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2012-10-07Merge branch 'virtio-next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux Pull virtio changes from Rusty Russell: "New workflow: same git trees pulled by linux-next get sent straight to Linus. Git is awkward at shuffling patches compared with quilt or mq, but that doesn't happen often once things get into my -next branch." * 'virtio-next' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (24 commits) lguest: fix occasional crash in example launcher. virtio-blk: Disable callback in virtblk_done() virtio_mmio: Don't attempt to create empty virtqueues virtio_mmio: fix off by one error allocating queue drivers/virtio/virtio_pci.c: fix error return code virtio: don't crash when device is buggy virtio: remove CONFIG_VIRTIO_RING virtio: add help to CONFIG_VIRTIO option. virtio: support reserved vqs virtio: introduce an API to set affinity for a virtqueue virtio-ring: move queue_index to vring_virtqueue virtio_balloon: not EXPERIMENTAL any more. virtio-balloon: dependency fix virtio-blk: fix NULL checking in virtblk_alloc_req() virtio-blk: Add REQ_FLUSH and REQ_FUA support to bio path virtio-blk: Add bio-based IO path for virtio-blk virtio: console: fix error handling in init() function tools: Fix pthread flag for Makefile of trace-agent used by virtio-trace tools: Add guest trace agent as a user tool virtio/console: Allocate scatterlist according to the current pipe size ...
2012-10-07Merge tag 'for-v3.7' of git://git.infradead.org/users/cbou/linux-pstoreLinus Torvalds
Pull pstore changes from Anton Vorontsov: 1) We no longer ad-hoc to the function tracer "high level" infrastructure and no longer use its debugfs knobs. The change slightly touches kernel/trace directory, but it got the needed ack from Steven Rostedt: http://lkml.org/lkml/2012/8/21/688 2) Added maintainers entry; 3) A bunch of fixes, nothing special. * tag 'for-v3.7' of git://git.infradead.org/users/cbou/linux-pstore: pstore: Avoid recursive spinlocks in the oops_in_progress case pstore/ftrace: Convert to its own enable/disable debugfs knob pstore/ram: Add missing platform_device_unregister MAINTAINERS: Add pstore maintainers pstore/ram: Mark ramoops_pstore_write_buf() as notrace pstore/ram: Fix printk format warning pstore/ram: Fix possible NULL dereference
2012-10-02Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull user namespace changes from Eric Biederman: "This is a mostly modest set of changes to enable basic user namespace support. This allows the code to code to compile with user namespaces enabled and removes the assumption there is only the initial user namespace. Everything is converted except for the most complex of the filesystems: autofs4, 9p, afs, ceph, cifs, coda, fuse, gfs2, ncpfs, nfs, ocfs2 and xfs as those patches need a bit more review. The strategy is to push kuid_t and kgid_t values are far down into subsystems and filesystems as reasonable. Leaving the make_kuid and from_kuid operations to happen at the edge of userspace, as the values come off the disk, and as the values come in from the network. Letting compile type incompatible compile errors (present when user namespaces are enabled) guide me to find the issues. The most tricky areas have been the places where we had an implicit union of uid and gid values and were storing them in an unsigned int. Those places were converted into explicit unions. I made certain to handle those places with simple trivial patches. Out of that work I discovered we have generic interfaces for storing quota by projid. I had never heard of the project identifiers before. Adding full user namespace support for project identifiers accounts for most of the code size growth in my git tree. Ultimately there will be work to relax privlige checks from "capable(FOO)" to "ns_capable(user_ns, FOO)" where it is safe allowing root in a user names to do those things that today we only forbid to non-root users because it will confuse suid root applications. While I was pushing kuid_t and kgid_t changes deep into the audit code I made a few other cleanups. I capitalized on the fact we process netlink messages in the context of the message sender. I removed usage of NETLINK_CRED, and started directly using current->tty. Some of these patches have also made it into maintainer trees, with no problems from identical code from different trees showing up in linux-next. After reading through all of this code I feel like I might be able to win a game of kernel trivial pursuit." Fix up some fairly trivial conflicts in netfilter uid/git logging code. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (107 commits) userns: Convert the ufs filesystem to use kuid/kgid where appropriate userns: Convert the udf filesystem to use kuid/kgid where appropriate userns: Convert ubifs to use kuid/kgid userns: Convert squashfs to use kuid/kgid where appropriate userns: Convert reiserfs to use kuid and kgid where appropriate userns: Convert jfs to use kuid/kgid where appropriate userns: Convert jffs2 to use kuid and kgid where appropriate userns: Convert hpfs to use kuid and kgid where appropriate userns: Convert btrfs to use kuid/kgid where appropriate userns: Convert bfs to use kuid/kgid where appropriate userns: Convert affs to use kuid/kgid wherwe appropriate userns: On alpha modify linux_to_osf_stat to use convert from kuids and kgids userns: On ia64 deal with current_uid and current_gid being kuid and kgid userns: On ppc convert current_uid from a kuid before printing. userns: Convert s390 getting uid and gid system calls to use kuid and kgid userns: Convert s390 hypfs to use kuid and kgid where appropriate userns: Convert binder ipc to use kuids userns: Teach security_path_chown to take kuids and kgids userns: Add user namespace support to IMA userns: Convert EVM to deal with kuids and kgids in it's hmac computation ...
2012-09-28ftrace: Allow stealing pages from pipe bufferMasami Hiramatsu
Use generic steal operation on pipe buffer to allow stealing ring buffer's read page from pipe buffer. Note that this could reduce the performance of splice on the splice_write side operation without affinity setting. Since the ring buffer's read pages are allocated on the tracing-node, but the splice user does not always execute splice write side operation on the same node. In this case, the page will be accessed from the another node. Thus, it is strongly recommended to assign the splicing thread to corresponding node. Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-09-24trace: Move trace event enable from fs_initcall to core_initcallEzequiel Garcia
This patch splits trace event initialization in two stages: * ftrace enable * sysfs event entry creation This allows to capture trace events from an earlier point by using 'trace_event' kernel parameter and is important to trace boot-up allocations. Note that, in order to enable events at core_initcall, it's necessary to move init_ftrace_syscalls() from core_initcall to early_initcall. Link: http://lkml.kernel.org/r/1347461277-25302-1-git-send-email-elezegarcia@gmail.com Signed-off-by: Ezequiel Garcia <elezegarcia@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-09-24tracing: Add an option for disabling markersMandeep Singh Baines
In our application, we have trace markers spread through user-space. We have markers in GL, X, etc. These are super handy for Chrome's about:tracing feature (Chrome + system + kernel trace view), but can be very distracting when you're trying to debug a kernel issue. I normally, use "grep -v tracing_mark_write" but it would be nice if I could just temporarily disable markers all together. Link: http://lkml.kernel.org/r/1347066739-26285-1-git-send-email-msb@chromium.org CC: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Mandeep Singh Baines <msb@chromium.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-09-18userns: Teach trace to use from_kuidEric W. Biederman
- When tracing capture the kuid. - When displaying the data to user space convert the kuid into the user namespace of the process that opened the report file. Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2012-09-14Merge branch 'tip/perf/core' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace into perf/core Pull tracing updates from Steve Rostedt. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-09-13trace: Stop compiling in trace_clock unconditionallyJosh Triplett
Commit 56449f437 "tracing: make the trace clocks available generally", in April 2009, made trace_clock available unconditionally, since CONFIG_X86_DS used it too. Commit faa4602e47 "x86, perf, bts, mm: Delete the never used BTS-ptrace code", in March 2010, removed CONFIG_X86_DS, and now only CONFIG_RING_BUFFER (split out from CONFIG_TRACING for general use) has a dependency on trace_clock. So, only compile in trace_clock with CONFIG_RING_BUFFER or CONFIG_TRACING enabled. Link: http://lkml.kernel.org/r/20120903024513.GA19583@leaf Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Josh Triplett <josh@joshtriplett.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-09-13tracing: Skip printing "OK" if failed to disable eventYuanhan Liu
No acutal case found. But logically, we should skip "OK" in case any error met. Link: http://lkml.kernel.org/r/1346051625-25231-1-git-send-email-yuanhan.liu@linux.intel.com Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-09-06pstore/ftrace: Convert to its own enable/disable debugfs knobAnton Vorontsov
With this patch we no longer reuse function tracer infrastructure, now we register our own tracer back-end via a debugfs knob. It's a bit more code, but that is the only downside. On the bright side we have: - Ability to make persistent_ram module removable (when needed, we can move ftrace_ops struct into a module). Note that persistent_ram is still not removable for other reasons, but with this patch it's just one thing less to worry about; - Pstore part is more isolated from the generic function tracer. We tried it already by registering our own tracer in available_tracers, but that way we're loosing ability to see the traces while we record them to pstore. This solution is somewhere in the middle: we only register "internal ftracer" back-end, but not the "front-end"; - When there is only pstore tracing enabled, the kernel will only write to the pstore buffer, omitting function tracer buffer (which, of course, still can be enabled via 'echo function > current_tracer'). Suggested-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
2012-08-28Merge branch 'perf/urgent' into perf/coreIngo Molnar
Pick up the latest fixes because upcoming uprobes changes will rely on it. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-08-23ftrace: Do not test frame pointers if -mfentry is usedSteven Rostedt
The function graph has a test to check if the frame pointer is corrupted, which can happen with various options of gcc with mcount. But this is not an issue with -mfentry as -mfentry does not need nor use frame pointers for function graph tracing. Link: http://lkml.kernel.org/r/20120807194059.773895870@goodmis.org Acked-by: H. Peter Anvin <hpa@linux.intel.com> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: Andi Kleen <andi@firstfloor.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-08-23ftrace: Add -mfentry to Makefile on function tracerSteven Rostedt
Thanks to Andi Kleen, gcc 4.6.0 now supports -mfentry for x86 (and hopefully soon for other archs). What this does is to have the function profiler start at the beginning of the function instead of after the stack is set up. As plain -pg (mcount) is called after the stack is set up, and in some cases can have issues with the function graph tracer. It also requires frame pointers to be enabled. The -mfentry now calls __fentry__ at the beginning of the function. This allows for compiling without frame pointers and even has the ability to access parameters if needed. If the architecture and the compiler both support -mfentry then use that instead. Link: http://lkml.kernel.org/r/20120807194059.392617243@goodmis.org Acked-by: H. Peter Anvin <hpa@linux.intel.com> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: Michal Marek <mmarek@suse.cz> Cc: Andi Kleen <andi@firstfloor.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-08-21Merge branch 'tip/perf/core-2' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace into perf/core Pull ftrace fixlets from Steve Rostedt. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-08-21Merge 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: * Fix include order for bison/flex-generated C files, from Ben Hutchings * Build fixes and documentation corrections from David Ahern * Group parsing support, from Jiri Olsa * UI/gtk refactorings and improvements from Namhyung Kim * NULL deref fix for perf script, from Namhyung Kim * Assorted cleanups from Robert Richter * Let O= makes handle relative paths, from Steven Rostedt * perf script python fixes, from Feng Tang. * Improve 'perf lock' error message when the needed tracepoints are not present, from David Ahern. * Initial bash completion support, from Frederic Weisbecker * Allow building without libelf, from Namhyung Kim. * Support DWARF CFI based unwind to have callchains when %bp based unwinding is not possible, from Jiri Olsa. * Symbol resolution fixes, while fixing support PPC64 files with an .opt ELF section was the end goal, several fixes for code that handles all architectures and cleanups are included, from Cody Schafer. * Add a description for the JIT interface, from Andi Kleen. * Assorted fixes for Documentation and build in 32 bit, from Robert Richter * Add support for non-tracepoint events in perf script python, from Feng Tang * Cache the libtraceevent event_format associated to each evsel early, so that we avoid relookups, i.e. calling pevent_find_event repeatedly when processing tracepoint events. [ This is to reduce the surface contact with libtraceevents and make clear what is that the perf tools needs from that lib: so far parsing the common and per event fields. ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-08-17tracing/syscalls: Fix perf syscall tracing when syscall_nr == -1Will Deacon
syscall_get_nr can return -1 in the case that the task is not executing a system call. This patch fixes perf_syscall_{enter,exit} to check that the syscall number is valid before using it as an index into a bitmap. Link: http://lkml.kernel.org/r/1345137254-7377-1-git-send-email-will.deacon@arm.com Cc: Jason Baron <jbaron@redhat.com> Cc: Wade Farnsworth <wade_farnsworth@mentor.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-08-07tracing/trivial: Fix some typos in kernel/traceWang Tianhong
Fix some typos in kernel/trace. Link: http://lkml.kernel.org/r/1343887320.2228.9.camel@louis-ThinkPad-T410 Signed-off-by: Wang Tianhong <wangthbj@linux.vnet.ibm.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-08-07tracing/filter: Add missing initializationJiri Olsa
Add missing initialization for ret variable. Its initialization is based on the re_cnt variable, which is being set deep down in the ftrace_function_filter_re function. I'm not sure compilers would be smart enough to see this in near future, so killing the warning this way. Link: http://lkml.kernel.org/r/1340120894-9465-2-git-send-email-jolsa@redhat.com Signed-off-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-08-07tracing: Fix wakeup_rt self test on virtual machinesSteven Rostedt
The warkeup_rt self test used msleep() calls to wait for real time tasks to wake up and run. On bare-metal hardware, this was enough as the scheduler should let the RT task run way before the non-RT task wakes up from the msleep(). If it did not, then that would mean the scheduler was broken. But when dealing with virtual machines, this is a different story. If the RT task wakes up on a VCPU, it's up to the host to decide when that task gets to schedule, which can be far behind the time that the non-RT task wakes up. In this case, the test would fail incorrectly. As we are not testing the scheduler, but instead the wake up tracing, we can use completions to wait and not depend on scheduler timings to see if events happen on time. Link: http://lkml.kernel.org/r/1343663105.3847.7.camel@fedora Reported-by: Fengguang Wu <fengguang.wu@intel.com> Tested-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-08-03Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Ingo Molnar: "Fix merge window fallout and fix sleep profiling (this was always broken, so it's not a fix for the merge window - we can skip this one from the head of the tree)." * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/trace: Add ability to set a target task for events perf/x86: Fix USER/KERNEL tagging of samples properly perf/x86/intel/uncore: Make UNCORE_PMU_HRTIMER_INTERVAL 64-bit
2012-07-31perf/trace: Add ability to set a target task for eventsAndrew Vagin
A few events are interesting not only for a current task. For example, sched_stat_* events are interesting for a task which wakes up. For this reason, it will be good if such events will be delivered to a target task too. Now a target task can be set by using __perf_task(). The original idea and a draft patch belongs to Peter Zijlstra. I need these events for profiling sleep times. sched_switch is used for getting callchains and sched_stat_* is used for getting time periods. These events are combined in user space, then it can be analyzed by perf tools. Inspired-by: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Arun Sharma <asharma@fb.com> Signed-off-by: Andrew Vagin <avagin@openvz.org> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1342016098-213063-1-git-send-email-avagin@openvz.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-07-31ftrace: add ftrace_set_filter_ip() for address based filterMasami Hiramatsu
Add a new filter update interface ftrace_set_filter_ip() to set ftrace filter by ip address, not only glob pattern. Link: http://lkml.kernel.org/r/20120605102808.27845.67952.stgit@localhost.localdomain Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: "Frank Ch. Eigler" <fche@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-07-31ftrace: Add selftest to test function save-regs supportSteven Rostedt
Add selftests to test the save-regs functionality of ftrace. If the arch supports saving regs, then it will make sure that regs is at least not NULL in the callback. If the arch does not support saving regs, it makes sure that the registering of the ftrace_ops that requests saving regs fails. It then tests the registering of the ftrace_ops succeeds if the 'IF_SUPPORTED' flag is set. Then it makes sure that the regs passed to the function is NULL. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-07-31ftrace: Add selftest to test function trace recursion protectionSteven Rostedt
Add selftests to test the function tracing recursion protection actually does work. It also tests if a ftrace_ops states it will perform its own protection. Although, even if the ftrace_ops states it will protect itself, the ftrace infrastructure may still provide protection if the arch does not support all features or another ftrace_ops is registered. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-07-31ftrace: Only compile ftrace selftest if selftests are enabledSteven Rostedt
No need to compile in the ftrace selftest helper file if selftests are not being executed. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-07-31ftrace: Add default recursion protection for function tracingSteven Rostedt
As more users of the function tracer utility are being added, they do not always add the necessary recursion protection. To protect from function recursion due to tracing, if the callback ftrace_ops does not specifically specify that it protects against recursion (by setting the FTRACE_OPS_FL_RECURSION_SAFE flag), the list operation will be called by the mcount trampoline which adds recursion protection. If the flag is set, then the function will be called directly with no extra protection. Note, the list operation is called if more than one function callback is registered, or if the arch does not support all of the function tracer features. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-07-26Merge tag 'staging-3.6-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging Pull staging tree patches from Greg Kroah-Hartman: "Here's the big staging tree merge for the 3.6-rc1 merge window. There are some patches in here outside of drivers/staging/, notibly the iio code (which is still stradeling the staging / not staging boundry), the pstore code, and the tracing code. All of these have gotten acks from the various subsystem maintainers to be included in this tree. The pstore and tracing patches are related, and are coming here as they replace one of the android staging drivers. Otherwise, the normal staging mess. Lots of cleanups and a few new drivers (some iio drivers, and the large csr wireless driver abomination.) Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>" Fixed up trivial conflicts in drivers/staging/comedi/drivers/s626.h and drivers/staging/gdm72xx/netlink_k.c * tag 'staging-3.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (1108 commits) staging: csr: delete a bunch of unused library functions staging: csr: remove csr_utf16.c staging: csr: remove csr_pmem.h staging: csr: remove CsrPmemAlloc staging: csr: remove CsrPmemFree() staging: csr: remove CsrMemAllocDma() staging: csr: remove CsrMemCalloc() staging: csr: remove CsrMemAlloc() staging: csr: remove CsrMemFree() and CsrMemFreeDma() staging: csr: remove csr_util.h staging: csr: remove CsrOffSetOf() stating: csr: remove unneeded #includes in csr_util.c staging: csr: make CsrUInt16ToHex static staging: csr: remove CsrMemCpy() staging: csr: remove CsrStrLen() staging: csr: remove CsrVsnprintf() staging: csr: remove CsrStrDup staging: csr: remove CsrStrChr() staging: csr: remove CsrStrNCmp staging: csr: remove CsrStrCmp ...
2012-07-19ftrace/x86: Add separate function to save regsSteven Rostedt
Add a way to have different functions calling different trampolines. If a ftrace_ops wants regs saved on the return, then have only the functions with ops registered to save regs. Functions registered by other ops would not be affected, unless the functions overlap. If one ftrace_ops registered functions A, B and C and another ops registered fucntions to save regs on A, and D, then only functions A and D would be saving regs. Function B and C would work as normal. Although A is registered by both ops: normal and saves regs; this is fine as saving the regs is needed to satisfy one of the ops that calls it but the regs are ignored by the other ops function. x86_64 implements the full regs saving, and i386 just passes a NULL for regs to satisfy the ftrace_ops passing. Where an arch must supply both regs and ftrace_ops parameters, even if regs is just NULL. It is OK for an arch to pass NULL regs. All function trace users that require regs passing must add the flag FTRACE_OPS_FL_SAVE_REGS when registering the ftrace_ops. If the arch does not support saving regs then the ftrace_ops will fail to register. The flag FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED may be set that will prevent the ftrace_ops from failing to register. In this case, the handler may either check if regs is not NULL or check if ARCH_SUPPORTS_FTRACE_SAVE_REGS. If the arch supports passing regs it will set this macro and pass regs for ops that request them. All other archs will just pass NULL. Link: Link: http://lkml.kernel.org/r/20120711195745.107705970@goodmis.org Cc: Alexander van Heukelum <heukelum@fastmail.fm> Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-07-19ftrace: Return pt_regs to function trace callbackSteven Rostedt
Return as the 4th paramater to the function tracer callback the pt_regs. Later patches that implement regs passing for the architectures will require having the ftrace_ops set the SAVE_REGS flag, which will tell the arch to take the time to pass a full set of pt_regs to the ftrace_ops callback function. If the arch does not support it then it should pass NULL. If an arch can pass full regs, then it should define: ARCH_SUPPORTS_FTRACE_SAVE_REGS to 1 Link: http://lkml.kernel.org/r/20120702201821.019966811@goodmis.org Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-07-19ftrace: Consolidate arch dependent functions with 'list' functionSteven Rostedt
As the function tracer starts to get more features, the support for theses features will spread out throughout the different architectures over time. These features boil down to what each arch does in the mcount trampoline (the ftrace_caller). Currently there's two features that are not the same throughout the archs. 1) Support to stop function tracing before the callback 2) passing of the ftrace ops Both of these require placing an indirect function to support the features if the mcount trampoline does not. On a side note, for all architectures, when more than one callback is registered to the function tracer, an intermediate 'list' function is called by the mcount trampoline to iterate through the callbacks that are registered. Instead of making a separate function for each of these features, and requiring several indirect calls, just use the single 'list' function as the intermediate, to handle all cases. If an arch does not support the 'stop function tracing' or the passing of ftrace ops, just force it to use the list function that will handle the features required. This makes the code cleaner and simpler and removes a lot of #ifdefs in the code. Link: http://lkml.kernel.org/r/20120612225424.495625483@goodmis.org Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-07-19ftrace: Pass ftrace_ops as third parameter to function trace callbackSteven Rostedt
Currently the function trace callback receives only the ip and parent_ip of the function that it traced. It would be more powerful to also return the ops that registered the function as well. This allows the same function to act differently depending on what ftrace_ops registered it. Link: http://lkml.kernel.org/r/20120612225424.267254552@goodmis.org Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-07-18Merge branch 'tip/perf/core' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace into perf/core Pull tracing fix from Steve Rostedt. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-07-18Merge branch 'linus' into perf/coreIngo Molnar
Pick up the latest ring-buffer fixes, before applying a new fix. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-07-17tracing/function: Convert func_set_flag() to a switch statementAnton Vorontsov
Since the function accepts just one bit, we can use the switch construction instead of if/else if/... Just a cosmetic change, there should be no functional changes. Suggested-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-17tracing/function: Introduce persistent trace optionAnton Vorontsov
This patch introduces 'func_ptrace' option, now available in /sys/kernel/debug/tracing/options when function tracer is selected. The patch also adds some tiny code that calls back to pstore to record the trace. The callback is no-op when PSTORE=n. Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-17tracing: Fix initialization failure path in tracing_set_tracer()Anton Vorontsov
If tracer->init() fails, current code will leave current_tracer pointing to an unusable tracer, which at best makes 'current_tracer' report inaccurate value. Fix the issue by pointing current_tracer to nop tracer, and only update current_tracer with the new one after all the initialization succeeds. Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-14Merge branches 'core-urgent-for-linus', 'perf-urgent-for-linus' and ↵Linus Torvalds
'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RCU, perf, and scheduler fixes from Ingo Molnar. The RCU fix is a revert for an optimization that could cause deadlocks. One of the scheduler commits (164c33c6adee "sched: Fix fork() error path to not crash") is correct but not complete (some architectures like Tile are not covered yet) - the resulting additional fixes are still WIP and Ingo did not want to delay these pending fixes. See this thread on lkml: [PATCH] fork: fix error handling in dup_task() The perf fixes are just trivial oneliners. * 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: Revert "rcu: Move PREEMPT_RCU preemption to switch_to() invocation" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf kvm: Fix segfault with report and mixed guestmount use perf kvm: Fix regression with guest machine creation perf script: Fix format regression due to libtraceevent merge ring-buffer: Fix accounting of entries when removing pages ring-buffer: Fix crash due to uninitialized new_pages list head * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: MAINTAINERS/sched: Update scheduler file pattern sched/nohz: Rewrite and fix load-avg computation -- again sched: Fix fork() error path to not crash
2012-07-11tracing: Check for allocation failure in __tracing_open()Dan Carpenter
Clean up and return -ENOMEM on if the kzalloc() fails. This also prevents a potential crash, as the pointer that failed to allocate would be later used. Link: http://lkml.kernel.org/r/20120711063507.GF11812@elgon.mountain Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-07-06Merge branch 'tip/perf/core' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace into perf/core Pull tracing updates from Steve Rostedt. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-07-05Merge branch 'perf/urgent' into perf/coreIngo Molnar
Merge this branch to pick up a fixlet and to update to a more recent base. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-07-03Merge branch 'for-linus' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block bits from Jens Axboe: "As vacation is coming up, thought I'd better get rid of my pending changes in my for-linus branch for this iteration. It contains: - Two patches for mtip32xx. Killing a non-compliant sysfs interface and moving it to debugfs, where it belongs. - A few patches from Asias. Two legit bug fixes, and one killing an interface that is no longer in use. - A patch from Jan, making the annoying partition ioctl warning a bit less annoying, by restricting it to !CAP_SYS_RAWIO only. - Three bug fixes for drbd from Lars Ellenberg. - A fix for an old regression for umem, it hasn't really worked since the plugging scheme was changed in 3.0. - A few fixes from Tejun. - A splice fix from Eric Dumazet, fixing an issue with pipe resizing." * 'for-linus' of git://git.kernel.dk/linux-block: scsi: Silence unnecessary warnings about ioctl to partition block: Drop dead function blk_abort_queue() block: Mitigate lock unbalance caused by lock switching block: Avoid missed wakeup in request waitqueue umem: fix up unplugging splice: fix racy pipe->buffers uses drbd: fix null pointer dereference with on-congestion policy when diskless drbd: fix list corruption by failing but already aborted reads drbd: fix access of unallocated pages and kernel panic xen/blkfront: Add WARN to deal with misbehaving backends. blkcg: drop local variable @q from blkg_destroy() mtip32xx: Create debugfs entries for troubleshooting mtip32xx: Remove 'registers' and 'flags' from sysfs blkcg: fix blkg_alloc() failure path block: blkcg_policy_cfq shouldn't be used if !CONFIG_CFQ_GROUP_IOSCHED block: fix return value on cfq_init() failure mtip32xx: Remove version.h header file inclusion xen/blkback: Copy id field when doing BLKIF_DISCARD.
2012-06-29ring-buffer: Fix accounting of entries when removing pagesVaibhav Nagarnaik
When removing pages from the ring buffer, its state is not reset. This means that the counters need to be correctly updated to account for the pages removed. Update the overrun counter to reflect the removed events from the pages. Link: http://lkml.kernel.org/r/1340998301-1715-1-git-send-email-vnagarnaik@google.com Cc: Justin Teravest <teravest@google.com> Cc: David Sharp <dhsharp@google.com> Signed-off-by: Vaibhav Nagarnaik <vnagarnaik@google.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-06-29ring-buffer: Fix crash due to uninitialized new_pages list headVaibhav Nagarnaik
The new_pages list head in the cpu_buffer is not initialized. When adding pages to the ring buffer, if the memory allocation fails in ring_buffer_resize, the clean up handler tries to free up the allocated pages from all the cpu buffers. The panic is caused by referencing the uninitialized new_pages list head. Initializing the new_pages list head in rb_allocate_cpu_buffer fixes this. Link: http://lkml.kernel.org/r/1340391005-10880-1-git-send-email-vnagarnaik@google.com Cc: Justin Teravest <teravest@google.com> Cc: David Sharp <dhsharp@google.com> Signed-off-by: Vaibhav Nagarnaik <vnagarnaik@google.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-06-28ring-buffer: Fix uninitialized read_stampSteven Rostedt
The ring buffer reader page is used to swap a page from the writable ring buffer. If the writer happens to be on that page, it ends up on the reader page, but will simply move off of it, back into the writable ring buffer as writes are added. The time stamp passed back to the readers is stored in the cpu_buffer per CPU descriptor. This stamp is updated when a swap of the reader page takes place, and it reads the current stamp from the page taken from the writable ring buffer. Everytime a writer goes to a new page, it updates the time stamp of that page. The problem happens if a reader reads a page from an empty per CPU ring buffer. If the buffer is empty, the swap still takes place, placing the writer at the start of the reader page. If at a later time, a write happens, it updates the page's time stamp and continues. But the problem is that the read_stamp does not get updated, because the page was already swapped. The solution to this was to not swap the page if the ring buffer happens to be empty. This also removes the side effect that the writes on the reader page will not get updated because the writer never gets back on the reader page without a swap. That is, if a read happens on an empty buffer, but then no reads happen for a while. If a swap took place, and the writer were to start writing a lot of data (function tracer), it will start overflowing the ring buffer and overwrite the older data. But because the writer never goes back onto the reader page, the data left on the reader page never gets overwritten. This causes the reader to see really old data, followed by a jump to newer data. Link: http://lkml.kernel.org/r/1340060577-9112-1-git-send-email-dhsharp@google.com Google-Bug-Id: 6410455 Reported-by: David Sharp <dhsharp@google.com> tested-by: David Sharp <dhsharp@google.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-06-28tracing: Remove NR_CPUS array from trace_iteratorSteven Rostedt
Replace the NR_CPUS array of buffer_iter from the trace_iterator with an allocated array. This will just create an array of possible CPUS instead of the max number specified. The use of NR_CPUS in that array caused allocation failures for machines that were tight on memory. This did not cause any failures to the system itself (no crashes), but caused unnecessary failures for reading the trace files. Added a helper function called 'trace_buffer_iter()' that returns the buffer_iter item or NULL if it is not defined or the array was not allocated. Some routines do not require the array (tracing_open_pipe() for one). Reported-by: Dave Jones <davej@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-06-28tracing/selftest: Add a WARN_ON() if a tracer test failsSteven Rostedt
Add a WARN_ON() output on test failures so that they are easier to detect in automated tests. Although, the WARN_ON() will not print if the test causes the system to crash, obviously. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-06-18Merge branch 'perf/urgent' into perf/coreIngo Molnar
Merge in all fixes before applying more changes. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-06-14tracing: Register the ftrace internal events during early bootSteven Rostedt
All trace events including ftrace internel events (like trace_printk and function tracing), register functions that describe how to print their output. The events may be recorded as soon as the ring buffer is allocated, but they are just raw binary in the buffer. The mapping of event ids to how to print them are held within a structure that is registered on system boot. If a crash happens in boot up before these functions are registered then their output (via ftrace_dump_on_oops) will be useless: Dumping ftrace buffer: --------------------------------- <...>-1 0.... 319705us : Unknown type 6 --------------------------------- This can be quite frustrating for a kernel developer trying to see what is going wrong. There's no reason to register them so late in the boot up process. They can be registered by early_initcall(). Reported-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-06-14ftrace: Remove a superfluous checkBorislav Petkov
register_ftrace_function() checks ftrace_disabled and calls __register_ftrace_function which does it again. Drop the first check and add the unlikely hint to the second one. Also, drop the label as John correctly notices. No functional change. Link: http://lkml.kernel.org/r/20120329171140.GE6409@aftab Cc: Borislav Petkov <bp@amd64.org> Cc: John Kacur <jkacur@redhat.com> Signed-off-by: Borislav Petkov <borislav.petkov@amd.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>