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576398 commits

Author SHA1 Message Date
Wang Nan
30372f04c9 perf script: Print bpf-output events in 'perf script'
This patch allows 'perf script' output messages from BPF program.  For
example, use test_bpf_output_3.c at the end of this commit message,

  # ./perf record -e bpf-output/no-inherit,name=evt/ \
                 -e ./test_bpf_output_3.c/map:channel.event=evt/ \
                 usleep 100000

  # ./perf script
          usleep  4882 21384.532523:                       evt:  ffffffff810e97d1 sys_nanosleep ([kernel.kallsyms])
      BPF output: 0000: 52 61 69 73 65 20 61 20  Raise a
                  0008: 42 50 46 20 65 76 65 6e  BPF even
                  0010: 74 21 00 00              t!..
      BPF string: "Raise a BPF event!"

          usleep  4882 21384.632606:                       evt:  ffffffff8105c609 kretprobe_trampoline_holder ([kernel.kallsyms
      BPF output: 0000: 52 61 69 73 65 20 61 20  Raise a
                  0008: 42 50 46 20 65 76 65 6e  BPF even
                  0010: 74 21 00 00              t!..
      BPF string: "Raise a BPF event!"

Two samples from BPF output are printed by both binary and string
format.

If BPF program output something unprintable, string format is
suppressed.

  /************************ BEGIN **************************/
  #include <uapi/linux/bpf.h>
  struct bpf_map_def {
         unsigned int type;
         unsigned int key_size;
         unsigned int value_size;
         unsigned int max_entries;
  };
  #define SEC(NAME) __attribute__((section(NAME), used))
  static u64 (*ktime_get_ns)(void) =
         (void *)BPF_FUNC_ktime_get_ns;
  static int (*trace_printk)(const char *fmt, int fmt_size, ...) =
         (void *)BPF_FUNC_trace_printk;
  static int (*get_smp_processor_id)(void) =
         (void *)BPF_FUNC_get_smp_processor_id;
  static int (*perf_event_output)(void *, struct bpf_map_def *, int, void *, unsigned long) =
         (void *)BPF_FUNC_perf_event_output;

  struct bpf_map_def SEC("maps") channel = {
         .type = BPF_MAP_TYPE_PERF_EVENT_ARRAY,
         .key_size = sizeof(int),
         .value_size = sizeof(u32),
         .max_entries = __NR_CPUS__,
  };

  static inline int __attribute__((always_inline))
  func(void *ctx, int type)
  {
         char output_str[] = "Raise a BPF event!";

         perf_event_output(ctx, &channel, get_smp_processor_id(),
                           &output_str, sizeof(output_str));
         return 0;
  }
  SEC("func_begin=sys_nanosleep")
  int func_begin(void *ctx) {return func(ctx, 1);}
  SEC("func_end=sys_nanosleep%return")
  int func_end(void *ctx) { return func(ctx, 2);}
  char _license[] SEC("license") = "GPL";
  int _version SEC("version") = LINUX_VERSION_CODE;
  /************************* END ***************************/

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1456312845-111583-3-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-02-24 12:09:24 -03:00
Wang Nan
c339b1a90e perf tools: Make binary data printer code in trace_event public available
Move code printing binray data from trace_event() to utils.c and allows
passing different printer. Further commits will use this logic to print
bpf output event.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1456312845-111583-2-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-02-24 11:38:01 -03:00
Steven Rostedt (Red Hat)
d045437a16 tracing: Fix showing function event in available_events
The ftrace:function event is only displayed for parsing the function tracer
data. It is not used to enable function tracing, and does not include an
"enable" file in its event directory.

Originally, this event was kept separate from other events because it did
not have a ->reg parameter. But perf added a "reg" parameter for its use
which caused issues, because it made the event available to functions where
it was not compatible for.

Commit 9b63776fa3 "tracing: Do not enable function event with enable"
added a TRACE_EVENT_FL_IGNORE_ENABLE flag that prevented the function event
from being enabled by normal trace events. But this commit missed keeping
the function event from being displayed by the "available_events" directory,
which is used to show what events can be enabled by set_event.

One documented way to enable all events is to:

 cat available_events > set_event

But because the function event is displayed in the available_events, this
now causes an INVALID error:

 cat: write error: Invalid argument

Reported-by: Chunyu Hu <chuhu@redhat.com>
Fixes: 9b63776fa3 "tracing: Do not enable function event with enable"
Cc: stable@vger.kernel.org # 3.4+
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-02-24 09:17:11 -05:00
Christian Borntraeger
d7444794a0 KVM: async_pf: do not warn on page allocation failures
In async_pf we try to allocate with NOWAIT to get an element quickly
or fail. This code also handle failures gracefully. Lets silence
potential page allocation failures under load.

qemu-system-s39: page allocation failure: order:0,mode:0x2200000
[...]
Call Trace:
([<00000000001146b8>] show_trace+0xf8/0x148)
[<000000000011476a>] show_stack+0x62/0xe8
[<00000000004a36b8>] dump_stack+0x70/0x98
[<0000000000272c3a>] warn_alloc_failed+0xd2/0x148
[<000000000027709e>] __alloc_pages_nodemask+0x94e/0xb38
[<00000000002cd36a>] new_slab+0x382/0x400
[<00000000002cf7ac>] ___slab_alloc.constprop.30+0x2dc/0x378
[<00000000002d03d0>] kmem_cache_alloc+0x160/0x1d0
[<0000000000133db4>] kvm_setup_async_pf+0x6c/0x198
[<000000000013dee8>] kvm_arch_vcpu_ioctl_run+0xd48/0xd58
[<000000000012fcaa>] kvm_vcpu_ioctl+0x372/0x690
[<00000000002f66f6>] do_vfs_ioctl+0x3be/0x510
[<00000000002f68ec>] SyS_ioctl+0xa4/0xb8
[<0000000000781c5e>] system_call+0xd6/0x264
[<000003ffa24fa06a>] 0x3ffa24fa06a

Cc: stable@vger.kernel.org
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-24 14:47:46 +01:00
Paolo Bonzini
0c1d77f4ba KVM: x86: fix conversion of addresses to linear in 32-bit protected mode
Commit e8dd2d2d64 ("Silence compiler warning in arch/x86/kvm/emulate.c",
2015-09-06) broke boot of the Hurd.  The bug is that the "default:"
case actually could modify "la", but after the patch this change is
not reflected in *linear.

The bug is visible whenever a non-zero segment base causes the linear
address to wrap around the 4GB mark.

Fixes: e8dd2d2d64
Cc: stable@vger.kernel.org
Reported-by: Aurelien Jarno <aurelien@aurel32.net>
Tested-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-24 14:47:45 +01:00
Paolo Bonzini
172b2386ed KVM: x86: fix missed hardware breakpoints
Sometimes when setting a breakpoint a process doesn't stop on it.
This is because the debug registers are not loaded correctly on
VCPU load.

The following simple reproducer from Oleg Nesterov tries using debug
registers in two threads.  To see the bug, run a 2-VCPU guest with
"taskset -c 0" and run "./bp 0 1" inside the guest.

    #include <unistd.h>
    #include <signal.h>
    #include <stdlib.h>
    #include <stdio.h>
    #include <sys/wait.h>
    #include <sys/ptrace.h>
    #include <sys/user.h>
    #include <asm/debugreg.h>
    #include <assert.h>

    #define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)

    unsigned long encode_dr7(int drnum, int enable, unsigned int type, unsigned int len)
    {
        unsigned long dr7;

        dr7 = ((len | type) & 0xf)
            << (DR_CONTROL_SHIFT + drnum * DR_CONTROL_SIZE);
        if (enable)
            dr7 |= (DR_GLOBAL_ENABLE << (drnum * DR_ENABLE_SIZE));

        return dr7;
    }

    int write_dr(int pid, int dr, unsigned long val)
    {
        return ptrace(PTRACE_POKEUSER, pid,
                offsetof (struct user, u_debugreg[dr]),
                val);
    }

    void set_bp(pid_t pid, void *addr)
    {
        unsigned long dr7;
        assert(write_dr(pid, 0, (long)addr) == 0);
        dr7 = encode_dr7(0, 1, DR_RW_EXECUTE, DR_LEN_1);
        assert(write_dr(pid, 7, dr7) == 0);
    }

    void *get_rip(int pid)
    {
        return (void*)ptrace(PTRACE_PEEKUSER, pid,
                offsetof(struct user, regs.rip), 0);
    }

    void test(int nr)
    {
        void *bp_addr = &&label + nr, *bp_hit;
        int pid;

        printf("test bp %d\n", nr);
        assert(nr < 16); // see 16 asm nops below

        pid = fork();
        if (!pid) {
            assert(ptrace(PTRACE_TRACEME, 0,0,0) == 0);
            kill(getpid(), SIGSTOP);
            for (;;) {
                label: asm (
                    "nop; nop; nop; nop;"
                    "nop; nop; nop; nop;"
                    "nop; nop; nop; nop;"
                    "nop; nop; nop; nop;"
                );
            }
        }

        assert(pid == wait(NULL));
        set_bp(pid, bp_addr);

        for (;;) {
            assert(ptrace(PTRACE_CONT, pid, 0, 0) == 0);
            assert(pid == wait(NULL));

            bp_hit = get_rip(pid);
            if (bp_hit != bp_addr)
                fprintf(stderr, "ERR!! hit wrong bp %ld != %d\n",
                    bp_hit - &&label, nr);
        }
    }

    int main(int argc, const char *argv[])
    {
        while (--argc) {
            int nr = atoi(*++argv);
            if (!fork())
                test(nr);
        }

        while (wait(NULL) > 0)
            ;
        return 0;
    }

Cc: stable@vger.kernel.org
Suggested-by: Nadav Amit <namit@cs.technion.ac.il>
Reported-by: Andrey Wagin <avagin@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-24 14:47:39 +01:00
Jiri Olsa
c19ac91245 perf script: Display data_src values
Adding support to display data_src values, for events with data_src data
in sample.

Example:
  $ perf script
  ...
           rcuos/3    32 [002] ... 68501042 Local RAM hit|SNP None or Hit|TLB L1 or L2 hit|LCK No   ...
           rcuos/3    32 [002] ... 68100142 L1 hit|SNP None|TLB L1 or L2 hit|LCK No                 ...
           swapper     0 [002] ... 68100242 LFB hit|SNP None|TLB L1 or L2 hit|LCK No                ...
           swapper     0 [000] ... 68100142 L1 hit|SNP None|TLB L1 or L2 hit|LCK No                 ...
           swapper     0 [000] ... 50100142 L1 hit|SNP None|TLB L2 miss|LCK No                      ...
           rcuos/3    32 [002] ... 68100142 L1 hit|SNP None|TLB L1 or L2 hit|LCK No                 ...
   plugin-containe 16538 [000] ... 6a100142 L1 hit|SNP None|TLB L1 or L2 hit|LCK Yes                ...
           gkrellm  1736 [000] ... 68100242 LFB hit|SNP None|TLB L1 or L2 hit|LCK No                ...
           gkrellm  1736 [000] ... 6a100142 L1 hit|SNP None|TLB L1 or L2 hit|LCK Yes                ...

                                   ^^^^^^^^ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
                             data_src value                     data_src translation

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1456303616-26926-14-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-02-24 10:32:11 -03:00
Jiri Olsa
8b0819c8a3 perf tools: Change perf_mem__lck_scnprintf to return nb of displayed bytes
Moving strncat call into scnprintf to easily track number of displayed
bytes. It will be used in following patch.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1456303616-26926-13-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-02-24 10:31:03 -03:00
Jiri Olsa
149d750767 perf tools: Change perf_mem__snp_scnprintf to return nb of displayed bytes
Moving strncat/strcpy calls into scnprintf to easily track number of
displayed bytes. It will be used in following patch.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1456303616-26926-12-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-02-24 10:30:22 -03:00
Jiri Olsa
969075630e perf tools: Change perf_mem__lvl_scnprintf to return nb of displayed bytes
Moving strncat/strcpy calls into scnprintf to easily track number of
displayed bytes. It will be used in following patch.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1456303616-26926-11-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-02-24 10:30:14 -03:00
Jiri Olsa
b1a5fbea3d perf tools: Change perf_mem__tlb_scnprintf to return nb of displayed bytes
Moving strncat/strcpy calls into scnprintf to easily track
number of displayed bytes. It will be used in following patch.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1456303616-26926-10-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-02-24 10:30:03 -03:00
Jiri Olsa
69a7727592 perf tools: Introduce perf_mem__lck_scnprintf function
Move meminfo's lck display function into mem-events.c object, so it
could be reused later from script code.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1456303616-26926-9-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-02-24 10:29:52 -03:00
Jiri Olsa
2c07af13dc perf tools: Introduce perf_mem__snp_scnprintf function
Move meminfo's snp display function into mem-events.c object, so it
could be reused later from script code.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1456303616-26926-8-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-02-24 10:20:45 -03:00
Jiri Olsa
071e9a1e12 perf tools: Introduce perf_mem__lvl_scnprintf function
Move meminfo's lvl display function into mem-events.c object, so it
could be reused later from script code.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1456303616-26926-7-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-02-24 10:20:28 -03:00
Jiri Olsa
0c877d759d perf tools: Introduce perf_mem__tlb_scnprintf function
Move meminfo's tlb display function into mem-events.c object, so it
could be reused later from script code.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1456303616-26926-6-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-02-24 10:20:08 -03:00
Jiri Olsa
2ba7ac5814 perf mem: Introduce perf_mem_events__name function
Wrap perf_mem_events[].name into perf_mem_events__name() so we could alter the
events name if needed.

This will be handy when changing latency settings for loads event in following
patch.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1456303616-26926-3-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-02-24 10:11:52 -03:00
Jiri Olsa
54fbad54eb perf mem record: Check for memory events support
Check if current kernel support available memory events and display the
status within -e  list option:

  $ perf mem record -e list
  ldlat-loads  : available
  ldlat-stores : available

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1456303616-26926-2-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-02-24 10:10:59 -03:00
Rafael J. Wysocki
e249714571 Revert "ACPI, PCI, irq: remove interrupt count restriction"
Revert commit b5bd026954 (ACPI, PCI, irq: remove interrupt count
restriction) that introduced a boot regression on some systems
where it caused kmalloc() to be used too early.

Link: http://marc.info/?l=linux-acpi&m=145580159209240&w=2
Reported-by: Nalla, Ravikanth <ravikanth.nalla@hpe.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-02-24 13:55:38 +01:00
Rafael J. Wysocki
5ec5d10682 Revert "ACPI / PCI: Simplify acpi_penalize_isa_irq()"
Revert commit 0971686954 "ACPI / PCI: Simplify acpi_penalize_isa_irq()"
that depends on commit b5bd026954 (ACPI, PCI, irq: remove interrupt
count restriction) which introduced a regression and needs to be
reverted for this reason.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-02-24 13:53:46 +01:00
Marc Zyngier
1d6a821277 arm/arm64: KVM: Feed initialized memory to MMIO accesses
On an MMIO access, we always copy the on-stack buffer info
the shared "run" structure, even if this is a read access.
This ends up leaking up to 8 bytes of uninitialized memory
into userspace, depending on the size of the access.

An obvious fix for this one is to only perform the copy if
this is an actual write.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-24 11:53:09 +00:00
Valentin Rothberg
9ef2d8be55 arc: SMP: CONFIG_ARC_IPI_DBG cleanup
Previous Commit ("ARC: SMP: No need for CONFIG_ARC_IPI_DBG") removed
the Kconfig option ARC_IPI_DBG.  Remove the last reference on this
option.

Signed-off-by: Valentin Rothberg <valentinrothberg@gmail.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-02-24 14:15:39 +05:30
Carlo Caione
79318452cb MAINTAINERS: Extend info, add wiki and ml for meson arch
Update the maintainers info with wiki and mailing list for the meson
platform. Fix a wrong file attribution and add maintainership for the
generic meson platforms.

Signed-off-by: Carlo Caione <carlo@endlessm.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
2016-02-24 00:11:12 -08:00
Olof Johansson
9fa6c2b1aa Two omap fixes for omaps against v4.5-rc5:
- Yet another fix for n900 onenand to avoid corruption. This time to
   fix the issue of mounting onenand back and forth between the original
   maemo kernel and mainline Linux kernel. And it also seems there will
   be two more fixes coming via the MTD tree as issues were discovered
   also in the onenand driver during testing.
 
 - Revert tps65217 regulator clean up as it breaks MMC for am335x
   variants. The proper way to clean this up is just to rename the
   tps65217.dtsi file into tps65217-am335x.dtsi as a similar setup
   is used on many am335x boards.
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Merge tag 'omap-for-v4.5/fixes-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into fixes

Two omap fixes for omaps against v4.5-rc5:

- Yet another fix for n900 onenand to avoid corruption. This time to
  fix the issue of mounting onenand back and forth between the original
  maemo kernel and mainline Linux kernel. And it also seems there will
  be two more fixes coming via the MTD tree as issues were discovered
  also in the onenand driver during testing.

- Revert tps65217 regulator clean up as it breaks MMC for am335x
  variants. The proper way to clean this up is just to rename the
  tps65217.dtsi file into tps65217-am335x.dtsi as a similar setup
  is used on many am335x boards.

* tag 'omap-for-v4.5/fixes-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap:
  ARM: OMAP2+: Fix onenand initialization to avoid filesystem corruption
  Revert "regulator: tps65217: remove tps65217.dtsi file"

Signed-off-by: Olof Johansson <olof@lixom.net>
2016-02-24 00:10:11 -08:00
Stafford Horne
f4bcfa1da6 sched/wait: Fix wait_event_freezable() documentation
I noticed the comment label 'wait_event' was wrong.

Signed-off-by: Stafford Horne <shorne@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1456234768-24933-1-git-send-email-shorne@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-24 09:09:45 +01:00
Antoine Tenart
a9e5547b19 MAINTAINERS: alpine: add a new maintainer and update the entry
Add myself as a co-maintainer for the Alpine support. Also update the
entry to take in account Alpine ARM64 boards, Alpine ARM device trees
and Alpine-specific drivers.

Signed-off-by: Antoine Tenart <antoine.tenart@free-electrons.com>
Acked-by: Tsahee Zidenberg <tsahee@annapurnalabs.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
2016-02-24 00:09:12 -08:00
Ludovic Desroches
5e45a2589d ARM: at91/dt: fix typo in sama5d2 pinmux descriptions
PIN_PA15 macro has the same value as PIN_PA14 so we were overriding PA14
mux/configuration.

Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Reported-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
Fixes: 7f16cb676c ("ARM: at91/dt: add sama5d2 pinmux")
Cc: <stable@vger.kernel.org> # v4.4+
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
2016-02-24 00:08:19 -08:00
Olof Johansson
b223c9f593 The i.MX fixes for v4.5:
- Drop the bogus interrupt-parent from i.MX6 CAAM node, which leads to
    the CAAM IRQs not getting unmasked at the GPC level.
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Merge tag 'imx-fixes-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/shawnguo/linux into fixes

The i.MX fixes for v4.5:
 - Drop the bogus interrupt-parent from i.MX6 CAAM node, which leads to
   the CAAM IRQs not getting unmasked at the GPC level.

* tag 'imx-fixes-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/shawnguo/linux:
  ARM: dts: imx6: remove bogus interrupt-parent from CAAM node

Signed-off-by: Olof Johansson <olof@lixom.net>
2016-02-24 00:05:58 -08:00
Olof Johansson
e3acd74f92 Few fixes for omaps against v4.5-rc3:
- Improve omap_device error message to tell driver writers what is
   wrong after commit 5de85b9d57 ("PM / runtime: Re-init runtime PM
   states at probe error and driver unbind"). There will be also a
   handful of driver related fixes also queued separately. But adding
   this error message makes it easy to fix any omap_device using
   drivers suffering from this issue so I think it's important to
   have.
 
 - Also related to commit 5de85b9d57 discussion, let's fix a bug
   where disabling PM runtime via sysfs will also cause the hardware
   state to be different from PM runtime state.
 
 - Fix audio clocks for beagle-x15.
 
 - Use wakeup-source instead of gpio-key,wakeup for the new entries
   that sneaked in during the merge window.
 
 - Fix a legacy booting vs device tree based booting regression for
   n900 where the legacy user space expects to have the device
   revision available in /proc/atags also when booted with device
   tree.
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Merge tag 'omap-for-v4.5/fixes-rc3-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into fixes

Few fixes for omaps against v4.5-rc3:

- Improve omap_device error message to tell driver writers what is
  wrong after commit 5de85b9d57 ("PM / runtime: Re-init runtime PM
  states at probe error and driver unbind"). There will be also a
  handful of driver related fixes also queued separately. But adding
  this error message makes it easy to fix any omap_device using
  drivers suffering from this issue so I think it's important to
  have.

- Also related to commit 5de85b9d57 discussion, let's fix a bug
  where disabling PM runtime via sysfs will also cause the hardware
  state to be different from PM runtime state.

- Fix audio clocks for beagle-x15.

- Use wakeup-source instead of gpio-key,wakeup for the new entries
  that sneaked in during the merge window.

- Fix a legacy booting vs device tree based booting regression for
  n900 where the legacy user space expects to have the device
  revision available in /proc/atags also when booted with device
  tree.

* tag 'omap-for-v4.5/fixes-rc3-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap:
  ARM: OMAP2+: Fix omap_device for module reload on PM runtime forbid
  ARM: OMAP2+: Improve omap_device error for driver writers
  ARM: DTS: am57xx-beagle-x15: Select SYS_CLK2 for audio clocks
  ARM: dts: am335x/am57xx: replace gpio-key,wakeup with wakeup-source property
  ARM: OMAP2+: Set system_rev from ATAGS for n900

Signed-off-by: Olof Johansson <olof@lixom.net>
2016-02-24 00:05:11 -08:00
Olof Johansson
74a46ec6fb Merge tag 'mvebu-fixes-4.5-2' of git://git.infradead.org/linux-mvebu into fixes
mvebu fixes for 4.5 (part 2)

- Fix the missing mtd flash on linkstation lswtgl
- Use unique machine name for the kirkwood ds112 (for Debian flash-kernel tool)

* tag 'mvebu-fixes-4.5-2' of git://git.infradead.org/linux-mvebu:
  ARM: dts: orion5x: fix the missing mtd flash on linkstation lswtgl
  ARM: dts: kirkwood: use unique machine name for ds112

Signed-off-by: Olof Johansson <olof@lixom.net>
2016-02-24 00:04:59 -08:00
Adam Buchbinder
6a6256f9e0 x86: Fix misspellings in comments
Signed-off-by: Adam Buchbinder <adam.buchbinder@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: trivial@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-24 08:44:58 +01:00
Andy Lutomirski
04d1d281dc x86/entry/32: Add an ASM_CLAC to entry_SYSENTER_32
Both before and after 5f310f739b ("x86/entry/32: Re-implement
SYSENTER using the new C path"), we relied on a uaccess very early
in the SYSENTER path to clear AC.  After that change, though, we can
potentially make it all the way into C code with AC set, which
enlarges the attack surface for SMAP bypass by doing SYSENTER with
AC set.

Strengthen the SMAP protection by addding the missing ASM_CLAC right
at the beginning.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/3e36be110724896e32a4a1fe73bacb349d3cba94.1456262295.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-24 08:43:04 +01:00
Ingo Molnar
c2b8d8c55c perf/core improvements and fixes:
User visible:
 
 - Don't stop PMU parsing on alias parse error, allowing the
   addition of new sysfs PMU files without breaking old tools (Andi Kleen)
 
 - Implement '%' operation in libtraceevent (Daniel Bristot de Oliveira)
 
 - Allow specifying events via -e in 'perf mem record', also listing what events
   can be specified via 'perf mem record -e list' (Jiri Olsa)
 
 - Improve support to 'data_src', 'weight' and 'addr' fields in
   'perf script' (Jiri Olsa)
 
 Infrastructure:
 
 - Export cacheline routines (Jiri Olsa)
 
 - Remove strbuf_{remove,splice}(), dead code (Arnaldo Carvalho de Melo)
 
 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-core-for-mingo-2' 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:

New features:

  - Add API to set values of map entries in a BPF object, be it
    individual map slots or ranges (Wang Nan)

  - Introduce support for the 'bpf-output' event (Wang Nan)

  - Add glue to read perf events in a BPF program (Wang Nan)

User visible changes:

  - Don't stop PMU parsing on alias parse error, allowing the
    addition of new sysfs PMU files without breaking old tools (Andi Kleen)

  - Implement '%' operation in libtraceevent (Daniel Bristot de Oliveira)

  - Allow specifying events via -e in 'perf mem record', also listing what events
    can be specified via 'perf mem record -e list' (Jiri Olsa)

  - Improve support to 'data_src', 'weight' and 'addr' fields in
    'perf script' (Jiri Olsa)

Infrastructure changes:

  - Export cacheline routines (Jiri Olsa)

  - Remove strbuf_{remove,splice}(), dead code (Arnaldo Carvalho de Melo)

Fixes:

  - Sort key fixes: Alignment for srcline, file, trace; fix
    segfault for dynamic, trace events related sort keys (Namyung Kim)

Build fixes:

  - Remove duplicate typedef config_term_func_t definition,
    fixing the build on older systems (Arnaldo Carvalho de Melo)

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-24 08:20:30 +01:00
Vineet Gupta
d73b73f562 ARC: SMP: No need for CONFIG_ARC_IPI_DBG
This was more relevant during SMP bringup.

The warning for bogus msg better be visible always.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-02-24 11:07:32 +05:30
Vineet Gupta
3dea30ca5b ARCv2: Elide sending new cross core intr if receiver didn't ack prev
ARConnect/MCIP IPI sending has a retry-wait loop in case caller had
not seen a previous such interrupt. Turns out that it is not needed at
all. Linux cross core calling allows coalescing multiple IPIs to same
receiver - it is fine as long as there is one.

This logic is built into upper layer already, at a higher level of
abstraction. ipi_send_msg_one() sets the actual msg payload, but it only
calls MCIP IPI sending if msg holder was empty (using
atomic-set-new-and-get-old construct). Thus it is unlikely that the
retry-wait looping was ever getting exercised at all.

Cc: Chuck Jordan <cjordan@synopsys.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-02-24 11:07:31 +05:30
Vineet Gupta
9681787930 ARCv2: SMP: Push IPI_IRQ into IPI provider
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-02-24 11:07:31 +05:30
Vineet Gupta
dbcbc7e7ce ARC: [intc-compact] Remove IPI setup from ARCompact port
There is no real ARC700 based SMP SoC so remove IPI definition.
EZChip's SMP ARC700 is going to use a different intc and IPI provider
anyways.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-02-24 11:07:31 +05:30
Vineet Gupta
bb143f814e ARCv2: SMP: Emulate IPI to self using software triggered interrupt
ARConnect/MCIP Inter-Core-Interrupt module can't send interrupt to
local core. So use core intc capability to trigger software
interrupt to self, using an unsued IRQ #21.

This showed up as csd deadlock with LTP trace_sched on a dual core
system. This test acts as scheduler fuzzer, triggering all sorts of
schedulting activity. Trouble starts with IPI to self, which doesn't get
delivered (effectively lost due to H/w capability), but the msg intended
to be sent remain enqueued in per-cpu @ipi_data.

All subsequent IPIs to this core from other cores get elided due to the
IPI coalescing optimization in ipi_send_msg_one() where a pending msg
implies an IPI already sent and assumes other core is yet to ack it.
After the elided IPI, other core simply goes into csd_lock_wait()
but never comes out as this core never sees the interrupt.

Fixes STAR 9001008624

Cc: Peter Zijlstra <peterz@infradead.org>
Cc: <stable@vger.kernel.org>        [4.2]
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-02-24 11:07:28 +05:30
Andreas Irestål
7c139db2e5 ASoC: adau17x1: Fix incorrect BCLK ratio definitions
Signed-off-by: Andreas Irestål <andire@axis.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-02-24 13:12:10 +09:00
Paul E. McKenney
4f2a848c56 rcu: Export rcu_gp_is_normal()
This commit exports rcu_gp_is_normal() in order to allow it to be used
by rcutorture and rcuperf.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2016-02-23 20:04:51 -08:00
Yang Shi
3500efae44 rcu: Remove rcu_user_hooks_switch
Because there are neither uses nor intended uses for the
rcu_user_hooks_switch() function that was orginally intended
for nohz use, this commit removes it.

Signed-off-by: Yang Shi <yang.shi@linaro.org>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2016-02-23 19:59:56 -08:00
Paul E. McKenney
4b455dc3e1 rcu: Catch up rcu_report_qs_rdp() comment with reality
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2016-02-23 19:59:56 -08:00
Paul E. McKenney
9de630c4f2 rcu: Document unique-name limitation for DEFINE_STATIC_SRCU()
SRCU uses per-CPU variables, and DEFINE_STATIC_SRCU() uses a static
per-CPU variable.  However, per-CPU variables have significant
restrictions, for example, names of per-CPU variables must be globally
unique, even if declared static.  These restrictions carry over to
DEFINE_STATIC_SRCU(), and this commit therefore documents these
restrictions.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Suggested-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Tejun Heo <tj@kernel.org>
2016-02-23 19:59:55 -08:00
Paul Gortmaker
9fc9204ef9 rcu: Make rcu/tiny_plugin.h explicitly non-modular
The Kconfig currently controlling compilation of this code is:

init/Kconfig:config TINY_RCU
init/Kconfig:   bool

...meaning that it currently is not being built as a module by anyone.

Lets remove the modular code that is essentially orphaned, so that
when reading the code there is no doubt it is builtin-only.

Since module_init translates to device_initcall in the non-modular
case, the init ordering remains unchanged with this commit.  We could
consider moving this to an earlier initcall (subsys?) if desired.

We also delete the MODULE_LICENSE tag etc. since all that information
is already contained at the top of the file in the comments.

Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2016-02-23 19:59:55 -08:00
Boqun Feng
b354286eff irq: Privatize irq_common_data::state_use_accessors
irq_common_data::state_use_accessors is not designed for public use.
Therefore make it private so that people who write code accessing it
directly will get blamed by sparse. Also #undef the macro
__irqd_to_state after used in header files, so that the macro can't be
misused.

Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2016-02-23 19:59:54 -08:00
Boqun Feng
67c583a7de RCU: Privatize rcu_node::lock
In patch:

"rcu: Add transitivity to remaining rcu_node ->lock acquisitions"

All locking operations on rcu_node::lock are replaced with the wrappers
because of the need of transitivity, which indicates we should never
write code using LOCK primitives alone(i.e. without a proper barrier
following) on rcu_node::lock outside those wrappers. We could detect
this kind of misuses on rcu_node::lock in the future by adding __private
modifier on rcu_node::lock.

To privatize rcu_node::lock, unlock wrappers are also needed. Replacing
spinlock unlocks with these wrappers not only privatizes rcu_node::lock
but also makes it easier to figure out critical sections of rcu_node.

This patch adds __private modifier to rcu_node::lock and makes every
access to it wrapped by ACCESS_PRIVATE(). Besides, unlock wrappers are
added and raw_spin_unlock(&rnp->lock) and its friends are replaced with
those wrappers.

Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2016-02-23 19:59:54 -08:00
Boqun Feng
ad315455d3 sparse: Add __private to privatize members of structs
In C programming language, we don't have a easy way to privatize a
member of a structure. However in kernel, sometimes there is a need to
privatize a member in case of potential bugs or misuses.

Fortunately, the noderef attribute of sparse is a way to privatize a
member, as by defining a member as noderef, the address-of operator on
the member will produce a noderef pointer to that member, and if anyone
wants to dereference that kind of pointers to read or modify the member,
sparse will yell.

Based on this, __private modifier and related operation ACCESS_PRIVATE()
are introduced, which could help detect undesigned public uses of
private members of structs. Here is an example of sparse's output if it
detect an undersigned public use:

| kernel/rcu/tree.c:4453:25: warning: incorrect type in argument 1 (different modifiers)
| kernel/rcu/tree.c:4453:25:    expected struct raw_spinlock [usertype] *lock
| kernel/rcu/tree.c:4453:25:    got struct raw_spinlock [noderef] *<noident>

Also, this patch improves compiler.h a little bit by adding comments for
"#else" and "#endif".

Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2016-02-23 19:59:53 -08:00
Chen Gang
1914aab543 rcu: Remove useless rcu_data_p when !PREEMPT_RCU
The related warning from gcc 6.0:

  In file included from kernel/rcu/tree.c:4630:0:
  kernel/rcu/tree_plugin.h:810:40: warning: ‘rcu_data_p’ defined but not used [-Wunused-const-variable]
   static struct rcu_data __percpu *const rcu_data_p = &rcu_sched_data;
                                          ^~~~~~~~~~

Also remove always redundant rcu_data_p in tree.c.

Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2016-02-23 19:59:53 -08:00
Paul E. McKenney
aa5a898876 rcutorture: Correct no-expedite console messages
The "Disabled dynamic grace-period expediting" console message is
currently printed unconditionally.  This commit causes it to be
output only when it is impossible to switch between normal and
expedited grace periods, which was the original intent.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2016-02-23 19:59:52 -08:00
Paul E. McKenney
23a9bacd35 rcu: Set rdp->gpwrap when CPU is idle
Commit #e3663b1024 ("rcu: Handle gpnum/completed wrap while dyntick
idle") sets rdp->gpwrap on the wrong side of the "if" statement in
dyntick_save_progress_counter(), that is, it sets it when the CPU is
not idle instead of when it is idle.  Of course, if the CPU is not idle,
its rdp->gpnum won't be lagging beind the global rsp->gpnum, which means
that rdp->gpwrap will never be set.

This commit therefore moves this code to the proper leg of that "if"
statement.  This change means that the "else" cause is just "return 0"
and the "then" clause ends with "return 1", so also move the "return 0"
to follow the "if", dropping the "else" clause.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2016-02-23 19:59:52 -08:00
Paul E. McKenney
4914950aaa rcu: Stop treating in-kernel CPU-bound workloads as errors
Commit 4a81e8328d ("Reduce overhead of cond_resched() checks for RCU")
handles the error case where a nohz_full loops indefinitely in the kernel
with the scheduling-clock interrupt disabled.  However, this handling
includes IPIing the CPU running the offending loop, which is not what
we want for real-time workloads.  And there are starting to be real-time
CPU-bound in-kernel workloads, and these must be handled without IPIing
the CPU, at least not in the common case.  Therefore, this situation can
no longer be dismissed as an error case.

This commit therefore splits the handling out, so that the setting of
bits in the per-CPU rcu_sched_qs_mask variable is done relatively early,
but if the problem persists, resched_cpu() is eventually used to IPI the
CPU containing the offending loop.  Assuming that in-kernel CPU-bound
loops used by real-time tasks contain frequent calls cond_resched_rcu_qs()
(as in more than once per few tens of milliseconds), the real-time tasks
will never be IPIed.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
2016-02-23 19:59:51 -08:00