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2015-04-08PCI: Fix typo in Thunderbolt kernel messageDarrick J. Wong
Fix a typo in one of the kernel messages. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2015-04-08PCI: exynos: Fix INTx enablement statement termination errorJaehoon Chung
Use a semicolon, not a comma, to terminate a statement. Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2015-04-08PCI: iproc: Add Broadcom iProc PCIe supportRay Jui
Add support for the Broadcom iProc PCIe controller. pcie-iproc.c is the common core driver, and a front-end bus interface needs to be added to support different bus interfaces. pcie-iproc-platform.c contains the support for the platform bus interface. Signed-off-by: Ray Jui <rjui@broadcom.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Scott Branden <sbranden@broadcom.com> Acked-by: Arnd Bergmann <arnd@arndb.de>
2015-04-08PCI: iproc: Add DT docs for Broadcom iProc PCIe driverRay Jui
Document the Broadcom iProc PCIe platform interface device tree binding. Signed-off-by: Ray Jui <rjui@broadcom.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Scott Branden <sbranden@broadcom.com> Acked-by: Arnd Bergmann <arnd@arndb.de>
2015-04-08PCI: Export symbols required for loadable host driver modulesRay Jui
Export the following symbols so they can be referenced by a PCI host bridge driver compiled as a kernel loadable module: pci_common_swizzle pci_create_root_bus pci_stop_root_bus pci_remove_root_bus pci_assign_unassigned_bus_resources pci_fixup_irqs Signed-off-by: Ray Jui <rjui@broadcom.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Arnd Bergmann <arnd@arndb.de>
2015-04-08ALSA: hda - Fix headphone pin config for Lifebook T731Takashi Iwai
Some BIOS version of Fujitsu Lifebook T731 seems to set up the headphone pin (0x21) without the assoc number 0x0f while it's set only to the output on the docking port (0x1a). With the recent commit [03ad6a8c93b6: ALSA: hda - Fix "PCM" name being used on one DAC when there are two DACs], this resulted in the weird mixer element mapping where the headphone on the laptop is assigned as a shared volume with the speaker and the docking port is assigned as an individual headphone. This patch improves the situation by correcting the headphone pin config to the more appropriate value. Reported-and-tested-by: Taylor Smock <smocktaylor@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2015-04-08hwmon: (ibmpowernv) pretty print labelsCédric Le Goater
The new OPAL device tree adds a few properties which can be used to add extra information on the sensor label. In the case of a cpu core sensor, the firmware exposes the physical identifier of the core in the "ibm,pir" property. The driver translates this identifier in a linux cpu number and prints out a range corresponding to the hardware threads of the core (as they share the same sensor). The numbering gives a hint on the localization of the core in the system (which socket, which chip). Signed-off-by: Cédric Le Goater <clg@fr.ibm.com> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2015-04-08hwmon: (ibmpowernv) add a label attributeCédric Le Goater
Currently, sensors are only identified by their type and index. The new OPAL device tree can expose extra properties to identify some sensors by their name or location. This patch adds the creation of a new hwmon *_label attribute when such properties are detected. Signed-off-by: Cédric Le Goater <clg@fr.ibm.com> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2015-04-08hwmon: (ibmpowernv) add support for the new device treeCédric Le Goater
The new OPAL device tree for sensors has a different layout and uses new property names, for the type and for the handler used to capture the sensor data. This patch modifies the ibmpowernv driver to support such a tree in a way preserving compatibility with older OPAL firmwares. This is achieved by changing the error path of the routine parsing an OPAL node name. The node is simply considered being from the new device tree layout and fallback values are used. Signed-off-by: Cédric Le Goater <clg@fr.ibm.com> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2015-04-08hwmon: (ibmpowernv) add a helper routine create_hwmon_attrCédric Le Goater
This should shorten a bit the code necessary to create a hmwon attribute. Signed-off-by: Cédric Le Goater <clg@fr.ibm.com> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2015-04-08Defer processing of REQ_PREEMPT requests for blocked devicesBart Van Assche
SCSI transport drivers and SCSI LLDs block a SCSI device if the transport layer is not operational. This means that in this state no requests should be processed, even if the REQ_PREEMPT flag has been set. This patch avoids that a rescan shortly after a cable pull sporadically triggers the following kernel oops: BUG: unable to handle kernel paging request at ffffc9001a6bc084 IP: [<ffffffffa04e08f2>] mlx4_ib_post_send+0xd2/0xb30 [mlx4_ib] Process rescan-scsi-bus (pid: 9241, threadinfo ffff88053484a000, task ffff880534aae100) Call Trace: [<ffffffffa0718135>] srp_post_send+0x65/0x70 [ib_srp] [<ffffffffa071b9df>] srp_queuecommand+0x1cf/0x3e0 [ib_srp] [<ffffffffa0001ff1>] scsi_dispatch_cmd+0x101/0x280 [scsi_mod] [<ffffffffa0009ad1>] scsi_request_fn+0x411/0x4d0 [scsi_mod] [<ffffffff81223b37>] __blk_run_queue+0x27/0x30 [<ffffffff8122a8d2>] blk_execute_rq_nowait+0x82/0x110 [<ffffffff8122a9c2>] blk_execute_rq+0x62/0xf0 [<ffffffffa000b0e8>] scsi_execute+0xe8/0x190 [scsi_mod] [<ffffffffa000b2f3>] scsi_execute_req+0xa3/0x130 [scsi_mod] [<ffffffffa000c1aa>] scsi_probe_lun+0x17a/0x450 [scsi_mod] [<ffffffffa000ce86>] scsi_probe_and_add_lun+0x156/0x480 [scsi_mod] [<ffffffffa000dc2f>] __scsi_scan_target+0xdf/0x1f0 [scsi_mod] [<ffffffffa000dfa3>] scsi_scan_host_selected+0x183/0x1c0 [scsi_mod] [<ffffffffa000edfb>] scsi_scan+0xdb/0xe0 [scsi_mod] [<ffffffffa000ee13>] store_scan+0x13/0x20 [scsi_mod] [<ffffffff811c8d9b>] sysfs_write_file+0xcb/0x160 [<ffffffff811589de>] vfs_write+0xce/0x140 [<ffffffff81158b53>] sys_write+0x53/0xa0 [<ffffffff81464592>] system_call_fastpath+0x16/0x1b [<00007f611c9d9300>] 0x7f611c9d92ff Reported-by: Max Gurtuvoy <maxg@mellanox.com> Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com> Reviewed-by: Mike Christie <michaelc@cs.wisc.edu> Cc: <stable@vger.kernel.org> Signed-off-by: James Bottomley <JBottomley@Odin.com>
2015-04-08be2iscsi: Fix kernel panic when device initialization failsJohn Soni Jose
Kernel panic was happening as iscsi_host_remove() was called on a host which was not yet added. Signed-off-by: John Soni Jose <sony.john-n@emulex.com> Reviewed-by: Mike Christie <michaelc@cs.wisc.edu> Cc: <stable@vger.kernel.org> Signed-off-by: James Bottomley <JBottomley@Odin.com>
2015-04-08ALSA: bebob: fix to processing in big-endian machine for sending cueTakashi Sakamoto
Some M-Audio devices require to receive bootup command just after powering on, while codes in BeBoB driver doesn't work properly in big-endian machine because the command should be aligned by little-endian. This commit fixes this bug. This fix should go to stable kernel. Cc: Takayuki Shiroma <t.shiroma.oki@gmail.com> Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Cc: <stable@vger.kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2015-04-08Revert "sparc/PCI: Clip bridge windows to fit in upstream windows"Bjorn Helgaas
This reverts commit d63e2e1f3df904bf6bd150bdafb42ddbb3257ea8. David Ahern reported that d63e2e1f3df9 breaks booting on an 8-socket T5 sparc system. He also verified that the system boots with d63e2e1f3df9 reverted. Yinghai has some fixes, but they need a little more polishing than we can do before v4.0. Link: http://lkml.kernel.org/r/5514391F.2030300@oracle.com # report Link: http://lkml.kernel.org/r/1427857069-6789-1-git-send-email-yinghai@kernel.org # patches Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> CC: stable@vger.kernel.org # v3.19+
2015-04-08Merge tag 'perf-core-for-mingo' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo: User visible changes: - Teach 'perf record' about perf_event_attr.clockid (Peter Zijlstra) - Improve 'perf sched replay' on high CPU core count machines (Yunlong Song) - Consider PERF_RECORD_ events with cpumode == 0 in 'perf top', removing one cause of long term memory usage buildup, i.e. not processing PERF_RECORD_EXIT events (Arnaldo Carvalho de Melo) - Add 'I' event modifier for perf_event_attr.exclude_idle bit (Jiri Olsa) - Respect -i option 'in perf kmem' (Jiri Olsa) Infrastructure changes: - Honor operator priority in libtraceevent (Namhyung Kim) - Merge all perf_event_attr print functions (Peter Zijlstra) - Check kmaps access to make code more robust (Wang Nan) - Fix inverted logic in perf_mmap__empty() (He Kuang) - Fix ARM 32 'perf probe' building error (Wang Nan) - Fix perf_event_attr tests (Jiri Olsa) Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-08pinctrl: Add support for PM8916 GPIO's and MPP'sIvan T. Ivanov
Add compatible string definitions and supported pin functions. Signed-off-by: Ivan T. Ivanov <ivan.ivanov@linaro.org> Acked-by: Bjorn Andersson <bjorn.andersson@sonymobile.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-04-08PCI: Don't look for ACPI hotplug parameters if ACPI is disabledBjorn Helgaas
Booting a v3.18 or newer Xen domU kernel with PCI devices passed through results in an oops (this is a 32-bit 3.13.11 dom0 with a 64-bit 4.4.0 hypervisor and 32-bit domU): BUG: unable to handle kernel paging request at 0030303e IP: [<c06ed0e6>] acpi_ns_validate_handle+0x12/0x1a Call Trace: [<c06eda4d>] ? acpi_evaluate_object+0x31/0x1fc [<c06b78e1>] ? pci_get_hp_params+0x111/0x4e0 [<c0407bc7>] ? xen_force_evtchn_callback+0x17/0x30 [<c04085fb>] ? xen_restore_fl_direct_reloc+0x4/0x4 [<c0699d34>] ? pci_device_add+0x24/0x450 Don't look for ACPI configuration information if ACPI has been disabled. I don't think this is the best fix, because we can boot plain Linux (no Xen) with "acpi=off", and we don't need this check in pci_get_hp_params(). There should be a better fix that would make Xen domU work the same way. The domU kernel has ACPI support but it has no AML. There should be a way to initialize the ACPI data structures so things fail gracefully rather than oopsing. This is an interim fix to address the regression. Fixes: 6cd33649fa83 ("PCI: Add pci_configure_device() during enumeration") Link: https://bugzilla.kernel.org/show_bug.cgi?id=96301 Reported-by: Michael D Labriola <mlabriol@gdeb.com> Tested-by: Michael D Labriola <mlabriol@gdeb.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> CC: stable@vger.kernel.org # v3.18+
2015-04-08tracing: Add enum_map file to show enums that have been mappedSteven Rostedt (Red Hat)
Add a enum_map file in the tracing directory to see what enums have been saved to convert in the print fmt files. As this requires the enum mapping to be persistent in memory, it is only created if the new config option CONFIG_TRACE_ENUM_MAP_FILE is enabled. This is for debugging and will increase the persistent memory footprint of the kernel. Link: http://lkml.kernel.org/r/20150403013802.220157513@goodmis.org Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-04-08writeback: Export enums used by tracepoint to user spaceSteven Rostedt (Red Hat)
The enums used in tracepoints for __print_symbolic() do not have their values shown in the tracepoint format files and this makes it difficult for user space tools to convert the binary values to the strings they are to represent. Add TRACE_DEFINE_ENUM(x) macros to export the enum names to their values to make the tracing output from user space tools more robust. Link: http://lkml.kernel.org/r/20150403013802.220157513@goodmis.org Cc: Dave Chinner <dchinner@redhat.com> Cc: Jens Axboe <axboe@kernel.dk> Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-04-08v4l: Export enums used by tracepoints to user spaceSteven Rostedt (Red Hat)
Enums used by tracepoints for __print_symbolic() are shown in the tracepoint format files with just their names and not their values. This makes it difficult for user space tools to know how to convert the binary data into their string representations. By adding the use of TRACE_DEFINE_ENUM(), the enum names will be mapped to their values and shown in the tracing file system to let tools convert the data as necessary. Link: http://lkml.kernel.org/r/20150403013802.220157513@goodmis.org Acked-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-04-08ata: remove deprecated use of pci apiQuentin Lambert
Replace occurences of the pci api by appropriate call to the dma api. A simplified version of the semantic patch that finds this problem is as follows: (http://coccinelle.lip6.fr) @deprecated@ idexpression id; position p; @@ ( pci_dma_supported@p ( id, ...) | pci_alloc_consistent@p ( id, ...) ) @bad1@ idexpression id; position deprecated.p; @@ ...when != &id->dev when != pci_get_drvdata ( id ) when != pci_enable_device ( id ) ( pci_dma_supported@p ( id, ...) | pci_alloc_consistent@p ( id, ...) ) @depends on !bad1@ idexpression id; expression direction; position deprecated.p; @@ ( - pci_dma_supported@p ( id, + dma_supported ( &id->dev, ... + , GFP_ATOMIC ) | - pci_alloc_consistent@p ( id, + dma_alloc_coherent ( &id->dev, ... + , GFP_ATOMIC ) ) Signed-off-by: Quentin Lambert <lambert.quentin@gmail.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2015-04-08pinctrl: bcm2835: Fix support for threaded level triggered IRQsCharles Keepax
Currently, the driver uses handle_simple_irq for all IRQ types and hard codes the acknowledge for different IRQ types into the handler. It is better to use the IRQ core as intended and let it handle the differences between the various types of IRQ. For example the current system does not work for threaded level triggered IRQs as these need to be masked until the threaded handler has run. Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-04-08gfs2: fix quota refresh race in do_glock()Abhi Das
quotad periodically syncs in-memory quotas to the ondisk quota file and sets the QDF_REFRESH flag so that a subsequent read of a synced quota is re-read from disk. gfs2_quota_lock() checks for this flag and sets a 'force' bit to force re-read from disk if requested. However, there is a race condition here. It is possible for gfs2_quota_lock() to find the QDF_REFRESH flag unset (i.e force=0) and quotad comes in immediately after and syncs the relevant quota and sets the QDF_REFRESH flag. gfs2_quota_lock() resumes with force=0 and uses the stale in-memory quota usage values that result in miscalculations. This patch fixes this race by moving the check for the QDF_REFRESH flag check further out into the gfs2_quota_lock() process, i.e, in do_glock(), under the protection of the quota glock. Signed-off-by: Abhi Das <adas@redhat.com> Signed-off-by: Bob Peterson <rpeterso@redhat.com> Acked-by: Steven Whitehouse <swhiteho@redhat.com>
2015-04-08vfio-pci: Fix use after freeAlex Williamson
Reported by 0-day test infrastructure. Fixes: ecaa1f6a0154 ("vfio-pci: Add VGA arbiter client") Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-04-08perf tools: Add 'I' event modifier for exclude_idle bitJiri Olsa
Adding 'I' event modifier to have complete set of modifiers for perf_event_attr:exclude_* bits. Any event specified with 'I' modifier will have the perf_event_attr:exclude_idle bit set. $ perf record -e cycles:I -vv ls 2>&1 | grep exclude_idle exclude_hv 0 exclude_idle 1 Adding automated tests. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Andi Kleen <andi@firstfloor.org> Cc: David Ahern <dsahern@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: William Cohen <wcohen@redhat.com> Link: http://lkml.kernel.org/r/1428441919-23099-2-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-04-08perf report: Don't call map__kmap if map is NULL.Wang Nan
report__warn_kptr_restrict() calls map__kmap(kernel_map) before checking kernel_map againest NULL. Which is dangerous, since map__kmap() will return a invalid and not NULL address. It will trigger a warning message in map__kmap() after the patch "perf: kmaps: enforce usage of kmaps to protect futher bugs." was applied. This patch fixes it by adding the missing checking. Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1428490772-135393-1-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-04-08perf tests: Fix attr testsJiri Olsa
Following commit: 1a5941312414 perf: Add wakeup watermark control to the AUX area enlarged perf_event_attr, but did not updated attr tests. Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Kaixu Xia <kaixu.xia@linaro.org> Cc: Kan Liang <kan.liang@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Robert Richter <rric@kernel.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Markus T Metzger <markus.t.metzger@intel.com> Cc: Mathieu Poirier <mathieu.poirier@linaro.org> Link: http://lkml.kernel.org/n/20150407171715.GA22603@krava.redhat.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-04-08perf probe: Fix ARM 32 building errorWang Nan
Commit 9b118acae310f57baee770b5db402500d8695e50 ("perf probe: Fix to handle aliased symbols in glibc") uses an absolute format '%lx' to print u64 argument, which causes compiling error on ARM 32. This patch replaces it with PRIx64. Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1428459274-138470-1-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-04-08SUNRPC: Export enums in tracepoints to user spaceSteven Rostedt (Red Hat)
The enums used in the tracepoints for __print_symbolic() have their names shown in the tracepoint format files. User space tools do not know how to convert those names into their values to be able to convert the binary data. Use TRACE_DEFINE_ENUM() to export the enum names to their values for userspace to do the parsing correctly. Link: http://lkml.kernel.org/r/20150403013802.220157513@goodmis.org Acked-by: Trond Myklebust <trond.myklebust@primarydata.com> Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-04-08mm: tracing: Export enums in tracepoints to user spaceSteven Rostedt (Red Hat)
The enums used in tracepoints with __print_symbolic() have their names shown in the tracepoint format files and not their values. This makes it difficult for user space tools to convert the binary data to the strings as user space does not know what those enums are about. By having them use TRACE_DEFINE_ENUM(), the names of the enums will be mapped to the values and shown to user space. Link: http://lkml.kernel.org/r/20150403013802.220157513@goodmis.org Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-04-08irq/tracing: Export enums in tracepoints to user spaceSteven Rostedt (Red Hat)
The enums used by the softirq mapping is what is shown in the output of the __print_symbolic() and not their values, that are needed to map them to their strings. Export them to userspace with the TRACE_DEFINE_ENUM() macro so that user space tools can map the enums with their values. Link: http://lkml.kernel.org/r/20150403013802.220157513@goodmis.org Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-04-08f2fs: Export the enums in the tracepoints to userspaceSteven Rostedt (Red Hat)
The tracepoints that use __print_symbolic() use enums as the value to convert to strings. Unfortunately, the format files for these tracepoints show the enum name and not their value. This causes some userspace tools not to know how to convert __print_symbolic() to their strings. Add TRACE_DEFINE_ENUM() macros to export the enums used to userspace to let those tools know what those enum values are. Link: http://lkml.kernel.org/r/20150403013802.220157513@goodmis.org Cc: Namjae Jeon <namjae.jeon@samsung.com> Cc: Pankaj Kumar <pankaj.km@samsung.com> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-04-08net/9p/tracing: Export enums in tracepoints to userspaceSteven Rostedt (Red Hat)
The tracepoints in the 9p code use a lot of enums for the __print_symbolic() function. These enums are shown in the tracepoint format files, and user space tools such as trace-cmd does not have the information to parse it. Add helper macros to export the enums with TRACE_DEFINE_ENUM(). Link: http://lkml.kernel.org/r/20150403013802.220157513@goodmis.org Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: Eric Van Hensbergen <ericvh@gmail.com> Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-04-08x86/tlb/trace: Export enums in used by tlb_flush tracepointSteven Rostedt (Red Hat)
Have the enums used in __print_symbolic() by the trace_tlb_flush() tracepoint exported to userpace such that they can be parsed by userspace tools. Link: http://lkml.kernel.org/r/20150403013802.220157513@goodmis.org Cc: Dave Hansen <dave@sr71.net> Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-04-08tracing/samples: Update the trace-event-sample.h with TRACE_DEFINE_ENUM()Steven Rostedt (Red Hat)
Document the use of TRACE_DEFINE_ENUM() by adding enums to the trace-event-sample.h and using this macro to convert them in the format files. Also update the comments and sho the use of __print_symbolic() and __print_flags() as well as adding comments abount __print_array(). Link: http://lkml.kernel.org/r/20150403013802.220157513@goodmis.org Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-04-08tracing: Allow for modules to convert their enums to valuesSteven Rostedt (Red Hat)
Update the infrastructure such that modules that declare TRACE_DEFINE_ENUM() will have those enums converted into their values in the tracepoint print fmt strings. Link: http://lkml.kernel.org/r/87vbhjp74q.fsf@rustcorp.com.au Acked-by: Rusty Russell <rusty@rustcorp.com.au> Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-04-08tracing: Add TRACE_DEFINE_ENUM() macro to map enums to their valuesSteven Rostedt (Red Hat)
Several tracepoints use the helper functions __print_symbolic() or __print_flags() and pass in enums that do the mapping between the binary data stored and the value to print. This works well for reading the ASCII trace files, but when the data is read via userspace tools such as perf and trace-cmd, the conversion of the binary value to a human string format is lost if an enum is used, as userspace does not have access to what the ENUM is. For example, the tracepoint trace_tlb_flush() has: __print_symbolic(REC->reason, { TLB_FLUSH_ON_TASK_SWITCH, "flush on task switch" }, { TLB_REMOTE_SHOOTDOWN, "remote shootdown" }, { TLB_LOCAL_SHOOTDOWN, "local shootdown" }, { TLB_LOCAL_MM_SHOOTDOWN, "local mm shootdown" }) Which maps the enum values to the strings they represent. But perf and trace-cmd do no know what value TLB_LOCAL_MM_SHOOTDOWN is, and would not be able to map it. With TRACE_DEFINE_ENUM(), developers can place these in the event header files and ftrace will convert the enums to their values: By adding: TRACE_DEFINE_ENUM(TLB_FLUSH_ON_TASK_SWITCH); TRACE_DEFINE_ENUM(TLB_REMOTE_SHOOTDOWN); TRACE_DEFINE_ENUM(TLB_LOCAL_SHOOTDOWN); TRACE_DEFINE_ENUM(TLB_LOCAL_MM_SHOOTDOWN); $ cat /sys/kernel/debug/tracing/events/tlb/tlb_flush/format [...] __print_symbolic(REC->reason, { 0, "flush on task switch" }, { 1, "remote shootdown" }, { 2, "local shootdown" }, { 3, "local mm shootdown" }) The above is what userspace expects to see, and tools do not need to be modified to parse them. Link: http://lkml.kernel.org/r/20150403013802.220157513@goodmis.org Cc: Guilherme Cox <cox@computer.org> Cc: Tony Luck <tony.luck@gmail.com> Cc: Xie XiuQi <xiexiuqi@huawei.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-04-08tracing: Update trace-event-sample with TRACE_SYSTEM_VAR documentationSteven Rostedt (Red Hat)
Add documentation about TRACE_SYSTEM needing to be alpha-numeric or with underscores, and that if it is not, then the use of TRACE_SYSTEM_VAR is required to make something that is. An example of this is shown in samples/trace_events/trace-events-sample.h Link: http://lkml.kernel.org/r/20150403013802.220157513@goodmis.org Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-04-08tracing: Give system name a pointerSteven Rostedt (Red Hat)
Normally the compiler will use the same pointer for a string throughout the file. But there's no guarantee of that happening. Later changes will require that all events have the same pointer to the system string. Name the system string and have all events point to it. Testing this, it did not increases the size of the text, except for the notes section, which should not harm the real size any. Link: http://lkml.kernel.org/r/20150403013802.220157513@goodmis.org Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-04-08brcmsmac: Move each system tracepoints to their own headerSteven Rostedt (Red Hat)
Every tracing file must have its own TRACE_SYSTEM defined. The brcmsmac tracepoint header broke this and added in the middle of the file: #undef TRACE_SYSTEM #define TRACE_SYSTEM brcmsmac #undef TRACE_SYSTEM #define TRACE_SYSTEM brcmsmac_tx #undef TRACE_SYSTEM #define TRACE_SYSTEM brcmsmac_msg Unfortunately, this broke new code in the ftrace infrastructure. Moving each of these TRACE_SYSTEMs into their own trace file with just one TRACE_SYSTEM per file fixes the issue. Link: http://lkml.kernel.org/r/5524D99C.1050902@broadcom.com Acked-by: Arend van Spriel <arend@broadcom.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-04-08iwlwifi: Move each system tracepoints to their own headerSteven Rostedt (Red Hat)
Every tracing file must have its own TRACE_SYSTEM defined. The iwlwifi tracepoint header broke this and added in the middle of the file: #undef TRACE_SYSTEM #define TRACE_SYSTEM iwlwifi_io #undef TRACE_SYSTEM #define TRACE_SYSTEM iwlwifi_ucode #undef TRACE_SYSTEM #define TRACE_SYSTEM iwlwifi_msg #undef TRACE_SYSTEM #define TRACE_SYSTEM iwlwifi_data #undef TRACE_SYSTEM #define TRACE_SYSTEM iwlwifi Unfortunately, this broke new code in the ftrace infrastructure. Moving each of these TRACE_SYSTEMs into their own trace file with just one TRACE_SYSTEM per file fixes the issue. Link: http://lkml.kernel.org/r/1428479094.2809.3.camel@sipsolutions.net Reviewed-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-04-08perf tools: Merge all perf_event_attr print functionsPeter Zijlstra
Currently there's 3 (that I found) different and incomplete implementations of printing perf_event_attr. This is quite silly. Merge the lot. While this patch does not retain the exact form all printing that I found is debug output and thus it should not be critical. Also, I cannot find a single print_event_desc() caller. Pre: $ perf record -vv -e cycles -- sleep 1 ------------------------------------------------------------ perf_event_attr: type 0 size 104 config 0 sample_period 4000 sample_freq 4000 sample_type 0x107 read_format 0 disabled 1 inherit 1 pinned 0 exclusive 0 exclude_user 0 exclude_kernel 0 exclude_hv 0 exclude_idle 0 mmap 1 comm 1 mmap2 1 comm_exec 1 freq 1 inherit_stat 0 enable_on_exec 1 task 1 watermark 0 precise_ip 0 mmap_data 0 sample_id_all 1 exclude_host 0 exclude_guest 1 excl.callchain_kern 0 excl.callchain_user 0 wakeup_events 0 wakeup_watermark 0 bp_type 0 bp_addr 0 config1 0 bp_len 0 config2 0 branch_sample_type 0 sample_regs_user 0 sample_stack_user 0 sample_regs_intr 0 ------------------------------------------------------------ $ perf evlist -vv cycles: sample_freq=4000, size: 104, sample_type: IP|TID|TIME|PERIOD, disabled: 1, inherit: 1, mmap: 1, mmap2: 1, comm: 1, comm_exec: 1, freq: 1, enable_on_exec: 1, task: 1, sample_id_all: 1, exclude_guest: 1 Post: $ ./perf record -vv -e cycles -- sleep 1 ------------------------------------------------------------ perf_event_attr: size 112 { sample_period, sample_freq } 4000 sample_type IP|TID|TIME|PERIOD disabled 1 inherit 1 mmap 1 comm 1 freq 1 enable_on_exec 1 task 1 sample_id_all 1 exclude_guest 1 mmap2 1 comm_exec 1 ------------------------------------------------------------ $ ./perf evlist -vv cycles: size: 112, { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|PERIOD, disabled: 1, inherit: 1, mmap: 1, comm: 1, freq: 1, enable_on_exec: 1, task: 1, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1 Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Adrian Hunter <adrian.hunter@intel.com> Acked-by: Ingo Molnar <mingo@kernel.org> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: David Ahern <dsahern@gmail.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20150407091150.644238729@infradead.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-04-08perf record: Add clockid parameterPeter Zijlstra
Teach perf-record about the new perf_event_attr::{use_clockid, clockid} fields. Add a simple parameter to set the clock (if any) to be used for the events to be recorded into the data file. Since we store the entire perf_event_attr in the EVENT_DESC section we also already store the used clockid in the data file. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: David Ahern <dsahern@gmail.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Yunlong Song <yunlong.song@huawei.com> Link: http://lkml.kernel.org/r/20150407154851.GR23123@twins.programming.kicks-ass.net [ Conditionally define CLOCK_BOOTTIME, at least rhel6 doesn't have it - dsahern Ditto for CLOCK_MONOTONIC_RAW, sles11sp2 doesn't have it - yunlong.song ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-04-08perf sched replay: Use replay_repeat to calculate the runavg of cpu usage ↵Yunlong Song
instead of the default value 10 Since sched->replay_repeat is set to 10 as default, the sched->run_avg, sched->runavg_cpu_usage, and sched->runavg_parent_cpu_usage all use 10 to calculate their value. However, the replay_repeat can be changed to other value by using -r option, so the calculation above should use replay_repeat to achieve more accurate results instead of the default value 10. Signed-off-by: Yunlong Song <yunlong.song@huawei.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/r/1427809596-29559-10-git-send-email-yunlong.song@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-04-08perf sched replay: Support using -f to override perf.data file ownershipYunlong Song
Enable to use perf.data when it is not owned by current user or root. Example: $ ls -al perf.data -rw------- 1 Yunlong.Song Yunlong.Song 5321918 Mar 25 15:14 perf.data $ sudo id uid=0(root) gid=0(root) groups=0(root),64(pkcs11) Before this patch: $ sudo perf sched replay -f run measurement overhead: 98 nsecs sleep measurement overhead: 52909 nsecs the run test took 1000015 nsecs the sleep test took 1054253 nsecs File perf.data not owned by current user or root (use -f to override) As shown above, the -f option does not work at all. After this patch: $ sudo perf sched replay -f run measurement overhead: 221 nsecs sleep measurement overhead: 40514 nsecs the run test took 1000003 nsecs the sleep test took 1056098 nsecs nr_run_events: 10 nr_sleep_events: 1562 nr_wakeup_events: 5 task 0 ( :1: 1), nr_events: 1 task 1 ( :2: 2), nr_events: 1 task 2 ( :3: 3), nr_events: 1 ... ... task 1549 ( :163132: 163132), nr_events: 1 task 1550 ( :163540: 163540), nr_events: 1 task 1551 ( <unknown>: 0), nr_events: 10 ------------------------------------------------------------ #1 : 50.198, ravg: 50.20, cpu: 2335.18 / 2335.18 #2 : 219.099, ravg: 67.09, cpu: 2835.11 / 2385.17 #3 : 238.626, ravg: 84.24, cpu: 3278.26 / 2474.48 #4 : 200.364, ravg: 95.85, cpu: 2977.41 / 2524.77 #5 : 176.882, ravg: 103.96, cpu: 2801.35 / 2552.43 #6 : 191.093, ravg: 112.67, cpu: 2813.70 / 2578.56 #7 : 189.448, ravg: 120.35, cpu: 2809.21 / 2601.62 #8 : 200.637, ravg: 128.38, cpu: 2849.91 / 2626.45 #9 : 248.338, ravg: 140.37, cpu: 4380.61 / 2801.87 #10 : 511.139, ravg: 177.45, cpu: 3077.73 / 2829.45 As shown above, the -f option really works now. Besides for replay, -f option can also work for latency and map. Signed-off-by: Yunlong Song <yunlong.song@huawei.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/r/1427809596-29559-9-git-send-email-yunlong.song@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-04-08perf sched replay: Fix the EMFILE error caused by the limitation of the ↵Yunlong Song
maximum open files The soft maximum number of open files for a calling process is 1024, which is defined as INR_OPEN_CUR in include/uapi/linux/fs.h, and the hard maximum number of open files for a calling process is 4096, which is defined as INR_OPEN_MAX in include/uapi/linux/fs.h. Both INR_OPEN_CUR and INR_OPEN_MAX are used to limit the value of RLIMIT_NOFILE in include/asm-generic/resource.h. And the soft maximum number finally decides the limitation of the maximum files which are allowed to be opened. That is to say a process can use at most 1024 file descriptors for its o pened files, or an EMFILE error will happen. This error can be fixed by increasing the soft maximum number, under the constraint that the soft maximum number can not exceed the hard maximum number, or both soft and hard maximum number should be increased simultaneously with privilege. For perf sched replay, it uses sys_perf_event_open to create the file descriptor for each of the tasks in order to handle information of perf events. That is to say each task needs a unique file descriptor. In x86_64, there may be over 1024 or 4096 tasks correspoinding to the record in perf.data, which causes that no enough file descriptors can be used. As a result, EMFILE error happens and stops the replay process. To solve this problem, we adaptively increase the soft and hard maximum number of open files with a '-f' option. Example: Test environment: x86_64 with 160 cores $ cat /proc/sys/kernel/pid_max 163840 $ cat /proc/sys/fs/file-max 6815744 $ ulimit -Sn 1024 $ ulimit -Hn 4096 Before this patch: $ perf sched replay ... task 1549 ( :163132: 163132), nr_events: 1 task 1550 ( :163540: 163540), nr_events: 1 task 1551 ( <unknown>: 0), nr_events: 10 Error: sys_perf_event_open() syscall returned with -1 (Too many open files) After this patch: $ perf sched replay ... task 1549 ( :163132: 163132), nr_events: 1 task 1550 ( :163540: 163540), nr_events: 1 task 1551 ( <unknown>: 0), nr_events: 10 Error: sys_perf_event_open() syscall returned with -1 (Too many open files) Have a try with -f option $ perf sched replay -f ... task 1549 ( :163132: 163132), nr_events: 1 task 1550 ( :163540: 163540), nr_events: 1 task 1551 ( <unknown>: 0), nr_events: 10 ------------------------------------------------------------ #1 : 54.401, ravg: 54.40, cpu: 3285.21 / 3285.21 #2 : 199.548, ravg: 68.92, cpu: 4999.65 / 3456.66 #3 : 170.483, ravg: 79.07, cpu: 1349.94 / 3245.99 #4 : 192.034, ravg: 90.37, cpu: 1322.88 / 3053.67 #5 : 182.929, ravg: 99.62, cpu: 1406.51 / 2888.96 #6 : 152.974, ravg: 104.96, cpu: 1167.54 / 2716.82 #7 : 155.579, ravg: 110.02, cpu: 2992.53 / 2744.39 #8 : 130.557, ravg: 112.08, cpu: 1126.43 / 2582.59 #9 : 138.520, ravg: 114.72, cpu: 1253.22 / 2449.65 #10 : 134.328, ravg: 116.68, cpu: 1587.95 / 2363.48 Signed-off-by: Yunlong Song <yunlong.song@huawei.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/r/1427809596-29559-8-git-send-email-yunlong.song@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-04-08perf sched replay: Handle the dead halt of sem_wait when create_tasks() ↵Yunlong Song
fails for any task Since there is sem_wait for each task in the wait_for_tasks(), e.g. sem_wait(&task->work_done_sem). The sem_wait can continue only when work_done_sem is greater than 0, or it will be blocked. For perf sched replay, one task may sem_post the work_done_sem of another task, which causes the work_done_sem of that task processed in a reasonable sequence, e.g. sem_post, sem_wait, sem_wait, sem_post... This sequence simulates the sched process of the running tasks at the time when perf sched record runs. As a result, all the tasks are required and their threads must be successfully created. If any one (task A) of the tasks fails to create its thread, then another task (task B), whose work_done_sem needs sem_post from that failed task A, may likely block itself due to seg_wait. And this is a dead halt, since task B's thread_func cannot continue at all. To solve this problem, perf sched replay should exit once any task fails to create its thread. Example: Test environment: x86_64 with 160 cores Before this patch: $ perf sched replay ... Error: sys_perf_event_open() syscall returned with -1 (Too many open files) ------------------------------------------------------------ <- dead halt After this patch: $ perf sched replay ... task 1551 ( <unknown>: 0), nr_events: 10 Error: sys_perf_event_open() syscall returned with -1 (Too many open files) $ As shown above, perf sched replay finishes the process after printing an error message and does not block itself. Signed-off-by: Yunlong Song <yunlong.song@huawei.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/r/1427809596-29559-7-git-send-email-yunlong.song@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-04-08perf sched replay: Fix the segmentation fault problem caused by pr_err in ↵Yunlong Song
threads The pr_err in self_open_counters() prints error message to stderr. Unlike stdout, stderr uses memory buffer on the stack of each calling process. The pr_err in self_open_counters() works in a thread called thread_func created in function create_tasks, which concurrently creates sched->nr_tasks threads. If the error happens and pr_err prints the error message in each of these threads, the stack size of the perf process (default is 8192 kbytes) will quickly run out and the segmentation fault will happen then. To solve this problem, pr_err with self_open_counters() should be moved from newly created threads to the old main thread of the perf process. Then the pr_err can work in a stable situation without the strange segmentation fault problem. Example: Test environment: x86_64 with 160 cores Before this patch: $ perf sched replay ... task 1549 ( :163132: 163132), nr_events: 1 task 1550 ( :163540: 163540), nr_events: 1 task 1551 ( <unknown>: 0), nr_events: 10 Segmentation fault After this patch: $ perf sched replay ... task 1549 ( :163132: 163132), nr_events: 1 task 1550 ( :163540: 163540), nr_events: 1 task 1551 ( <unknown>: 0), nr_events: 10 ... As shown above, the result continues without any segmentation fault. Signed-off-by: Yunlong Song <yunlong.song@huawei.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/r/1427809596-29559-6-git-send-email-yunlong.song@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-04-08perf sched replay: Realloc the memory of pid_to_task stepwise to adapt to ↵Yunlong Song
the different pid_max configurations Although the memory of pid_to_task can be allocated via calloc according to the value of /proc/sys/kernel/pid_max, it cannot handle the case when pid_max is changed after 'perf sched record' has created its perf.data. If the new pid_max configured in 'perf sched replay' is smaller than the old pid_max configured in 'perf sched record', then it will cause the assertion failure problem. To solve this problem, we realloc the memory of pid_to_task stepwise once the passed-in pid parameter in register_pid is larger than the current pid_max. Example: Test environment: x86_64 with 160 cores $ cat /proc/sys/kernel/pid_max 163840 $ perf sched record ls $ echo 5000 > /proc/sys/kernel/pid_max $ cat /proc/sys/kernel/pid_max 5000 Before this patch: $ perf sched replay run measurement overhead: 221 nsecs sleep measurement overhead: 55356 nsecs the run test took 1000011 nsecs the sleep test took 1060940 nsecs perf: builtin-sched.c:337: register_pid: Assertion `!(pid >= (unsigned long)pid_max)' failed. Aborted After this patch: $ perf sched replay run measurement overhead: 221 nsecs sleep measurement overhead: 55611 nsecs the run test took 1000026 nsecs the sleep test took 1060486 nsecs nr_run_events: 10 nr_sleep_events: 1562 nr_wakeup_events: 5 task 0 ( :1: 1), nr_events: 1 task 1 ( :2: 2), nr_events: 1 task 2 ( :3: 3), nr_events: 1 task 3 ( :5: 5), nr_events: 1 ... Signed-off-by: Yunlong Song <yunlong.song@huawei.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/r/1427809596-29559-5-git-send-email-yunlong.song@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-04-08perf sched replay: Alloc the memory of pid_to_task dynamically to adapt to ↵Yunlong Song
the unexpected change of pid_max The current memory allocation of struct task_desc *pid_to_task[MAX_PID] is in a permanent and preset way, and it has two problems: Problem 1: If the pid_max, which is the max number of pids in the system, is much smaller than MAX_PID (1024*1000), then it causes a waste of stack memory. This may happen in the case where the number of cpu cores is much smaller than 1000. Problem 2: If the pid_max is changed from the default value to a value larger than MAX_PID, then it will cause assertion failure problem. The maximum value of pid_max can be set to pid_max_max (see pidmap_init defined in kernel/pid.c), which equals to PID_MAX_LIMIT. In x86_64, PID_MAX_LIMIT is 4*1024*1024 (defined in include/linux/threads.h). This value is much larger than MAX_PID, and will take up 32768 Kbytes (4*1024*1024*8/1024) for memory allocation of pid_to_task, which is much larger than the default 8192 Kbytes of the stack size of calling process. Due to these two problems, we use calloc to allocate the memory of pid_to_task dynamically. Example: Test environment: x86_64 with 160 cores $ cat /proc/sys/kernel/pid_max 163840 $ echo 1025000 > /proc/sys/kernel/pid_max $ cat /proc/sys/kernel/pid_max 1025000 Run some applications until the pid of some process is greater than the value of MAX_PID (1024*1000). Before this patch: $ perf sched replay run measurement overhead: 221 nsecs sleep measurement overhead: 55480 nsecs the run test took 1000008 nsecs the sleep test took 1063151 nsecs perf: builtin-sched.c:330: register_pid: Assertion `!(pid >= 1024000)' failed. Aborted After this patch: $ perf sched replay run measurement overhead: 221 nsecs sleep measurement overhead: 55435 nsecs the run test took 1000004 nsecs the sleep test took 1059312 nsecs nr_run_events: 10 nr_sleep_events: 1562 nr_wakeup_events: 5 task 0 ( :1: 1), nr_events: 1 task 1 ( :2: 2), nr_events: 1 task 2 ( :3: 3), nr_events: 1 task 3 ( :5: 5), nr_events: 1 ... Signed-off-by: Yunlong Song <yunlong.song@huawei.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/r/1427809596-29559-4-git-send-email-yunlong.song@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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