There might be systems where MAP_32BIT is not defined, like some some
RHEL7 powerpc versions.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Kyle McMartin <kyle@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Fixes: 256763b017 ("perf trace beauty mmap: Add more conditional defines")
Link: http://lkml.kernel.org/r/1481831814-23683-1-git-send-email-jolsa@kernel.org
[ Changed the Fixme cset to the one removing the conditional switch case for MAP_32BIT ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
While testing Joe's conversion of samples/bpf/ to use tools/lib/bpf/ I noticed
some warnings building samples/bpf/ on a Fedora Rawhide container, with
clang/llvm 3.9 I noticed this:
[root@1e797fdfbf4f linux]# make -j4 O=/tmp/build/linux/ samples/bpf/
make[1]: Entering directory '/tmp/build/linux'
CHK include/config/kernel.release
GEN ./Makefile
CHK include/generated/uapi/linux/version.h
Using /git/linux as source for kernel
<SNIP>
HOSTCC samples/bpf/trace_output_user.o
/git/linux/samples/bpf/trace_output_user.c:64:6: warning: no previous
prototype for 'perf_event_read' [-Wmissing-prototypes]
void perf_event_read(print_fn fn)
^~~~~~~~~~~~~~~
HOSTLD samples/bpf/trace_output
make[1]: Leaving directory '/tmp/build/linux'
Shut up the compiler by making that function static.
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Joe Stringer <joe@ovn.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20161215152927.GC6866@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Switch all of the sample code to use the function names from
tools/lib/bpf so that they're consistent with that, and to declare their
own log buffers. This allow the next commit to be purely devoted to
getting rid of the duplicate library in samples/bpf.
Committer notes:
Testing it:
On a fedora rawhide container, with clang/llvm 3.9, sharing the host
linux kernel git tree:
# make O=/tmp/build/linux/ headers_install
# make O=/tmp/build/linux -C samples/bpf/
Since I forgot to make it privileged, just tested it outside the
container, using what it generated:
# uname -a
Linux jouet 4.9.0-rc8+ #1 SMP Mon Dec 12 11:20:49 BRT 2016 x86_64 x86_64 x86_64 GNU/Linux
# cd /var/lib/docker/devicemapper/mnt/c43e09a53ff56c86a07baf79847f00e2cc2a17a1e2220e1adbf8cbc62734feda/rootfs/tmp/build/linux/samples/bpf/
# ls -la offwaketime
-rwxr-xr-x. 1 root root 24200 Dec 15 12:19 offwaketime
# file offwaketime
offwaketime: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, for GNU/Linux 2.6.32, BuildID[sha1]=c940d3f127d5e66cdd680e42d885cb0b64f8a0e4, not stripped
# readelf -SW offwaketime_kern.o | grep PROGBITS
[ 2] .text PROGBITS 0000000000000000 000040 000000 00 AX 0 0 4
[ 3] kprobe/try_to_wake_up PROGBITS 0000000000000000 000040 0000d8 00 AX 0 0 8
[ 5] tracepoint/sched/sched_switch PROGBITS 0000000000000000 000118 000318 00 AX 0 0 8
[ 7] maps PROGBITS 0000000000000000 000430 000050 00 WA 0 0 4
[ 8] license PROGBITS 0000000000000000 000480 000004 00 WA 0 0 1
[ 9] version PROGBITS 0000000000000000 000484 000004 00 WA 0 0 4
# ./offwaketime | head -5
swapper/1;start_secondary;cpu_startup_entry;schedule_preempt_disabled;schedule;__schedule;-;---;; 106
CPU 0/KVM;entry_SYSCALL_64_fastpath;sys_ioctl;do_vfs_ioctl;kvm_vcpu_ioctl;kvm_arch_vcpu_ioctl_run;kvm_vcpu_block;schedule;__schedule;-;try_to_wake_up;swake_up_locked;swake_up;apic_timer_expired;apic_timer_fn;__hrtimer_run_queues;hrtimer_interrupt;local_apic_timer_interrupt;smp_apic_timer_interrupt;__irqentry_text_start;cpuidle_enter;call_cpuidle;cpu_startup_entry;start_secondary;;swapper/3 2
Compositor;entry_SYSCALL_64_fastpath;sys_futex;do_futex;futex_wait;futex_wait_queue_me;schedule;__schedule;-;try_to_wake_up;futex_requeue;do_futex;sys_futex;entry_SYSCALL_64_fastpath;;SoftwareVsyncTh 5
firefox;entry_SYSCALL_64_fastpath;sys_poll;do_sys_poll;poll_schedule_timeout;schedule_hrtimeout_range;schedule_hrtimeout_range_clock;schedule;__schedule;-;try_to_wake_up;pollwake;__wake_up_common;__wake_up_sync_key;pipe_write;__vfs_write;vfs_write;sys_write;entry_SYSCALL_64_fastpath;;Timer 13
JS Helper;entry_SYSCALL_64_fastpath;sys_futex;do_futex;futex_wait;futex_wait_queue_me;schedule;__schedule;-;try_to_wake_up;do_futex;sys_futex;entry_SYSCALL_64_fastpath;;firefox 2
#
Signed-off-by: Joe Stringer <joe@ovn.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: netdev@vger.kernel.org
Link: http://lkml.kernel.org/r/20161214224342.12858-2-joe@ovn.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Commit 6c90598174 ("bpf: pre-allocate hash map elements") introduces
map_flags to bpf_attr for BPF_MAP_CREATE command. Expose this new
parameter in libbpf.
By exposing it, users can access flags such as whether or not to
preallocate the map.
Signed-off-by: Joe Stringer <joe@ovn.org>
Acked-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Link: http://lkml.kernel.org/r/20161209024620.31660-4-joe@ovn.org
[ Added clarifying comment made by Wang Nan ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fixes the following issue when building without access to 'u32' type:
./tools/lib/bpf/bpf.h:27:23: error: unknown type name ‘u32’
Signed-off-by: Joe Stringer <joe@ovn.org>
Acked-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Link: http://lkml.kernel.org/r/20161209024620.31660-3-joe@ovn.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The tools version of this header is out of date; update it to the latest
version from the kernel headers.
Signed-off-by: Joe Stringer <joe@ovn.org>
Acked-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Link: http://lkml.kernel.org/r/20161209024620.31660-2-joe@ovn.org
[ Sync it harder, after merging with what was in net-next via perf/urgent via torvalds/master to get BPG_PROG_(AT|DE)TACH, etc ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
If jump target is outside of function range, perf is not handling it
correctly. Especially when target address is lesser than function start
address, target offset will be negative. But, target address declared to
be unsigned, converts negative number into 2's complement. See below
example. Here target of 'jumpq' instruction at 34cf8 is 34ac0 which is
lesser than function start address(34cf0).
34ac0 - 34cf0 = -0x230 = 0xfffffffffffffdd0
Objdump output:
0000000000034cf0 <__sigaction>:
__GI___sigaction():
34cf0: lea -0x20(%rdi),%eax
34cf3: cmp -bashx1,%eax
34cf6: jbe 34d00 <__sigaction+0x10>
34cf8: jmpq 34ac0 <__GI___libc_sigaction>
34cfd: nopl (%rax)
34d00: mov 0x386161(%rip),%rax # 3bae68 <_DYNAMIC+0x2e8>
34d07: movl -bashx16,%fs:(%rax)
34d0e: mov -bashxffffffff,%eax
34d13: retq
perf annotate before applying patch:
__GI___sigaction /usr/lib64/libc-2.22.so
lea -0x20(%rdi),%eax
cmp -bashx1,%eax
v jbe 10
v jmpq fffffffffffffdd0
nop
10: mov _DYNAMIC+0x2e8,%rax
movl -bashx16,%fs:(%rax)
mov -bashxffffffff,%eax
retq
perf annotate after applying patch:
__GI___sigaction /usr/lib64/libc-2.22.so
lea -0x20(%rdi),%eax
cmp -bashx1,%eax
v jbe 10
^ jmpq 34ac0 <__GI___libc_sigaction>
nop
10: mov _DYNAMIC+0x2e8,%rax
movl -bashx16,%fs:(%rax)
mov -bashxffffffff,%eax
retq
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Chris Riyder <chris.ryder@arm.com>
Cc: Kim Phillips <kim.phillips@arm.com>
Cc: Markus Trippelsdorf <markus@trippelsdorf.de>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Taeung Song <treeze.taeung@gmail.com>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/1480953407-7605-3-git-send-email-ravi.bangoria@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Architectures like PowerPC have jump instructions that includes a target
address as a second operand. For example, 'bne cr7,0xc0000000000f6154'.
Add support for such instruction in perf annotate.
objdump o/p:
c0000000000f6140: ld r9,1032(r31)
c0000000000f6144: cmpdi cr7,r9,0
c0000000000f6148: bne cr7,0xc0000000000f6154
c0000000000f614c: ld r9,2312(r30)
c0000000000f6150: std r9,1032(r31)
c0000000000f6154: ld r9,88(r31)
Corresponding perf annotate o/p:
Before patch:
ld r9,1032(r31)
cmpdi cr7,r9,0
v bne 3ffffffffff09f2c
ld r9,2312(r30)
std r9,1032(r31)
74: ld r9,88(r31)
After patch:
ld r9,1032(r31)
cmpdi cr7,r9,0
v bne 74
ld r9,2312(r30)
std r9,1032(r31)
74: ld r9,88(r31)
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Chris Riyder <chris.ryder@arm.com>
Cc: Kim Phillips <kim.phillips@arm.com>
Cc: Markus Trippelsdorf <markus@trippelsdorf.de>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Taeung Song <treeze.taeung@gmail.com>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/1480953407-7605-2-git-send-email-ravi.bangoria@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Enable perf_evsel::ignore_missing_thread for -u option to ignore
complete failure if any of the user's processes die between its
enumeration and time we open the event.
Committer notes:
While doing a 'make -j4 allmodconfig' we sometimes get into the race:
Before:
# perf record -u acme
Error:
The sys_perf_event_open() syscall returned with 3 (No such process) for event (cycles:ppp).
/bin/dmesg may provide additional information.
No CONFIG_PERF_EVENTS=y kernel support configured?
#
After:
[root@jouet ~]# perf record -u acme
WARNING: Ignored open failure for pid 9888
WARNING: Ignored open failure for pid 18059
[root@jouet ~]#
Which is an improvement, with the races not preventing the remaining threads
for the specified user from being monitored, but the message probably needs
further clarification.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1481538943-21874-6-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Adding perf_evsel::ignore_missing_cpu_thread bool.
When set true, it allows perf to ignore error of missing pid of perf
event syscall.
We remove missing thread id from the thread_map, so the rest of the
processing like ioctl and mmap won't get disturbed with -1 fd.
The reason for supporting this is to ease up monitoring group of pids,
that 'disappear' before perf opens their event. This currently leads
perf to report error and exit and makes perf record's -u option unusable
under certain setup.
With this change we will allow this race and ignore such failure with
following warning:
WARNING: Ignored open failure for pid 8605
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20161213074622.GA3084@krava
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
It's more readable and will ease up following patches.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1481538943-21874-3-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
I.e. those parameters/functions _are_ used, so ditch that misleading attribute.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-13cqtjh0yojg5gzvpq1zzpl0@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The --idle-hist option is to analyze system idle state so which process
makes cpu to go idle. If this option is specified, non-idle events will
be skipped and processes switching to/from idle will be shown.
This option is mostly useful when used with --summary(-only) option. In
the idle-time summary view, idle time is accounted to previous thread
which is run before idle task.
The example output looks like following:
Idle-time summary
comm parent sched-out idle-time min-idle avg-idle max-idle stddev migrations
(count) (msec) (msec) (msec) (msec) %
--------------------------------------------------------------------------------------------
rcu_preempt[7] 2 95 550.872 0.011 5.798 23.146 7.63 0
migration/1[16] 2 1 15.558 15.558 15.558 15.558 0.00 0
khugepaged[39] 2 1 3.062 3.062 3.062 3.062 0.00 0
kworker/0:1H[124] 2 2 4.728 0.611 2.364 4.116 74.12 0
systemd-journal[167] 1 1 4.510 4.510 4.510 4.510 0.00 0
kworker/u16:3[558] 2 13 74.737 0.080 5.749 12.960 21.96 0
irq/34-iwlwifi[628] 2 21 118.403 0.032 5.638 23.990 24.00 0
kworker/u17:0[673] 2 1 3.523 3.523 3.523 3.523 0.00 0
dbus-daemon[722] 1 1 6.743 6.743 6.743 6.743 0.00 0
ifplugd[741] 1 1 58.826 58.826 58.826 58.826 0.00 0
wpa_supplicant[1490] 1 1 13.302 13.302 13.302 13.302 0.00 0
wpa_actiond[1492] 1 2 4.064 0.168 2.032 3.896 91.72 0
dockerd[1500] 1 1 0.055 0.055 0.055 0.055 0.00 0
...
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: David Ahern <dsahern@gmail.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20161208144755.16673-6-namhyung@kernel.org
Link: http://lkml.kernel.org/r/20161213080632.19099-2-namhyung@kernel.org
[ Merged fix sent by Namhyumg, as posted in the second Link: tag ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Sometimes it only focuses on idle-related events like upcoming idle-hist
feature. In this case we don't want to see other event to reduce noise.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: David Ahern <dsahern@gmail.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20161208144755.16673-5-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
In order to investigate the idleness reason, it is necessary to keep the
callchains when entering idle. This can be identified by the
sched:sched_switch event having the next_pid field as 0.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: David Ahern <dsahern@gmail.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20161208144755.16673-4-namhyung@kernel.org
Link: http://lkml.kernel.org/r/20161213080632.19099-1-namhyung@kernel.org
[ Merged fix from Namhyung, see second Link: tag ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The struct idle_time_data is to keep idle stats with callchains entering
to the idle task. The normal thread_runtime calculation is done
transparently since it extends the struct thread_runtime.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: David Ahern <dsahern@gmail.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20161208144755.16673-3-namhyung@kernel.org
[ Align struct field names ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The is_idle_sample() function actually does more than determining
whether sample come from idle task. Split the callchain part into
save_task_callchain() to make it clearer.
Also checking prev_pid from trace data looks preferred than just
checking sample->pid since it's possible, although rare, to have invalid
0 pid/tid on scheduling an exiting task.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: David Ahern <dsahern@gmail.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20161208144755.16673-2-namhyung@kernel.org
[ Remove some needless () in some return statements ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To make it nicer and easily maintainable.
Also moving the check into fixdep sub make, so its output is not
scattered around the build output.
Removing extra $$ from mman*.h checks.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1481030331-31944-5-git-send-email-jolsa@kernel.org
[ Use /bin/sh, and 'function check() {' -> 'check () {' to make it work with busybox, in Alpine Linux, for instance ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
It's another busy cycle for the docs tree, as the sphinx conversion
continues. Highlights include:
- Further work on PDF output, which remains a bit of a pain but should be
more solid now.
- Five more DocBook template files converted to Sphinx. Only 27 to go...
Lots of plain-text files have also been converted and integrated.
- Images in binary formats have been replaced with more source-friendly
versions.
- Various bits of organizational work, including the renaming of various
files discussed at the kernel summit.
- New documentation for the device_link mechanism.
...and, of course, lots of typo fixes and small updates.
-----BEGIN PGP SIGNATURE-----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=A0EV
-----END PGP SIGNATURE-----
Merge tag 'docs-4.10' of git://git.lwn.net/linux
Pull documentation update from Jonathan Corbet:
"These are the documentation changes for 4.10.
It's another busy cycle for the docs tree, as the sphinx conversion
continues. Highlights include:
- Further work on PDF output, which remains a bit of a pain but
should be more solid now.
- Five more DocBook template files converted to Sphinx. Only 27 to
go... Lots of plain-text files have also been converted and
integrated.
- Images in binary formats have been replaced with more
source-friendly versions.
- Various bits of organizational work, including the renaming of
various files discussed at the kernel summit.
- New documentation for the device_link mechanism.
... and, of course, lots of typo fixes and small updates"
* tag 'docs-4.10' of git://git.lwn.net/linux: (193 commits)
dma-buf: Extract dma-buf.rst
Update Documentation/00-INDEX
docs: 00-INDEX: document directories/files with no docs
docs: 00-INDEX: remove non-existing entries
docs: 00-INDEX: add missing entries for documentation files/dirs
docs: 00-INDEX: consolidate process/ and admin-guide/ description
scripts: add a script to check if Documentation/00-INDEX is sane
Docs: change sh -> awk in REPORTING-BUGS
Documentation/core-api/device_link: Add initial documentation
core-api: remove an unexpected unident
ppc/idle: Add documentation for powersave=off
Doc: Correct typo, "Introdution" => "Introduction"
Documentation/atomic_ops.txt: convert to ReST markup
Documentation/local_ops.txt: convert to ReST markup
Documentation/assoc_array.txt: convert to ReST markup
docs-rst: parse-headers.pl: cleanup the documentation
docs-rst: fix media cleandocs target
docs-rst: media/Makefile: reorganize the rules
docs-rst: media: build SVG from graphviz files
docs-rst: replace bayer.png by a SVG image
...
Merge updates from Andrew Morton:
- various misc bits
- most of MM (quite a lot of MM material is awaiting the merge of
linux-next dependencies)
- kasan
- printk updates
- procfs updates
- MAINTAINERS
- /lib updates
- checkpatch updates
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (123 commits)
init: reduce rootwait polling interval time to 5ms
binfmt_elf: use vmalloc() for allocation of vma_filesz
checkpatch: don't emit unified-diff error for rename-only patches
checkpatch: don't check c99 types like uint8_t under tools
checkpatch: avoid multiple line dereferences
checkpatch: don't check .pl files, improve absolute path commit log test
scripts/checkpatch.pl: fix spelling
checkpatch: don't try to get maintained status when --no-tree is given
lib/ida: document locking requirements a bit better
lib/rbtree.c: fix typo in comment of ____rb_erase_color
lib/Kconfig.debug: make CONFIG_STRICT_DEVMEM depend on CONFIG_DEVMEM
MAINTAINERS: add drm and drm/i915 irc channels
MAINTAINERS: add "C:" for URI for chat where developers hang out
MAINTAINERS: add drm and drm/i915 bug filing info
MAINTAINERS: add "B:" for URI where to file bugs
get_maintainer: look for arbitrary letter prefixes in sections
printk: add Kconfig option to set default console loglevel
printk/sound: handle more message headers
printk/btrfs: handle more message headers
printk/kdb: handle more message headers
...
.c and .h source files should not be executable, change
the permissions to 0644.
[ This would normally go through Andrew Morton, but his ancient
patch-based toolchain doesn't do permission changes ]
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull irq updates from Thomas Gleixner:
"The irq department provides:
- a major update to the auto affinity management code, which is used
by multi-queue devices
- move of the microblaze irq chip driver into the common driver code
so it can be shared between microblaze, powerpc and MIPS
- a series of updates to the ARM GICV3 interrupt controller
- the usual pile of fixes and small improvements all over the place"
* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (25 commits)
powerpc/virtex: Use generic xilinx irqchip driver
irqchip/xilinx: Try to fall back if xlnx,kind-of-intr not provided
irqchip/xilinx: Add support for parent intc
irqchip/xilinx: Rename get_irq to xintc_get_irq
irqchip/xilinx: Restructure and use jump label api
irqchip/xilinx: Clean up print messages
microblaze/irqchip: Move intc driver to irqchip
ARM: virt: Select ARM_GIC_V3_ITS
ARM: gic-v3-its: Add 32bit support to GICv3 ITS
irqchip/gic-v3-its: Specialise readq and writeq accesses
irqchip/gic-v3-its: Specialise flush_dcache operation
irqchip/gic-v3-its: Narrow down Entry Size when used as a divider
irqchip/gic-v3-its: Change unsigned types for AArch32 compatibility
irqchip/gic-v3: Use nops macro for Cavium ThunderX erratum 23154
irqchip/gic-v3: Convert arm64 GIC accessors to {read,write}_sysreg_s
genirq/msi: Drop artificial PCI dependency
irqchip/bcm7038-l1: Implement irq_cpu_offline() callback
genirq/affinity: Use default affinity mask for reserved vectors
genirq/affinity: Take reserved vectors into account when spreading irqs
PCI: Remove the irq_affinity mask from struct pci_dev
...
Pull timer updates from Thomas Gleixner:
"The time/timekeeping/timer folks deliver with this update:
- Fix a reintroduced signed/unsigned issue and cleanup the whole
signed/unsigned mess in the timekeeping core so this wont happen
accidentaly again.
- Add a new trace clock based on boot time
- Prevent injection of random sleep times when PM tracing abuses the
RTC for storage
- Make posix timers configurable for real tiny systems
- Add tracepoints for the alarm timer subsystem so timer based
suspend wakeups can be instrumented
- The usual pile of fixes and updates to core and drivers"
* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
timekeeping: Use mul_u64_u32_shr() instead of open coding it
timekeeping: Get rid of pointless typecasts
timekeeping: Make the conversion call chain consistently unsigned
timekeeping_Force_unsigned_clocksource_to_nanoseconds_conversion
alarmtimer: Add tracepoints for alarm timers
trace: Update documentation for mono, mono_raw and boot clock
trace: Add an option for boot clock as trace clock
timekeeping: Add a fast and NMI safe boot clock
timekeeping/clocksource_cyc2ns: Document intended range limitation
timekeeping: Ignore the bogus sleep time if pm_trace is enabled
selftests/timers: Fix spelling mistake "Asyncrhonous" -> "Asynchronous"
clocksource/drivers/bcm2835_timer: Unmap region obtained by of_iomap
clocksource/drivers/arm_arch_timer: Map frame with of_io_request_and_map()
arm64: dts: rockchip: Arch counter doesn't tick in system suspend
clocksource/drivers/arm_arch_timer: Don't assume clock runs in suspend
posix-timers: Make them configurable
posix_cpu_timers: Move the add_device_randomness() call to a proper place
timer: Move sys_alarm from timer.c to itimer.c
ptp_clock: Allow for it to be optional
Kconfig: Regenerate *.c_shipped files after previous changes
...
Pull smp hotplug updates from Thomas Gleixner:
"This is the final round of converting the notifier mess to the state
machine. The removal of the notifiers and the related infrastructure
will happen around rc1, as there are conversions outstanding in other
trees.
The whole exercise removed about 2000 lines of code in total and in
course of the conversion several dozen bugs got fixed. The new
mechanism allows to test almost every hotplug step standalone, so
usage sites can exercise all transitions extensively.
There is more room for improvement, like integrating all the
pointlessly different architecture mechanisms of synchronizing,
setting cpus online etc into the core code"
* 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (60 commits)
tracing/rb: Init the CPU mask on allocation
soc/fsl/qbman: Convert to hotplug state machine
soc/fsl/qbman: Convert to hotplug state machine
zram: Convert to hotplug state machine
KVM/PPC/Book3S HV: Convert to hotplug state machine
arm64/cpuinfo: Convert to hotplug state machine
arm64/cpuinfo: Make hotplug notifier symmetric
mm/compaction: Convert to hotplug state machine
iommu/vt-d: Convert to hotplug state machine
mm/zswap: Convert pool to hotplug state machine
mm/zswap: Convert dst-mem to hotplug state machine
mm/zsmalloc: Convert to hotplug state machine
mm/vmstat: Convert to hotplug state machine
mm/vmstat: Avoid on each online CPU loops
mm/vmstat: Drop get_online_cpus() from init_cpu_node_state/vmstat_cpu_dead()
tracing/rb: Convert to hotplug state machine
oprofile/nmi timer: Convert to hotplug state machine
net/iucv: Use explicit clean up labels in iucv_init()
x86/pci/amd-bus: Convert to hotplug state machine
x86/oprofile/nmi: Convert to hotplug state machine
...
For several devices, the rootwait time is sensitive because it directly
affects booting time. The polling interval of rootwait is currently
100ms. To save unnessesary waiting time, reduce the polling interval to
5 ms.
[akpm@linux-foundation.org: remove used-once #define]
Link: http://lkml.kernel.org/r/20161207060743.1728-1-js07.lee@samsung.com
Signed-off-by: Jungseung Lee <js07.lee@samsung.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We have observed page allocations failures of order 4 during core dump
while trying to allocate vma_filesz. This results in a useless core
file of size 0. To improve reliability use vmalloc().
Note that the vmalloc() allocation is bounded by sysctl_max_map_count,
which is 65,530 by default. So with a 4k page size, and 8 bytes per
seg, this is a max of 128 pages or an order 7 allocation. Other parts
of the core dump path, such as fill_files_note() are already using
vmalloc() for presumably similar reasons.
Link: http://lkml.kernel.org/r/1479745791-17611-1-git-send-email-jbaron@akamai.com
Signed-off-by: Jason Baron <jbaron@akamai.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I generated a patch with `git format-patch` which checkpatch thinks is
invalid:
$ ./scripts/checkpatch.pl lpc-dt/0006-mfd-dt-Move-syscon-bindings-to-syscon-subdirectory.patch
WARNING: added, moved or deleted file(s), does MAINTAINERS need updating?
Documentation/devicetree/bindings/mfd/{ => syscon}/aspeed-scu.txt | 0
ERROR: Does not appear to be a unified-diff format patch
total: 1 errors, 1 warnings, 0 lines checked
NOTE: For some of the reported defects, checkpatch may be able to
mechanically convert to the typical style using --fix or --fix-inplace.
lpc-dt/0006-mfd-dt-Move-syscon-bindings-to-syscon-subdirectory.patch has style problems, please review.
NOTE: If any of the errors are false positives, please report
them to the maintainer, see CHECKPATCH in MAINTAINERS.
The patch in question was all renames with no edits, giving 100%
similarity and thus no diff markers.
Set '$is_patch = 1;' in the add/remove/rename detection to avoid
generating spurious warnings.
Link: http://lkml.kernel.org/r/20161205232224.22685-1-andrew@aj.id.au
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Acked-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Tools contains user space code so uintX_t types are just fine.
Link: http://lkml.kernel.org/r/1479286379-853-1-git-send-email-tomas.winkler@intel.com
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Acked-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Code that puts a single dereferencing identifier on multiple lines like:
struct_identifier->member[index].
member = <foo>;
is generally hard to follow.
Prefer that dereferencing identifiers be single line.
Link: http://lkml.kernel.org/r/e9c191ae3f41bedc8ffd5c0fbcc5a1cec1d1d2df.1478120869.git.joe@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
perl files (*.pl) are mostly inappropriate to check coding styles so
exempt them from long line checks and various .[ch] file type tests.
And as well, only scan absolute paths in the commit log, not in the
patch.
Link: http://lkml.kernel.org/r/85b101d50acafe6c0261d9f7df283c827da52c4a.1477340110.git.joe@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fixes the following warning:
Use of uninitialized value $root in concatenation (.) or string at /path/to/checkpatch.pl line 764.
Link: http://lkml.kernel.org/r/1476719709-16668-1-git-send-email-jerome.forissier@linaro.org
Signed-off-by: Jerome Forissier <jerome.forissier@linaro.org>
Reviewed-by: Brian Norris <computersforpeace@gmail.com>
Acked-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I wanted to wrap a bunch of ida_simple_get calls into their own locking,
until I dug around and read the original commit message. Stuff like
this should imo be added to the kernel doc, let's do that.
Link: http://lkml.kernel.org/r/20161027072216.20411-1-daniel.vetter@ffwll.ch
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In Case 3 of `sibling == parent->rb_right':
Right rotation will not change color of sl and S in the diagram
(i.e. should not change "sl" to "Sl", "S" to "s")
In Case 3 of `sibling == parent->rb_left':
(p) (p)
/ \ / \
S N --> sr N
/ \ /
Sl sr S
/
Sl
This is actually left rotation at "S", not right rotation.
In Case 4 of `sibling == parent->rb_left':
(p) (s)
/ \ / \
S N --> Sl P
/ \ / \
sl (sr) (sr) N
This is actually right rotation at "(p)" + color flips, not left
rotation + color flips.
Link: http://lkml.kernel.org/r/1472391115-3702-1-git-send-email-fykcee1@gmail.com
Signed-off-by: Jie Chen <fykcee1@gmail.com>
Cc: Wei Yang <weiyang@linux.vnet.ibm.com>
Cc: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
With CONFIG_DEVMEM not set, CONFIG_STRICT_DEVMEM will be useless even if
it is set =y, thus let's update the dependency in Kconfig.
Link: http://lkml.kernel.org/r/20161006051217.GA31027@dhcp-128-65.nay.redhat.com
Signed-off-by: Dave Young <dyoung@redhat.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1476966135-26943-4-git-send-email-jani.nikula@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Dave Airlie <airlied@gmail.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Make it easier to find the developer chat for the subsystem or driver.
Link: http://lkml.kernel.org/r/1476966135-26943-3-git-send-email-jani.nikula@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Dave Airlie <airlied@gmail.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1476966135-26943-2-git-send-email-jani.nikula@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Dave Airlie <airlied@gmail.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Different subsystems and drivers have different preferences for where to
file bugs and what information to include. Add "B:" entry for
specifying the URI for the bug tracker directly, a web page for detailed
info on filing bugs, or a mailto: URI.
Link: http://lkml.kernel.org/r/1476966135-26943-1-git-send-email-jani.nikula@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jani Nikula proposes patches to add a few new letter prefixes for "B:"
bug reporting and "C:" maintainer chatting to the various sections of
MAINTAINERS.
Add a generic mechanism to get_maintainer.pl to find sections that have
any combination of "[A-Z]" letter prefix types in a section.
Link: http://lkml.kernel.org/r/1477332323.1984.8.camel@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Dave Airlie <airlied@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add a configuration option to set the default console loglevel. This
is, as before, still possible to override at runtime through bootargs
(loglevel=<x>), sysrq and /proc/printk.
There are cases where adding additional arguments on the commandline is
impractical, and changing the default for the kernel when being built
makes more sense. Provide such a method here, for those who choose to
do so.
Also, while touching this code, clarify the difference between
MESSAGE_LOGLEVEL_DEFAULT and CONSOLE_LOGLEVEL_DEFAULT.
Link: http://lkml.kernel.org/r/1479676829-30031-1-git-send-email-olof@lixom.net
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 4bcc595ccd ("printk: reinstate KERN_CONT for printing
continuation lines") allows to define more message headers for a single
message. The motivation is that continuous lines might get mixed.
Therefore it make sense to define the right log level for every piece of
a cont line.
This patch allows to copy only the real message level. We should ignore
KERN_CONT because <filename:line> is added for each message. By other
words, we want to know where each piece of the line comes from.
[pmladek@suse.com: fix a check of the valid message level]
Link: http://lkml.kernel.org/r/20161111183444.GE2145@dhcp128.suse.cz
Link: http://lkml.kernel.org/r/1478695291-12169-5-git-send-email-pmladek@suse.com
Signed-off-by: Petr Mladek <pmladek@suse.com>
Cc: Joe Perches <joe@perches.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Takashi Iwai <tiwai@suse.com>
Cc: Chris Mason <clm@fb.com>
Cc: Josef Bacik <jbacik@fb.com>
Cc: David Sterba <dsterba@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 4bcc595ccd ("printk: reinstate KERN_CONT for printing
continuation lines") allows to define more message headers for a single
message. The motivation is that continuous lines might get mixed.
Therefore it make sense to define the right log level for every piece of
a cont line.
The current btrfs_printk() macros do not support continuous lines at the
moment. But better be prepared for a custom messages and avoid
potential "lvl" buffer overflow.
This patch iterates over the entire message header. It is interested
only into the message level like the original code.
This patch also introduces PRINTK_MAX_SINGLE_HEADER_LEN. Three bytes
are enough for the message level header at the moment. But it used to
be three, see the commit 04d2c8c83d ("printk: convert the format for
KERN_<LEVEL> to a 2 byte pattern").
Also I fixed the default ratelimit level. It looked very strange when it
was different from the default log level.
[pmladek@suse.com: Fix a check of the valid message level]
Link: http://lkml.kernel.org/r/20161111183236.GD2145@dhcp128.suse.cz
Link: http://lkml.kernel.org/r/1478695291-12169-4-git-send-email-pmladek@suse.com
Signed-off-by: Petr Mladek <pmladek@suse.com>
Acked-by: David Sterba <dsterba@suse.com>
Cc: Joe Perches <joe@perches.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Takashi Iwai <tiwai@suse.com>
Cc: Chris Mason <clm@fb.com>
Cc: Josef Bacik <jbacik@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 4bcc595ccd ("printk: reinstate KERN_CONT for printing
continuation lines") allows to define more message headers for a single
message. The motivation is that continuous lines might get mixed.
Therefore it make sense to define the right log level for every piece of
a cont line.
This patch introduces printk_skip_headers() that will skip all headers
and uses it in the kdb code instead of printk_skip_level().
This approach helps to fix other printk_skip_level() users
independently.
Link: http://lkml.kernel.org/r/1478695291-12169-3-git-send-email-pmladek@suse.com
Signed-off-by: Petr Mladek <pmladek@suse.com>
Cc: Joe Perches <joe@perches.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Takashi Iwai <tiwai@suse.com>
Cc: Chris Mason <clm@fb.com>
Cc: Josef Bacik <jbacik@fb.com>
Cc: David Sterba <dsterba@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 4bcc595ccd ("printk: reinstate KERN_CONT for printing
continuation lines") added back KERN_CONT message header. As a result
it might appear in the middle of the line when the parts are squashed
via the temporary NMI buffer.
A reasonable solution seems to be to split the text in the NNI temporary
not only by newlines but also by the message headers.
Another solution would be to filter out KERN_CONT when writing to the
temporary buffer. But this would complicate the lockless handling.
Also it would not solve problems with a missing newline that was there
even before the KERN_CONT stuff.
This patch moves the temporary buffer handling into separate function.
I played with it and it seems that using the char pointers make the code
easier to read.
Also it prints the final newline as a continuous line.
Finally, it moves handling of the s->len overflow into the paranoid
check. And allows to recover from the disaster.
Link: http://lkml.kernel.org/r/1478695291-12169-2-git-send-email-pmladek@suse.com
Signed-off-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Joe Perches <joe@perches.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Takashi Iwai <tiwai@suse.com>
Cc: Chris Mason <clm@fb.com>
Cc: Josef Bacik <jbacik@fb.com>
Cc: David Sterba <dsterba@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
vsnprintf() adds the trailing '\0' but it does not count it into the
number of printed characters. The result is that there is one byte less
space for the real characters in the buffer.
The broken check for the free space might cause that we will repeatedly
try to print 1 character into the buffer, never reach the full buffer,
and do not count the messages as missed.
Also vsnprintf() returns the number of characters that would be printed
if the buffer was big enough. As a result, s->len might be bigger than
the size of the buffer[*]. And the printk() function might return
bigger len than it really printed. Both problems are fixed by using
vscnprintf() instead.
Note that I though about increasing the number of missed messages even
when the message was shrunken. But it made the code even more
complicated. I think that it is not worth it. Shrunken messages are
usually easy to recognize. And it should be a corner case.
[*] The overflown s->len value is crazy and unexpected. I "made a
mistake" and reported this situation as an internal error when fixed
handling of PR_CONT headers in some other patch.
Link: http://lkml.kernel.org/r/20161208174912.GA17042@linux.suse
Signed-off-by: Petr Mladek <pmladek@suse.com>
CcL Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: Chris Mason <clm@fb.com>
Cc: David Sterba <dsterba@suse.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Josef Bacik <jbacik@fb.com>
Cc: Joe Perches <joe@perches.com>
Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Takashi Iwai <tiwai@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
