do not use return values of trace_seq_printf()Steven Rostedt (Red Hat)
The functions trace_seq_printf() and friends will soon no longer have return values. Using trace_seq_has_overflowed() and trace_handle_return() should be used instead. Link: http://lkml.kernel.org/r/20141114011411.693008134@goodmis.org Link: http://lkml.kernel.org/r/20141115050602.333705855@goodmis.org Reviewed-by: Masami Hiramatsu <masami.hiramatu.pt@hitachi.com> Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-19tracing/probes: Do not use return value of trace_seq_printf()Steven Rostedt (Red Hat)
The functions trace_seq_printf() and friends will soon not have a return value and will only be a void function. Use trace_seq_has_overflowed() instead to know if the trace_seq operations succeeded or not. Link: http://lkml.kernel.org/r/20141114011411.530216306@goodmis.org Reviewed-by: Petr Mladek <pmladek@suse.cz> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-19tracing: Do not check return values of trace_seq_p*() for mmio tracerSteven Rostedt (Red Hat)
The return values for trace_seq_printf() and friends are going to be removed and they will become void functions. The mmio tracer checked their return and even did so incorrectly. Some of the funtions which returned the values were never checked themselves. Removing all the checks simplifies the code. Use trace_seq_has_overflowed() and trace_handle_return() where necessary instead. Reviewed-by: Petr Mladek <pmladek@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-19kprobes/tracing: Use trace_seq_has_overflowed() for overflow checksSteven Rostedt (Red Hat)
Instead of checking the return value of trace_seq_printf() and friends for overflowing of the buffer, use the trace_seq_has_overflowed() helper function. This cleans up the code quite a bit and also takes us a step closer to changing the return values of trace_seq_printf() and friends to void. Link: http://lkml.kernel.org/r/20141114011411.181812785@goodmis.org Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Reviewed-by: Petr Mladek <pmladek@suse.cz> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-19tracing: Have function_graph use trace_seq_has_overflowed()Steven Rostedt (Red Hat)
Instead of doing individual checks all over the place that makes the code very messy. Just check trace_seq_has_overflowed() at the end or in strategic places. This makes the code much cleaner and also helps with getting closer to removing the return values of trace_seq_printf() and friends. Link: http://lkml.kernel.org/r/20141114011410.987913836@goodmis.org Reviewed-by: Petr Mladek <pmladek@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-19tracing: Have branch tracer use trace_handle_return() helper functionSteven Rostedt (Red Hat)
The branch tracer should not be checking the trace_seq_printf() return value as that will soon be void. There's a new trace_handle_return() helper function that will return TRACE_TYPE_PARTIAL_LINE if the trace_seq overflowed and TRACE_TYPE_HANDLED otherwise. Reviewed-by: Petr Mladek <pmladek@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-19ring-buffer: Remove check of trace_seq_{puts,printf}() return valuesSteven Rostedt (Red Hat)
Remove checking the return value of all trace_seq_puts(). It was wrong anyway as only the last return value mattered. But as the trace_seq_puts() is going to be a void function in the future, we should not be checking the return value of it anyway. Just return !trace_seq_has_overflowed() instead. Reviewed-by: Petr Mladek <pmladek@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-19blktrace/tracing: Use trace_seq_has_overflowed() helper functionSteven Rostedt (Red Hat)
Checking the return code of every trace_seq_printf() operation and having to return early if it overflowed makes the code messy. Using the new trace_seq_has_overflowed() and trace_handle_return() functions allows us to clean up the code. In the future, trace_seq_printf() and friends will be turning into void functions and not returning a value. The trace_seq_has_overflowed() is to be used instead. This cleanup allows that change to take place. Cc: Jens Axboe <axboe@fb.com> Reviewed-by: Petr Mladek <pmladek@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-19tracing: Add trace_seq_has_overflowed() and trace_handle_return()Steven Rostedt (Red Hat)
Adding a trace_seq_has_overflowed() which returns true if the trace_seq had too much written into it allows us to simplify the code. Instead of checking the return value of every call to trace_seq_printf() and friends, they can all be called normally, and at the end we can return !trace_seq_has_overflowed() instead. Several functions also return TRACE_TYPE_PARTIAL_LINE when the trace_seq overflowed and TRACE_TYPE_HANDLED otherwise. Another helper function was created called trace_handle_return() which takes a trace_seq and returns these enums. Using this helper function also simplifies the code. This change also makes it possible to remove the return values of trace_seq_printf() and friends. They should instead just be void functions. Link: http://lkml.kernel.org/r/20141114011410.365183157@goodmis.org Reviewed-by: Petr Mladek <pmladek@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-19tracing: Fix trace_seq_bitmask() to start at current positionSteven Rostedt (Red Hat)
In trace_seq_bitmask() it calls bitmap_scnprintf() not from the current position of the trace_seq buffer (s->buffer + s->len), but instead from the beginning of the buffer (s->buffer). Luckily, the only user of this "ipi_raise tracepoint" uses it as the first parameter, and as such, the start of the temp buffer in include/trace/ftrace.h (see __get_bitmask()). Reported-by: Petr Mladek <pmladek@suse.cz> Reviewed-by: Petr Mladek <pmladek@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-19ftrace/x86/extable: Add is_ftrace_trampoline() functionSteven Rostedt (Red Hat)
Stack traces that happen from function tracing check if the address on the stack is a __kernel_text_address(). That is, is the address kernel code. This calls core_kernel_text() which returns true if the address is part of the builtin kernel code. It also calls is_module_text_address() which returns true if the address belongs to module code. But what is missing is ftrace dynamically allocated trampolines. These trampolines are allocated for individual ftrace_ops that call the ftrace_ops callback functions directly. But if they do a stack trace, the code checking the stack wont detect them as they are neither core kernel code nor module address space. Adding another field to ftrace_ops that also stores the size of the trampoline assigned to it we can create a new function called is_ftrace_trampoline() that returns true if the address is a dynamically allocate ftrace trampoline. Note, it ignores trampolines that are not dynamically allocated as they will return true with the core_kernel_text() function. Link: http://lkml.kernel.org/r/20141119034829.497125839@goodmis.org Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-18tracing: Fix race of function probes countingSteven Rostedt (Red Hat)
The function probe counting for traceon and traceoff suffered a race condition where if the probe was executing on two or more CPUs at the same time, it could decrement the counter by more than one when disabling (or enabling) the tracer only once. The way the traceon and traceoff probes are suppose to work is that they disable (or enable) tracing once per count. If a user were to echo 'schedule:traceoff:3' into set_ftrace_filter, then when the schedule function was called, it would disable tracing. But the count should only be decremented once (to 2). Then if the user enabled tracing again (via tracing_on file), the next call to schedule would disable tracing again and the count would be decremented to 1. But if multiple CPUS called schedule at the same time, it is possible that the count would be decremented more than once because of the simple "count--" used. By reading the count into a local variable and using memory barriers we can guarantee that the count would only be decremented once per disable (or enable). The stack trace probe had a similar race, but here the stack trace will decrement for each time it is called. But this had the read-modify- write race, where it could stack trace more than the number of times that was specified. This case we use a cmpxchg to stack trace only the number of times specified. The dump probes can still use the old "update_count()" function as they only run once, and that is controlled by the dump logic itself. Link: http://lkml.kernel.org/r/20141118134643.4b550ee4@gandalf.local.home Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-14function_graph: Fix micro seconds notationsByungchul Park
Usually, "msecs" notation means milli-seconds, and "usecs" notation means micro-seconds. Since the unit used in the code is micro-seconds, the notation should be replaced from msecs to usecs. Link: http://lkml.kernel.org/r/1415171926-9782-2-git-send-email-byungchul.park@lge.com Signed-off-by: Byungchul Park <byungchul.park@lge.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-14ftrace-graph: show latency-format on print_graph_irq()Daniel Bristot de Oliveira
On the function_graph tracer, the print_graph_irq() function prints a trace line with the flag ==========> on an irq handler entry, and the flag <========== on an irq handler return. But when the latency-format is enable, it is not printing the latency-format flags, causing the following error in the trace output: 0) ==========> | 0) d... | smp_apic_timer_interrupt() { This patch fixes this issue by printing the latency-format flags when it is enable. Link: http://lkml.kernel.org/r/7c2e226dac20c940b6242178fab7f0e3c9b5ce58.1415233316.git.bristot@redhat.com Reviewed-by: Luis Claudio R. Goncalves <lgoncalv@redhat.com> Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-14trace: Replace single-character seq_puts with seq_putcRasmus Villemoes
Printing a single character to a seqfile might as well be done with seq_putc instead of seq_puts; this avoids a strlen() call and a memory access. It also shaves another few bytes off the generated code. Link: http://lkml.kernel.org/r/1415479332-25944-4-git-send-email-linux@rasmusvillemoes.dk Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-13tracing: Merge consecutive seq_puts callsRasmus Villemoes
Consecutive seq_puts calls with literal strings can be merged to a single call. This reduces the size of the generated code, and can also lead to slight .rodata reduction (because of fewer nul and padding bytes). It should also shave a off a few clock cycles. Link: http://lkml.kernel.org/r/1415479332-25944-3-git-send-email-linux@rasmusvillemoes.dk Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>