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Ingo Molnar 39b656ee9f perf/core improvements and fixes: 
perf trace:
 
   Arnaldo Carvalho de Melo:
 
   - Reuse the strace-like syscall_arg_fmt->scnprintf() beautification routines
     (convert integer arguments into strings, like open flags, etc) in tracepoint
     arguments.
 
     For now the type based scnprintf routines (pid_t, umode_t, etc) and the
     ones based in well known arg name based ("fd", etc) gets associated with
     tracepoint args of that type.
 
     A tracepoint only arg, "msr", for the msr:{write,read}_msr gets added as
     an initial step.
 
   - Introduce syscall_arg_fmt->strtoul() methods to be the reverse operation
     of ->scnprintf(), i.e. to go from a string to an integer.
 
   - Implement --filter, just like in 'perf record', that affects the tracepoint
     events specied thus far in the command line, use the ->strtoul() methods
     to allow strings in tables associated with beautifiers to the integers
     the in-kernel tracepoint (eBPF later) filters expect, e.g.:
 
      # perf trace --max-events 1 -e sched:*ipi --filter="cpu==1 || cpu==2"
       0.000 as/24630 sched:sched_wake_idle_without_ipi(cpu: 1)
      #
 
      # perf trace --max-events 1 --max-stack=32 -e msr:* --filter="msr==IA32_TSC_DEADLINE"
       207.000 cc1/19963 msr:write_msr(msr: IA32_TSC_DEADLINE, val: 5442316760822)
                                         do_trace_write_msr ([kernel.kallsyms])
                                         do_trace_write_msr ([kernel.kallsyms])
                                         lapic_next_deadline ([kernel.kallsyms])
                                         clockevents_program_event ([kernel.kallsyms])
                                         hrtimer_interrupt ([kernel.kallsyms])
                                         smp_apic_timer_interrupt ([kernel.kallsyms])
                                         apic_timer_interrupt ([kernel.kallsyms])
                                         [0x6ff66c] (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                         [0x7047c3] (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                         [0x707708] (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                         execute_one_pass (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                         [0x4f3d37] (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                         [0x4f3d49] (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                         execute_pass_list (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                         cgraph_node::expand (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                         [0x2625b4] (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                         symbol_table::finalize_compilation_unit (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                         [0x5ae8b9] (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                         toplev::main (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                         main (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                         [0x26b6a] (/usr/lib/x86_64-linux-gnu/libc-2.29.so)
      #
      # perf trace --max-events 8 -e msr:* --filter="msr==IA32_SPEC_CTRL"
          0.000 :13281/13281 msr:write_msr(msr: IA32_SPEC_CTRL, val: 6)
          0.063 migration/3/25 msr:write_msr(msr: IA32_SPEC_CTRL)
          0.217 kworker/u16:1-/4826 msr:write_msr(msr: IA32_SPEC_CTRL)
          0.687 rcu_sched/11 msr:write_msr(msr: IA32_SPEC_CTRL)
          0.696 :13280/13280 msr:write_msr(msr: IA32_SPEC_CTRL, val: 6)
          0.305 :13281/13281 msr:write_msr(msr: IA32_SPEC_CTRL, val: 6)
          0.355 :13274/13274 msr:write_msr(msr: IA32_SPEC_CTRL, val: 6)
          2.743 kworker/u16:0-/6711 msr:write_msr(msr: IA32_SPEC_CTRL)
      #
      # perf trace --max-events 8 --cpu 1 -e msr:* --filter="msr!=IA32_SPEC_CTRL && msr!=IA32_TSC_DEADLINE && msr != FS_BASE"
            0.000 mtr-packet/30819 msr:write_msr(msr: 0x830, val: 68719479037)
            0.096 :0/0 msr:read_msr(msr: IA32_TSC_ADJUST)
          238.925 mtr-packet/30819 msr:write_msr(msr: 0x830, val: 8589936893)
          511.010 :0/0 msr:write_msr(msr: 0x830, val: 68719479037)
         1005.052 :0/0 msr:read_msr(msr: IA32_TSC_ADJUST)
         1235.131 CPU 0/KVM/3750 msr:write_msr(msr: 0x830, val: 4294969595)
         1235.195 CPU 0/KVM/3750 msr:read_msr(msr: IA32_SYSENTER_ESP, val: -2199023037952)
         1235.201 CPU 0/KVM/3750 msr:read_msr(msr: IA32_APICBASE, val: 4276096000)
      #
 
   - Default to not using libtraceevent and its plugins for beautifying
     tracepoint arguments, since now we're reusing the strace-like beatufiers.
     Use --libtraceevent_print (using just --libtrace is unambiguous and can
     be used as a short hand) to go back to those beautifiers.
 
     This will help in the transition, as can be seen in some of the sched tracepoints
     that still need some work in the libbeauty based mode:
 
     # trace --no-inherit -e msr:*,*sleep,sched:* sleep 1
          0.000 (         ): sched:sched_waking(comm: "trace", pid: 3319 (trace), prio: 120, success: 1)
          0.006 (         ): sched:sched_wakeup(comm: "trace", pid: 3319 (trace), prio: 120, success: 1)
          0.348 (         ): sched:sched_process_exec(filename: 140212596720100, pid: 3319 (sleep), old_pid: 3319 (sleep))
          0.490 (         ): msr:write_msr(msr: FS_BASE, val: 139631189321088)
          0.670 (         ): nanosleep(rqtp: 0x7ffc52c23bc0)                                    ...
          0.674 (         ): sched:sched_stat_runtime(comm: "sleep", pid: 3319 (sleep), runtime: 659259, vruntime: 78942418342)
          0.675 (         ): sched:sched_switch(prev_comm: "sleep", prev_pid: 3319 (sleep), prev_prio: 120, prev_state: 1, next_comm: "swapper/0", next_prio: 120)
       1001.059 (         ): sched:sched_waking(comm: "sleep", pid: 3319 (sleep), prio: 120, success: 1)
       1001.098 (         ): sched:sched_wakeup(comm: "sleep", pid: 3319 (sleep), prio: 120, success: 1)
          0.670 (1000.504 ms):  ... [continued]: nanosleep())                                        = 0
       1001.456 (         ): sched:sched_process_exit(comm: "sleep", pid: 3319 (sleep), prio: 120)
     # trace --libtrace --no-inherit -e msr:*,*sleep,sched:* sleep 1
     # trace --libtrace --no-inherit -e msr:*,*sleep,sched:* sleep 1
          0.000 (         ): sched:sched_waking(comm=trace pid=3323 prio=120 target_cpu=000)
          0.007 (         ): sched:sched_wakeup(comm=trace pid=3323 prio=120 target_cpu=000)
          0.382 (         ): sched:sched_process_exec(filename=/usr/bin/sleep pid=3323 old_pid=3323)
          0.525 (         ): msr:write_msr(c0000100, value 7f5d508a0580)
          0.713 (         ): nanosleep(rqtp: 0x7fff487fb4a0)                                    ...
          0.717 (         ): sched:sched_stat_runtime(comm=sleep pid=3323 runtime=617722 [ns] vruntime=78957731636 [ns])
          0.719 (         ): sched:sched_switch(prev_comm=sleep prev_pid=3323 prev_prio=120 prev_state=S ==> next_comm=swapper/0 next_pid=0 next_prio=120)
       1001.117 (         ): sched:sched_waking(comm=sleep pid=3323 prio=120 target_cpu=000)
       1001.157 (         ): sched:sched_wakeup(comm=sleep pid=3323 prio=120 target_cpu=000)
          0.713 (1000.522 ms):  ... [continued]: nanosleep())                                        = 0
       1001.538 (         ): sched:sched_process_exit(comm=sleep pid=3323 prio=120)
     #
 
   - Make -v (verbose) mode be honoured for .perfconfig based trace.add_events,
     to help in diagnosing problems with building eBPF events (-e source.c).
 
   - When using eBPF syscall payload augmentation do not show strace-like
     syscalls when all the user specified was some tracepoint event, bringing
     the behaviour in line with that of when not using eBPF augmentation.
 
 Intel PT:
 
   exported-sql-viewer GUI:
 
   Adrian Hunter:
 
   - Add LookupModel, HBoxLayout, VBoxLayout, global time range calculations
     so as to add a time chart by CPU.
 
 perf script:
 
   Andi Kleen:
 
   - Allow --time (to specify a time span of interest) with --reltime
 
 perf diff:
 
   Jin Yao:
 
   - Report noise for cycles diff, i.e. a histogram + stddev.
     (timestamps relative to start).
 
 perf annotate:
 
   Arnaldo Carvalho de Melo:
 
   - Initialize env->cpuid when running in live mode (perf top), as it
     is used in some of the per arch annotation init routines.
 
 samples bpf:
 
   Björn Töpel:
 
   - Fixup fallout of using tools/perf/perf-sys. from outside tools/perf.
 
 Core:
 
   Ian Rogers:
 
   - Avoid 'sample_reg_masks' being const + weak, as this breaks with some
     compilers that constant-propagate from the weak symbol.
 
 libperf:
 
   - First part of moving the perf_mmap class from tools/perf to libperf.
 
   - Propagate CFLAGS to libperf from the tools/perf Makefile.
 
 Vendor events:
 
   John Garry:
 
   - Add entry in MAINTAINERS with reviewers for the for perf tool arm64
     pmu-events files.
 
 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-core-for-mingo-5.5-20191011' of 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:

perf trace:

  Arnaldo Carvalho de Melo:

  - Reuse the strace-like syscall_arg_fmt->scnprintf() beautification routines
    (convert integer arguments into strings, like open flags, etc) in tracepoint
    arguments.

    For now the type based scnprintf routines (pid_t, umode_t, etc) and the
    ones based in well known arg name based ("fd", etc) gets associated with
    tracepoint args of that type.

    A tracepoint only arg, "msr", for the msr:{write,read}_msr gets added as
    an initial step.

  - Introduce syscall_arg_fmt->strtoul() methods to be the reverse operation
    of ->scnprintf(), i.e. to go from a string to an integer.

  - Implement --filter, just like in 'perf record', that affects the tracepoint
    events specied thus far in the command line, use the ->strtoul() methods
    to allow strings in tables associated with beautifiers to the integers
    the in-kernel tracepoint (eBPF later) filters expect, e.g.:

     # perf trace --max-events 1 -e sched:*ipi --filter="cpu==1 || cpu==2"
      0.000 as/24630 sched:sched_wake_idle_without_ipi(cpu: 1)
     #

     # perf trace --max-events 1 --max-stack=32 -e msr:* --filter="msr==IA32_TSC_DEADLINE"
      207.000 cc1/19963 msr:write_msr(msr: IA32_TSC_DEADLINE, val: 5442316760822)
                                        do_trace_write_msr ([kernel.kallsyms])
                                        do_trace_write_msr ([kernel.kallsyms])
                                        lapic_next_deadline ([kernel.kallsyms])
                                        clockevents_program_event ([kernel.kallsyms])
                                        hrtimer_interrupt ([kernel.kallsyms])
                                        smp_apic_timer_interrupt ([kernel.kallsyms])
                                        apic_timer_interrupt ([kernel.kallsyms])
                                        [0x6ff66c] (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                        [0x7047c3] (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                        [0x707708] (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                        execute_one_pass (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                        [0x4f3d37] (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                        [0x4f3d49] (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                        execute_pass_list (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                        cgraph_node::expand (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                        [0x2625b4] (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                        symbol_table::finalize_compilation_unit (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                        [0x5ae8b9] (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                        toplev::main (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                        main (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                        [0x26b6a] (/usr/lib/x86_64-linux-gnu/libc-2.29.so)
     #
     # perf trace --max-events 8 -e msr:* --filter="msr==IA32_SPEC_CTRL"
         0.000 :13281/13281 msr:write_msr(msr: IA32_SPEC_CTRL, val: 6)
         0.063 migration/3/25 msr:write_msr(msr: IA32_SPEC_CTRL)
         0.217 kworker/u16:1-/4826 msr:write_msr(msr: IA32_SPEC_CTRL)
         0.687 rcu_sched/11 msr:write_msr(msr: IA32_SPEC_CTRL)
         0.696 :13280/13280 msr:write_msr(msr: IA32_SPEC_CTRL, val: 6)
         0.305 :13281/13281 msr:write_msr(msr: IA32_SPEC_CTRL, val: 6)
         0.355 :13274/13274 msr:write_msr(msr: IA32_SPEC_CTRL, val: 6)
         2.743 kworker/u16:0-/6711 msr:write_msr(msr: IA32_SPEC_CTRL)
     #
     # perf trace --max-events 8 --cpu 1 -e msr:* --filter="msr!=IA32_SPEC_CTRL && msr!=IA32_TSC_DEADLINE && msr != FS_BASE"
           0.000 mtr-packet/30819 msr:write_msr(msr: 0x830, val: 68719479037)
           0.096 :0/0 msr:read_msr(msr: IA32_TSC_ADJUST)
         238.925 mtr-packet/30819 msr:write_msr(msr: 0x830, val: 8589936893)
         511.010 :0/0 msr:write_msr(msr: 0x830, val: 68719479037)
        1005.052 :0/0 msr:read_msr(msr: IA32_TSC_ADJUST)
        1235.131 CPU 0/KVM/3750 msr:write_msr(msr: 0x830, val: 4294969595)
        1235.195 CPU 0/KVM/3750 msr:read_msr(msr: IA32_SYSENTER_ESP, val: -2199023037952)
        1235.201 CPU 0/KVM/3750 msr:read_msr(msr: IA32_APICBASE, val: 4276096000)
     #

  - Default to not using libtraceevent and its plugins for beautifying
    tracepoint arguments, since now we're reusing the strace-like beatufiers.
    Use --libtraceevent_print (using just --libtrace is unambiguous and can
    be used as a short hand) to go back to those beautifiers.

    This will help in the transition, as can be seen in some of the sched tracepoints
    that still need some work in the libbeauty based mode:

    # trace --no-inherit -e msr:*,*sleep,sched:* sleep 1
         0.000 (         ): sched:sched_waking(comm: "trace", pid: 3319 (trace), prio: 120, success: 1)
         0.006 (         ): sched:sched_wakeup(comm: "trace", pid: 3319 (trace), prio: 120, success: 1)
         0.348 (         ): sched:sched_process_exec(filename: 140212596720100, pid: 3319 (sleep), old_pid: 3319 (sleep))
         0.490 (         ): msr:write_msr(msr: FS_BASE, val: 139631189321088)
         0.670 (         ): nanosleep(rqtp: 0x7ffc52c23bc0)                                    ...
         0.674 (         ): sched:sched_stat_runtime(comm: "sleep", pid: 3319 (sleep), runtime: 659259, vruntime: 78942418342)
         0.675 (         ): sched:sched_switch(prev_comm: "sleep", prev_pid: 3319 (sleep), prev_prio: 120, prev_state: 1, next_comm: "swapper/0", next_prio: 120)
      1001.059 (         ): sched:sched_waking(comm: "sleep", pid: 3319 (sleep), prio: 120, success: 1)
      1001.098 (         ): sched:sched_wakeup(comm: "sleep", pid: 3319 (sleep), prio: 120, success: 1)
         0.670 (1000.504 ms):  ... [continued]: nanosleep())                                        = 0
      1001.456 (         ): sched:sched_process_exit(comm: "sleep", pid: 3319 (sleep), prio: 120)
    # trace --libtrace --no-inherit -e msr:*,*sleep,sched:* sleep 1
    # trace --libtrace --no-inherit -e msr:*,*sleep,sched:* sleep 1
         0.000 (         ): sched:sched_waking(comm=trace pid=3323 prio=120 target_cpu=000)
         0.007 (         ): sched:sched_wakeup(comm=trace pid=3323 prio=120 target_cpu=000)
         0.382 (         ): sched:sched_process_exec(filename=/usr/bin/sleep pid=3323 old_pid=3323)
         0.525 (         ): msr:write_msr(c0000100, value 7f5d508a0580)
         0.713 (         ): nanosleep(rqtp: 0x7fff487fb4a0)                                    ...
         0.717 (         ): sched:sched_stat_runtime(comm=sleep pid=3323 runtime=617722 [ns] vruntime=78957731636 [ns])
         0.719 (         ): sched:sched_switch(prev_comm=sleep prev_pid=3323 prev_prio=120 prev_state=S ==> next_comm=swapper/0 next_pid=0 next_prio=120)
      1001.117 (         ): sched:sched_waking(comm=sleep pid=3323 prio=120 target_cpu=000)
      1001.157 (         ): sched:sched_wakeup(comm=sleep pid=3323 prio=120 target_cpu=000)
         0.713 (1000.522 ms):  ... [continued]: nanosleep())                                        = 0
      1001.538 (         ): sched:sched_process_exit(comm=sleep pid=3323 prio=120)
    #

  - Make -v (verbose) mode be honoured for .perfconfig based trace.add_events,
    to help in diagnosing problems with building eBPF events (-e source.c).

  - When using eBPF syscall payload augmentation do not show strace-like
    syscalls when all the user specified was some tracepoint event, bringing
    the behaviour in line with that of when not using eBPF augmentation.

Intel PT:

  exported-sql-viewer GUI:

  Adrian Hunter:

  - Add LookupModel, HBoxLayout, VBoxLayout, global time range calculations
    so as to add a time chart by CPU.

perf script:

  Andi Kleen:

  - Allow --time (to specify a time span of interest) with --reltime

perf diff:

  Jin Yao:

  - Report noise for cycles diff, i.e. a histogram + stddev.
    (timestamps relative to start).

perf annotate:

  Arnaldo Carvalho de Melo:

  - Initialize env->cpuid when running in live mode (perf top), as it
    is used in some of the per arch annotation init routines.

samples bpf:

  Björn Töpel:

  - Fixup fallout of using tools/perf/perf-sys. from outside tools/perf.

Core:

  Ian Rogers:

  - Avoid 'sample_reg_masks' being const + weak, as this breaks with some
    compilers that constant-propagate from the weak symbol.

libperf:

  - First part of moving the perf_mmap class from tools/perf to libperf.

  - Propagate CFLAGS to libperf from the tools/perf Makefile.

Vendor events:

  John Garry:

  - Add entry in MAINTAINERS with reviewers for the for perf tool arm64
    pmu-events files.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-15 07:19:55 +02:00
arch USB fixes for 5.4-rc3 2019-10-12 15:37:12 -07:00
block blk-wbt: fix performance regression in wbt scale_up/scale_down 2019-10-06 09:26:41 -06:00
certs PKCS#7: Refactor verify_pkcs7_signature() 2019-08-05 18:40:18 -04:00
crypto Merge branch 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2019-09-28 08:14:15 -07:00
Documentation hwmon fixes for v5.4-rc3 2019-10-13 08:40:31 -07:00
drivers hwmon fixes for v5.4-rc3 2019-10-13 08:40:31 -07:00
fs A few tracing fixes: 2019-10-13 14:47:10 -07:00
include hwmon fixes for v5.4-rc3 2019-10-13 08:40:31 -07:00
init Merge branch 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2019-09-28 08:14:15 -07:00
ipc ipc/sem.c: convert to use built-in RCU list checking 2019-09-25 17:51:41 -07:00
kernel A few tracing fixes: 2019-10-13 14:47:10 -07:00
lib Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-10-12 14:46:14 -07:00
LICENSES LICENSES: Rename other to deprecated 2019-05-03 06:34:32 -06:00
mm for-linus-20191010 2019-10-11 08:45:32 -07:00
net NFS Client Bugfixes for Linux 5.4-rc3 2019-10-11 14:28:59 -07:00
samples samples/bpf: fix build by setting HAVE_ATTR_TEST to zero 2019-10-07 12:22:18 -03:00
scripts A few tracing fixes: 2019-10-13 14:47:10 -07:00
security selinux/stable-5.4 PR 20191007 2019-10-08 10:51:37 -07:00
sound sound fixes for 5.4-rc1 2019-09-24 16:46:16 -07:00
tools perf/core improvements and fixes: 2019-10-15 07:19:55 +02:00
usr kbuild: update compile-test header list for v5.4-rc2 2019-10-05 15:29:49 +09:00
virt KVM/arm fixes for 5.4, take #1 2019-10-03 12:08:50 +02:00
.clang-format clang-format: Update with the latest for_each macro list 2019-08-31 10:00:51 +02:00
.cocciconfig
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes
.gitignore Modules updates for v5.4 2019-09-22 10:34:46 -07:00
.mailmap Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next 2019-09-18 12:34:53 -07:00
COPYING
CREDITS MAINTAINERS: Remove Simon as Renesas SoC Co-Maintainer 2019-10-10 08:12:51 -07:00
Kbuild kbuild: do not descend to ./Kbuild when cleaning 2019-08-21 21:03:58 +09:00
Kconfig docs: kbuild: convert docs to ReST and rename to *.rst 2019-06-14 14:21:21 -06:00
MAINTAINERS perf/core improvements and fixes: 2019-10-15 07:19:55 +02:00
Makefile Linux 5.4-rc3 2019-10-13 16:37:36 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

README 

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.