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* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netHEADmasterLinus Torvalds2018-04-24
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull networking fixes from David Miller: 1) Fix rtnl deadlock in ipvs, from Julian Anastasov. 2) s390 qeth fixes from Julian Wiedmann (control IO completion stalls, bad MAC address update sequence, request side races on command IO timeouts). 3) Handle seq_file overflow properly in l2tp, from Guillaume Nault. 4) Fix VLAN priority mappings in cpsw driver, from Ivan Khoronzhuk. 5) Packet scheduler ife action fixes (malformed TLV lengths, etc.) from Alexander Aring. 6) Fix out of bounds access in tcp md5 option parser, from Jann Horn. 7) Missing netlink attribute policies in rtm_ipv6_policy table, from Eric Dumazet. 8) Missing socket address length checks in l2tp and pppoe connect, from Guillaume Nault. 9) Fix netconsole over team and bonding, from Xin Long. 10) Fix race with AF_PACKET socket state bitfields, from Willem de Bruijn. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (51 commits) ice: Fix insufficient memory issue in ice_aq_manage_mac_read sfc: ARFS filter IDs net: ethtool: Add missing kernel doc for FEC parameters packet: fix bitfield update race ice: Do not check INTEVENT bit for OICR interrupts ice: Fix incorrect comment for action type ice: Fix initialization for num_nodes_added igb: Fix the transmission mode of queue 0 for Qav mode ixgbevf: ensure xdp_ring resources are free'd on error exit team: fix netconsole setup over team amd-xgbe: Only use the SFP supported transceiver signals amd-xgbe: Improve KR auto-negotiation and training amd-xgbe: Add pre/post auto-negotiation phy hooks pppoe: check sockaddr length in pppoe_connect() l2tp: check sockaddr length in pppol2tp_connect() net: phy: marvell: clear wol event before setting it ipv6: add RTA_TABLE and RTA_PREFSRC to rtm_ipv6_policy bonding: do not set slave_dev npinfo before slave_enable_netpoll in bond_enslave tcp: don't read out-of-bounds opsize ibmvnic: Clean actual number of RX or TX pools ...
| * Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpfDavid S. Miller2018-04-22
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Daniel Borkmann says: ==================== pull-request: bpf 2018-04-21 The following pull-request contains BPF updates for your *net* tree. The main changes are: 1) Fix a deadlock between mm->mmap_sem and bpf_event_mutex when one task is detaching a BPF prog via perf_event_detach_bpf_prog() and another one dumping through bpf_prog_array_copy_info(). For the latter we move the copy_to_user() out of the bpf_event_mutex lock to fix it, from Yonghong. 2) Fix test_sock and test_sock_addr.sh failures. The former was hitting rlimit issues and the latter required ping to specify the address family, from Yonghong. 3) Remove a dead check in sockmap's sock_map_alloc(), from Jann. 4) Add generated files to BPF kselftests gitignore that were previously missed, from Anders. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
| | * bpf/tracing: fix a deadlock in perf_event_detach_bpf_progYonghong Song2018-04-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | syzbot reported a possible deadlock in perf_event_detach_bpf_prog. The error details: ====================================================== WARNING: possible circular locking dependency detected 4.16.0-rc7+ #3 Not tainted ------------------------------------------------------ syz-executor7/24531 is trying to acquire lock: (bpf_event_mutex){+.+.}, at: [<000000008a849b07>] perf_event_detach_bpf_prog+0x92/0x3d0 kernel/trace/bpf_trace.c:854 but task is already holding lock: (&mm->mmap_sem){++++}, at: [<0000000038768f87>] vm_mmap_pgoff+0x198/0x280 mm/util.c:353 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&mm->mmap_sem){++++}: __might_fault+0x13a/0x1d0 mm/memory.c:4571 _copy_to_user+0x2c/0xc0 lib/usercopy.c:25 copy_to_user include/linux/uaccess.h:155 [inline] bpf_prog_array_copy_info+0xf2/0x1c0 kernel/bpf/core.c:1694 perf_event_query_prog_array+0x1c7/0x2c0 kernel/trace/bpf_trace.c:891 _perf_ioctl kernel/events/core.c:4750 [inline] perf_ioctl+0x3e1/0x1480 kernel/events/core.c:4770 vfs_ioctl fs/ioctl.c:46 [inline] do_vfs_ioctl+0x1b1/0x1520 fs/ioctl.c:686 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x42/0xb7 -> #0 (bpf_event_mutex){+.+.}: lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:3920 __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0x16f/0x1a80 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 perf_event_detach_bpf_prog+0x92/0x3d0 kernel/trace/bpf_trace.c:854 perf_event_free_bpf_prog kernel/events/core.c:8147 [inline] _free_event+0xbdb/0x10f0 kernel/events/core.c:4116 put_event+0x24/0x30 kernel/events/core.c:4204 perf_mmap_close+0x60d/0x1010 kernel/events/core.c:5172 remove_vma+0xb4/0x1b0 mm/mmap.c:172 remove_vma_list mm/mmap.c:2490 [inline] do_munmap+0x82a/0xdf0 mm/mmap.c:2731 mmap_region+0x59e/0x15a0 mm/mmap.c:1646 do_mmap+0x6c0/0xe00 mm/mmap.c:1483 do_mmap_pgoff include/linux/mm.h:2223 [inline] vm_mmap_pgoff+0x1de/0x280 mm/util.c:355 SYSC_mmap_pgoff mm/mmap.c:1533 [inline] SyS_mmap_pgoff+0x462/0x5f0 mm/mmap.c:1491 SYSC_mmap arch/x86/kernel/sys_x86_64.c:100 [inline] SyS_mmap+0x16/0x20 arch/x86/kernel/sys_x86_64.c:91 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x42/0xb7 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&mm->mmap_sem); lock(bpf_event_mutex); lock(&mm->mmap_sem); lock(bpf_event_mutex); *** DEADLOCK *** ====================================================== The bug is introduced by Commit f371b304f12e ("bpf/tracing: allow user space to query prog array on the same tp") where copy_to_user, which requires mm->mmap_sem, is called inside bpf_event_mutex lock. At the same time, during perf_event file descriptor close, mm->mmap_sem is held first and then subsequent perf_event_detach_bpf_prog needs bpf_event_mutex lock. Such a senario caused a deadlock. As suggested by Daniel, moving copy_to_user out of the bpf_event_mutex lock should fix the problem. Fixes: f371b304f12e ("bpf/tracing: allow user space to query prog array on the same tp") Reported-by: syzbot+dc5ca0e4c9bfafaf2bae@syzkaller.appspotmail.com Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
* | | trace_kprobe: Remove warning message "Could not insert probe at..."Song Liu2018-04-17
|/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This warning message is not very helpful, as the return value should already show information about the error. Also, this message will spam dmesg if the user space does testing in a loop, like: for x in {0..5} do echo p:xx xx+$x >> /sys/kernel/debug/tracing/kprobe_events done Reported-by: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Song Liu <songliubraving@fb.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: kernel-team@fb.com Link: http://lkml.kernel.org/r/20180413185513.3626052-1-songliubraving@fb.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds2018-04-15
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull more perf updates from Thomas Gleixner: "A rather large set of perf updates: Kernel: - Fix various initialization issues - Prevent creating [ku]probes for not CAP_SYS_ADMIN users Tooling: - Show only failing syscalls with 'perf trace --failure' (Arnaldo Carvalho de Melo) e.g: See what 'openat' syscalls are failing: # perf trace --failure -e openat 762.323 ( 0.007 ms): VideoCapture/4566 openat(dfd: CWD, filename: /dev/video2) = -1 ENOENT No such file or directory <SNIP N /dev/videoN open attempts... sigh, where is that improvised camera lid?!? > 790.228 ( 0.008 ms): VideoCapture/4566 openat(dfd: CWD, filename: /dev/video63) = -1 ENOENT No such file or directory ^C# - Show information about the event (freq, nr_samples, total period/nr_events) in the annotate --tui and --stdio2 'perf annotate' output, similar to the first line in the 'perf report --tui', but just for the samples for a the annotated symbol (Arnaldo Carvalho de Melo) - Introduce 'perf version --build-options' to show what features were linked, aliased as well as a shorter 'perf -vv' (Jin Yao) - Add a "dso_size" sort order (Kim Phillips) - Remove redundant ')' in the tracepoint output in 'perf trace' (Changbin Du) - Synchronize x86's cpufeatures.h, no effect on toolss (Arnaldo Carvalho de Melo) - Show group details on the title line in the annotate browser and 'perf annotate --stdio2' output, so that the per-event columns can have headers (Arnaldo Carvalho de Melo) - Fixup vertical line separating metrics from instructions and cleaning unused lines at the bottom, both in the annotate TUI browser (Arnaldo Carvalho de Melo) - Remove duplicated 'samples' in lost samples warning in 'perf report' (Arnaldo Carvalho de Melo) - Synchronize i915_drm.h, silencing the perf build process, automagically adding support for the new DRM_I915_QUERY ioctl (Arnaldo Carvalho de Melo) - Make auxtrace_queues__add_buffer() allocate struct buffer, from a patchkit already applied (Adrian Hunter) - Fix the --stdio2/TUI annotate output to include group details, be it for a recorded '{a,b,f}' explicit event group or when forcing group display using 'perf report --group' for a set of events not recorded as a group (Arnaldo Carvalho de Melo) - Fix display artifacts in the ui browser (base class for the annotate and main report/top TUI browser) related to the extra title lines work (Arnaldo Carvalho de Melo) - perf auxtrace refactorings, leftovers from a previously partially processed patchset (Adrian Hunter) - Fix the builtin clang build (Sandipan Das, Arnaldo Carvalho de Melo) - Synchronize i915_drm.h, silencing a perf build warning and in the process automagically adding support for a new ioctl command (Arnaldo Carvalho de Melo) - Fix a strncpy issue in uprobe tracing" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits) perf/core: Need CAP_SYS_ADMIN to create k/uprobe with perf_event_open() tracing/uprobe_event: Fix strncpy corner case perf/core: Fix perf_uprobe_init() perf/core: Fix perf_kprobe_init() perf/core: Fix use-after-free in uprobe_perf_close() perf tests clang: Fix function name for clang IR test perf clang: Add support for recent clang versions perf tools: Fix perf builds with clang support perf tools: No need to include namespaces.h in util.h perf hists browser: Remove leftover from row returned from refresh perf hists browser: Show extra_title_lines in the 'D' debug hotkey perf auxtrace: Make auxtrace_queues__add_buffer() do CPU filtering tools headers uapi: Synchronize i915_drm.h perf report: Remove duplicated 'samples' in lost samples warning perf ui browser: Fixup cleaning unused lines at the bottom perf annotate browser: Fixup vertical line separating metrics from instructions perf annotate: Show group details on the title line perf auxtrace: Make auxtrace_queues__add_buffer() allocate struct buffer perf/x86/intel: Move regs->flags EXACT bit init perf trace: Remove redundant ')' ...
| * | tracing/uprobe_event: Fix strncpy corner caseMasami Hiramatsu2018-04-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix string fetch function to terminate with NUL. It is OK to drop the rest of string. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Song Liu <songliubraving@fb.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: security@kernel.org Cc: 范龙飞 <long7573@126.com> Fixes: 5baaa59ef09e ("tracing/probes: Implement 'memory' fetch method for uprobes") Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | perf/core: Fix perf_uprobe_init()Song Liu2018-04-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Similarly to the uprobe PMU fix in perf_kprobe_init(), fix error handling in perf_uprobe_init() as well. Reported-by: 范龙飞 <long7573@126.com> Signed-off-by: Song Liu <songliubraving@fb.com> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: e12f03d7031a ("perf/core: Implement the 'perf_kprobe' PMU") Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | perf/core: Fix perf_kprobe_init()Masami Hiramatsu2018-04-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix error handling in perf_kprobe_init(): ================================================================== BUG: KASAN: slab-out-of-bounds in strlen+0x8e/0xa0 lib/string.c:482 Read of size 1 at addr ffff88003f9cc5c0 by task syz-executor2/23095 CPU: 0 PID: 23095 Comm: syz-executor2 Not tainted 4.16.0+ #24 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0xca/0x13e lib/dump_stack.c:113 print_address_description+0x6e/0x2c0 mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report+0x256/0x380 mm/kasan/report.c:412 strlen+0x8e/0xa0 lib/string.c:482 kstrdup+0x21/0x70 mm/util.c:55 alloc_trace_kprobe+0xc8/0x930 kernel/trace/trace_kprobe.c:325 create_local_trace_kprobe+0x4f/0x3a0 kernel/trace/trace_kprobe.c:1438 perf_kprobe_init+0x149/0x1f0 kernel/trace/trace_event_perf.c:264 perf_kprobe_event_init+0xa8/0x120 kernel/events/core.c:8407 perf_try_init_event+0xcb/0x2a0 kernel/events/core.c:9719 perf_init_event kernel/events/core.c:9750 [inline] perf_event_alloc+0x1367/0x1e20 kernel/events/core.c:10022 SYSC_perf_event_open+0x242/0x2330 kernel/events/core.c:10477 do_syscall_64+0x198/0x640 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x42/0xb7 Reported-by: 范龙飞 <long7573@126.com> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Song Liu <songliubraving@fb.com> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: e12f03d7031a ("perf/core: Implement the 'perf_kprobe' PMU") Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | | Merge tag 'trace-v4.17-2' of ↵Linus Torvalds2018-04-12
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: "A few clean ups and bug fixes: - replace open coded "ARRAY_SIZE()" with macro - updates to uprobes - bug fix for perf event filter on error path" * tag 'trace-v4.17-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing: Enforce passing in filter=NULL to create_filter() trace_uprobe: Simplify probes_seq_show() trace_uprobe: Use %lx to display offset tracing/uprobe: Add support for overlayfs tracing: Use ARRAY_SIZE() macro instead of open coding it
| * | | tracing: Enforce passing in filter=NULL to create_filter()Steven Rostedt (VMware)2018-04-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There's some inconsistency with what to set the output parameter filterp when passing to create_filter(..., struct event_filter **filterp). Whatever filterp points to, should be NULL when calling this function. The create_filter() calls create_filter_start() with a pointer to a local "filter" variable that is set to NULL. The create_filter_start() has a WARN_ON() if the passed in pointer isn't pointing to a value set to NULL. Ideally, create_filter() should pass the filterp variable it received to create_filter_start() and not hide it as with a local variable, this allowed create_filter() to fail, and not update the passed in filter, and the caller of create_filter() then tried to free filter, which was never initialized to anything, causing memory corruption. Link: http://lkml.kernel.org/r/00000000000032a0c30569916870@google.com Fixes: 80765597bc587 ("tracing: Rewrite filter logic to be simpler and faster") Reported-by: syzbot+dadcc936587643d7f568@syzkaller.appspotmail.com Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | trace_uprobe: Simplify probes_seq_show()Ravi Bangoria2018-04-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Simplify probes_seq_show() function. No change in output before and after patch. Link: http://lkml.kernel.org/r/20180315082756.9050-2-ravi.bangoria@linux.vnet.ibm.com Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | trace_uprobe: Use %lx to display offsetRavi Bangoria2018-04-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | tu->offset is unsigned long, not a pointer, thus %lx should be used to print it, not the %px. Link: http://lkml.kernel.org/r/20180315082756.9050-1-ravi.bangoria@linux.vnet.ibm.com Cc: stable@vger.kernel.org Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Fixes: 0e4d819d0893 ("trace_uprobe: Display correct offset in uprobe_events") Suggested-by: Kees Cook <keescook@chromium.org> Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | tracing/uprobe: Add support for overlayfsHoward McLauchlan2018-04-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | uprobes cannot successfully attach to binaries located in a directory mounted with overlayfs. To verify, create directories for mounting overlayfs (upper,lower,work,merge), move some binary into merge/ and use readelf to obtain some known instruction of the binary. I used /bin/true and the entry instruction(0x13b0): $ mount -t overlay overlay -o lowerdir=lower,upperdir=upper,workdir=work merge $ cd /sys/kernel/debug/tracing $ echo 'p:true_entry PATH_TO_MERGE/merge/true:0x13b0' > uprobe_events $ echo 1 > events/uprobes/true_entry/enable This returns 'bash: echo: write error: Input/output error' and dmesg tells us 'event trace: Could not enable event true_entry' This change makes create_trace_uprobe() look for the real inode of a dentry. In the case of normal filesystems, this simplifies to just returning the inode. In the case of overlayfs(and similar fs) we will obtain the underlying dentry and corresponding inode, upon which uprobes can successfully register. Running the example above with the patch applied, we can see that the uprobe is enabled and will output to trace as expected. Link: http://lkml.kernel.org/r/20180410231030.2720-1-hmclauchlan@fb.com Reviewed-by: Josef Bacik <jbacik@fb.com> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Howard McLauchlan <hmclauchlan@fb.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | tracing: Use ARRAY_SIZE() macro instead of open coding itJérémy Lefaure2018-04-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It is useless to re-invent the ARRAY_SIZE macro so let's use it instead of DATA_CNT. Found with Coccinelle with the following semantic patch: @r depends on (org || report)@ type T; T[] E; position p; @@ ( (sizeof(E)@p /sizeof(*E)) | (sizeof(E)@p /sizeof(E[...])) | (sizeof(E)@p /sizeof(T)) ) Link: http://lkml.kernel.org/r/20171016012250.26453-1-jeremy.lefaure@lse.epita.fr Signed-off-by: Jérémy Lefaure <jeremy.lefaure@lse.epita.fr> [ Removed useless include of kernel.h ] Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* | | | Merge tag 'trace-v4.17' of ↵Linus Torvalds2018-04-10
|\ \ \ \ | |/ / / | | | / | |_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: "New features: - Tom Zanussi's extended histogram work. This adds the synthetic events to have histograms from multiple event data Adds triggers "onmatch" and "onmax" to call the synthetic events Several updates to the histogram code from this - Allow way to nest ring buffer calls in the same context - Allow absolute time stamps in ring buffer - Rewrite of filter code parsing based on Al Viro's suggestions - Setting of trace_clock to global if TSC is unstable (on boot) - Better OOM handling when allocating large ring buffers - Added initcall tracepoints (consolidated initcall_debug code with them) And other various fixes and clean ups" * tag 'trace-v4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (68 commits) init: Have initcall_debug still work without CONFIG_TRACEPOINTS init, tracing: Have printk come through the trace events for initcall_debug init, tracing: instrument security and console initcall trace events init, tracing: Add initcall trace events tracing: Add rcu dereference annotation for test func that touches filter->prog tracing: Add rcu dereference annotation for filter->prog tracing: Fixup logic inversion on setting trace_global_clock defaults tracing: Hide global trace clock from lockdep ring-buffer: Add set/clear_current_oom_origin() during allocations ring-buffer: Check if memory is available before allocation lockdep: Add print_irqtrace_events() to __warn vsprintf: Do not preprocess non-dereferenced pointers for bprintf (%px and %pK) tracing: Uninitialized variable in create_tracing_map_fields() tracing: Make sure variable string fields are NULL-terminated tracing: Add action comparisons when testing matching hist triggers tracing: Don't add flag strings when displaying variable references tracing: Fix display of hist trigger expressions containing timestamps ftrace: Drop a VLA in module_exists() tracing: Mention trace_clock=global when warning about unstable clocks tracing: Default to using trace_global_clock if sched_clock is unstable ...
| * | tracing: Add rcu dereference annotation for test func that touches filter->progSteven Rostedt (VMware)2018-04-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A boot up test function update_pred_fn() dereferences filter->prog without the proper rcu annotation. To do this, we must also take the event_mutex first. Normally, this isn't needed because this test function can not race with other use cases that touch the event filters (it is disabled if any events are enabled). Reported-by: kbuild test robot <fengguang.wu@intel.com> Fixes: 80765597bc587 ("tracing: Rewrite filter logic to be simpler and faster") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | tracing: Add rcu dereference annotation for filter->progSteven Rostedt (VMware)2018-04-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ftrace_function_set_filter() referenences filter->prog without annotation and sparse complains about it. It needs a rcu_dereference_protected() wrapper. Reported-by: kbuild test robot <fengguang.wu@intel.com> Fixes: 80765597bc587 ("tracing: Rewrite filter logic to be simpler and faster") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | tracing: Fixup logic inversion on setting trace_global_clock defaultsChris Wilson2018-04-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In commit 932066a15335 ("tracing: Default to using trace_global_clock if sched_clock is unstable"), the logic for deciding to override the default clock if unstable was reversed from the earlier posting. I was trying to reduce the width of the message by using an early return rather than a if-block, but reverted back to using the if-block and accidentally left the predicate inverted. Link: http://lkml.kernel.org/r/20180404212450.26646-1-chris@chris-wilson.co.uk Fixes: 932066a15335 ("tracing: Default to using trace_global_clock if sched_clock is unstable") Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | tracing: Hide global trace clock from lockdepSteven Rostedt (VMware)2018-04-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Function tracing can trace in NMIs and such. If the TSC is determined to be unstable, the tracing clock will switch to the global clock on boot up, unless "trace_clock" is specified on the kernel command line. The global clock disables interrupts to access sched_clock_cpu(), and in doing so can be done within lockdep internals (because of function tracing and NMIs). This can trigger false lockdep splats. The trace_clock_global() is special, best not to trace the irq logic within it. Link: http://lkml.kernel.org/r/20180404145015.77bde42d@gandalf.local.home Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | ring-buffer: Add set/clear_current_oom_origin() during allocationsSteven Rostedt (VMware)2018-04-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As si_mem_available() can say there is enough memory even though the memory available is not useable by the ring buffer, it is best to not kill innocent applications because the ring buffer is taking up all the memory while it is trying to allocate a great deal of memory. If the allocator is user space (because kernel threads can also increase the size of the kernel ring buffer on boot up), then after si_mem_available() says there is enough memory, set the OOM killer to kill the current task if an OOM triggers during the allocation. Link: http://lkml.kernel.org/r/20180404062340.GD6312@dhcp22.suse.cz Suggested-by: Michal Hocko <mhocko@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | ring-buffer: Check if memory is available before allocationSteven Rostedt (VMware)2018-04-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The ring buffer is made up of a link list of pages. When making the ring buffer bigger, it will allocate all the pages it needs before adding to the ring buffer, and if it fails, it frees them and returns an error. This makes increasing the ring buffer size an all or nothing action. When this was first created, the pages were allocated with "NORETRY". This was to not cause any Out-Of-Memory (OOM) actions from allocating the ring buffer. But NORETRY was too strict, as the ring buffer would fail to expand even when there's memory available, but was taken up in the page cache. Commit 848618857d253 ("tracing/ring_buffer: Try harder to allocate") changed the allocating from NORETRY to RETRY_MAYFAIL. The RETRY_MAYFAIL would allocate from the page cache, but if there was no memory available, it would simple fail the allocation and not trigger an OOM. This worked fine, but had one problem. As the ring buffer would allocate one page at a time, it could take up all memory in the system before it failed to allocate and free that memory. If the allocation is happening and the ring buffer allocates all memory and then tries to take more than available, its allocation will not trigger an OOM, but if there's any allocation that happens someplace else, that could trigger an OOM, even though once the ring buffer's allocation fails, it would free up all the previous memory it tried to allocate, and allow other memory allocations to succeed. Commit d02bd27bd33dd ("mm/page_alloc.c: calculate 'available' memory in a separate function") separated out si_mem_availble() as a separate function that could be used to see how much memory is available in the system. Using this function to make sure that the ring buffer could be allocated before it tries to allocate pages we can avoid allocating all memory in the system and making it vulnerable to OOMs if other allocations are taking place. Link: http://lkml.kernel.org/r/1522320104-6573-1-git-send-email-zhaoyang.huang@spreadtrum.com CC: stable@vger.kernel.org Cc: linux-mm@kvack.org Fixes: 848618857d253 ("tracing/ring_buffer: Try harder to allocate") Requires: d02bd27bd33dd ("mm/page_alloc.c: calculate 'available' memory in a separate function") Reported-by: Zhaoyang Huang <huangzhaoyang@gmail.com> Tested-by: Joel Fernandes <joelaf@google.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | tracing: Uninitialized variable in create_tracing_map_fields()Dan Carpenter2018-04-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Smatch complains that idx can be used uninitialized when we check if (idx < 0). It has to be the first iteration through the loop and the HIST_FIELD_FL_STACKTRACE bit has to be clear and the HIST_FIELD_FL_VAR bit has to be set to reach the bug. Link: http://lkml.kernel.org/r/20180328114815.GC29050@mwanda Fixes: 30350d65ac56 ("tracing: Add variable support to hist triggers") Acked-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | tracing: Make sure variable string fields are NULL-terminatedTom Zanussi2018-04-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The strncpy() currently being used for variable string fields can result in a lack of termination if the string length is equal to the field size. Use the safer strscpy() instead, which will guarantee termination. Link: http://lkml.kernel.org/r/fb97c1e518fb358c12a4057d7445ba2c46956cd7.1522256721.git.tom.zanussi@linux.intel.com Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | tracing: Add action comparisons when testing matching hist triggersTom Zanussi2018-04-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Actions also need to be considered when checking for matching triggers - triggers differing only by action should be allowed, but currently aren't because the matching check ignores the action and erroneously returns -EEXIST. Add and call an actions_match() function to address that. Here's an example using onmatch() actions. The first -EEXIST shouldn't occur because the onmatch() is different in the second wakeup_latency() param. The second -EEXIST shouldn't occur because it's a different action (in this case, it doesn't have an action, so shouldn't be seen as being the same and therefore rejected). In the after case, both are correctly accepted (and trying to add one of them again returns -EEXIST as it should). before: # echo 'wakeup_latency u64 lat; pid_t pid' >> /sys/kernel/debug/tracing/synthetic_events # echo 'hist:keys=pid:ts0=common_timestamp.usecs if comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger # echo 'hist:keys=next_pid:wakeup_lat=common_timestamp.usecs-$ts0 if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger # echo 'hist:keys=next_pid:onmatch(sched.sched_wakeup).wakeup_latency(sched.sched_switch.$wakeup_lat,next_pid) if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger # echo 'hist:keys=next_pid:onmatch(sched.sched_wakeup).wakeup_latency(sched.sched_switch.$wakeup_lat,prev_pid) if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger -su: echo: write error: File exists # echo 'hist:keys=next_pid if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger -su: echo: write error: File exists after: # echo 'wakeup_latency u64 lat; pid_t pid' >> /sys/kernel/debug/tracing/synthetic_events # echo 'hist:keys=pid:ts0=common_timestamp.usecs if comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger # echo 'hist:keys=next_pid:wakeup_lat=common_timestamp.usecs-$ts0 if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger # echo 'hist:keys=next_pid:onmatch(sched.sched_wakeup).wakeup_latency(sched.sched_switch.$wakeup_lat,next_pid) if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger # echo 'hist:keys=next_pid:onmatch(sched.sched_wakeup).wakeup_latency(sched.sched_switch.$wakeup_lat,prev_pid) if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger # echo 'hist:keys=next_pid if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger Link: http://lkml.kernel.org/r/a7fd668b87ec10736c8f016ac4279c8480d50c2b.1522256721.git.tom.zanussi@linux.intel.com Tested-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | tracing: Don't add flag strings when displaying variable referencesTom Zanussi2018-04-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Variable references should never have flags appended when displayed - prevent that from happening. Before: # cat /sys/kernel/debug/tracing/events/sched/sched_switch/trigger hist:keys=next_pid:vals=hitcount:wakeup_lat=common_timestamp.usecs-$ts0.usecs:... After: hist:keys=next_pid:vals=hitcount:wakeup_lat=common_timestamp.usecs-$ts0:... Link: http://lkml.kernel.org/r/913318a5610ef6b24af2522575f671fa6ee19b6b.1522256721.git.tom.zanussi@linux.intel.com Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | tracing: Fix display of hist trigger expressions containing timestampsTom Zanussi2018-04-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When displaying hist triggers, variable references that have the timestamp field flag set are erroneously displayed as common_timestamp rather than the variable reference. Additionally, timestamp expressions are displayed in the same way. Fix this by forcing the timestamp flag handling to follow variable reference and expression handling. Before: # cat /sys/kernel/debug/tracing/events/sched/sched_switch/trigger hist:keys=next_pid:vals=hitcount:wakeup_lat=common_timestamp.usecs:... After: # cat /sys/kernel/debug/tracing/events/sched/sched_switch/trigger hist:keys=next_pid:vals=hitcount:wakeup_lat=common_timestamp.usecs-$ts0.usecs:... Link: http://lkml.kernel.org/r/92746b06be67499c2a6217bd55395b350ad18fad.1522256721.git.tom.zanussi@linux.intel.com Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | ftrace: Drop a VLA in module_exists()Salvatore Mesoraca2018-04-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Avoid a VLA by using a real constant expression instead of a variable. The compiler should be able to optimize the original code and avoid using an actual VLA. Anyway this change is useful because it will avoid a false positive with -Wvla, it might also help the compiler generating better code. Link: http://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com Link: http://lkml.kernel.org/r/1522399988-8815-1-git-send-email-s.mesoraca16@gmail.com Signed-off-by: Salvatore Mesoraca <s.mesoraca16@gmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | tracing: Mention trace_clock=global when warning about unstable clocksChris Wilson2018-04-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Mention the alternative of adding trace_clock=global to the kernel command line when we detect that we've used an unstable clock across a suspend/resume cycle. Link: http://lkml.kernel.org/r/20180330150132.16903-2-chris@chris-wilson.co.uk Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | tracing: Default to using trace_global_clock if sched_clock is unstableChris Wilson2018-04-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Across suspend, we may see a very large drift in timestamps if the sched clock is unstable, prompting the global trace's ringbuffer code to warn and suggest switching to the global clock. Preempt this request by detecting when the sched clock is unstable (determined during late_initcall) and automatically switching the default clock over to trace_global_clock. This should prevent requiring user interaction to resolve warnings such as: Delta way too big! 18446743856563626466 ts=18446744054496180323 write stamp = 197932553857 If you just came from a suspend/resume, please switch to the trace global clock: echo global > /sys/kernel/debug/tracing/trace_clock Link: http://lkml.kernel.org/r/20180330150132.16903-1-chris@chris-wilson.co.uk Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | tracing: Fix a potential NULL dereferenceDan Carpenter2018-03-23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We forgot to set the error code on this path so we return ERR_PTR(0) which is NULL. It results in a NULL dereference in the caller. Link: http://lkml.kernel.org/r/20180323113735.GC28518@mwanda Fixes: 100719dcef44 ("tracing: Add simple expression support to hist triggers") Acked-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | tracing: Rewrite filter logic to be simpler and fasterSteven Rostedt (VMware)2018-03-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Al Viro reviewed the filter logic of ftrace trace events and found it to be very troubling. It creates a binary tree based on the logic operators and walks it during tracing. He sent myself and Tom Zanussi a long explanation (and formal proof) of how to do the string parsing better and end up with a program array that can be simply iterated to come up with the correct results. I took his ideas and his pseudo code and rewrote the filter logic based on them. In doing so, I was able to remove a lot of code, and have a much more condensed filter logic in the process. I wrote a very long comment describing the methadology that Al proposed in my own words. For more info on how this works, read the comment above predicate_parse(). Suggested-by: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | tracing: Clean up and document pred_funcs_##type creation and useSteven Rostedt (VMware)2018-03-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The pred_funcs_##type arrays consist of five functions that are assigned based on the ops. The array must be in the same order of the ops each function represents. The PRED_FUNC_START macro denotes the op enum that starts the op that maps to the pred_funcs_##type arrays. This is all very subtle and prone to bugs if the code is changed. Add comments describing how PRED_FUNC_START and pred_funcs_##type array is used, and also a PRED_FUNC_MAX that is the maximum number of functions in the arrays. Clean up select_comparison_fn() that assigns the predicates to the pred_funcs_##type array function as well as add protection in case an op is passed in that does not map correctly to the array. Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | tracing: Combine enum and arrays into single macro in filter codeSteven Rostedt (VMware)2018-03-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Instead of having a separate enum that is the index into another array, like a string array, make a single macro that combines them into a single list, and then the two can not get out of sync. This makes it easier to add and remove items. The macro trick is: #define DOGS \ C( JACK, "Jack Russell") \ C( ITALIAN, "Italian Greyhound") \ C( GERMAN, "German Shepherd") #undef C #define C(a, b) a enum { DOGS }; #undef C #define C(a, b) b static char dogs[] = { DOGS }; Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | tracing: Embed replace_filter_string() helper functionSteven Rostedt (VMware)2018-03-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The replace_filter_string() frees the current string and then copies a given string. But in the two locations that it was used, the allocation happened right after the filter was allocated (nothing to replace). There's no need for this to be a helper function. Embedding the allocation in the two places where it was called will make changing the code in the future easier. Also make the variable consistent (always use "filter_string" as the name, as it was used in one instance as "filter_str") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | tracing: Only add filter list when neededSteven Rostedt (VMware)2018-03-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | replace_system_preds() creates a filter list to free even when it doesn't really need to have it. Only save filters that require synchronize_sched() in the filter list to free. This will allow the code to be updated a bit easier in the future. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | tracing: Remove filter allocator helperSteven Rostedt (VMware)2018-03-10
| | | | | | | | | | | | | | | | | | | | | The __alloc_filter() function does nothing more that allocate the filter. There's no reason to have it as a helper function. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | tracing: Use trace_seq instead of open code string appendingSteven Rostedt (VMware)2018-03-10
| | | | | | | | | | | | | | | | | | | | | The filter code does open code string appending to produce an error message. Instead it can be simplified by using trace_seq function helpers. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | tracing: Remove BUG_ON() from append_filter_string()Steven Rostedt (VMware)2018-03-10
| | | | | | | | | | | | | | | | | | | | | There's no reason to BUG if there's a bug in the filtering code. Simply do a warning and return. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | tracing: Add inter-event blurb to HIST_TRIGGERS config optionTom Zanussi2018-03-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | So that users know that inter-event tracing is supported as part of the HIST_TRIGGERS option, include text to that effect in the help text. Link: http://lkml.kernel.org/r/a38e24231d8d980be636b56d35814570acfd167a.1516069914.git.tom.zanussi@linux.intel.com Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | tracing: Use the ring-buffer nesting to allow synthetic events to be tracedSteven Rostedt (VMware)2018-03-10
| | | | | | | | | | | | | | | | | | | | | | | | Synthetic events can be done within the recording of other events. Notify the ring buffer via ring_buffer_nest_start() and ring_buffer_nest_end() that this is intended and not to block it due to its recursion protection. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | ring-buffer: Add nesting for adding events within eventsSteven Rostedt (VMware)2018-03-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The ring-buffer code has recusion protection in case tracing ends up tracing itself, the ring-buffer will detect that it was called at the same context (normal, softirq, interrupt or NMI), and not continue to record the event. With the histogram synthetic events, they are called while tracing another event at the same context. The recusion protection triggers because it detects tracing at the same context and stops it. Add ring_buffer_nest_start() and ring_buffer_nest_end() that will notify the ring buffer that a trace is about to happen within another trace and that it is intended, and not to trigger the recursion blocking. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | tracing: Add a clock attribute for hist triggersTom Zanussi2018-03-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The default clock if timestamps are used in a histogram is "global". If timestamps aren't used, the clock is irrelevant. Use the "clock=" param only if you want to override the default "global" clock for a histogram with timestamps. Link: http://lkml.kernel.org/r/427bed1389c5d22aa40c3e0683e30cc3d151e260.1516069914.git.tom.zanussi@linux.intel.com Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Rajvi Jingar <rajvi.jingar@intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | tracing: Make tracing_set_clock() non-staticTom Zanussi2018-03-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Allow tracing code outside of trace.c to access tracing_set_clock(). Some applications may require a particular clock in order to function properly, such as latency calculations. Also, add an accessor returning the current clock string. Link: http://lkml.kernel.org/r/6d1c53e9ee2163f54e1849f5376573f54f0e6009.1516069914.git.tom.zanussi@linux.intel.com Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | tracing: Add 'last error' error facility for hist triggersTom Zanussi2018-03-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With the addition of variables and actions, it's become necessary to provide more detailed error information to users about syntax errors. Add a 'last error' facility accessible via the erroring event's 'hist' file. Reading the hist file after an error will display more detailed information about what went wrong, if information is available. This extended error information will be available until the next hist trigger command for that event. # echo xxx > /sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger echo: write error: Invalid argument # cat /sys/kernel/debug/tracing/events/sched/sched_wakeup/hist ERROR: Couldn't yyy: zzz Last command: xxx Also add specific error messages for variable and action errors. Link: http://lkml.kernel.org/r/64e9c422fc8aeafcc2f7a3b4328c0cffe7969129.1516069914.git.tom.zanussi@linux.intel.com Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | tracing: Add hist trigger support for variable reference aliasesTom Zanussi2018-03-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add support for alias=$somevar where alias can be used as onmatch.xxx($alias). Aliases are a way of creating a new name for an existing variable, for flexibly in making naming more clear in certain cases. For example in the below the user perhaps feels that using $new_lat in the synthetic event invocation is opaque or doesn't fit well stylistically with previous triggers, so creates an alias of $new_lat named $latency and uses that in the call instead: # echo 'hist:keys=next_pid:new_lat=common_timestamp.usecs' > /sys/kernel/debug/tracing/events/sched/sched_switch/trigger # echo 'hist:keys=pid:latency=$new_lat: onmatch(sched.sched_switch).wake2($latency,pid)' > /sys/kernel/debug/tracing/events/synthetic/wake1/trigger Link: http://lkml.kernel.org/r/ef20a65d921af3a873a6f1e8c71407c926d5586f.1516069914.git.tom.zanussi@linux.intel.com Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | tracing: Add cpu field for hist triggersTom Zanussi2018-03-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A common key to use in a histogram is the cpuid - add a new cpu 'synthetic' field named 'cpu' for that purpose. Link: http://lkml.kernel.org/r/89537645bfc957e0d76e2cacf5f0ada88691a6cc.1516069914.git.tom.zanussi@linux.intel.com Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | tracing: Allow whitespace to surround hist trigger filterTom Zanussi2018-03-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The existing code only allows for one space before and after the 'if' specifying the filter for a hist trigger. Add code to make that more permissive as far as whitespace goes. Specifically, we want to allow spaces in the trigger itself now that we have additional syntax (onmatch/onmax) where spaces are more natural e.g. spaces after commas in param lists. Link: http://lkml.kernel.org/r/1053090c3c308d4f431accdeb59dff4b511d4554.1516069914.git.tom.zanussi@linux.intel.com Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | tracing: Add 'onmax' hist trigger action supportTom Zanussi2018-03-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add an 'onmax(var).save(field,...)' hist trigger action which is invoked whenever an event exceeds the current maximum. The end result is that the trace event fields or variables specified as the onmax.save() params will be saved if 'var' exceeds the current maximum for that hist trigger entry. This allows context from the event that exhibited the new maximum to be saved for later reference. When the histogram is displayed, additional fields displaying the saved values will be printed. As an example the below defines a couple of hist triggers, one for sched_wakeup and another for sched_switch, keyed on pid. Whenever a sched_wakeup occurs, the timestamp is saved in the entry corresponding to the current pid, and when the scheduler switches back to that pid, the timestamp difference is calculated. If the resulting latency exceeds the current maximum latency, the specified save() values are saved: # echo 'hist:keys=pid:ts0=common_timestamp.usecs \ if comm=="cyclictest"' >> \ /sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger # echo 'hist:keys=next_pid:\ wakeup_lat=common_timestamp.usecs-$ts0:\ onmax($wakeup_lat).save(next_comm,prev_pid,prev_prio,prev_comm) \ if next_comm=="cyclictest"' >> \ /sys/kernel/debug/tracing/events/sched/sched_switch/trigger When the histogram is displayed, the max value and the saved values corresponding to the max are displayed following the rest of the fields: # cat /sys/kernel/debug/tracing/events/sched/sched_switch/hist { next_pid: 3728 } hitcount: 199 \ max: 123 next_comm: cyclictest prev_pid: 0 \ prev_prio: 120 prev_comm: swapper/3 { next_pid: 3730 } hitcount: 1321 \ max: 15 next_comm: cyclictest prev_pid: 0 \ prev_prio: 120 prev_comm: swapper/1 { next_pid: 3729 } hitcount: 1973\ max: 25 next_comm: cyclictest prev_pid: 0 \ prev_prio: 120 prev_comm: swapper/0 Totals: Hits: 3493 Entries: 3 Dropped: 0 Link: http://lkml.kernel.org/r/006907f71b1e839bb059337ec3c496f84fcb71de.1516069914.git.tom.zanussi@linux.intel.com Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | tracing: Add 'onmatch' hist trigger action supportTom Zanussi2018-03-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add an 'onmatch(matching.event).<synthetic_event_name>(param list)' hist trigger action which is invoked with the set of variables or event fields named in the 'param list'. The result is the generation of a synthetic event that consists of the values contained in those variables and/or fields at the time the invoking event was hit. As an example the below defines a simple synthetic event using a variable defined on the sched_wakeup_new event, and shows the event definition with unresolved fields, since the sched_wakeup_new event with the testpid variable hasn't been defined yet: # echo 'wakeup_new_test pid_t pid; int prio' >> \ /sys/kernel/debug/tracing/synthetic_events # cat /sys/kernel/debug/tracing/synthetic_events wakeup_new_test pid_t pid; int prio The following hist trigger both defines a testpid variable and specifies an onmatch() trace action that uses that variable along with a non-variable field to generate a wakeup_new_test synthetic event whenever a sched_wakeup_new event occurs, which because of the 'if comm == "cyclictest"' filter only happens when the executable is cyclictest: # echo 'hist:testpid=pid:keys=$testpid:\ onmatch(sched.sched_wakeup_new).wakeup_new_test($testpid, prio) \ if comm=="cyclictest"' >> \ /sys/kernel/debug/tracing/events/sched/sched_wakeup_new/trigger Creating and displaying a histogram based on those events is now just a matter of using the fields and new synthetic event in the tracing/events/synthetic directory, as usual: # echo 'hist:keys=pid,prio:sort=pid,prio' >> \ /sys/kernel/debug/tracing/events/synthetic/wakeup_new_test/trigger Link: http://lkml.kernel.org/r/8c2a574bcb7530c876629c901ecd23911b14afe8.1516069914.git.tom.zanussi@linux.intel.com Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Rajvi Jingar <rajvi.jingar@intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | tracing: Add support for 'field variables'Tom Zanussi2018-03-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Users should be able to directly specify event fields in hist trigger 'actions' rather than being forced to explicitly create a variable for that purpose. Add support allowing fields to be used directly in actions, which essentially does just that - creates 'invisible' variables for each bare field specified in an action. If a bare field refers to a field on another (matching) event, it even creates a special histogram for the purpose (since variables can't be defined on an existing histogram after histogram creation). Here's a simple example that demonstrates both. Basically the onmatch() action creates a list of variables corresponding to the parameters of the synthetic event to be generated, and then uses those values to generate the event. So for the wakeup_latency synthetic event 'call' below the first param, $wakeup_lat, is a variable defined explicitly on sched_switch, where 'next_pid' is just a normal field on sched_switch, and prio is a normal field on sched_waking. Since the mechanism works on variables, those two normal fields just have 'invisible' variables created internally for them. In the case of 'prio', which is on another event, we actually need to create an additional hist trigger and define the invisible variable on that, since once a hist trigger is defined, variables can't be added to it later. echo 'wakeup_latency u64 lat; pid_t pid; int prio' >> /sys/kernel/debug/tracing/synthetic_events echo 'hist:keys=pid:ts0=common_timestamp.usecs >> /sys/kernel/debug/tracing/events/sched/sched_waking/trigger echo 'hist:keys=next_pid:wakeup_lat=common_timestamp.usecs-$ts0: onmatch(sched.sched_waking).wakeup_latency($wakeup_lat,next_pid,prio) >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger Link: http://lkml.kernel.org/r/8e8dcdac1ea180ed7a3689e1caeeccede9dc42b3.1516069914.git.tom.zanussi@linux.intel.com Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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