We just check that the evsel is the one we associated with the
bpf-output event associated with the "__augmented_syscalls__" eBPF map,
to show that the formatting is done properly:
# perf trace -e perf/tools/perf/examples/bpf/augmented_syscalls.c,openat cat /etc/passwd > /dev/null
0.000 ( ): __augmented_syscalls__:dfd: CWD, filename: 0x43e06da8, flags: CLOEXEC
0.006 ( ): syscalls:sys_enter_openat:dfd: CWD, filename: 0x43e06da8, flags: CLOEXEC
0.007 ( 0.004 ms): cat/11486 openat(dfd: CWD, filename: 0x43e06da8, flags: CLOEXEC ) = 3
0.029 ( ): __augmented_syscalls__:dfd: CWD, filename: 0x4400ece0, flags: CLOEXEC
0.030 ( ): syscalls:sys_enter_openat:dfd: CWD, filename: 0x4400ece0, flags: CLOEXEC
0.031 ( 0.004 ms): cat/11486 openat(dfd: CWD, filename: 0x4400ece0, flags: CLOEXEC ) = 3
0.249 ( ): __augmented_syscalls__:dfd: CWD, filename: 0xc3700d6
0.250 ( ): syscalls:sys_enter_openat:dfd: CWD, filename: 0xc3700d6
0.252 ( 0.003 ms): cat/11486 openat(dfd: CWD, filename: 0xc3700d6 ) = 3
#
Now we just need to get the full blown enter/exit handlers to check if the
evsel being processed is the augmented_syscalls one to go pick the pointer
payloads from the end of the payload.
We also need to state somehow what is the layout for multi pointer arg syscalls.
Also handy would be to have a BTF file with the struct definitions used in
syscalls, compact, generated at kernel built time and available for use in eBPF
programs.
Till we get there we can go on doing some manual coupling of the most relevant
syscalls with some hand built beautifiers.
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: https://lkml.kernel.org/n/tip-r6ba5izrml82nwfmwcp7jpkm@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add an example BPF script that writes syscalls:sys_enter_openat raw
tracepoint payloads augmented with the first 64 bytes of the "filename"
syscall pointer arg.
Then catch it and print it just like with things written to the
"__bpf_stdout__" map associated with a PERF_COUNT_SW_BPF_OUTPUT software
event, by just letting the default tracepoint handler in 'perf trace',
trace__event_handler(), to use bpf_output__fprintf(trace, sample), just
like it does with all other PERF_COUNT_SW_BPF_OUTPUT events, i.e. just
do a dump on the payload, so that we can check if what is being printed
has at least the first 64 bytes of the "filename" arg:
The augmented_syscalls.c eBPF script:
# cat tools/perf/examples/bpf/augmented_syscalls.c
// SPDX-License-Identifier: GPL-2.0
#include <stdio.h>
struct bpf_map SEC("maps") __augmented_syscalls__ = {
.type = BPF_MAP_TYPE_PERF_EVENT_ARRAY,
.key_size = sizeof(int),
.value_size = sizeof(u32),
.max_entries = __NR_CPUS__,
};
struct syscall_enter_openat_args {
unsigned long long common_tp_fields;
long syscall_nr;
long dfd;
char *filename_ptr;
long flags;
long mode;
};
struct augmented_enter_openat_args {
struct syscall_enter_openat_args args;
char filename[64];
};
int syscall_enter(openat)(struct syscall_enter_openat_args *args)
{
struct augmented_enter_openat_args augmented_args;
probe_read(&augmented_args.args, sizeof(augmented_args.args), args);
probe_read_str(&augmented_args.filename, sizeof(augmented_args.filename), args->filename_ptr);
perf_event_output(args, &__augmented_syscalls__, BPF_F_CURRENT_CPU,
&augmented_args, sizeof(augmented_args));
return 1;
}
license(GPL);
#
So it will just prepare a raw_syscalls:sys_enter payload for the
"openat" syscall.
This will eventually be done for all syscalls with pointer args,
globally or just when the user asks, using some spec, which args of
which syscalls it wants "expanded" this way, we'll probably start with
just all the syscalls that have char * pointers with familiar names, the
ones we already handle with the probe:vfs_getname kprobe if it is in
place hooking the kernel getname_flags() function used to copy from user
the paths.
Running it we get:
# perf trace -e perf/tools/perf/examples/bpf/augmented_syscalls.c,openat cat /etc/passwd > /dev/null
0.000 ( ): __augmented_syscalls__:X?.C......................`\..................../etc/ld.so.cache..#......,....ao.k...............k......1.".........
0.006 ( ): syscalls:sys_enter_openat:dfd: CWD, filename: 0x5c600da8, flags: CLOEXEC
0.008 ( 0.005 ms): cat/31292 openat(dfd: CWD, filename: 0x5c600da8, flags: CLOEXEC ) = 3
0.036 ( ): __augmented_syscalls__:X?.C.......................\..................../lib64/libc.so.6......... .\....#........?.......=.C..../.".........
0.037 ( ): syscalls:sys_enter_openat:dfd: CWD, filename: 0x5c808ce0, flags: CLOEXEC
0.039 ( 0.007 ms): cat/31292 openat(dfd: CWD, filename: 0x5c808ce0, flags: CLOEXEC ) = 3
0.323 ( ): __augmented_syscalls__:X?.C.....................P....................../etc/passwd......>.C....@................>.C.....,....ao.>.C........
0.325 ( ): syscalls:sys_enter_openat:dfd: CWD, filename: 0xe8be50d6
0.327 ( 0.004 ms): cat/31292 openat(dfd: CWD, filename: 0xe8be50d6 ) = 3
#
We need to go on optimizing this to avoid seding trash or zeroes in the
pointer content payload, using the return from bpf_probe_read_str(), but
to keep things simple at this stage and make incremental progress, lets
leave it at that for now.
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: https://lkml.kernel.org/n/tip-g360n1zbj6bkbk6q0qo11c28@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
That, together with the map __bpf_output__ that is already handled by
'perf trace' to print that event's contents as strings provides a
debugging facility, to show it in use, print a simple string everytime
the syscalls:sys_enter_openat() syscall tracepoint is hit:
# cat tools/perf/examples/bpf/hello.c
#include <stdio.h>
int syscall_enter(openat)(void *args)
{
puts("Hello, world\n");
return 0;
}
license(GPL);
#
# perf trace -e openat,tools/perf/examples/bpf/hello.c cat /etc/passwd > /dev/null
0.016 ( ): __bpf_stdout__:Hello, world
0.018 ( 0.010 ms): cat/9079 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC) = 3
0.057 ( ): __bpf_stdout__:Hello, world
0.059 ( 0.011 ms): cat/9079 openat(dfd: CWD, filename: /lib64/libc.so.6, flags: CLOEXEC) = 3
0.417 ( ): __bpf_stdout__:Hello, world
0.419 ( 0.009 ms): cat/9079 openat(dfd: CWD, filename: /etc/passwd) = 3
#
This is part of an ongoing experimentation on making eBPF scripts as
consumed by perf to be as concise as possible and using familiar
concepts such as stdio.h functions, that end up just wrapping the
existing BPF functions, trying to hide as much boilerplate as possible
while using just conventions and C preprocessor tricks.
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: https://lkml.kernel.org/n/tip-4tiaqlx5crf0fwpe7a6j84x7@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Set annotation percent type from following choices:
global-period, local-period, global-hits, local-hits
With following report option setup the percent type will be passed to
annotation browser:
$ perf report --percent-type period-local
The local/global keywords set if the percentage is computed in the scope
of the function (local) or the whole data (global). The period/hits
keywords set the base the percentage is computed on - the samples period
or the number of samples (hits).
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/20180804130521.11408-21-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add --percent-type option to set annotation percent type from following
choices:
global-period, local-period, global-hits, local-hits
Examples:
$ perf annotate --percent-type period-local --stdio | head -1
Percent | Source code ... es, percent: local period)
$ perf annotate --percent-type hits-local --stdio | head -1
Percent | Source code ... es, percent: local hits)
$ perf annotate --percent-type hits-global --stdio | head -1
Percent | Source code ... es, percent: global hits)
$ perf annotate --percent-type period-global --stdio | head -1
Percent | Source code ... es, percent: global period)
The local/global keywords set if the percentage is computed in the scope
of the function (local) or the whole data (global).
The period/hits keywords set the base the percentage is computed on -
the samples period or the number of samples (hits).
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/20180804130521.11408-20-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
In following patches we will allow to switch percent type even for stdio
annotation outputs. Adding the percent type value into the annotation
outputs title.
$ perf annotate --stdio
Percent | Sou ... instructions:u } (2805 samples, percent: local period)
--------------------------- ... ------------------------------------------------------
...
$ perf annotate --stdio2
Samples: 2K of events 'anon ... count (approx.): 156525487, [percent: local period]
safe_write.c() /usr/bin/yes
Percent
...
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/20180804130521.11408-19-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We have more current function tto get the title for annotation,
which is hists__scnprintf_title. They both have same output as
far as the annotation's header line goes.
They differ in counting of the nr_samples, hists__scnprintf_title
provides more accurate number based on the setup of the
symbol_conf.filter_relative variable.
Plus it also displays any uid/thread/dso/socket filters/zooms
if there are set any, which annotation__scnprintf_samples_period
does not.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/20180804130521.11408-4-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Allowing one to hook into the syscalls:sys_enter_NAME tracepoints,
an example is provided that hooks into the 'openat' syscall.
Using it with the probe:vfs_getname probe into getname_flags to get the
filename args as it is copied from userspace:
# perf probe -l
probe:vfs_getname (on getname_flags:73@acme/git/linux/fs/namei.c with pathname)
# perf trace -e probe:*getname,tools/perf/examples/bpf/sys_enter_openat.c cat /etc/passwd > /dev/null
0.000 probe:vfs_getname:(ffffffffbd2a8983) pathname="/etc/ld.so.preload"
0.022 syscalls:sys_enter_openat:dfd: CWD, filename: 0xafbe8da8, flags: CLOEXEC
0.027 probe:vfs_getname:(ffffffffbd2a8983) pathname="/etc/ld.so.cache"
0.054 syscalls:sys_enter_openat:dfd: CWD, filename: 0xafdf0ce0, flags: CLOEXEC
0.057 probe:vfs_getname:(ffffffffbd2a8983) pathname="/lib64/libc.so.6"
0.316 probe:vfs_getname:(ffffffffbd2a8983) pathname="/usr/lib/locale/locale-archive"
0.375 syscalls:sys_enter_openat:dfd: CWD, filename: 0xe2b2b0b4
0.379 probe:vfs_getname:(ffffffffbd2a8983) pathname="/etc/passwd"
#
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: https://lkml.kernel.org/n/tip-2po9jcqv1qgj0koxlg8kkg30@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add support for s390 auxiliary trace support.
Use 'perf record -e rbd000 -- ls' to create the perf.data file.
Use 'perf report' to display the auxiliary trace data.
Output before:
[root@s35lp76 perf]# ./perf report --stdio
0x128 [0x10]: failed to process type: 70
Error:
failed to process sample
[root@s35lp76 perf]#
Output after:
[root@s35lp76 perf]# ./perf report --stdio
18.21% 18.21% ls [kernel.kallsyms] [k] ftrace_likely_update
9.52% 9.52% ls [kernel.kallsyms] [k] lock_acquire
9.38% 9.38% ls [kernel.kallsyms] [k] lock_release
3.45% 3.45% ls [kernel.kallsyms] [k] lock_acquired
2.88% 2.88% ls [kernel.kallsyms] [k] link_path_walk
2.63% 2.63% ls [kernel.kallsyms] [k] __d_lookup
2.38% 2.38% ls [kernel.kallsyms] [k] __d_lookup_rcu
2.04% 2.04% ls [kernel.kallsyms] [k] ___might_sleep
1.83% 1.83% ls [kernel.kallsyms] [k] debug_lockdep_rcu_enabled
1.44% 1.44% ls [kernel.kallsyms] [k] dput
....
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Link: http://lkml.kernel.org/r/20180802074622.13641-4-tmricht@linux.ibm.com
[ Use PRI[xd]64 to fix the build on debian:experimental-x-mips (gcc 8.1.0) and others ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add support for s390 auxiliary trace support.
Use 'perf record -e rbd000' to create the perf.data file. The event
also has the symbolic name SF_CYCLES_BASIC_DIAG, using 'perf record -e
SF_CYCLES_BASIC_DIAG' is equivalent.
Use 'perf report -D' to display the auxiliary trace data.
Output before:
0 0 0x25a66 [0x30]: PERF_RECORD_AUXTRACE size: 0x40000
offset: 0 ref: 0 idx: 4 tid: -1 cpu: 4
Nothing else
Output after:
0 0 0x25a66 [0x30]: PERF_RECORD_AUXTRACE size: 0x40000
offset: 0 ref: 0 idx: 4 tid: -1 cpu: 4
.
. ... s390 AUX data: size 262144 bytes
[00000000] Basic Def:0001 Inst:0000 TW AS:3 ASN:0xffff IA:0x0000000000c2f1bc
CL:1 HPP:0x8000000000000000 GPP:000000000000000000
[0x000020] Diag Def:8005
[0x0000bf] Basic Def:0001 Inst:0000 TW AS:3 ASN:0xffff IA:0x0000000000c2f1bc
CL:1 HPP:0x8000000000000000 GPP:000000000000000000
[0x0000df] Diag Def:8005
[0x00017e] Basic Def:0001 Inst:0000 TW AS:3 ASN:0xffff IA:0x0000000000c2f1bc
CL:1 HPP:0x8000000000000000 GPP:000000000000000000
....
[0x000fc0] Trailer F T bsdes:32 dsdes:159 Overflow:0 Time:0xd4ab59a8450fa108
C:1 TOD:0xd4ab4ec98ceb3832 1:0x8000000000000000 2:0xd4ab4ec98ceb3832
This output is shown for every sampled data block. The
output contains the
- basic-sampling data entry
- diagnostic-sampling data entry
- trailer entry
The basic sampling entry and diagnostic sampling entry sizes can be
extracted using the trailer entries in the SDB. On older hardware these
values (bsdes and dsdes in the trailer entry) are reserved and zero.
Older hardware use hard coded values based on the s390 machine type.
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Link: http://lkml.kernel.org/r/20180802074622.13641-3-tmricht@linux.ibm.com
Link: http://lkml.kernel.org/r/eda2632e-7919-5ffd-5f68-821e77d216fa@linux.ibm.com
[ Merged a fix for a 'tipe puned' problem reported by Michael Ellerman see last Link tag. ]
[ Removed __packed from two structs, they're already naturally packed and having that. ]
[ attribute breaks the build in gcc 8.1.1 mips, 4.4.7 x86_64, 7.1.1 ARCompact ISA, etc) ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add initial support for s390 auxiliary traces using the CPU-Measurement
Sampling Facility.
Support and ignore PERF_REPORT_AUXTRACE_INFO records in the perf data
file. Later patches will show the contents of the auxiliary traces.
Setup the auxtrace queues and data structures for s390. A raw dump of
the perf.data file now does not show an error when an auxtrace event is
encountered.
Output before:
[root@s35lp76 perf]# ./perf report -D -i perf.data.auxtrace
0x128 [0x10]: failed to process type: 70
Error:
failed to process sample
0x128 [0x10]: event: 70
.
. ... raw event: size 16 bytes
. 0000: 00 00 00 46 00 00 00 10 00 00 00 00 00 00 00 00 ...F............
0x128 [0x10]: PERF_RECORD_AUXTRACE_INFO type: 0
[root@s35lp76 perf]#
Output after:
# ./perf report -D -i perf.data.auxtrace |fgrep PERF_RECORD_AUXTRACE
0 0 0x128 [0x10]: PERF_RECORD_AUXTRACE_INFO type: 5
0 0 0x25a66 [0x30]: PERF_RECORD_AUXTRACE size: 0x40000
offset: 0 ref: 0 idx: 4 tid: -1 cpu: 4
....
Additional notes about the underlying hardware and software
implementation, provided by Hendrik Brueckner (see Link: below).
=============================================================================
The CPU-Measurement Facility (CPU-MF) provides a set of functions to obtain
performance information on the mainframe. Basically, it was introduced
with System z10 years ago for the z/Architecture, that means, 64-bit.
For Linux, there are two facilities of interest, counter facility and sampling
facility. The counter facility provides hardware counters for instructions,
cycles, crypto-activities, and many more.
The sampling facility is a hardware sampler that when started will write
samples at a particular interval into a sampling buffer. At some point,
for example, if a sample block is full, it generates an interrupt to collect
samples (while the sampler continues to run).
Few years ago, I started to provide the a perf PMU to use the counter
and sampling facilities. Recently, the device driver was updated to also
"export" the sampling buffer into the AUX area. Thomas now completed the
related perf work to interpret and process these AUX data.
If people are more interested in the sampling facility, they can have a
look into:
- The Load-Program-Parameter and the CPU-Measurement Facilities, SA23-2260-05
http://www-01.ibm.com/support/docview.wss?uid=isg26fcd1cc32246f4c8852574ce0044734a
and to learn how-to use it for Linux on Z, have look at chapter 54,
"Using the CPU-measurement facilities" in the:
- Device Drivers, Features, and Commands, SC33-8411-34
http://public.dhe.ibm.com/software/dw/linux390/docu/l416dd34.pdf
=============================================================================
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Link: http://lkml.kernel.org/r/20180803100758.GA28475@linux.ibm.com
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Link: http://lkml.kernel.org/r/20180802074622.13641-2-tmricht@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To avoid having to ask libtraceevent to find a field by name when
handling each tracepoint event, we setup a struct syscall_tp with
a tp_field struct having an extractor function + the offset for the
"id", "args" and "ret" raw_syscalls:sys_{enter,exit} tracepoints.
Now that we want to do the same with syscalls:sys_{entry,exit}_NAME
individual syscall tracepoints, where we have "id" as "__syscall_nr" and
"args" as the actual series of per syscall parameters, we need more
flexibility from the routines that set up these pre-looked up syscall
tracepoint arg fields.
The next cset will use it.
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: Steven Rostedt <rostedt@goodmis.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-v59q5e0jrlzkpl9a1c7t81ni@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We were using the beautifiers only when processing the
raw_syscalls:sys_enter events, but we can as well use them for the
syscalls:sys_enter_NAME events, as the layout is the same.
Some more tweaking is needed as we're processing them straight away,
i.e. there is no buffering in the sys_enter_NAME event to wait for
things like vfs_getname to provide pointer contents and then flushing
at sys_exit_NAME, so we need to state in the syscall_arg that this
is unbuffered, just print the pointer values, beautifying just
non-pointer syscall args.
This just shows an alternative way of processing tracepoints, that we
will end up using when creating "tracepoint" payloads that already copy
pointer contents (or chunks of it, i.e. not the whole filename, but just
the end of it, not all the bf for a read/write, but just the start,
etc), directly in the kernel using eBPF.
E.g.:
# perf trace -e syscalls:*enter*sleep,*sleep sleep 1
0.303 ( ): syscalls:sys_enter_nanosleep:rqtp: 0x7ffc93d5ecc0
0.305 (1000.229 ms): sleep/8746 nanosleep(rqtp: 0x7ffc93d5ecc0) = 0
# perf trace -e syscalls:*_*sleep,*sleep sleep 1
0.288 ( ): syscalls:sys_enter_nanosleep:rqtp: 0x7ffecde87e40
0.289 ( ): sleep/8748 nanosleep(rqtp: 0x7ffecde87e40) ...
1000.479 ( ): syscalls:sys_exit_nanosleep:0x0
0.289 (1000.208 ms): sleep/8748 ... [continued]: nanosleep()) = 0
#
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: Steven Rostedt <rostedt@goodmis.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-jehyd2zwhw00z3p7v7mg9632@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When the vfs_getname() wannabe tracepoint is in place:
# perf probe -l
probe:vfs_getname (on getname_flags:73@acme/git/linux/fs/namei.c with pathname)
#
'perf trace' will use it to get the pathname when it is copied from
userspace to the kernel, right after syscalls:sys_enter_open, copied
in the 'probe:vfs_getname', stash it somewhere and then, at
syscalls:sys_exit_open time, if the 'open' return is not -1, i.e. a
successfull open syscall, associate that pathname to this return, i.e.
the fd.
We were not doing this for the 'openat' syscall, which would cause 'perf
trace' to fallback to using /proc to get the fd, change it so that we
use what we got from probe:vfs_getname, reducing the 'openat'
beautification process cost, ditching the syscalls performed to read
procfs state and avoiding some possible races in the process.
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: https://lkml.kernel.org/n/tip-xnp44ao3bkb6ejeczxfnjwsh@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The next example scripts need the definition for the BPF functions, i.e.
things like BPF_FUNC_probe_read, and in time will require lots of other
definitions found in uapi/linux/bpf.h, so include it from the bpf.h file
included from the eBPF scripts build with clang via '-e bpf_script.c'
like in this example:
$ tail -8 tools/perf/examples/bpf/5sec.c
#include <bpf.h>
int probe(hrtimer_nanosleep, rqtp->tv_sec)(void *ctx, int err, long sec)
{
return sec == 5;
}
license(GPL);
$
That 'bpf.h' include in the 5sec.c eBPF example will come from a set of
header files crafted for building eBPF objects, that in a end-user
system will come from:
/usr/lib/perf/include/bpf/bpf.h
And will include <uapi/linux/bpf.h> either from the place where the
kernel was built, or from a kernel-devel rpm package like:
-working-directory /lib/modules/4.17.9-100.fc27.x86_64/build
That is set up by tools/perf/util/llvm-utils.c, and can be overriden
by setting the 'kbuild-dir' variable in the "llvm" ~/.perfconfig file,
like:
# cat ~/.perfconfig
[llvm]
kbuild-dir = /home/foo/git/build/linux
This usually doesn't need any change, just documenting here my findings
while working with this code.
In the future we may want to instead just use what is in
/usr/include/linux/bpf.h, that comes from the UAPI provided from the
kernel sources, for now, to avoid getting the kernel's non-UAPI
"linux/bpf.h" file, that will cause clang to fail and is not what we
want anyway (no BPF function definitions, etc), do it explicitely by
asking for "uapi/linux/bpf.h".
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: https://lkml.kernel.org/n/tip-zd8zeyhr2sappevojdem9xxt@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
After update of kernel, the perf tool doesn't run anymore on my 32MB RAM
powerpc board, but still runs on a 128MB RAM board:
~# strace perf
execve("/usr/sbin/perf", ["perf"], [/* 12 vars */]) = -1 ENOMEM (Cannot allocate memory)
--- SIGSEGV {si_signo=SIGSEGV, si_code=SI_KERNEL, si_addr=0} ---
+++ killed by SIGSEGV +++
Segmentation fault
objdump -x shows that .bss section has a huge size of 24Mbytes:
27 .bss 016baca8 101cebb8 101cebb8 001cd988 2**3
With especially the following objects having quite big size:
10205f80 l O .bss 00140000 runtime_cycles_stats
10345f80 l O .bss 00140000 runtime_stalled_cycles_front_stats
10485f80 l O .bss 00140000 runtime_stalled_cycles_back_stats
105c5f80 l O .bss 00140000 runtime_branches_stats
10705f80 l O .bss 00140000 runtime_cacherefs_stats
10845f80 l O .bss 00140000 runtime_l1_dcache_stats
10985f80 l O .bss 00140000 runtime_l1_icache_stats
10ac5f80 l O .bss 00140000 runtime_ll_cache_stats
10c05f80 l O .bss 00140000 runtime_itlb_cache_stats
10d45f80 l O .bss 00140000 runtime_dtlb_cache_stats
10e85f80 l O .bss 00140000 runtime_cycles_in_tx_stats
10fc5f80 l O .bss 00140000 runtime_transaction_stats
11105f80 l O .bss 00140000 runtime_elision_stats
11245f80 l O .bss 00140000 runtime_topdown_total_slots
11385f80 l O .bss 00140000 runtime_topdown_slots_retired
114c5f80 l O .bss 00140000 runtime_topdown_slots_issued
11605f80 l O .bss 00140000 runtime_topdown_fetch_bubbles
11745f80 l O .bss 00140000 runtime_topdown_recovery_bubbles
This is due to commit 4d255766d2 ("perf: Bump max number of cpus
to 1024"), because many tables are sized with MAX_NR_CPUS
This patch gives the opportunity to redefine MAX_NR_CPUS via
$ make EXTRA_CFLAGS=-DMAX_NR_CPUS=1
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/20170922112043.8349468C57@po15668-vm-win7.idsi0.si.c-s.fr
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Before:
libbpf: license of tools/perf/examples/bpf/etcsnoop.c is GPL
libbpf: section(6) version, size 4, link 0, flags 3, type=1
libbpf: kernel version of tools/perf/examples/bpf/etcsnoop.c is 41200
libbpf: section(7) .symtab, size 120, link 1, flags 0, type=2
bpf: config program 'syscalls:sys_enter_openat'
libbpf: load bpf program failed: Operation not permitted
libbpf: failed to load program 'syscalls:sys_enter_openat'
libbpf: failed to load object 'tools/perf/examples/bpf/etcsnoop.c'
bpf: load objects failed
After: (just the last line changes)
bpf: load objects failed: err=-4009: (Incorrect kernel version)
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: https://lkml.kernel.org/n/tip-wi44iid0yjfht3lcvplc75fm@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
PMU event descriptions use 7 spaces + '[' or 8 spaces as indentation.
Metric groups used a tab + '['. This patch unifies it to the way PMU
event descriptions are indented.
BEFORE:
$ perf list
[...]
Metric Groups:
DSB:
DSB_Coverage
[Fraction of Uops delivered by the DSB (aka Decoded Icache; or Uop Cache)]
[...]
AFTER:
$ perf list
[...]
Metric Groups:
DSB:
DSB_Coverage
[Fraction of Uops delivered by the DSB (aka Decoded Icache; or Uop Cache)]
[...]
Signed-off-by: Michael Petlan <mpetlan@redhat.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Kim Phillips <kim.phillips@arm.com>
LPU-Reference: 771439042.22924766.1532986504631.JavaMail.zimbra@redhat.com
Link: https://lkml.kernel.org/n/tip-mlo850517m6u1rbjndvd1bwr@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
