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* s390/cpum_sf: prohibit callchain data collectionThomas Richter2020-07-011-1/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | CPU Measurement sampling facility on s390 does not support perf tool collection of callchain data using --call-graph option. The sampling facility collects samples in a ring buffer which includes only the instruction address the samples were taken. When the ring buffer hits a watermark, a measurement alert interrupt is triggered and handled by the performance measurement unit (PMU) device driver. It collects the samples and feeds each sample to the perf ring buffer in the common code via functions perf_prepare_sample()/perf_output_sample(). When function perf_prepare_sample() is called to collect sample data's callchain, user register values or stack area, invalid data is picked, because the context of the collected information does not match the context when the sample was taken. There is currently no way to provide the callchain and other information, because the hardware sampler does not collect this information. Therefore prohibit sampling when the user requests a callchain graph from the hardware sampler. Return -EOPNOTSUPP to the user in this case. If call chains are really wanted, users need to specify software event cpu-clock to get the callchain information from a software event. Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Reviewed-by: Sumanth Korikkar <sumanthk@linux.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
* s390/cpum_sf: Fix wrong page count in error messageThomas Richter2020-03-251-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | When perf record -e SF_CYCLES_BASIC_DIAG runs with very high frequency, the samples arrive faster than the perf process can save them to file. Eventually, for longer running processes, this leads to the siutation where the trace buffers allocated by perf slowly fills up. At one point the auxiliary trace buffer is full and the CPU Measurement sampling facility is turned off. Furthermore a warning is printed to the kernel log buffer: cpum_sf: The AUX buffer with 0 pages for the diagnostic-sampling mode is full The number of allocated pages for the auxiliary trace buffer is shown as zero pages. That is wrong. Fix this by saving the number of allocated pages before entering the work loop in the interrupt handler. When the interrupt handler processes the samples, it may detect the buffer full condition and stop sampling, reducing the buffer size to zero. Print the correct value in the error message: cpum_sf: The AUX buffer with 256 pages for the diagnostic-sampling mode is full Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
* s390/cpum_sf: Rework sampling buffer allocationThomas Richter2020-02-171-19/+21
| | | | | | | | | | | | | | | | | | | | | | | Adjust sampling buffer allocation depending on frequency and correct comments. Investigation on the interrupt handler revealed that almost always one interupt services one SDB, even when running with the maximum frequency of 100000. Very rarely there have been 2 SBD serviced per interrupt. Therefore reduce the number of SBD per CPU. Each SDB is one page in size. The new formula results in freq:4000 n_sdb:32 new:16 freq:10000 n_sdb:80 new:16 freq:20000 n_sdb:159 new:17 freq:40000 n_sdb:318 new:19 freq:50000 n_sdb:397 new:20 freq:62500 n_sdb:497 new:22 freq:83333 n_sdb:662 new:24 freq:100000 n_sdb:794 new:25 Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
* s390/cpum_sf: Use DIV_ROUND_UPThomas Richter2020-01-221-1/+1
| | | | | | | | | Use macro DIV_ROUND_UP() for calculation of number of SDBT SDBT pages required for index pages. This macro is already used throughout the file. Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
* s390/cpum_sf: Use kzalloc and minor changesThomas Richter2020-01-221-5/+4
| | | | | | | | | | Use kzalloc() to allocate auxiliary buffer structure initialized with all zeroes to avoid random value in trace output. Avoid double access to SBD hardware flags. Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
* s390/cpum_sf: Convert debug trace to common layoutThomas Richter2020-01-221-26/+30
| | | | | | | | | Convert debug traces to print the head/alert/empty marks consistently as decimal numbers. Add some trace statements to enable easier debugging during auxiliary tracing. Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
* s390/cpum_sf: Avoid SBD overflow condition in irq handlerThomas Richter2019-12-111-6/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The s390 CPU Measurement sampling facility has an overflow condition which fires when all entries in a SBD are used. The measurement alert interrupt is triggered and reads out all samples in this SDB. It then tests the successor SDB, if this SBD is not full, the interrupt handler does not read any samples at all from this SDB The design waits for the hardware to fill this SBD and then trigger another meassurement alert interrupt. This scheme works nicely until an perf_event_overflow() function call discards the sample due to a too high sampling rate. The interrupt handler has logic to read out a partially filled SDB when the perf event overflow condition in linux common code is met. This causes the CPUM sampling measurement hardware and the PMU device driver to operate on the same SBD's trailer entry. This should not happen. This can be seen here using this trace: cpumsf_pmu_add: tear:0xb5286000 hw_perf_event_update: sdbt 0xb5286000 full 1 over 0 flush_all:0 hw_perf_event_update: sdbt 0xb5286008 full 0 over 0 flush_all:0 above shows 1. interrupt hw_perf_event_update: sdbt 0xb5286008 full 1 over 0 flush_all:0 hw_perf_event_update: sdbt 0xb5286008 full 0 over 0 flush_all:0 above shows 2. interrupt ... this goes on fine until... hw_perf_event_update: sdbt 0xb5286068 full 1 over 0 flush_all:0 perf_push_sample1: overflow one or more samples read from the IRQ handler are rejected by perf_event_overflow() and the IRQ handler advances to the next SDB and modifies the trailer entry of a partially filled SDB. hw_perf_event_update: sdbt 0xb5286070 full 0 over 0 flush_all:1 timestamp: 14:32:52.519953 Next time the IRQ handler is called for this SDB the trailer entry shows an overflow count of 19 missed entries. hw_perf_event_update: sdbt 0xb5286070 full 1 over 19 flush_all:1 timestamp: 14:32:52.970058 Remove access to a follow on SDB when event overflow happened. Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
* s390/cpum_sf: Adjust sampling interval to avoid hitting sample limitsThomas Richter2019-12-111-0/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Function perf_event_ever_overflow() and perf_event_account_interrupt() are called every time samples are processed by the interrupt handler. However function perf_event_account_interrupt() has checks to avoid being flooded with interrupts (more then 1000 samples are received per task_tick). Samples are then dropped and a PERF_RECORD_THROTTLED is added to the perf data. The perf subsystem limit calculation is: maximum sample frequency := 100000 --> 1 samples per 10 us task_tick = 10ms = 10000us --> 1000 samples per task_tick The work flow is measurement_alert() uses SDBT head and each SBDT points to 511 SDB pages, each with 126 sample entries. After processing 8 SBDs and for each valid sample calling: perf_event_overflow() perf_event_account_interrupts() there is a considerable amount of samples being dropped, especially when the sample frequency is very high and near the 100000 limit. To avoid the high amount of samples being dropped near the end of a task_tick time frame, increment the sampling interval in case of dropped events. The CPU Measurement sampling facility on the s390 supports only intervals, specifiing how many CPU cycles have to be executed before a sample is generated. Increase the interval when the samples being generated hit the task_tick limit. Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
* s390/cpum_sf: Check for SDBT and SDB consistencyThomas Richter2019-11-301-2/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Each SBDT is located at a 4KB page and contains 512 entries. Each entry of a SDBT points to a SDB, a 4KB page containing sampled data. The last entry is a link to another SDBT page. When an event is created the function sequence executed is: __hw_perf_event_init() +--> allocate_buffers() +--> realloc_sampling_buffers() +---> alloc_sample_data_block() Both functions realloc_sampling_buffers() and alloc_sample_data_block() allocate pages and the allocation can fail. This is handled correctly and all allocated pages are freed and error -ENOMEM is returned to the top calling function. Finally the event is not created. Once the event has been created, the amount of initially allocated SDBT and SDB can be too low. This is detected during measurement interrupt handling, where the amount of lost samples is calculated. If the number of lost samples is too high considering sampling frequency and already allocated SBDs, the number of SDBs is enlarged during the next execution of cpumsf_pmu_enable(). If more SBDs need to be allocated, functions realloc_sampling_buffers() +---> alloc-sample_data_block() are called to allocate more pages. Page allocation may fail and the returned error is ignored. A SDBT and SDB setup already exists. However the modified SDBTs and SDBs might end up in a situation where the first entry of an SDBT does not point to an SDB, but another SDBT, basicly an SBDT without payload. This can not be handled by the interrupt handler, where an SDBT must have at least one entry pointing to an SBD. Add a check to avoid SDBTs with out payload (SDBs) when enlarging the buffer setup. Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
* s390/cpum_sf: Use TEAR_REG macro consistantlyThomas Richter2019-11-301-8/+1
| | | | | | | | | | | | | The macro TEAR_REG() saves the last used SDBT address in the perf_hw_event structure. This is also done by function hw_reset_registers() which is a one-liner and simply uses macro TEAR_REG(). Remove function hw_reset_registers(), which is only used one time and use macro TEAR_REG() instead. This macro is used throughout the code anyway. Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
* s390/cpum_sf: Remove unnecessary check for pending SDBsThomas Richter2019-11-301-2/+1
| | | | | | | | | | In interrupt handling the function extend_sampling_buffer() is called after checking for a possibly extension. This check is not necessary as the called function itself performs this check again. Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
* s390/cpum_sf: Replace function name in debug statementsThomas Richter2019-11-301-51/+56
| | | | | | | | | | | | Replace hard coded function names in debug statements by the "%s ...", __func__ construct suggested by checkpatch.pl script. Use consistent debug print format of the form variable blank value. Also add leading 0x for all hex values. Print allocated page addresses consistantly as hex numbers with leading 0x. Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
* s390/cpum_sf: Assign error value to err variableThomas Richter2019-11-121-1/+2
| | | | | | | | | | | | When starting the CPU Measurement sampling facility using qsi() function, this function may return an error value. This error value is referenced in the else part of the if statement to dump its value in a debug statement. Right now this value is always zero because it has not been assigned a value. Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
* s390/cpum_sf: Replace function name in debug statementsThomas Richter2019-11-121-15/+15
| | | | | | | | | Replace hard coded function names in debug statements by the "%s ...", __func__ construct suggested by checkpatch.pl script. Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
* s390/cpum_sf: Use consistant debug print format for samplingThomas Richter2019-11-121-47/+44
| | | | | | | | Use consistant debug print format of the form variable blank value. Also add leading 0x for all hex values. Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
* s390/cpumf: Fix indentation in sampling device driverThomas Richter2019-10-011-1/+1
| | | | | | | | Fix indentation in the s390 CPU Measuement Facility sampling device dirver. Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
* s390/cpumsf: Check for CPU Measurement samplingThomas Richter2019-10-011-0/+6
| | | | | | | | | | s390 IBM z15 introduces a check if the CPU Mesurement Facility sampling is temporarily unavailable. If this is the case return -EBUSY and abort the setup of CPU Measuement facility sampling. Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
* s390/cpum_sf: Support ioctl PERF_EVENT_IOC_PERIODThomas Richter2019-09-191-40/+125
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A perf_event can be set up to deliver overflow notifications via SIGIO signal. The setup of the event is: 1. create event with perf_event_open() 2. assign it a signal for I/O notification with fcntl() 3. Install signal handler and consume samples The initial setup of perf_event_open() determines the period/frequency time span needed to elapse before each signal is delivered to the user process. While the event is active, system call ioctl(.., PERF_EVENT_IOC_PERIOD, value) can be used the change the frequency/period time span of the active event. The remaining signal handler invocations honour the new value. This does not work on s390. In fact the time span does not change regardless of ioctl's third argument 'value'. The call succeeds but the time span does not change. Support this behavior and make it common with other platforms. This is achieved by changing the interval value of the sampling control block accordingly and feed this new value every time the event is enabled using pmu_event_enable(). Before this change the interval value was set only once at pmu_event_add() and never changed. Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
* s390/cpum_sf: Fix line length and format stringThomas Richter2019-09-161-7/+13
| | | | | | | | | Rewrite some lines to match line length and replace format string 0x%x to %#x. Add and remove blank line. Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Reviewed-by: Hendrik Brueckner <brueckner@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
* perf/aux: Make perf_event accessible to setup_aux()Mathieu Poirier2019-02-061-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | When pmu::setup_aux() is called the coresight PMU needs to know which sink to use for the session by looking up the information in the event's attr::config2 field. As such simply replace the cpu information by the complete perf_event structure and change all affected customers. Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Reviewed-by: Suzuki Poulouse <suzuki.poulose@arm.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-s390@vger.kernel.org Link: http://lkml.kernel.org/r/20190131184714.20388-2-mathieu.poirier@linaro.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* s390/cpum_sf: Rework attribute definition for diagnostic samplingThomas Richter2018-11-021-5/+28
| | | | | | | | | | | | | | | Previously, the attribute entry for diagnostic sampling was added if authorized. Otherwise, the array of struct attribute contains two NULL values. Change this logic and reserve space for the attribute for diagnostic sampling. If diagnostic sampling is authorized, add an entry in the respective position in the array of struct attribute. Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Reviewed-by: Hendrik Brueckner <brueckner@linux.ibm.com> Suggested-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/perf: Return error when debug_register failsThomas Richter2018-10-191-1/+5
| | | | | | | | | | | Return an error when the function debug_register() fails allocating the debug handle. Also remove the registered debug handle when the initialization fails later on. Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Reviewed-by: Hendrik Brueckner <brueckner@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* Merge branch 'siginfo-linus' of ↵Linus Torvalds2018-08-211-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull core signal handling updates from Eric Biederman: "It was observed that a periodic timer in combination with a sufficiently expensive fork could prevent fork from every completing. This contains the changes to remove the need for that restart. This set of changes is split into several parts: - The first part makes PIDTYPE_TGID a proper pid type instead something only for very special cases. The part starts using PIDTYPE_TGID enough so that in __send_signal where signals are actually delivered we know if the signal is being sent to a a group of processes or just a single process. - With that prep work out of the way the logic in fork is modified so that fork logically makes signals received while it is running appear to be received after the fork completes" * 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (22 commits) signal: Don't send signals to tasks that don't exist signal: Don't restart fork when signals come in. fork: Have new threads join on-going signal group stops fork: Skip setting TIF_SIGPENDING in ptrace_init_task signal: Add calculate_sigpending() fork: Unconditionally exit if a fatal signal is pending fork: Move and describe why the code examines PIDNS_ADDING signal: Push pid type down into complete_signal. signal: Push pid type down into __send_signal signal: Push pid type down into send_signal signal: Pass pid type into do_send_sig_info signal: Pass pid type into send_sigio_to_task & send_sigurg_to_task signal: Pass pid type into group_send_sig_info signal: Pass pid and pid type into send_sigqueue posix-timers: Noralize good_sigevent signal: Use PIDTYPE_TGID to clearly store where file signals will be sent pid: Implement PIDTYPE_TGID pids: Move the pgrp and session pid pointers from task_struct to signal_struct kvm: Don't open code task_pid in kvm_vcpu_ioctl pids: Compute task_tgid using signal->leader_pid ...
| * pid: Implement PIDTYPE_TGIDEric W. Biederman2018-07-211-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Everywhere except in the pid array we distinguish between a tasks pid and a tasks tgid (thread group id). Even in the enumeration we want that distinction sometimes so we have added __PIDTYPE_TGID. With leader_pid we almost have an implementation of PIDTYPE_TGID in struct signal_struct. Add PIDTYPE_TGID as a first class member of the pid_type enumeration and into the pids array. Then remove the __PIDTYPE_TGID special case and the leader_pid in signal_struct. The net size increase is just an extra pointer added to struct pid and an extra pair of pointers of an hlist_node added to task_struct. The effect on code maintenance is the removal of a number of special cases today and the potential to remove many more special cases as PIDTYPE_TGID gets used to it's fullest. The long term potential is allowing zombie thread group leaders to exit, which will remove a lot more special cases in the code. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
* | s390/cpum_sf: save TOD clock base in SDBs for time conversionHendrik Brueckner2018-07-311-1/+13
|/ | | | | | | | | | | | Processing the samples in the AUX-area by perf requires the computation of respective time stamps. The time stamps used by perf are based on the monotonic clock. To convert the TOD clock value contained in an SDB to a monotonic clock value, the TOD clock base is required. Hence, also save the TOD clock base in the SDB. Suggested-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Hendrik Brueckner <brueckner@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/cpum_sf: ensure sample frequency of perf event attributes is non-zeroHendrik Brueckner2018-05-081-0/+4
| | | | | | | | | | | | | Correct a trinity finding for the perf_event_open() system call with a perf event attribute structure that uses a frequency but has the sampling frequency set to zero. This causes a FP divide exception during the sample rate initialization for the hardware sampling facility. Fixes: 8c069ff4bd606 ("s390/perf: add support for the CPU-Measurement Sampling Facility") Cc: stable@vger.kernel.org # 3.14+ Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Hendrik Brueckner <brueckner@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390: kernel: Remove redundant license textGreg Kroah-Hartman2017-11-241-4/+0
| | | | | | | | | | | | | | | | | | | | | | | | | Now that the SPDX tag is in all arch/s390/kernel/ files, that identifies the license in a specific and legally-defined manner. So the extra GPL text wording can be removed as it is no longer needed at all. This is done on a quest to remove the 700+ different ways that files in the kernel describe the GPL license text. And there's unneeded stuff like the address (sometimes incorrect) for the FSF which is never needed. No copyright headers or other non-license-description text was removed. Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390: kernel: add SPDX identifiers to the remaining filesGreg Kroah-Hartman2017-11-241-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | It's good to have SPDX identifiers in all files to make it easier to audit the kernel tree for correct licenses. Update the arch/s390/kernel/ files with the correct SPDX license identifier based on the license text in the file itself. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This work is based on a script and data from Thomas Gleixner, Philippe Ombredanne, and Kate Stewart. Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Kate Stewart <kstewart@linuxfoundation.org> Cc: Philippe Ombredanne <pombredanne@nexb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/cpum_sf: correctly set the PID and TID in perf samplesHendrik Brueckner2017-11-161-0/+76
| | | | | | | | | | | | | | | | | | | | | | | | | The hardware sampler creates samples that are processed at a later point in time. The PID and TID values of the perf samples that are created for hardware samples are initialized with values from the current task. Hence, the PID and TID values are not correct and perf samples are associated with wrong processes. The PID and TID values are obtained from the Host Program Parameter (HPP) field in the basic-sampling data entries. These PIDs are valid in the init PID namespace. Ensure that the PIDs in the perf samples are resolved considering the PID namespace in which the perf event was created. To correct the PID and TID values in the created perf samples, a special overflow handler is installed. It replaces the default overflow handler and does not become effective if any other overflow handler is used. With the special overflow handler most of the perf samples are associated with the right processes. For processes, that are no longer exist, the association might still be wrong. Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/cpum_sf: load program parameter at sampler enablementHendrik Brueckner2017-11-161-0/+3
| | | | | | | | | | | | | | | | | | | | The lpp instruction is used to place the PID of the current task in the program-parameter (PP) register. The register contents is then included in the sampling data entries. The lpp instruction loads the PP register only when at least one sampling function is enabled. Otherwise it is executed as a no-op. Linux calls lpp at context switch. If the context switch happens before the sampler is enabled, the PP register is empty. That means, the PID of the task that is sampled is not stored in sampling data until the next context switch. Hence, always call lpp when enabling the sampler. Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/cpum_sf: do not register PMU if no sampling mode is authorizedHendrik Brueckner2017-11-161-0/+3
| | | | | | | | | Previously, the cpum_sf PMU was registered even if there is no sampling mode authorized. Add a check and register cpum_sf only at least one sampling mode is authorized. Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/cpumf: remove raw event support in basic-only sampling modePu Hou2017-11-161-158/+27
| | | | | | | | | | | Raw sample was implemented to export the diagnostic samples. With having this achieved with AUX buffers, there is no requirement for basic samples to export raw data. In particular, most basic sampling information are consumed for creating the perf event sample. Signed-off-by: Pu Hou <bjhoupu@linux.vnet.ibm.com> Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/cpumf: enable using AUX bufferPu Hou2017-11-161-11/+44
| | | | | | | | | Modify PMU callback to use AUX buffer for diagnostic mode sampling. Basic-mode sampling still use orignal way. Signed-off-by: Pu Hou <bjhoupu@linux.vnet.ibm.com> Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/cpumf: introduce AUX buffer for dump diagnostic sample dataPu Hou2017-11-161-0/+446
| | | | | | | | | | | | | | | | | Current implementation uses a private buffer for cpumf to dump samples. Samples first go to this buffer. Then copy to ring buffer allocated by perf core. With AUX buffer, this copy is not needed. AUX buffer is shared and zero-copy mapped to user space. The trailer information at the end of each SDB(sample data block) is also exported to user space. AUX buffer is used when diagnostic sampling mode is enabled. This patch contains functions to setup/free AUX buffer or to begin/end sampling per-cpu. Also include function called in interrupt to collect samples. Signed-off-by: Pu Hou <bjhoupu@linux.vnet.ibm.com> Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/cpumf: remove superfluous nr_cpumask_bits checkHeiko Carstens2017-09-281-5/+1
| | | | | | | | | | | | Paul Burton reported that the nr_cpumask_bits check within cpumsf_pmu_event_init() is not necessary. Actually there is already a prior check within perf_event_alloc(). Therefore remove the check. Reported-by: Paul Burton <paul.burton@imgtec.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/perf: fix bug when creating per-thread eventPu Hou2017-09-131-3/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | A per-thread event could not be created correctly like below: perf record --per-thread -e rB0000 -- sleep 1 Error: The sys_perf_event_open() syscall returned with 19 (No such device) for event (rB0000). /bin/dmesg may provide additional information. No CONFIG_PERF_EVENTS=y kernel support configured? This bug was introduced by: commit c311c797998c1e70eade463dd60b843da4f1a203 Author: Alexey Dobriyan <adobriyan@gmail.com> Date: Mon May 8 15:56:15 2017 -0700 cpumask: make "nr_cpumask_bits" unsigned If a per-thread event is not attached to any CPU, the cpu field in struct perf_event is -1. The above commit converts the CPU number to unsigned int, which result in an illegal CPU number. Fixes: c311c797998c ("cpumask: make "nr_cpumask_bits" unsigned") Cc: <stable@vger.kernel.org> # v4.12+ Cc: Alexey Dobriyan <adobriyan@gmail.com> Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Pu Hou <bjhoupu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/perf: fix problem state detectionChristian Borntraeger2017-07-131-1/+1
| | | | | | | | | The P sample bit indicates problem state and not PER. Fixes: commit a752598254 ("s390: rename struct psw_bits members") Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390: rename struct psw_bits membersHeiko Carstens2017-06-121-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | Rename a couple of the struct psw_bits members so it is more obvious for what they are good. Initially I thought using the single character names from the PoP would be sufficient and obvious, but admittedly that is not true. The current implementation is not easy to use, if one has to look into the source file to figure out which member represents the 'per' bit (which is the 'r' member). Therefore rename the members to sane names that are identical to the uapi psw mask defines: r -> per i -> io e -> ext t -> dat m -> mcheck w -> wait p -> pstate Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* cpumask: make "nr_cpumask_bits" unsignedAlexey Dobriyan2017-05-081-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Bit searching functions accept "unsigned long" indices but "nr_cpumask_bits" is "int" which is signed, so inevitable sign extensions occur on x86_64. Those MOVSX are #1 MOVSX bloat by number of uses across whole kernel. Change "nr_cpumask_bits" to unsigned, this number can't be negative after all. It allows to do implicit zero-extension on x86_64 without MOVSX. Change signed comparisons into unsigned comparisons where necessary. Other uses looks fine because it is either argument passed to a function or comparison is already unsigned. Net win on allyesconfig type of kernel: ~2.8 KB (!) add/remove: 0/0 grow/shrink: 8/725 up/down: 93/-2926 (-2833) function old new delta xen_exit_mmap 691 735 +44 qstat_read 426 440 +14 __cpufreq_cooling_register 1678 1687 +9 trace_rb_cpu_prepare 447 455 +8 vermagic 54 60 +6 nfp_driver_version 54 60 +6 rcu_torture_stats_print 1147 1151 +4 find_next_push_cpu 267 269 +2 xen_irq_resume 961 960 -1 ... init_vp_index 946 906 -40 od_set_powersave_bias 328 281 -47 power_cpu_exit 193 139 -54 arch_show_interrupts 3538 3484 -54 select_idle_sibling 1558 1471 -87 Total: Before=158358910, After=158356077, chg -0.00% Same arguments apply to "nr_cpu_ids" but I haven't yet found enough courage to delve into this issue (and proper fix may require new type "cpu_t" which is whole separate story). Link: http://lkml.kernel.org/r/20170309205322.GA1728@avx2 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* s390/cpumf: simplify detection of guest samplesMartin Schwidefsky2017-04-051-4/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are three different code levels in regard to the identification of guest samples. They differ in the way the LPP instruction is used. 1) Old kernels without the LPP instruction. The guest program parameter is always zero. 2) Newer kernels load the process pid into the program parameter with LPP. The guest program parameter is non-zero if the guest executes in a process != idle. 3) The latest kernels load ((1UL << 31) | pid) with LPP to make the value non-zero even for the idle task. The guest program parameter is non-zero if the guest is running. All kernels load the process pid to CR4 on context switch. The CPU sampling code uses the value in CR4 to decide between guest and host samples in case the guest program parameter is zero. The three cases: 1) CR4==pid, gpp==0 2) CR4==pid, gpp==pid 3) CR4==pid, gpp==((1UL << 31) | pid) The load-control instruction to load the pid into CR4 is expensive and the goal is to remove it. To distinguish the host CR4 from the guest pid for the idle process the maximum value 0xffff for the PASN is used. This adds a fourth case for a guest OS with an updated kernel: 4) CR4==0xffff, gpp=((1UL << 31) | pid) The host kernel will have CR4==0xffff and will use (gpp!=0 || CR4!==0xffff) to identify guest samples. This works nicely with all 4 cases, the only possible issue would be a guest with an old kernel (gpp==0) and a process pid of 0xffff. Well, don't do that.. Suggested-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* cpu/hotplug: Cleanup state namesThomas Gleixner2016-12-251-1/+1
| | | | | | | | | | | | | | | | | When the state names got added a script was used to add the extra argument to the calls. The script basically converted the state constant to a string, but the cleanup to convert these strings into meaningful ones did not happen. Replace all the useless strings with 'subsys/xxx/yyy:state' strings which are used in all the other places already. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sebastian Siewior <bigeasy@linutronix.de> Link: http://lkml.kernel.org/r/20161221192112.085444152@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* s390/cpumf: Use configuration level indication for sampling dataChristian Borntraeger2016-12-121-7/+20
| | | | | | | | | | | Newer hardware provides the level of virtualization that a particular sample belongs to. Use that information and fall back to the old heuristics if the sample does not contain that information. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/cpumf: simplify psw generationHeiko Carstens2016-11-231-21/+5
| | | | | | | | | Use the psw_bits macro and simplify the code. The generated code is also better since it doesn't contain any conditional branches anymore. Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* Merge branch 'smp-hotplug-for-linus' of ↵Linus Torvalds2016-07-291-26/+19
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull smp hotplug updates from Thomas Gleixner: "This is the next part of the hotplug rework. - Convert all notifiers with a priority assigned - Convert all CPU_STARTING/DYING notifiers The final removal of the STARTING/DYING infrastructure will happen when the merge window closes. Another 700 hundred line of unpenetrable maze gone :)" * 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (70 commits) timers/core: Correct callback order during CPU hot plug leds/trigger/cpu: Move from CPU_STARTING to ONLINE level powerpc/numa: Convert to hotplug state machine arm/perf: Fix hotplug state machine conversion irqchip/armada: Avoid unused function warnings ARC/time: Convert to hotplug state machine clocksource/atlas7: Convert to hotplug state machine clocksource/armada-370-xp: Convert to hotplug state machine clocksource/exynos_mct: Convert to hotplug state machine clocksource/arm_global_timer: Convert to hotplug state machine rcu: Convert rcutree to hotplug state machine KVM/arm/arm64/vgic-new: Convert to hotplug state machine smp/cfd: Convert core to hotplug state machine x86/x2apic: Convert to CPU hotplug state machine profile: Convert to hotplug state machine timers/core: Convert to hotplug state machine hrtimer: Convert to hotplug state machine x86/tboot: Convert to hotplug state machine arm64/armv8 deprecated: Convert to hotplug state machine hwtracing/coresight-etm4x: Convert to hotplug state machine ...
| * s390/perf: Convert the hotplug notifier to state machine callbacks (Sampling)Sebastian Andrzej Siewior2016-07-141-26/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Install the callbacks via the state machine and let the core invoke the callbacks on the already online CPUs. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-s390@vger.kernel.org Cc: rt@linutronix.de Link: http://lkml.kernel.org/r/20160713153334.518084858@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds2016-07-271-3/+6
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull networking updates from David Miller: 1) Unified UDP encapsulation offload methods for drivers, from Alexander Duyck. 2) Make DSA binding more sane, from Andrew Lunn. 3) Support QCA9888 chips in ath10k, from Anilkumar Kolli. 4) Several workqueue usage cleanups, from Bhaktipriya Shridhar. 5) Add XDP (eXpress Data Path), essentially running BPF programs on RX packets as soon as the device sees them, with the option to mirror the packet on TX via the same interface. From Brenden Blanco and others. 6) Allow qdisc/class stats dumps to run lockless, from Eric Dumazet. 7) Add VLAN support to b53 and bcm_sf2, from Florian Fainelli. 8) Simplify netlink conntrack entry layout, from Florian Westphal. 9) Add ipv4 forwarding support to mlxsw spectrum driver, from Ido Schimmel, Yotam Gigi, and Jiri Pirko. 10) Add SKB array infrastructure and convert tun and macvtap over to it. From Michael S Tsirkin and Jason Wang. 11) Support qdisc packet injection in pktgen, from John Fastabend. 12) Add neighbour monitoring framework to TIPC, from Jon Paul Maloy. 13) Add NV congestion control support to TCP, from Lawrence Brakmo. 14) Add GSO support to SCTP, from Marcelo Ricardo Leitner. 15) Allow GRO and RPS to function on macsec devices, from Paolo Abeni. 16) Support MPLS over IPV4, from Simon Horman. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1622 commits) xgene: Fix build warning with ACPI disabled. be2net: perform temperature query in adapter regardless of its interface state l2tp: Correctly return -EBADF from pppol2tp_getname. net/mlx5_core/health: Remove deprecated create_singlethread_workqueue net: ipmr/ip6mr: update lastuse on entry change macsec: ensure rx_sa is set when validation is disabled tipc: dump monitor attributes tipc: add a function to get the bearer name tipc: get monitor threshold for the cluster tipc: make cluster size threshold for monitoring configurable tipc: introduce constants for tipc address validation net: neigh: disallow transition to NUD_STALE if lladdr is unchanged in neigh_update() MAINTAINERS: xgene: Add driver and documentation path Documentation: dtb: xgene: Add MDIO node dtb: xgene: Add MDIO node drivers: net: xgene: ethtool: Use phy_ethtool_gset and sset drivers: net: xgene: Use exported functions drivers: net: xgene: Enable MDIO driver drivers: net: xgene: Add backward compatibility drivers: net: phy: xgene: Add MDIO driver ...
| * | perf, events: add non-linear data support for raw recordsDaniel Borkmann2016-07-151-3/+6
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds support for non-linear data on raw records. It extends raw records to have one or multiple fragments that will be written linearly into the ring slot, where each fragment can optionally have a custom callback handler to walk and extract complex, possibly non-linear data. If a callback handler is provided for a fragment, then the new __output_custom() will be used instead of __output_copy() for the perf_output_sample() part. perf_prepare_sample() does all the size calculation only once, so perf_output_sample() doesn't need to redo the same work anymore, meaning real_size and padding will be cached in the raw record. The raw record becomes 32 bytes in size without holes; to not increase it further and to avoid doing unnecessary recalculations in fast-path, we can reuse next pointer of the last fragment, idea here is borrowed from ZERO_OR_NULL_PTR(), which should keep the perf_output_sample() path for PERF_SAMPLE_RAW minimal. This facility is needed for BPF's event output helper as a first user that will, in a follow-up, add an additional perf_raw_frag to its perf_raw_record in order to be able to more efficiently dump skb context after a linear head meta data related to it. skbs can be non-linear and thus need a custom output function to dump buffers. Currently, the skb data needs to be copied twice; with the help of __output_custom() this work only needs to be done once. Future users could be things like XDP/BPF programs that work on different context though and would thus also have a different callback function. The few users of raw records are adapted to initialize their frag data from the raw record itself, no change in behavior for them. The code is based upon a PoC diff provided by Peter Zijlstra [1]. [1] http://thread.gmane.org/gmane.linux.network/421294 Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* / s390/perf: remove perf_release/reserver_sampling functionsHeiko Carstens2016-06-281-5/+0
|/ | | | | | | | | | Now that the oprofile sampling code is gone there is only one user of the sampling facility left. Therefore the reserve and release functions can be removed. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/cpum_sf: Remove superfluous SMP function callAnna-Maria Gleixner2016-05-031-3/+6
| | | | | | | | | | | | | | | | Since commit 3b9d6da67e11 ("cpu/hotplug: Fix rollback during error-out in __cpu_disable()") it is ensured that callbacks of CPU_ONLINE and CPU_DOWN_PREPARE are processed on the hotplugged CPU. Due to this SMP function calls are no longer required. Replace smp_call_function_single() with a direct call of setup_pmc_cpu(). To keep the calling convention, interrupts are explicitly disabled around the call. Cc: linux-s390@vger.kernel.org Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de> Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/cpum_sf: Fix cpu hotplug notifier transitionsAnna-Maria Gleixner2016-03-171-1/+1
| | | | | | | | | | | | | | | | The cpumf_pmu_notfier() hotplug callback lacks handling of the CPU_DOWN_FAILED case. That means, if CPU_DOWN_PREPARE failes, the PMC of the CPU is not setup again. Furthermore the CPU_ONLINE_FROZEN case will never be processed because of masking the switch expression with CPU_TASKS_FROZEN. Add handling for CPU_DOWN_FAILED transition to setup the PMC of the CPU. Remove CPU_ONLINE_FROZEN case. Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de> Acked-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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