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2020-04-24tools/runqslower: Ensure own vmlinux.h is picked up firstAndrii Nakryiko1-1/+1
Reorder include paths to ensure that runqslower sources are picking up vmlinux.h, generated by runqslower's own Makefile. When runqslower is built from selftests/bpf, due to current -I$(BPF_INCLUDE) -I$(OUTPUT) ordering, it might pick up not-yet-complete vmlinux.h, generated by selftests Makefile, which could lead to compilation errors like [0]. So ensure that -I$(OUTPUT) goes first and rely on runqslower's Makefile own dependency chain to ensure vmlinux.h is properly completed before source code relying on it is compiled. [0] https://travis-ci.org/github/libbpf/libbpf/jobs/677905925 Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-04-24bpftool: Respect the -d option in struct_ops cmdMartin KaFai Lau1-1/+7
In the prog cmd, the "-d" option turns on the verifier log. This is missed in the "struct_ops" cmd and this patch fixes it. Fixes: 65c93628599d ("bpftool: Add struct_ops support") Signed-off-by: Martin KaFai Lau <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Reviewed-by: Quentin Monnet <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-04-24selftests/bpf: Add test for freplace program with expected_attach_typeToke Høiland-Jørgensen3-18/+58
This adds a new selftest that tests the ability to attach an freplace program to a program type that relies on the expected_attach_type of the target program to pass verification. Signed-off-by: Toke Høiland-Jørgensen <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-04-24bpf: Fix reStructuredText markupJakub Wilk1-1/+1
The patch fixes: $ scripts/bpf_helpers_doc.py > bpf-helpers.rst $ rst2man bpf-helpers.rst > bpf-helpers.7 bpf-helpers.rst:1105: (WARNING/2) Inline strong start-string without end-string. Signed-off-by: Jakub Wilk <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Reviewed-by: Quentin Monnet <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-04-24Merge tag 'pm-5.7-rc3' of ↵Linus Torvalds5-371/+619
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management fixes from Rafael Wysocki: "Restore an optimization related to asynchronous suspend and resume of devices during system-wide power transitions that was disabled by mistake (Kai-Heng Feng) and update the pm-graph suite of power management utilities (Todd Brandt)" * tag 'pm-5.7-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: PM: sleep: core: Switch back to async_schedule_dev() pm-graph v5.6
2020-04-24selftests/ftrace: Check the first record for kprobe_args_type.tcXiao Yang1-1/+1
It is possible to get multiple records from trace during test and then more than 4 arguments are assigned to ARGS. This situation results in the failure of kprobe_args_type.tc. For example: ----------------------------------------------------------- grep testprobe trace ftracetest-5902 [001] d... 111195.682227: testprobe: (_do_fork+0x0/0x460) arg1=334823024 arg2=334823024 arg3=0x13f4fe70 arg4=7 pmlogger-5949 [000] d... 111195.709898: testprobe: (_do_fork+0x0/0x460) arg1=345308784 arg2=345308784 arg3=0x1494fe70 arg4=7 grep testprobe trace sed -e 's/.* arg1=\(.*\) arg2=\(.*\) arg3=\(.*\) arg4=\(.*\)/\1 \2 \3 \4/' ARGS='334823024 334823024 0x13f4fe70 7 345308784 345308784 0x1494fe70 7' ----------------------------------------------------------- We don't care which process calls do_fork so just check the first record to fix the issue. Signed-off-by: Xiao Yang <[email protected]> Acked-by: Masami Hiramatsu <[email protected]> Signed-off-by: Shuah Khan <[email protected]>
2020-04-23selftests: add build/cross-build dependency check scriptShuah Khan4-9/+291
Add build/cross-build dependency check script kselftest_deps.sh This script does the following: Usage: ./kselftest_deps.sh -[p] <compiler> [test_name] kselftest_deps.sh [-p] gcc kselftest_deps.sh [-p] gcc vm kselftest_deps.sh [-p] aarch64-linux-gnu-gcc kselftest_deps.sh [-p] aarch64-linux-gnu-gcc vm - Should be run in selftests directory in the kernel repo. - Checks if Kselftests can be built/cross-built on a system. - Parses all test/sub-test Makefile to find library dependencies. - Runs compile test on a trivial C file with LDLIBS specified in the test Makefiles to identify missing library dependencies. - Prints suggested target list for a system filtering out tests failed the build dependency check from the TARGETS in Selftests the main Makefile when optional -p is specified. - Prints pass/fail dependency check for each tests/sub-test. - Prints pass/fail targets and libraries. - Default: runs dependency checks on all tests. - Optional test name can be specified to check dependencies for it. To make LDLIBS parsing easier - change gpio and memfd Makefiles to use the same temporary variable used to find and add libraries to LDLIBS. - simlify LDLIBS append logic in intel_pstate/Makefile. Results from run on x86_64 system (trimmed detailed pass/fail list): ======================================================== Kselftest Dependency Check for [./kselftest_deps.sh gcc ] results... ======================================================== Checked tests defining LDLIBS dependencies -------------------------------------------------------- Total tests with Dependencies: 55 Pass: 53 Fail: 2 -------------------------------------------------------- Targets passed build dependency check on system: bpf capabilities filesystems futex gpio intel_pstate membarrier memfd mqueue net powerpc ptp rseq rtc safesetid timens timers vDSO vm -------------------------------------------------------- FAIL: netfilter/Makefile dependency check: -lmnl FAIL: gpio/Makefile dependency check: -lmount -------------------------------------------------------- Targets failed build dependency check on system: gpio netfilter -------------------------------------------------------- Missing libraries system -lmnl -lmount -------------------------------------------------------- ======================================================== Results from run on x86_64 system with aarch64-linux-gnu-gcc: (trimmed detailed pass/fail list): ======================================================== Kselftest Dependency Check for [./kselftest_deps.sh aarch64-linux-gnu-gcc ] results... ======================================================== Checked tests defining LDLIBS dependencies -------------------------------------------------------- Total tests with Dependencies: 55 Pass: 41 Fail: 14 -------------------------------------------------------- Targets failed build dependency check on system: bpf capabilities filesystems futex gpio intel_pstate membarrier memfd mqueue net powerpc ptp rseq rtc timens timers vDSO vm -------------------------------------------------------- -------------------------------------------------------- Targets failed build dependency check on system: bpf capabilities gpio memfd mqueue net netfilter safesetid vm -------------------------------------------------------- Missing libraries system -lcap -lcap-ng -lelf -lfuse -lmnl -lmount -lnuma -lpopt -lz -------------------------------------------------------- ======================================================== Signed-off-by: Shuah Khan <[email protected]>
2020-04-23selftests/ftrace: Check required filter files before running testXiao Yang14-30/+23
Without CONFIG_DYNAMIC_FTRACE, some tests get failure because required filter files(set_ftrace_filter/available_filter_functions/stack_trace_filter) are missing. So implement check_filter_file() and make all related tests check required filter files by it. BTW: set_ftrace_filter and available_filter_functions are introduced together so just check either of them. Signed-off-by: Xiao Yang <[email protected]> Acked-by: Masami Hiramatsu <[email protected]> Signed-off-by: Shuah Khan <[email protected]>
2020-04-23perf record: Add num-synthesize-threads optionStephane Eranian3-2/+37
To control degree of parallelism of the synthesize_mmap() code which is scanning /proc/PID/task/PID/maps and can be time consuming. Mimic perf top way of handling the option. If not specified will default to 1 thread, i.e. default behavior before this option. On a desktop computer the processing of /proc/PID/task/PID/maps isn't slow enough to warrant parallel processing and the thread creation has some cost - hence the default of 1. On a loaded server with >100 cores it is possible to see synthesis times in the order of seconds and in this case having the option is desirable. As the processing is a synchronization point, it is legitimate to worry if Amdahl's law will apply to this patch. Profiling with this patch in place: https://lore.kernel.org/lkml/[email protected]/ shows: ... - 32.59% __perf_event__synthesize_threads - 32.54% __event__synthesize_thread + 22.13% perf_event__synthesize_mmap_events + 6.68% perf_event__get_comm_ids.constprop.0 + 1.49% process_synthesized_event + 1.29% __GI___readdir64 + 0.60% __opendir ... That is the processing is 1.49% of execution time and there is plenty to make parallel. This is shown in the benchmark in this patch: https://lore.kernel.org/lkml/[email protected]/ Computing performance of multi threaded perf event synthesis by synthesizing events on CPU 0: Number of synthesis threads: 1 Average synthesis took: 127729.000 usec (+- 3372.880 usec) Average num. events: 21548.600 (+- 0.306) Average time per event 5.927 usec Number of synthesis threads: 2 Average synthesis took: 88863.500 usec (+- 385.168 usec) Average num. events: 21552.800 (+- 0.327) Average time per event 4.123 usec Number of synthesis threads: 3 Average synthesis took: 83257.400 usec (+- 348.617 usec) Average num. events: 21553.200 (+- 0.327) Average time per event 3.863 usec Number of synthesis threads: 4 Average synthesis took: 75093.000 usec (+- 422.978 usec) Average num. events: 21554.200 (+- 0.200) Average time per event 3.484 usec Number of synthesis threads: 5 Average synthesis took: 64896.600 usec (+- 353.348 usec) Average num. events: 21558.000 (+- 0.000) Average time per event 3.010 usec Number of synthesis threads: 6 Average synthesis took: 59210.200 usec (+- 342.890 usec) Average num. events: 21560.000 (+- 0.000) Average time per event 2.746 usec Number of synthesis threads: 7 Average synthesis took: 54093.900 usec (+- 306.247 usec) Average num. events: 21562.000 (+- 0.000) Average time per event 2.509 usec Number of synthesis threads: 8 Average synthesis took: 48938.700 usec (+- 341.732 usec) Average num. events: 21564.000 (+- 0.000) Average time per event 2.269 usec Where average time per synthesized event goes from 5.927 usec with 1 thread to 2.269 usec with 8. This isn't a linear speed up as not all of synthesize code has been made parallel. If the synthesis time was about 10 seconds then using 8 threads may bring this down to less than 4. Signed-off-by: Stephane Eranian <[email protected]> Reviewed-by: Ian Rogers <[email protected]> Acked-by: Jiri Olsa <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Alexey Budankov <[email protected]> Cc: Kan Liang <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Tony Jones <[email protected]> Cc: yuzhoujian <[email protected]> Link: http://lore.kernel.org/lkml/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2020-04-23perf test session topology: Fix data pathTommi Rantala1-8/+4
Commit 2d4f27999b88 ("perf data: Add global path holder") missed path conversion in tests/topology.c, causing the "Session topology" testcase to "hang" (waits forever for input from stdin) when doing "ssh $VM perf test". Can be reproduced by running "cat | perf test topo", and crashed by replacing cat with true: $ true | perf test -v topo 40: Session topology : --- start --- test child forked, pid 3638 templ file: /tmp/perf-test-QPvAch incompatible file format incompatible file format (rerun with -v to learn more) free(): invalid pointer test child interrupted ---- end ---- Session topology: FAILED! Committer testing: Reproduced the above result before the patch and after it is back working: # true | perf test -v topo 41: Session topology : --- start --- test child forked, pid 19374 templ file: /tmp/perf-test-YOTEQg CPU 0, core 0, socket 0 CPU 1, core 1, socket 0 CPU 2, core 2, socket 0 CPU 3, core 3, socket 0 CPU 4, core 0, socket 0 CPU 5, core 1, socket 0 CPU 6, core 2, socket 0 CPU 7, core 3, socket 0 test child finished with 0 ---- end ---- Session topology: Ok # Fixes: 2d4f27999b88 ("perf data: Add global path holder") Signed-off-by: Tommi Rantala <[email protected]> Tested-by: Arnaldo Carvalho de Melo <[email protected]> Acked-by: Jiri Olsa <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Mamatha Inamdar <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Ravi Bangoria <[email protected]> Link: http://lore.kernel.org/lkml/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2020-04-23perf stat: Improve runtime stat for interval modeJin Yao2-0/+3
For interval mode, the metric is printed after the '#' character if it exists. But it's not calculated by the counts generated in this interval. See the following examples: root@kbl-ppc:~# perf stat -M CPI -I1000 --interval-count 2 # time counts unit events 1.000422803 764,809 inst_retired.any # 2.9 CPI 1.000422803 2,234,932 cycles 2.001464585 1,960,061 inst_retired.any # 1.6 CPI 2.001464585 4,022,591 cycles The second CPI should not be 1.6 (4,022,591/1,960,061 is 2.1) root@kbl-ppc:~# perf stat -e cycles,instructions -I1000 --interval-count 2 # time counts unit events 1.000429493 2,869,311 cycles 1.000429493 816,875 instructions # 0.28 insn per cycle 2.001516426 9,260,973 cycles 2.001516426 5,250,634 instructions # 0.87 insn per cycle The second 'insn per cycle' should not be 0.87 (5,250,634/9,260,973 is 0.57). The current code uses a global variable 'rt_stat' for tracking and updating the std dev of runtime stat. Unlike the counts, 'rt_stat' is not reset for interval. While the counts are reset for interval. perf_stat_process_counter() { if (config->interval) init_stats(ps->res_stats); } So for interval mode, the 'rt_stat' variable should be reset too. This patch resets 'rt_stat' before read_counters(), so the runtime stat is only calculated by the counts generated in this interval. With this patch: root@kbl-ppc:~# perf stat -M CPI -I1000 --interval-count 2 # time counts unit events 1.000420924 2,408,818 inst_retired.any # 2.1 CPI 1.000420924 5,010,111 cycles 2.001448579 2,798,407 inst_retired.any # 1.6 CPI 2.001448579 4,599,861 cycles root@kbl-ppc:~# perf stat -e cycles,instructions -I1000 --interval-count 2 # time counts unit events 1.000428555 2,769,714 cycles 1.000428555 774,462 instructions # 0.28 insn per cycle 2.001471562 3,595,904 cycles 2.001471562 1,243,703 instructions # 0.35 insn per cycle Now the second 'insn per cycle' and CPI are calculated by the counts generated in this interval. Signed-off-by: Jin Yao <[email protected]> Acked-by: Jiri Olsa <[email protected]> Tested-By: Kajol Jain <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Andi Kleen <[email protected]> Cc: Jin Yao <[email protected]> Cc: Kan Liang <[email protected]> Cc: Peter Zijlstra <[email protected]> Link: http://lore.kernel.org/lkml/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2020-04-22libbpf: Only check mode flags in get_xdp_idDavid Ahern1-0/+2
The commit in the Fixes tag changed get_xdp_id to only return prog_id if flags is 0, but there are other XDP flags than the modes - e.g., XDP_FLAGS_UPDATE_IF_NOEXIST. Since the intention was only to look at MODE flags, clear other ones before checking if flags is 0. Fixes: f07cbad29741 ("libbpf: Fix bpf_get_link_xdp_id flags handling") Signed-off-by: David Ahern <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Acked-by: Andrey Ignatov <[email protected]>
2020-04-22ipv4: Update fib_select_default to handle nexthop objectsDavid Ahern1-0/+23
A user reported [0] hitting the WARN_ON in fib_info_nh: [ 8633.839816] ------------[ cut here ]------------ [ 8633.839819] WARNING: CPU: 0 PID: 1719 at include/net/nexthop.h:251 fib_select_path+0x303/0x381 ... [ 8633.839846] RIP: 0010:fib_select_path+0x303/0x381 ... [ 8633.839848] RSP: 0018:ffffb04d407f7d00 EFLAGS: 00010286 [ 8633.839850] RAX: 0000000000000000 RBX: ffff9460b9897ee8 RCX: 00000000000000fe [ 8633.839851] RDX: 0000000000000000 RSI: 00000000ffffffff RDI: 0000000000000000 [ 8633.839852] RBP: ffff946076049850 R08: 0000000059263a83 R09: ffff9460840e4000 [ 8633.839853] R10: 0000000000000014 R11: 0000000000000000 R12: ffffb04d407f7dc0 [ 8633.839854] R13: ffffffffa4ce3240 R14: 0000000000000000 R15: ffff9460b7681f60 [ 8633.839857] FS: 00007fcac2e02700(0000) GS:ffff9460bdc00000(0000) knlGS:0000000000000000 [ 8633.839858] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 8633.839859] CR2: 00007f27beb77e28 CR3: 0000000077734000 CR4: 00000000000006f0 [ 8633.839867] Call Trace: [ 8633.839871] ip_route_output_key_hash_rcu+0x421/0x890 [ 8633.839873] ip_route_output_key_hash+0x5e/0x80 [ 8633.839876] ip_route_output_flow+0x1a/0x50 [ 8633.839878] __ip4_datagram_connect+0x154/0x310 [ 8633.839880] ip4_datagram_connect+0x28/0x40 [ 8633.839882] __sys_connect+0xd6/0x100 ... The WARN_ON is triggered in fib_select_default which is invoked when there are multiple default routes. Update the function to use fib_info_nhc and convert the nexthop checks to use fib_nh_common. Add test case that covers the affected code path. [0] https://github.com/FRRouting/frr/issues/6089 Fixes: 493ced1ac47c ("ipv4: Allow routes to use nexthop objects") Signed-off-by: David Ahern <[email protected]> Signed-off-by: David S. Miller <[email protected]>
2020-04-22objtool: Fix off-by-one in symbol_by_offset()Julien Thierry1-1/+1
Sometimes, WARN_FUNC() and other users of symbol_by_offset() will associate the first instruction of a symbol with the symbol preceding it. This is because symbol->offset + symbol->len is already outside of the symbol's range. Fixes: 2a362ecc3ec9 ("objtool: Optimize find_symbol_*() and read_symbols()") Signed-off-by: Julien Thierry <[email protected]> Reviewed-by: Miroslav Benes <[email protected]> Signed-off-by: Josh Poimboeuf <[email protected]>
2020-04-22objtool: Fix 32bit cross buildsPeter Zijlstra1-1/+1
Apparently there's people doing 64bit builds on 32bit machines. Fixes: 74b873e49d92 ("objtool: Optimize find_rela_by_dest_range()") Reported-by: [email protected] Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
2020-04-22selftests: Fix suppress test in fib_tests.shDavid Ahern1-2/+8
fib_tests is spewing errors: ... Cannot open network namespace "ns1": No such file or directory Cannot open network namespace "ns1": No such file or directory Cannot open network namespace "ns1": No such file or directory Cannot open network namespace "ns1": No such file or directory ping: connect: Network is unreachable Cannot open network namespace "ns1": No such file or directory Cannot open network namespace "ns1": No such file or directory ... Each test entry in fib_tests is supposed to do its own setup and cleanup. Right now the $IP commands in fib_suppress_test are failing because there is no ns1. Add the setup/cleanup and logging expected for each test. Fixes: ca7a03c41753 ("ipv6: do not free rt if FIB_LOOKUP_NOREF is set on suppress rule") Signed-off-by: David Ahern <[email protected]> Cc: Jason A. Donenfeld <[email protected]> Signed-off-by: David S. Miller <[email protected]>
2020-04-22perf stat: Zero all the 'ena' and 'run' array slot stats for interval modeJin Yao1-2/+4
As the code comments in perf_stat_process_counter() say, we calculate counter's data every interval, and the display code shows ps->res_stats avg value. We need to zero the stats for interval mode. But the current code only zeros the res_stats[0], it doesn't zero the res_stats[1] and res_stats[2], which are for ena and run of counter. This patch zeros the whole res_stats[] for interval mode. Fixes: 51fd2df1e882 ("perf stat: Fix interval output values") Signed-off-by: Jin Yao <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Andi Kleen <[email protected]> Cc: Jin Yao <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Kan Liang <[email protected]> Cc: Peter Zijlstra <[email protected]> Link: http://lore.kernel.org/lkml/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2020-04-22Merge tag 'linux-kselftest-5.7-rc3' of ↵Linus Torvalds10-34/+22
git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest Pull kselftest fixes from Shuah Khan: "This consists of fixes to runner scripts and individual test run-time bugs. Includes fixes to tpm2 and memfd test run-time regressions" * tag 'linux-kselftest-5.7-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: selftests/ipc: Fix test failure seen after initial test run Revert "Kernel selftests: tpm2: check for tpm support" selftests/ftrace: Add CONFIG_SAMPLE_FTRACE_DIRECT=m kconfig selftests/seccomp: allow clock_nanosleep instead of nanosleep kselftest/runner: allow to properly deliver signals to tests selftests/harness: fix spelling mistake "SIGARLM" -> "SIGALRM" selftests: Fix memfd test run-time regression selftests: vm: Fix 64-bit test builds for powerpc64le selftests: vm: Do not override definition of ARCH
2020-04-22perf script: Avoid NULL dereference on symbolIan Rogers1-1/+1
al->sym may be NULL given current if conditions and may cause a segv. Fixes: d2bedb7863e9 ("perf script: Allow --symbol to accept hexadecimal addresses") Signed-off-by: Ian Rogers <[email protected]> Acked-by: Jiri Olsa <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Stephane Eranian <[email protected]> Link: http://lore.kernel.org/lkml/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2020-04-22perf evlist: Remove duplicate headersJagadeesh Pagadala1-2/+0
Code cleanup: Remove duplicate headers which are included twice. Signed-off-by: Jagadeesh Pagadala <[email protected]> Cc: Andi Kleen <[email protected]> Cc: Jiri Olsa <[email protected]> Link: http://lore.kernel.org/lkml/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2020-04-22perf bench: Fix div-by-zero if runtime is zeroTommi Rantala3-3/+6
Fix div-by-zero if runtime is zero: $ perf bench futex hash --runtime=0 # Running 'futex/hash' benchmark: Run summary [PID 12090]: 4 threads, each operating on 1024 [private] futexes for 0 secs. Floating point exception (core dumped) Signed-off-by: Tommi Rantala <[email protected]> Acked-by: Jiri Olsa <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Darren Hart <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Link: http://lore.kernel.org/lkml/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2020-04-22perf cgroup: Avoid needless closing of unopened fdTommi Rantala1-1/+2
Do not bother with close() if fd is not valid, just to silence valgrind: $ valgrind ./perf script ==59169== Memcheck, a memory error detector ==59169== Copyright (C) 2002-2017, and GNU GPL'd, by Julian Seward et al. ==59169== Using Valgrind-3.14.0 and LibVEX; rerun with -h for copyright info ==59169== Command: ./perf script ==59169== ==59169== Warning: invalid file descriptor -1 in syscall close() ==59169== Warning: invalid file descriptor -1 in syscall close() ==59169== Warning: invalid file descriptor -1 in syscall close() ==59169== Warning: invalid file descriptor -1 in syscall close() ==59169== Warning: invalid file descriptor -1 in syscall close() ==59169== Warning: invalid file descriptor -1 in syscall close() ==59169== Warning: invalid file descriptor -1 in syscall close() ==59169== Warning: invalid file descriptor -1 in syscall close() Signed-off-by: Tommi Rantala <[email protected]> Acked-by: Jiri Olsa <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Peter Zijlstra <[email protected]> Link: http://lore.kernel.org/lkml/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2020-04-22Merge tag 'perf-core-for-mingo-5.8-20200420' of ↵Ingo Molnar72-460/+1747
git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core Pull perf/core fixes and improvements from Arnaldo Carvalho de Melo: kernel + tools/perf: Alexey Budankov: - Introduce CAP_PERFMON to kernel and user space. callchains: Adrian Hunter: - Allow using Intel PT to synthesize callchains for regular events. Kan Liang: - Stitch LBR records from multiple samples to get deeper backtraces, there are caveats, see the csets for details. perf script: Andreas Gerstmayr: - Add flamegraph.py script BPF: Jiri Olsa: - Synthesize bpf_trampoline/dispatcher ksymbol events. perf stat: Arnaldo Carvalho de Melo: - Honour --timeout for forked workloads. Stephane Eranian: - Force error in fallback on :k events, to avoid counting nothing when the user asks for kernel events but is not allowed to. perf bench: Ian Rogers: - Add event synthesis benchmark. tools api fs: Stephane Eranian: - Make xxx__mountpoint() more scalable libtraceevent: He Zhe: - Handle return value of asprintf. Signed-off-by: Arnaldo Carvalho de Melo <[email protected]> Signed-off-by: Ingo Molnar <[email protected]>
2020-04-21Merge branch 'akpm' (patches from Andrew)Linus Torvalds2-1/+3
Merge misc fixes from Andrew Morton: "15 fixes" * emailed patches from Andrew Morton <[email protected]>: tools/vm: fix cross-compile build coredump: fix null pointer dereference on coredump mm: shmem: disable interrupt when acquiring info->lock in userfaultfd_copy path shmem: fix possible deadlocks on shmlock_user_lock vmalloc: fix remap_vmalloc_range() bounds checks mm/shmem: fix build without THP mm/ksm: fix NULL pointer dereference when KSM zero page is enabled tools/build: tweak unused value workaround checkpatch: fix a typo in the regex for $allocFunctions mm, gup: return EINTR when gup is interrupted by fatal signals mm/hugetlb: fix a addressing exception caused by huge_pte_offset MAINTAINERS: add an entry for kfifo mm/userfaultfd: disable userfaultfd-wp on x86_32 slub: avoid redzone when choosing freepointer location sh: fix build error in mm/init.c
2020-04-21Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhostLinus Torvalds4-2/+5
Pull virtio fixes and cleanups from Michael Tsirkin: - Some bug fixes - Cleanup a couple of issues that surfaced meanwhile - Disable vhost on ARM with OABI for now - to be fixed fully later in the cycle or in the next release. * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (24 commits) vhost: disable for OABI virtio: drop vringh.h dependency virtio_blk: add a missing include virtio-balloon: Avoid using the word 'report' when referring to free page hinting virtio-balloon: make virtballoon_free_page_report() static vdpa: fix comment of vdpa_register_device() vdpa: make vhost, virtio depend on menu vdpa: allow a 32 bit vq alignment drm/virtio: fix up for include file changes remoteproc: pull in slab.h rpmsg: pull in slab.h virtio_input: pull in slab.h remoteproc: pull in slab.h virtio-rng: pull in slab.h virtgpu: pull in uaccess.h tools/virtio: make asm/barrier.h self contained tools/virtio: define aligned attribute virtio/test: fix up after IOTLB changes vhost: Create accessors for virtqueues private_data vdpasim: Return status in vdpasim_get_status ...
2020-04-21tools/vm: fix cross-compile buildLucas Stach1-0/+2
Commit 7ed1c1901fe5 ("tools: fix cross-compile var clobbering") moved the setup of the CC variable to tools/scripts/Makefile.include to make the behavior consistent across all the tools Makefiles. As the vm tools missed the include we end up with the wrong CC in a cross-compiling evironment. Fixes: 7ed1c1901fe5 (tools: fix cross-compile var clobbering) Signed-off-by: Lucas Stach <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Cc: Martin Kelly <[email protected]> Cc: <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Linus Torvalds <[email protected]>
2020-04-21tools/build: tweak unused value workaroundGeorge Burgess IV1-1/+1
Clang has -Wself-assign enabled by default under -Wall, which always gets -Werror'ed on this file, causing sync-compare-and-swap to be disabled by default. The generally-accepted way to spell "this value is intentionally unused," is casting it to `void`. This is accepted by both GCC and Clang with -Wall enabled: https://godbolt.org/z/qqZ9r3 Signed-off-by: George Burgess IV <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Cc: Nick Desaulniers <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Linus Torvalds <[email protected]>
2020-04-20bpf, selftests: Add test for BPF_STX BPF_B storing R10Luke Nelson1-0/+40
This patch adds a test to test_verifier that writes the lower 8 bits of R10 (aka FP) using BPF_B to an array map and reads the result back. The expected behavior is that the result should be the same as first copying R10 to R9, and then storing / loading the lower 8 bits of R9. This test catches a bug that was present in the x86-64 JIT that caused an incorrect encoding for BPF_STX BPF_B when the source operand is R10. Signed-off-by: Xi Wang <[email protected]> Signed-off-by: Luke Nelson <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-04-20bpf: Forbid XADD on spilled pointers for unprivileged usersJann Horn1-0/+1
When check_xadd() verifies an XADD operation on a pointer to a stack slot containing a spilled pointer, check_stack_read() verifies that the read, which is part of XADD, is valid. However, since the placeholder value -1 is passed as `value_regno`, check_stack_read() can only return a binary decision and can't return the type of the value that was read. The intent here is to verify whether the value read from the stack slot may be used as a SCALAR_VALUE; but since check_stack_read() doesn't check the type, and the type information is lost when check_stack_read() returns, this is not enforced, and a malicious user can abuse XADD to leak spilled kernel pointers. Fix it by letting check_stack_read() verify that the value is usable as a SCALAR_VALUE if no type information is passed to the caller. To be able to use __is_pointer_value() in check_stack_read(), move it up. Fix up the expected unprivileged error message for a BPF selftest that, until now, assumed that unprivileged users can use XADD on stack-spilled pointers. This also gives us a test for the behavior introduced in this patch for free. In theory, this could also be fixed by forbidding XADD on stack spills entirely, since XADD is a locked operation (for operations on memory with concurrency) and there can't be any concurrency on the BPF stack; but Alexei has said that he wants to keep XADD on stack slots working to avoid changes to the test suite [1]. The following BPF program demonstrates how to leak a BPF map pointer as an unprivileged user using this bug: // r7 = map_pointer BPF_LD_MAP_FD(BPF_REG_7, small_map), // r8 = launder(map_pointer) BPF_STX_MEM(BPF_DW, BPF_REG_FP, BPF_REG_7, -8), BPF_MOV64_IMM(BPF_REG_1, 0), ((struct bpf_insn) { .code = BPF_STX | BPF_DW | BPF_XADD, .dst_reg = BPF_REG_FP, .src_reg = BPF_REG_1, .off = -8 }), BPF_LDX_MEM(BPF_DW, BPF_REG_8, BPF_REG_FP, -8), // store r8 into map BPF_MOV64_REG(BPF_REG_ARG1, BPF_REG_7), BPF_MOV64_REG(BPF_REG_ARG2, BPF_REG_FP), BPF_ALU64_IMM(BPF_ADD, BPF_REG_ARG2, -4), BPF_ST_MEM(BPF_W, BPF_REG_ARG2, 0, 0), BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem), BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 1), BPF_EXIT_INSN(), BPF_STX_MEM(BPF_DW, BPF_REG_0, BPF_REG_8, 0), BPF_MOV64_IMM(BPF_REG_0, 0), BPF_EXIT_INSN() [1] https://lore.kernel.org/bpf/[email protected]/ Fixes: 17a5267067f3 ("bpf: verifier (add verifier core)") Signed-off-by: Jann Horn <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-04-20pm-graph v5.6Todd Brandt5-371/+619
sleepgraph: - force usage of python3 instead of using system default - fix bugzilla 204773 (https://bugzilla.kernel.org/show_bug.cgi?id=204773) - fix issue of platform info not being reset in -multi (logs fill up) - change -ftop call to "pm_suspend", this is one level below state_store - add -wificheck command to read out the current wifi device details - change -wifi behavior to poll /proc/net/wireless for wifi connect - add wifi reconnect time to timeline, include time in summary column - add "fail on wifi_resume" to timeline and summary when wifi fails - add a set of commands to collect data before/after suspend in the log - add "-cmdinfo" command which prints out all the data collected - check for cmd info tools at start, print found/missing in green/red - fix kernel suspend time calculation: tool used to look for start of pm_suspend_console, but the order has changed. latest kernel starts with ksys_sync, use this instead - include time spent in mem/disk in the header (same as freeze/standby) - ignore turbostat 32-bit capability warnings - print to result.txt when -skiphtml is used, just say result: pass - don't exit on SIGTSTP, it's a ctrl-Z and the tool may come back - -multi argument supports duration as well as count: hours, minutes, seconds - update the -multi status output to be more informative - -maxfail sets maximum consecutive fails before a -multi run is aborted - in -summary, ignore dmesg/ftrace/html files that are 0 size bootgraph: - force usage of python3 instead of using system default README: - add endurance testing instructions Makefile: - remove pycache on uninstall Signed-off-by: Todd Brandt <[email protected]> Signed-off-by: Rafael J. Wysocki <[email protected]>
2020-04-19Merge tag 'x86-urgent-2020-04-19' of ↵Linus Torvalds3-32/+71
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 and objtool fixes from Thomas Gleixner: "A set of fixes for x86 and objtool: objtool: - Ignore the double UD2 which is emitted in BUG() when CONFIG_UBSAN_TRAP is enabled. - Support clang non-section symbols in objtool ORC dump - Fix switch table detection in .text.unlikely - Make the BP scratch register warning more robust. x86: - Increase microcode maximum patch size for AMD to cope with new CPUs which have a larger patch size. - Fix a crash in the resource control filesystem when the removal of the default resource group is attempted. - Preserve Code and Data Prioritization enabled state accross CPU hotplug. - Update split lock cpu matching to use the new X86_MATCH macros. - Change the split lock enumeration as Intel finaly decided that the IA32_CORE_CAPABILITIES bits are not architectural contrary to what the SDM claims. !@#%$^! - Add Tremont CPU models to the split lock detection cpu match. - Add a missing static attribute to make sparse happy" * tag 'x86-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/split_lock: Add Tremont family CPU models x86/split_lock: Bits in IA32_CORE_CAPABILITIES are not architectural x86/resctrl: Preserve CDP enable over CPU hotplug x86/resctrl: Fix invalid attempt at removing the default resource group x86/split_lock: Update to use X86_MATCH_INTEL_FAM6_MODEL() x86/umip: Make umip_insns static x86/microcode/AMD: Increase microcode PATCH_MAX_SIZE objtool: Make BP scratch register warning more robust objtool: Fix switch table detection in .text.unlikely objtool: Support Clang non-section symbols in ORC generation objtool: Support Clang non-section symbols in ORC dump objtool: Fix CONFIG_UBSAN_TRAP unreachable warnings
2020-04-19Merge tag 'perf-urgent-2020-04-19' of ↵Linus Torvalds22-387/+646
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf tooling fixes and updates from Thomas Gleixner: - Fix the header line of perf stat output for '--metric-only --per-socket' - Fix the python build with clang - The usual tools UAPI header synchronization * tag 'perf-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: tools headers: Synchronize linux/bits.h with the kernel sources tools headers: Adopt verbatim copy of compiletime_assert() from kernel sources tools headers: Update x86's syscall_64.tbl with the kernel sources tools headers UAPI: Sync drm/i915_drm.h with the kernel sources tools headers UAPI: Update tools's copy of drm.h headers tools headers kvm: Sync linux/kvm.h with the kernel sources tools headers UAPI: Sync linux/fscrypt.h with the kernel sources tools include UAPI: Sync linux/vhost.h with the kernel sources tools arch x86: Sync asm/cpufeatures.h with the kernel sources tools headers UAPI: Sync linux/mman.h with the kernel tools headers UAPI: Sync sched.h with the kernel tools headers: Update linux/vdso.h and grab a copy of vdso/const.h perf stat: Fix no metric header if --per-socket and --metric-only set perf python: Check if clang supports -fno-semantic-interposition tools arch x86: Sync the msr-index.h copy with the kernel sources
2020-04-18perf hist: Add fast path for duplicate entries checkKan Liang3-1/+26
Perf checks the duplicate entries in a callchain before adding an entry. However the check is very slow especially with deeper call stack. Almost ~50% elapsed time of perf report is spent on the check when the call stack is always depth of 32. The hist_entry__cmp() is used to compare the new entry with the old entries. It will go through all the available sorts in the sort_list, and call the specific cmp of each sort, which is very slow. Actually, for most cases, there are no duplicate entries in callchain. The symbols are usually different. It's much faster to do a quick check for symbols first. Only do the full cmp when the symbols are exactly the same. The quick check is only to check symbols, not dso. Export _sort__sym_cmp. $ perf record --call-graph lbr ./tchain_edit_64 Without the patch $time perf report --stdio real 0m21.142s user 0m21.110s sys 0m0.033s With the patch $time perf report --stdio real 0m10.977s user 0m10.948s sys 0m0.027s Signed-off-by: Kan Liang <[email protected]> Acked-by: Jiri Olsa <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Alexey Budankov <[email protected]> Cc: Andi Kleen <[email protected]> Cc: Mathieu Poirier <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Pavel Gerasimov <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Ravi Bangoria <[email protected]> Cc: Stephane Eranian <[email protected]> Cc: Vitaly Slobodskoy <[email protected]> Link: http://lore.kernel.org/lkml/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2020-04-18perf c2c: Add option to enable the LBR stitching approachKan Liang2-0/+23
With the LBR stitching approach, the reconstructed LBR call stack can break the HW limitation. However, it may reconstruct invalid call stacks in some cases, e.g. exception handing such as setjmp/longjmp. Also, it may impact the processing time especially when the number of samples with stitched LBRs are huge. Add an option to enable the approach. Signed-off-by: Kan Liang <[email protected]> Reviewed-by: Andi Kleen <[email protected]> Acked-by: Jiri Olsa <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Alexey Budankov <[email protected]> Cc: Mathieu Poirier <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Pavel Gerasimov <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Ravi Bangoria <[email protected]> Cc: Stephane Eranian <[email protected]> Cc: Vitaly Slobodskoy <[email protected]> Link: http://lore.kernel.org/lkml/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2020-04-18perf top: Add option to enable the LBR stitching approachKan Liang3-0/+21
With the LBR stitching approach, the reconstructed LBR call stack can break the HW limitation. However, it may reconstruct invalid call stacks in some cases, e.g. exception handing such as setjmp/longjmp. Also, it may impact the processing time especially when the number of samples with stitched LBRs are huge. Add an option to enable the approach. The option must be used with --call-graph lbr. Signed-off-by: Kan Liang <[email protected]> Reviewed-by: Andi Kleen <[email protected]> Acked-by: Jiri Olsa <[email protected]> Tested-by: Arnaldo Carvalho de Melo <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Alexey Budankov <[email protected]> Cc: Mathieu Poirier <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Pavel Gerasimov <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Ravi Bangoria <[email protected]> Cc: Stephane Eranian <[email protected]> Cc: Vitaly Slobodskoy <[email protected]> Link: http://lore.kernel.org/lkml/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2020-04-18perf script: Add option to enable the LBR stitching approachKan Liang2-0/+23
With the LBR stitching approach, the reconstructed LBR call stack can break the HW limitation. However, it may reconstruct invalid call stacks in some cases, e.g. exception handing such as setjmp/longjmp. Also, it may impact the processing time especially when the number of samples with stitched LBRs are huge. Add an option to enable the approach. Committer testing: Using the same perf.data as with the latest cset committer testing section: $ perf script --stitch-lbr <SNIP> tchain_edit 11131 15164.984292: 437491 cycles:u: 401106 f43+0x0 (/wb/tchain_edit) 40114c f42+0x18 (/wb/tchain_edit) 401172 f41+0xe (/wb/tchain_edit) 401194 f40+0x0 (/wb/tchain_edit) 40119b f39+0x0 (/wb/tchain_edit) 4011a2 f38+0x0 (/wb/tchain_edit) 4011a9 f37+0x0 (/wb/tchain_edit) 4011b0 f36+0x0 (/wb/tchain_edit) 4011b7 f35+0x0 (/wb/tchain_edit) 4011be f34+0x0 (/wb/tchain_edit) 4011c5 f33+0x0 (/wb/tchain_edit) 4011cc f32+0x0 (/wb/tchain_edit) 401207 f31+0x34 (/wb/tchain_edit) 401212 f30+0x0 (/wb/tchain_edit) 401219 f29+0x0 (/wb/tchain_edit) 401220 f28+0x0 (/wb/tchain_edit) 401227 f27+0x0 (/wb/tchain_edit) 40122e f26+0x0 (/wb/tchain_edit) 401235 f25+0x0 (/wb/tchain_edit) 40123c f24+0x0 (/wb/tchain_edit) 401243 f23+0x0 (/wb/tchain_edit) 40124a f22+0x0 (/wb/tchain_edit) 401251 f21+0x0 (/wb/tchain_edit) 401258 f20+0x0 (/wb/tchain_edit) 40125f f19+0x0 (/wb/tchain_edit) 401266 f18+0x0 (/wb/tchain_edit) 40126d f17+0x0 (/wb/tchain_edit) 401274 f16+0x0 (/wb/tchain_edit) 40127b f15+0x0 (/wb/tchain_edit) 401282 f14+0x0 (/wb/tchain_edit) 401289 f13+0x0 (/wb/tchain_edit) 401290 f12+0x0 (/wb/tchain_edit) 401297 f11+0x0 (/wb/tchain_edit) 40129e f10+0x0 (/wb/tchain_edit) 4012a5 f9+0x0 (/wb/tchain_edit) 4012ac f8+0x0 (/wb/tchain_edit) 4012b3 f7+0x0 (/wb/tchain_edit) 4012ba f6+0x0 (/wb/tchain_edit) 4012c1 f5+0x0 (/wb/tchain_edit) 4012c8 f4+0x0 (/wb/tchain_edit) 4012cf f3+0x0 (/wb/tchain_edit) 4012d6 f2+0x0 (/wb/tchain_edit) 4012dd f1+0x0 (/wb/tchain_edit) 4012e4 main+0x0 (/wb/tchain_edit) 7f41a5016f41 __libc_start_main+0xf1 (/usr/lib64/libc-2.29.so) <SNIP> $ Signed-off-by: Kan Liang <[email protected]> Reviewed-by: Andi Kleen <[email protected]> Acked-by: Jiri Olsa <[email protected]> Tested-by: Arnaldo Carvalho de Melo <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Alexey Budankov <[email protected]> Cc: Mathieu Poirier <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Pavel Gerasimov <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Ravi Bangoria <[email protected]> Cc: Stephane Eranian <[email protected]> Cc: Vitaly Slobodskoy <[email protected]> Link: http://lore.kernel.org/lkml/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2020-04-18perf report: Add option to enable the LBR stitching approachKan Liang2-0/+23
With the LBR stitching approach, the reconstructed LBR call stack can break the HW limitation. However, it may reconstruct invalid call stacks in some cases, e.g. exception handing such as setjmp/longjmp. Also, it may impact the processing time especially when the number of samples with stitched LBRs are huge. Add an option to enable the approach. # To display the perf.data header info, please use # --header/--header-only options. # # # Total Lost Samples: 0 # # Samples: 6K of event 'cycles' # Event count (approx.): 6492797701 # # Children Self Command Shared Object Symbol # ........ ........ ............... .................. # ................................. # 99.99% 99.99% tchain_edit tchain_edit [.] f43 | ---main f1 f2 f3 f4 f5 f6 f7 f8 f9 f10 f11 f12 f13 f14 f15 f16 f17 f18 f19 f20 f21 f22 f23 f24 f25 f26 f27 f28 f29 f30 f31 | --99.65%--f32 f33 f34 f35 f36 f37 f38 f39 f40 f41 f42 f43 Committer testing: $ perf record --call-graph lbr /wb/tchain_edit [ perf record: Woken up 23 times to write data ] [ perf record: Captured and wrote 5.578 MB perf.data (6839 samples) ] $ perf report --header-only | egrep 'cpu(desc|.*capabilities)' # cpudesc : Intel(R) Core(TM) i5-7500 CPU @ 3.40GHz # cpu pmu capabilities: branches=32, max_precise=3, pmu_name=skylake $ Before: $ perf report --no-children --stdio # To display the perf.data header info, please use --header/--header-only options. # # # Total Lost Samples: 0 # # Samples: 6K of event 'cycles:u' # Event count (approx.): 6459523879 # # Overhead Command Shared Object Symbol # ........ ........... ................ ....................... # 99.95% tchain_edit tchain_edit [.] f43 | --99.92%--f43 f42 f41 f40 f39 f38 f37 f36 f35 f34 f33 f32 f31 f30 f29 f28 f27 f26 f25 f24 f23 f22 f21 f20 f19 f18 f17 f16 f15 f14 f13 f12 f11 0.03% tchain_edit tchain_edit [.] f42 0.01% tchain_edit tchain_edit [.] f41 0.00% tchain_edit tchain_edit [.] f31 0.00% tchain_edit ld-2.29.so [.] _dl_relocate_object 0.00% tchain_edit ld-2.29.so [.] memmove 0.00% tchain_edit [unknown] [k] 0xffffffff93a00b17 After: $ perf report --stitch-lbr --no-children --stdio # To display the perf.data header info, please use --header/--header-only options. # # # Total Lost Samples: 0 # # Samples: 6K of event 'cycles:u' # Event count (approx.): 6459496645 # # Overhead Command Shared Object Symbol # ........ ........... ................ ........................ # 99.97% tchain_edit tchain_edit [.] f43 | --99.93%--f43 f42 f41 f40 f39 f38 f37 f36 f35 f34 f33 f32 f31 f30 f29 f28 f27 f26 f25 f24 f23 f22 f21 f20 f19 f18 f17 f16 f15 f14 f13 f12 f11 f10 f9 f8 f7 f6 f5 f4 f3 f2 f1 main __libc_start_main 0.02% tchain_edit [unknown] [k] 0xffffffff93a00b17 0.01% tchain_edit tchain_edit [.] f31 0.00% tchain_edit ld-2.29.so [.] _dl_important_hwcaps Signed-off-by: Kan Liang <[email protected]> Reviewed-by: Andi Kleen <[email protected]> Acked-by: Jiri Olsa <[email protected]> Tested-by: Arnaldo Carvalho de Melo <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Alexey Budankov <[email protected]> Cc: Mathieu Poirier <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Pavel Gerasimov <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Ravi Bangoria <[email protected]> Cc: Stephane Eranian <[email protected]> Cc: Vitaly Slobodskoy <[email protected]> Link: http://lore.kernel.org/lkml/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2020-04-18perf callchain: Stitch LBR call stackKan Liang6-28/+188
In LBR call stack mode, the depth of reconstructed LBR call stack limits to the number of LBR registers. For example, on skylake, the depth of reconstructed LBR call stack is always <= 32. # To display the perf.data header info, please use # --header/--header-only options. # # # Total Lost Samples: 0 # # Samples: 6K of event 'cycles' # Event count (approx.): 6487119731 # # Children Self Command Shared Object Symbol # ........ ........ ............... .................. # ................................ 99.97% 99.97% tchain_edit tchain_edit [.] f43 | --99.64%--f11 f12 f13 f14 f15 f16 f17 f18 f19 f20 f21 f22 f23 f24 f25 f26 f27 f28 f29 f30 f31 f32 f33 f34 f35 f36 f37 f38 f39 f40 f41 f42 f43 For a call stack which is deeper than LBR limit, HW will overwrite the LBR register with oldest branch. Only partial call stacks can be reconstructed. However, the overwritten LBRs may still be retrieved from previous sample. At that moment, HW hasn't overwritten the LBR registers yet. Perf tools can stitch those overwritten LBRs on current call stacks to get a more complete call stack. To determine if LBRs can be stitched, perf tools need to compare current sample with previous sample. - They should have identical LBR records (Same from, to and flags values, and the same physical index of LBR registers). - The searching starts from the base-of-stack of current sample. Once perf determines to stitch the previous LBRs, the corresponding LBR cursor nodes will be copied to 'lists'. The 'lists' is to track the LBR cursor nodes which are going to be stitched. When the stitching is over, the nodes will not be freed immediately. They will be moved to 'free_lists'. Next stitching may reuse the space. Both 'lists' and 'free_lists' will be freed when all samples are processed. Committer notes: Fix the intel-pt.c initialization of the union with 'struct branch_flags', that breaks the build with its unnamed union on older gcc versions. Uninline thread__free_stitch_list(), as it grew big and started dragging includes to thread.h, so move it to thread.c where what it needs in terms of headers are already there. This fixes the build in several systems such as debian:experimental when cross building to the MIPS32 architecture, i.e. in the other cases what was needed was being included by sheer luck. In file included from builtin-sched.c:11: util/thread.h: In function 'thread__free_stitch_list': util/thread.h:169:3: error: implicit declaration of function 'free' [-Werror=implicit-function-declaration] 169 | free(pos); | ^~~~ util/thread.h:169:3: error: incompatible implicit declaration of built-in function 'free' [-Werror] util/thread.h:19:1: note: include '<stdlib.h>' or provide a declaration of 'free' 18 | #include "callchain.h" +++ |+#include <stdlib.h> 19 | util/thread.h:174:3: error: incompatible implicit declaration of built-in function 'free' [-Werror] 174 | free(pos); | ^~~~ util/thread.h:174:3: note: include '<stdlib.h>' or provide a declaration of 'free' Signed-off-by: Kan Liang <[email protected]> Reviewed-by: Andi Kleen <[email protected]> Acked-by: Jiri Olsa <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Alexey Budankov <[email protected]> Cc: Mathieu Poirier <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Pavel Gerasimov <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Ravi Bangoria <[email protected]> Cc: Stephane Eranian <[email protected]> Cc: Vitaly Slobodskoy <[email protected]> Link: http://lore.kernel.org/lkml/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2020-04-18perf callchain: Save previous cursor nodes for LBR stitching approachKan Liang3-4/+83
The cursor nodes which generates from sample are eventually added into callchain. To avoid generating cursor nodes from previous samples again, the previous cursor nodes are also saved for LBR stitching approach. Some option, e.g. hide-unresolved, may hide some LBRs. Add a variable 'valid' in struct callchain_cursor_node to indicate this case. The LBR stitching approach will only append the valid cursor nodes from previous samples later. Signed-off-by: Kan Liang <[email protected]> Reviewed-by: Andi Kleen <[email protected]> Acked-by: Jiri Olsa <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Alexey Budankov <[email protected]> Cc: Mathieu Poirier <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Pavel Gerasimov <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Ravi Bangoria <[email protected]> Cc: Stephane Eranian <[email protected]> Cc: Vitaly Slobodskoy <[email protected]> Link: http://lore.kernel.org/lkml/[email protected] [ Use zfree() instead of open coded equivalent, and use it when freeing members of structs ] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2020-04-18perf thread: Save previous sample for LBR stitching approachKan Liang3-0/+36
To retrieve the overwritten LBRs from previous sample for LBR stitching approach, perf has to save the previous sample. Only allocate the struct lbr_stitch once, when LBR stitching approach is enabled and kernel supports hw_idx. Signed-off-by: Kan Liang <[email protected]> Reviewed-by: Andi Kleen <[email protected]> Acked-by: Jiri Olsa <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Alexey Budankov <[email protected]> Cc: Mathieu Poirier <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Pavel Gerasimov <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Ravi Bangoria <[email protected]> Cc: Stephane Eranian <[email protected]> Cc: Vitaly Slobodskoy <[email protected]> Link: http://lore.kernel.org/lkml/[email protected] [ Use zalloc()/zfree() for thread->lbr_stitch ] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2020-04-18perf thread: Add a knob for LBR stitch approachKan Liang2-0/+4
The LBR stitch approach should be disabled by default. Because - The stitching approach base on LBR call stack technology. The known limitations of LBR call stack technology still apply to the approach, e.g. Exception handing such as setjmp/longjmp will have calls/returns not match. - This approach is not foolproof. There can be cases where it creates incorrect call stacks from incorrect matches. There is no attempt to validate any matches in another way. The 'lbr_stitch_enable' is used to indicate whether enable LBR stitch approach, which is disabled by default. The following patch will introduce a new option for each tools to enable the LBR stitch approach. Signed-off-by: Kan Liang <[email protected]> Reviewed-by: Andi Kleen <[email protected]> Acked-by: Jiri Olsa <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Alexey Budankov <[email protected]> Cc: Mathieu Poirier <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Pavel Gerasimov <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Ravi Bangoria <[email protected]> Cc: Stephane Eranian <[email protected]> Cc: Vitaly Slobodskoy <[email protected]> Link: http://lore.kernel.org/lkml/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2020-04-18perf machine: Factor out lbr_callchain_add_lbr_ip()Kan Liang1-70/+73
Both caller and callee needs to add ip from LBR to callchain. Factor out lbr_callchain_add_lbr_ip() to improve code readability. Signed-off-by: Kan Liang <[email protected]> Reviewed-by: Andi Kleen <[email protected]> Acked-by: Jiri Olsa <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Alexey Budankov <[email protected]> Cc: Mathieu Poirier <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Pavel Gerasimov <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Ravi Bangoria <[email protected]> Cc: Stephane Eranian <[email protected]> Cc: Vitaly Slobodskoy <[email protected]> Link: http://lore.kernel.org/lkml/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2020-04-18perf machine: Factor out lbr_callchain_add_kernel_ip()Kan Liang1-22/+45
Both caller and callee needs to add kernel ip to callchain. Factor out lbr_callchain_add_kernel_ip() to improve code readability. Signed-off-by: Kan Liang <[email protected]> Reviewed-by: Andi Kleen <[email protected]> Acked-by: Jiri Olsa <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Alexey Budankov <[email protected]> Cc: Mathieu Poirier <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Pavel Gerasimov <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Ravi Bangoria <[email protected]> Cc: Stephane Eranian <[email protected]> Cc: Vitaly Slobodskoy <[email protected]> Link: http://lore.kernel.org/lkml/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2020-04-18perf machine: Refine the function for LBR call stack reconstructionKan Liang1-35/+76
LBR only collect the user call stack. To reconstruct a call stack, both kernel call stack and user call stack are required. The function resolve_lbr_callchain_sample() mix the kernel call stack and user call stack. Now, with the help of HW idx, perf tool can reconstruct a more complete call stack by adding some user call stack from previous sample. However, current implementation is hard to be extended to support it. Current code path for resolve_lbr_callchain_sample() for (j = 0; j < mix_chain_nr; j++) { if (ORDER_CALLEE) { if (kernel callchain) Fill callchain info else if (LBR callchain) Fill callchain info } else { if (LBR callchain) Fill callchain info else if (kernel callchain) Fill callchain info } add_callchain_ip(); } With the patch, if (ORDER_CALLEE) { for (j = 0; j < NUM of kernel callchain) { Fill callchain info add_callchain_ip(); } for (; j < mix_chain_nr) { Fill callchain info add_callchain_ip(); } } else { for (; j < NUM of LBR callchain) { Fill callchain info add_callchain_ip(); } for (j = 0; j < mix_chain_nr) { Fill callchain info add_callchain_ip(); } } No functional changes. Signed-off-by: Kan Liang <[email protected]> Reviewed-by: Andi Kleen <[email protected]> Acked-by: Jiri Olsa <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Alexey Budankov <[email protected]> Cc: Mathieu Poirier <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Pavel Gerasimov <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Ravi Bangoria <[email protected]> Cc: Stephane Eranian <[email protected]> Cc: Vitaly Slobodskoy <[email protected]> Link: http://lore.kernel.org/lkml/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2020-04-18perf machine: Remove the indent in resolve_lbr_callchain_sampleKan Liang1-60/+63
The indent is unnecessary in resolve_lbr_callchain_sample. Removing it will make the following patch simpler. Current code path for resolve_lbr_callchain_sample() /* LBR only affects the user callchain */ if (i != chain_nr) { body of the function .... return 1; } return 0; With the patch, /* LBR only affects the user callchain */ if (i == chain_nr) return 0; body of the function ... return 1; No functional changes. Signed-off-by: Kan Liang <[email protected]> Reviewed-by: Andi Kleen <[email protected]> Acked-by: Jiri Olsa <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Alexey Budankov <[email protected]> Cc: Mathieu Poirier <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Pavel Gerasimov <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Ravi Bangoria <[email protected]> Cc: Stephane Eranian <[email protected]> Cc: Vitaly Slobodskoy <[email protected]> Link: http://lore.kernel.org/lkml/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2020-04-18perf header: Support CPU PMU capabilitiesKan Liang4-0/+128
To stitch LBR call stack, the max LBR information is required. So the CPU PMU capabilities information has to be stored in perf header. Add a new feature HEADER_CPU_PMU_CAPS for CPU PMU capabilities. Retrieve all CPU PMU capabilities, not just max LBR information. Add variable max_branches to facilitate future usage. Committer testing: # ls -la /sys/devices/cpu/caps/ total 0 drwxr-xr-x. 2 root root 0 Apr 17 10:53 . drwxr-xr-x. 6 root root 0 Apr 17 07:02 .. -r--r--r--. 1 root root 4096 Apr 17 10:53 max_precise # # cat /sys/devices/cpu/caps/max_precise 0 # perf record sleep 1 [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.033 MB perf.data (7 samples) ] # # perf report --header-only | egrep 'cpu(desc|.*capabilities)' # cpudesc : AMD Ryzen 5 3600X 6-Core Processor # cpu pmu capabilities: max_precise=0 # And then on an Intel machine: $ ls -la /sys/devices/cpu/caps/ total 0 drwxr-xr-x. 2 root root 0 Apr 17 10:51 . drwxr-xr-x. 6 root root 0 Apr 17 10:04 .. -r--r--r--. 1 root root 4096 Apr 17 11:37 branches -r--r--r--. 1 root root 4096 Apr 17 10:51 max_precise -r--r--r--. 1 root root 4096 Apr 17 11:37 pmu_name $ cat /sys/devices/cpu/caps/max_precise 3 $ cat /sys/devices/cpu/caps/branches 32 $ cat /sys/devices/cpu/caps/pmu_name skylake $ perf record sleep 1 [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.001 MB perf.data (8 samples) ] $ perf report --header-only | egrep 'cpu(desc|.*capabilities)' # cpudesc : Intel(R) Core(TM) i5-7500 CPU @ 3.40GHz # cpu pmu capabilities: branches=32, max_precise=3, pmu_name=skylake $ Signed-off-by: Kan Liang <[email protected]> Reviewed-by: Andi Kleen <[email protected]> Acked-by: Jiri Olsa <[email protected]> Tested-by: Arnaldo Carvalho de Melo <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Alexey Budankov <[email protected]> Cc: Mathieu Poirier <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Pavel Gerasimov <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Ravi Bangoria <[email protected]> Cc: Stephane Eranian <[email protected]> Cc: Vitaly Slobodskoy <[email protected]> Link: http://lore.kernel.org/lkml/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2020-04-18perf parser: Add support to specify rXXX event with pmuJiri Olsa4-1/+31
The current rXXXX event specification creates event under PERF_TYPE_RAW pmu type. This change allows to use rXXXX within pmu syntax, so it's type is used via the following syntax: -e 'cpu/r3c/' -e 'cpum_cf/r0/' The XXXX number goes directly to perf_event_attr::config the same way as in '-e rXXXX' event. The perf_event_attr::type is filled with pmu type. Committer testing: So, lets see what goes in perf_event_attr::config for, say, the 'instructions' PERF_TYPE_HARDWARE (0) event, first we should look at how to encode this event as a PERF_TYPE_RAW event for this specific CPU, an AMD Ryzen 5: # cat /sys/devices/cpu/events/instructions event=0xc0 # Then try with it _and_ the instruction, just to see that they are close enough: # perf stat -e rc0,instructions sleep 1 Performance counter stats for 'sleep 1': 919,794 rc0 919,898 instructions 1.000754579 seconds time elapsed 0.000715000 seconds user 0.000000000 seconds sys # Now we should try, before this patch, the PMU event encoding: # perf stat -e cpu/rc0/ sleep 1 event syntax error: 'cpu/rc0/' \___ unknown term valid terms: event,edge,inv,umask,cmask,config,config1,config2,name,period,percore # Now with this patch, the three ways of specifying the 'instructions' CPU counter are accepted: # perf stat -e cpu/rc0/,rc0,instructions sleep 1 Performance counter stats for 'sleep 1': 892,948 cpu/rc0/ 893,052 rc0 893,156 instructions 1.000931819 seconds time elapsed 0.000916000 seconds user 0.000000000 seconds sys # Requested-by: Thomas Richter <[email protected]> Signed-off-by: Jiri Olsa <[email protected]> Tested-by: Arnaldo Carvalho de Melo <[email protected]> Tested-by: Thomas Richter <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Michael Petlan <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Sumanth Korikkar <[email protected]> Cc: Vasily Gorbik <[email protected]> Link: http://lore.kernel.org/lkml/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2020-04-18perf doc: allow ASCIIDOC_EXTRA to be an argumentIan Rogers1-2/+2
This will allow parent makefiles to pass values to asciidoc. Signed-off-by: Ian Rogers <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Alexei Starovoitov <[email protected]> Cc: Alexey Budankov <[email protected]> Cc: Andi Kleen <[email protected]> Cc: Andrii Nakryiko <[email protected]> Cc: Daniel Borkmann <[email protected]> Cc: Florian Fainelli <[email protected]> Cc: Greg Kroah-Hartman <[email protected]> Cc: Igor Lubashev <[email protected]> Cc: Jin Yao <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Jiwei Sun <[email protected]> Cc: John Garry <[email protected]> Cc: Kan Liang <[email protected]> Cc: Leo Yan <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Martin KaFai Lau <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Stephane Eranian <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Yonghong Song <[email protected]> Cc: [email protected] Cc: [email protected] Cc: yuzhoujian <[email protected]> Link: http://lore.kernel.org/lkml/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2020-04-18perf pmu: Add support for PMU capabilitiesKan Liang2-0/+91
The PMU capabilities information, which is located at /sys/bus/event_source/devices/<dev>/caps, is required by perf tool. For example, the max LBR information is required to stitch LBR call stack. Add perf_pmu__caps_parse() to parse the PMU capabilities information. The information is stored in a list. The following patch will store the capabilities information in perf header. Committer notes: Here's an example of such directories and its files in an i5 7th gen machine: [root@seventh ~]# ls -lad /sys/bus/event_source/devices/*/caps drwxr-xr-x. 2 root root 0 Apr 14 13:33 /sys/bus/event_source/devices/cpu/caps drwxr-xr-x. 2 root root 0 Apr 14 13:33 /sys/bus/event_source/devices/intel_pt/caps [root@seventh ~]# ls -la /sys/bus/event_source/devices/intel_pt/caps total 0 drwxr-xr-x. 2 root root 0 Apr 14 13:33 . drwxr-xr-x. 5 root root 0 Apr 14 13:12 .. -r--r--r--. 1 root root 4096 Apr 16 13:10 cr3_filtering -r--r--r--. 1 root root 4096 Apr 16 11:42 cycle_thresholds -r--r--r--. 1 root root 4096 Apr 16 13:10 ip_filtering -r--r--r--. 1 root root 4096 Apr 16 13:10 max_subleaf -r--r--r--. 1 root root 4096 Apr 14 13:33 mtc -r--r--r--. 1 root root 4096 Apr 14 13:33 mtc_periods -r--r--r--. 1 root root 4096 Apr 16 13:10 num_address_ranges -r--r--r--. 1 root root 4096 Apr 16 13:10 output_subsys -r--r--r--. 1 root root 4096 Apr 16 13:10 payloads_lip -r--r--r--. 1 root root 4096 Apr 16 13:10 power_event_trace -r--r--r--. 1 root root 4096 Apr 14 13:33 psb_cyc -r--r--r--. 1 root root 4096 Apr 14 13:33 psb_periods -r--r--r--. 1 root root 4096 Apr 16 13:10 ptwrite -r--r--r--. 1 root root 4096 Apr 16 13:10 single_range_output -r--r--r--. 1 root root 4096 Apr 16 12:03 topa_multiple_entries -r--r--r--. 1 root root 4096 Apr 16 13:10 topa_output [root@seventh ~]# cat /sys/bus/event_source/devices/intel_pt/caps/topa_output 1 [root@seventh ~]# cat /sys/bus/event_source/devices/intel_pt/caps/topa_multiple_entries 1 [root@seventh ~]# cat /sys/bus/event_source/devices/intel_pt/caps/mtc 1 [root@seventh ~]# cat /sys/bus/event_source/devices/intel_pt/caps/power_event_trace 0 [root@seventh ~]# [root@seventh ~]# ls -la /sys/bus/event_source/devices/cpu/caps/ total 0 drwxr-xr-x. 2 root root 0 Apr 14 13:33 . drwxr-xr-x. 6 root root 0 Apr 14 13:12 .. -r--r--r--. 1 root root 4096 Apr 16 13:10 branches -r--r--r--. 1 root root 4096 Apr 14 13:33 max_precise -r--r--r--. 1 root root 4096 Apr 16 13:10 pmu_name [root@seventh ~]# cat /sys/bus/event_source/devices/cpu/caps/max_precise 3 [root@seventh ~]# cat /sys/bus/event_source/devices/cpu/caps/branches 32 [root@seventh ~]# cat /sys/bus/event_source/devices/cpu/caps/pmu_name skylake [root@seventh ~]# Wow, first time I've heard about /sys/bus/event_source/devices/cpu/caps/max_precise, I think I'll use it! :-) Signed-off-by: Kan Liang <[email protected]> Reviewed-by: Andi Kleen <[email protected]> Acked-by: Jiri Olsa <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Alexey Budankov <[email protected]> Cc: Mathieu Poirier <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Pavel Gerasimov <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Ravi Bangoria <[email protected]> Cc: Stephane Eranian <[email protected]> Cc: Vitaly Slobodskoy <[email protected]> Link: http://lore.kernel.org/lkml/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2020-04-18tools lib traceevent: Take care of return value of asprintfHe Zhe1-10/+19
According to the API, if memory allocation wasn't possible, or some other error occurs, asprintf will return -1, and the contents of strp below are undefined. int asprintf(char **strp, const char *fmt, ...); This patch takes care of return value of asprintf to make it less error prone and prevent the following build warning. ignoring return value of ‘asprintf’, declared with attribute warn_unused_result [-Wunused-result] Signed-off-by: He Zhe <[email protected]> Reviewed-by: Steven Rostedt (VMware) <[email protected]> Cc: Tzvetomir Stoyanov <[email protected]> Cc: [email protected] Link: http://lore.kernel.org/lkml/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>