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Robert Walker reported a segmentation fault is observed when process
CoreSight trace data; this issue can be easily reproduced by the command
'perf report --itrace=i1000i' for decoding tracing data.
If neither the 'b' flag (synthesize branches events) nor 'l' flag
(synthesize last branch entries) are specified to option '--itrace',
cs_etm_queue::prev_packet will not been initialised. After merging the
code to support exception packets and sample flags, there introduced a
number of uses of cs_etm_queue::prev_packet without checking whether it
is valid, for these cases any accessing to uninitialised prev_packet
will cause crash.
As cs_etm_queue::prev_packet is used more widely now and it's already
hard to follow which functions have been called in a context where the
validity of cs_etm_queue::prev_packet has been checked, this patch
always allocates memory for cs_etm_queue::prev_packet.
Reported-by: Robert Walker <robert.walker@arm.com>
Suggested-by: Robert Walker <robert.walker@arm.com>
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Tested-by: Robert Walker <robert.walker@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Suzuki K Poulouse <suzuki.poulose@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Fixes: 7100b12cf474 ("perf cs-etm: Generate branch sample for exception packet")
Fixes: 24fff5eb2b93 ("perf cs-etm: Avoid stale branch samples when flush packet")
Link: http://lkml.kernel.org/r/20190428083228.20246-1-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Since cs_etm_queue::prev_packet is allocated for all cases, it will
never be NULL pointer; now validity checking prev_packet is pointless,
remove all of them.
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Tested-by: Robert Walker <robert.walker@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Suzuki K Poulouse <suzuki.poulose@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/20190428083228.20246-2-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
An -ENOMEM error is not reported in the GTK GUI. Instead this error
message pops up on the screen:
[root@m35lp76 perf]# ./perf report -i perf.data.error68-1
Processing events... [974K/3M]
Error:failed to process sample
0xf4198 [0x8]: failed to process type: 68
However when I use the same perf.data file with --stdio it works:
[root@m35lp76 perf]# ./perf report -i perf.data.error68-1 --stdio \
| head -12
# Total Lost Samples: 0
#
# Samples: 76K of event 'cycles'
# Event count (approx.): 99056160000
#
# Overhead Command Shared Object Symbol
# ........ ............... ................. .........
#
8.81% find [kernel.kallsyms] [k] ftrace_likely_update
8.74% swapper [kernel.kallsyms] [k] ftrace_likely_update
8.34% sshd [kernel.kallsyms] [k] ftrace_likely_update
2.19% kworker/u512:1- [kernel.kallsyms] [k] ftrace_likely_update
The sample precentage is a bit low.....
The GUI always fails in the FINISHED_ROUND event (68) and does not
indicate the reason why.
When happened is the following. Perf report calls a lot of functions and
down deep when a FINISHED_ROUND event is processed, these functions are
called:
perf_session__process_event()
+ perf_session__process_user_event()
+ process_finished_round()
+ ordered_events__flush()
+ __ordered_events__flush()
+ do_flush()
+ ordered_events__deliver_event()
+ perf_session__deliver_event()
+ machine__deliver_event()
+ perf_evlist__deliver_event()
+ process_sample_event()
+ hist_entry_iter_add() --> only called in GUI case!!!
+ hist_iter__report__callback()
+ symbol__inc_addr_sample()
Now this functions runs out of memory and
returns -ENOMEM. This is reported all the way up
until function
perf_session__process_event() returns to its caller, where -ENOMEM is
changed to -EINVAL and processing stops:
if ((skip = perf_session__process_event(session, event, head)) < 0) {
pr_err("%#" PRIx64 " [%#x]: failed to process type: %d\n",
head, event->header.size, event->header.type);
err = -EINVAL;
goto out_err;
}
This occurred in the FINISHED_ROUND event when it has to process some
10000 entries and ran out of memory.
This patch indicates the root cause and displays it in the status line
of ther perf report GUI.
Output before (on GUI status line):
0xf4198 [0x8]: failed to process type: 68
Output after:
0xf4198 [0x8]: failed to process type: 68 [not enough memory]
Committer notes:
the 'skip' variable needs to be initialized to -EINVAL, so that when the
size is less than sizeof(struct perf_event_attr) we avoid this valid
compiler warning:
util/session.c: In function ‘perf_session__process_events’:
util/session.c:1936:7: error: ‘skip’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
err = skip;
~~~~^~~~~~
util/session.c:1874:6: note: ‘skip’ was declared here
s64 skip;
^~~~
cc1: all warnings being treated as errors
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Reviewed-by: Jiri Olsa <jolsa@redhat.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Link: http://lkml.kernel.org/r/20190423105303.61683-1-tmricht@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
While cross building perf to the ARC architecture on a fedora 30 host,
we were failing with:
CC /tmp/build/perf/bench/numa.o
bench/numa.c: In function ‘worker_thread’:
bench/numa.c:1261:12: error: ‘RUSAGE_THREAD’ undeclared (first use in this function); did you mean ‘SIGEV_THREAD’?
getrusage(RUSAGE_THREAD, &rusage);
^~~~~~~~~~~~~
SIGEV_THREAD
bench/numa.c:1261:12: note: each undeclared identifier is reported only once for each function it appears in
[perfbuilder@60d5802468f6 perf]$ /arc_gnu_2019.03-rc1_prebuilt_uclibc_le_archs_linux_install/bin/arc-linux-gcc --version | head -1
arc-linux-gcc (ARCv2 ISA Linux uClibc toolchain 2019.03-rc1) 8.3.1 20190225
[perfbuilder@60d5802468f6 perf]$
Trying to reproduce a report by Vineet, I noticed that, with just
cross-built zlib and numactl libraries, I ended up with the above
failure.
So, since RUSAGE_THREAD is available as a define, check for that and
numactl libraries, I ended up with the above failure.
So, since RUSAGE_THREAD is available as a define in the system headers,
check if it is defined in the 'perf bench numa' sources and define it if
not.
Now it builds and I have to figure out if the problem reported by Vineet
only takes place if we have libelf or some other library available.
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: linux-snps-arc@lists.infradead.org
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Vineet Gupta <Vineet.Gupta1@synopsys.com>
Link: https://lkml.kernel.org/n/tip-2wb4r1gir9xrevbpq7qp0amk@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The traceevent lib is used by the perf tool, and when executing
perf test -v 6
it outputs error log on the ARM64 platform:
running test 33 '*:*'trace-cmd: No such file or directory
[...]
trace-cmd: Invalid argument
The trace event parsing code originally came from trace-cmd so it keeps
the tag string "trace-cmd" for errors, this easily introduces the
impression that the perf tool launches trace-cmd command for trace event
parsing, but in fact the related parsing is accomplished by the
traceevent lib.
This patch changes the tag string to "libtraceevent" so that we can
avoid confusion and let users to more easily connect the error with
traceevent lib.
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20190424013802.27569-1-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Commit 6987561c9e86 ("perf annotate: Enable annotation of BPF programs") adds
support for BPF programs annotations but the new code does not build on 32-bit.
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Acked-by: Song Liu <songliubraving@fb.com>
Fixes: 6987561c9e86 ("perf annotate: Enable annotation of BPF programs")
Link: http://lkml.kernel.org/r/20190403194452.10845-1-cascardo@canonical.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To pick up the changes from:
2b27924bb1d4 ("KVM: nVMX: always use early vmcs check when EPT is disabled")
That causes this object in the tools/perf build process to be rebuilt:
CC /tmp/build/perf/arch/x86/util/kvm-stat.o
But it isn't using VMX_ABORT_ prefixed constants, so no change in
behaviour.
This silences this perf build warning:
Warning: Kernel ABI header at 'tools/arch/x86/include/uapi/asm/vmx.h' differs from latest version at 'arch/x86/include/uapi/asm/vmx.h'
diff -u tools/arch/x86/include/uapi/asm/vmx.h arch/x86/include/uapi/asm/vmx.h
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Link: https://lkml.kernel.org/n/tip-bjbo3zc0r8i8oa0udpvftya6@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
In perf_env__find_btf(), we're returning without unlocking
"env->bpf_progs.lock". There may be cause lockdep issue.
Detected by CoversityScan, CID# 1444762:(program hangs(LOCK))
Signed-off-by: Bo YU <tsu.yubo@gmail.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Cc: bpf@vger.kernel.org
Cc: netdev@vger.kernel.org
Fixes: 2db7b1e0bd49d: (perf bpf: Return NULL when RB tree lookup fails in perf_env__find_btf())
Link: http://lkml.kernel.org/r/20190422080138.10088-1-tsu.yubo@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add an explicit subdirectory specification for arch/x86/events/amd to
the MAINTAINERS file, to distinguish it from its parent. This will
produce the correct set of maintainers for the files found therein.
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Gary Hook <Gary.Hook@amd.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Liška <mliska@suse.cz>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Pu Wen <puwen@hygon.cn>
Cc: Stephane Eranian <eranian@google.com>
Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Lendacky <Thomas.Lendacky@amd.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: linux-kernel@vger.kernel.org
Fixes: 39b0332a2158 ("perf/x86: Move perf_event_amd.c ........... => x86/events/amd/core.c")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Add a new amd_hw_cache_event_ids_f17h assignment structure set
for AMD families 17h and above, since a lot has changed. Specifically:
L1 Data Cache
The data cache access counter remains the same on Family 17h.
For DC misses, PMCx041's definition changes with Family 17h,
so instead we use the L2 cache accesses from L1 data cache
misses counter (PMCx060,umask=0xc8).
For DC hardware prefetch events, Family 17h breaks compatibility
for PMCx067 "Data Prefetcher", so instead, we use PMCx05a "Hardware
Prefetch DC Fills."
L1 Instruction Cache
PMCs 0x80 and 0x81 (32-byte IC fetches and misses) are backward
compatible on Family 17h.
For prefetches, we remove the erroneous PMCx04B assignment which
counts how many software data cache prefetch load instructions were
dispatched.
LL - Last Level Cache
Removing PMCs 7D, 7E, and 7F assignments, as they do not exist
on Family 17h, where the last level cache is L3. L3 counters
can be accessed using the existing AMD Uncore driver.
Data TLB
On Intel machines, data TLB accesses ("dTLB-loads") are assigned
to counters that count load/store instructions retired. This
is inconsistent with instruction TLB accesses, where Intel
implementations report iTLB misses that hit in the STLB.
Ideally, dTLB-loads would count higher level dTLB misses that hit
in lower level TLBs, and dTLB-load-misses would report those
that also missed in those lower-level TLBs, therefore causing
a page table walk. That would be consistent with instruction
TLB operation, remove the redundancy between dTLB-loads and
L1-dcache-loads, and prevent perf from producing artificially
low percentage ratios, i.e. the "0.01%" below:
42,550,869 L1-dcache-loads
41,591,860 dTLB-loads
4,802 dTLB-load-misses # 0.01% of all dTLB cache hits
7,283,682 L1-dcache-stores
7,912,392 dTLB-stores
310 dTLB-store-misses
On AMD Families prior to 17h, the "Data Cache Accesses" counter is
used, which is slightly better than load/store instructions retired,
but still counts in terms of individual load/store operations
instead of TLB operations.
So, for AMD Families 17h and higher, this patch assigns "dTLB-loads"
to a counter for L1 dTLB misses that hit in the L2 dTLB, and
"dTLB-load-misses" to a counter for L1 DTLB misses that caused
L2 DTLB misses and therefore also caused page table walks. This
results in a much more accurate view of data TLB performance:
60,961,781 L1-dcache-loads
4,601 dTLB-loads
963 dTLB-load-misses # 20.93% of all dTLB cache hits
Note that for all AMD families, data loads and stores are combined
in a single accesses counter, so no 'L1-dcache-stores' are reported
separately, and stores are counted with loads in 'L1-dcache-loads'.
Also note that the "% of all dTLB cache hits" string is misleading
because (a) "dTLB cache": although TLBs can be considered caches for
page tables, in this context, it can be misinterpreted as data cache
hits because the figures are similar (at least on Intel), and (b) not
all those loads (technically accesses) technically "hit" at that
hardware level. "% of all dTLB accesses" would be more clear/accurate.
Instruction TLB
On Intel machines, 'iTLB-loads' measure iTLB misses that hit in the
STLB, and 'iTLB-load-misses' measure iTLB misses that also missed in
the STLB and completed a page table walk.
For AMD Family 17h and above, for 'iTLB-loads' we replace the
erroneous instruction cache fetches counter with PMCx084
"L1 ITLB Miss, L2 ITLB Hit".
For 'iTLB-load-misses' we still use PMCx085 "L1 ITLB Miss,
L2 ITLB Miss", but set a 0xff umask because without it the event
does not get counted.
Branch Predictor (BPU)
PMCs 0xc2 and 0xc3 continue to be valid across all AMD Families.
Node Level Events
Family 17h does not have a PMCx0e9 counter, and corresponding counters
have not been made available publicly, so for now, we mark them as
unsupported for Families 17h and above.
Reference:
"Open-Source Register Reference For AMD Family 17h Processors Models 00h-2Fh"
Released 7/17/2018, Publication #56255, Revision 3.03:
https://www.amd.com/system/files/TechDocs/56255_OSRR.pdf
[ mingo: tidied up the line breaks. ]
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Cc: <stable@vger.kernel.org> # v4.9+
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Liška <mliska@suse.cz>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Pu Wen <puwen@hygon.cn>
Cc: Stephane Eranian <eranian@google.com>
Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Lendacky <Thomas.Lendacky@amd.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: linux-kernel@vger.kernel.org
Cc: linux-perf-users@vger.kernel.org
Fixes: e40ed1542dd7 ("perf/x86: Add perf support for AMD family-17h processors")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull power supply fixes from Sebastian Reichel:
"Two more fixes for the 5.1 cycle.
One division by zero fix in a specific driver and one core workaround
for bad userspace behaviour from systemd regarding uevents. IMHO this
can be considered to be a userspace bug, but the debug messages are
useless anyways
- cpcap-battery: fix a division by zero
- core: fix systemd issue due to log messages produced by uevent"
* tag 'for-v5.1-rc' of git://git.kernel.org/pub/scm/linux/kernel/git/sre/linux-power-supply:
power: supply: sysfs: prevent endless uevent loop with CONFIG_POWER_SUPPLY_DEBUG
power: supply: cpcap-battery: Fix division by zero
Pull ARC fixes from Vineet Gupta:
"A few minor fixes for ARC.
- regression in memset if line size !64
- avoid panic if PAE and IOC"
* tag 'arc-5.1-final' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
ARC: memset: fix build with L1_CACHE_SHIFT != 6
ARC: [hsdk] Make it easier to add PAE40 region to DTB
ARC: PAE40: don't panic and instead turn off hw ioc
Fix a similar endless event loop as was done in commit
8dcf32175b4e ("i2c: prevent endless uevent loop with
CONFIG_I2C_DEBUG_CORE"):
The culprit is the dev_dbg printk in the i2c uevent handler. If
this is activated (for instance by CONFIG_I2C_DEBUG_CORE) it results
in an endless loop with systemd-journald.
This happens if user-space scans the system log and reads the uevent
file to get information about a newly created device, which seems
fair use to me. Unfortunately reading the "uevent" file uses the
same function that runs for creating the uevent for a new device,
generating the next syslog entry
Both CONFIG_I2C_DEBUG_CORE and CONFIG_POWER_SUPPLY_DEBUG were reported
in https://bugs.freedesktop.org/show_bug.cgi?id=76886 but only former
seems to have been fixed. Drop debug prints as it was done in I2C
subsystem to resolve the issue.
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Cc: Chris Healy <cphealy@gmail.com>
Cc: linux-pm@vger.kernel.org
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>