- 06 Aug, 2015 3 commits
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Wang Nan authored
Commit e1abf2cc ("bpf: Fix the build on BPF_SYSCALL=y && !CONFIG_TRACING kernels, make it more configurable") updated the building condition of bpf_trace.o from CONFIG_BPF_SYSCALL to CONFIG_BPF_EVENTS, but the corresponding #ifdef controller in trace_events.h for trace_call_bpf() was not changed. Which, in theory, is incorrect. With current Kconfigs, we can create a .config with CONFIG_BPF_SYSCALL=y and CONFIG_BPF_EVENTS=n by unselecting CONFIG_KPROBE_EVENT and selecting CONFIG_BPF_SYSCALL. With these options, trace_call_bpf() will be defined as an extern function, but if anyone calls it a symbol missing error will be triggered since bpf_trace.o was not built. This patch changes the #ifdef controller for trace_call_bpf() from CONFIG_BPF_SYSCALL to CONFIG_BPF_EVENTS. I'll show its correctness: Before this patch: BPF_SYSCALL BPF_EVENTS trace_call_bpf bpf_trace.o y y normal compiled n n inline not compiled y n normal not compiled (incorrect) n y impossible (BPF_EVENTS depends on BPF_SYSCALL) After this patch: BPF_SYSCALL BPF_EVENTS trace_call_bpf bpf_trace.o y y normal compiled n n inline not compiled y n inline not compiled (fixed) n y impossible (BPF_EVENTS depends on BPF_SYSCALL) So this patch doesn't break anything. QED. Signed-off-by:
Wang Nan <wangnan0@huawei.com> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David Ahern <dsahern@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kaixu Xia <xiakaixu@huawei.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1435716878-189507-2-git-send-email-wangnan0@huawei.comSigned-off-by:
Arnaldo Carvalho de Melo <acme@redhat.com>
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Milian Wolff authored
It is cumbersome to manually calculate the total time spent in a given syscall by multiplying the average value with the number of calls. Instead, we now do this directly inside perf trace. Note that this is also done by 'strace', which even adds a column with relative numbers - something we could do in the future. Example: perf trace -s find /some/folder > /dev/null Summary of events: find (19976), 700123 events, 100.0%, 0.000 msec syscall calls total min avg max stddev (msec) (msec) (msec) (msec) (%) --------------- -------- --------- --------- --------- --------- ------ read 4 0.006 0.001 0.002 0.003 27.42% write 8046 9.617 0.001 0.001 0.035 0.56% open 34196 40.384 0.001 0.001 0.071 0.30% close 68375 57.104 0.001 0.001 0.076 0.25% stat 4 0.004 0.001 0.001 0.001 3.14% fstat 34189 27.518 0.001 0.001 0.060 0.34% mmap 13 0.029 0.001 0.002 0.003 10.74% mprotect 6 0.018 0.002 0.003 0.005 17.04% munmap 3 0.014 0.003 0.005 0.006 24.87% brk 87 0.490 0.001 0.006 0.016 6.50% ioctl 3 0.004 0.001 0.001 0.003 36.39% access 1 0.004 0.004 0.004 0.004 0.00% uname 1 0.001 0.001 0.001 0.001 0.00% getdents 68393 143.600 0.001 0.002 0.187 0.95% fchdir 68371 56.980 0.001 0.001 0.111 0.39% arch_prctl 1 0.001 0.001 0.001 0.001 0.00% openat 34184 41.737 0.001 0.001 0.102 0.41% newfstatat 34184 41.180 0.001 0.001 0.064 0.34% Signed-off-by:Milian Wolff <milian.wolff@kdab.com> Tested-by:
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Ingo Molnar authored
Merge tag 'perf-core-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo: New features: - Deref sys_enter pointer args with contents from probe:vfs_getname, showing pathnames instead of pointers in many syscalls in 'perf trace'. (Arnaldo Carvalho de Melo) - Make 'perf trace' write to stderr by default, just like 'strace'. (Milian Woff) Infrastructure changes: - color_vfprintf() fixes. (Andi Kleen, Jiri Olsa) - Allow enabling/disabling PERF_SAMPLE_TIME per event. (Kan Liang) - Fix build errors with mipsel-linux-uclibc compiler. (Petri Gynther) Signed-off-by:
Ingo Molnar <mingo@kernel.org>
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- 05 Aug, 2015 11 commits
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Petri Gynther authored
linux/tools$ make ARCH=mips CROSS_COMPILE=mipsel-linux- perf ... config/Makefile:256: *** No gnu/libc-version.h found, please install glibc-dev[el]. Stop. make[1]: *** [all] Error 2 make: *** [perf] Error 2 ... In file included from builtin-sched.c:13:0: util/cloexec.h:8:12: error: redundant redeclaration of ‘sched_getcpu’ [-Werror=redundant-decls] extern int sched_getcpu(void) __THROW; mipsel-buildroot-linux-uclibc/sysroot/usr/include/bits/sched.h:88:12: note: previous declaration of ‘sched_getcpu’ was here extern int sched_getcpu (void) __THROW; uclibc info: sysroot/usr/include/bits/uClibc_config.h __UCLIBC_MAJOR__ 0 __UCLIBC_MINOR__ 9 __UCLIBC_SUBLEVEL__ 33 sysroot/usr/include/features.h __UCLIBC__ 1 __GLIBC__ 2 __GLIBC_MINOR__ 2 Signed-off-by:
Petri Gynther <pgynther@google.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1438735081-24131-1-git-send-email-pgynther@google.comSigned-off-by:
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Milian Wolff authored
Without this patch, it is cumbersome to read the trace output but ignoring the normal, potentially verbose, output of the debuggee. One common example is doing something like the following: perf trace -s find /tmp > /dev/null Without this patch, the trace summary will be lost. Now, it will still be printed at the end. This behavior is also applied by strace. Cc: Milian Wolff <milian.wolff@kdab.com> Cc: David Ahern <dsahern@gmail.com> Link: http://lkml.kernel.org/n/tip-tqnks6y2cnvm5f9g2dsfr7zl@git.kernel.orgSigned-off-by:
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Andi Kleen authored
color_vprintf was including the length of the invisible escape sequences in its return argument. Don't include them to make the return value usable for indentation calculations. v2: Add comment, rebase Signed-off-by:
Andi Kleen <ak@linux.intel.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/r/1438649408-20807-3-git-send-email-andi@firstfloor.orgSigned-off-by:
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Jiri Olsa authored
Seems like it's always '\n' through color_fprintf_ln, which is not used at all, removing.. ;-) Signed-off-by:
Jiri Olsa <jolsa@kernel.org> Cc: Andi Kleen <ak@linux.intel.com> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/r/1438649408-20807-2-git-send-email-andi@firstfloor.orgSigned-off-by:
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Kan Liang authored
Pass global callchain_param into parse_callchain_record_opt and perf_evsel__config_callgraph as parameter. So we can reuse these functions to parse/config local param for callchain. Signed-off-by:
Kan Liang <kan.liang@intel.com> Acked-by:
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Kan Liang authored
This patchkit adds the ability to turn off time stamps per event. One usaful case for partial time is to work with per-event callgraph to enable "PEBS threshold > 1" (https://lkml.org/lkml/2015/5/10/196), which can significantly reduce the sampling overhead. The event samples with time stamps off will not be ordered. Signed-off-by:
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Arnaldo Carvalho de Melo authored
Those were covered and tested in this cset: access, chdir, chmod, chown, chroot, creat, getxattr, inotify_add_watch, lchown, lgetxattr, listxattr, lsetxattr, mkdir, mkdirat, mknod, rmdir, faccessat, newfstatat, openat, readlink, readlinkat, removexattr, setxattr, statfs, swapon, swapoff, truncate, unlinkat, utime, utimes, utimensat. E.g.: # trace -e statfs,access,mkdir mkdir /tmp/bla 0.285 (0.020 ms): mkdir/2799 access(filename: /etc/ld.so.preload, mode: R ) = -1 ENOENT No such file or directory 1.070 (0.032 ms): mkdir/2799 statfs(pathname: /sys/fs/selinux, buf: 0x7ffeafbdc930) = 0 1.087 (0.013 ms): mkdir/2799 statfs(pathname: /sys/fs/selinux, buf: 0x7ffeafbdc820) = 0 1.189 (0.014 ms): mkdir/2799 access(filename: /etc/selinux/config ) = 0 1.905 (0.610 ms): mkdir/2799 mkdir(pathname: /tmp/bla, mode: 511 ) = 0 # Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Borislav Petkov <bp@suse.de> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Milian Wolff <mail@milianw.de> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/n/tip-wbqtnlktquun3wtpjdz3okul@git.kernel.orgSigned-off-by:
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Arnaldo Carvalho de Melo authored
To work like strace and dereference syscall pointer args we need to insert probes (or tracepoints) right after we copy those bytes from userspace. Since we're formatting the syscall args at raw_syscalls:sys_enter time, we need to have a formatter that just stores the position where, later, when we get the probe:vfs_getname, we can insert the pointer contents. Now, if a probe:vfs_getname with this format is in place: # perf probe -l probe:vfs_getname (on getname_flags:72@/home/git/linux/fs/namei.c with pathname) That was, in this case, put in place with: # perf probe 'vfs_getname=getname_flags:72 pathname=filename:string' Added new event: probe:vfs_getname (on getname_flags:72 with pathname=filename:string) You can now use it in all perf tools, such as: perf record -e probe:vfs_getname -aR sleep 1 # Then 'perf trace' will notice that and do the pointer -> contents expansion: # trace -e open touch /tmp/bla 0.165 (0.010 ms): touch/17752 open(filename: /etc/ld.so.cache, flags: CLOEXEC) = 3 0.195 (0.011 ms): touch/17752 open(filename: /lib64/libc.so.6, flags: CLOEXEC) = 3 0.512 (0.012 ms): touch/17752 open(filename: /usr/lib/locale/locale-archive, flags: CLOEXEC) = 3 0.582 (0.012 ms): touch/17752 open(filename: /tmp/bla, flags: CREAT|NOCTTY|NONBLOCK|WRONLY, mode: 438) = 3 # Roughly equivalent to strace's output: # strace -rT -e open touch /tmp/bla 0.000000 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3 <0.000039> 0.000317 open("/lib64/libc.so.6", O_RDONLY|O_CLOEXEC) = 3 <0.000102> 0.001461 open("/usr/lib/locale/locale-archive", O_RDONLY|O_CLOEXEC) = 3 <0.000072> 0.000405 open("/tmp/bla", O_WRONLY|O_CREAT|O_NOCTTY|O_NONBLOCK, 0666) = 3 <0.000055> 0.000641 +++ exited with 0 +++ # Now we need to either look for at all syscalls that are marked as pointers and have some well known names ("filename", "pathname", etc) and set the arg formatter to the one used for the "open" syscall in this patch. This implementation works for syscalls with just a string being copied from userspace, for matching syscalls with more than one string being copied via the same probe/trace point (vfs_getname) we need to extend the vfs_getname probe spec to include the pointer too, but there are some problems with that in 'perf probe' or the kernel kprobes code, need to investigate before considering supporting multiple strings per syscall. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Borislav Petkov <bp@suse.de> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Milian Wolff <mail@milianw.de> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/n/tip-xvuwx6nuj8cf389kf9s2ue2s@git.kernel.orgSigned-off-by: -
Arnaldo Carvalho de Melo authored
We were using it as a magic number, 1024, fix that. Eventually we need to stop doing it per line, and do it per arg, traversing the args at output time, to avoid the memmove() calls that will be used in the next cset to replace pointers present at raw_syscalls:sys_enter time with its contents that appear at probe:vfs_getname time, before raw_syscalls:sys_exit time. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Borislav Petkov <bp@suse.de> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Milian Wolff <mail@milianw.de> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/n/tip-4sz3wid39egay1pp8qmbur4u@git.kernel.orgSigned-off-by:
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Arnaldo Carvalho de Melo authored
So that we can later decide if we will store where to expand the pathname once we are handling vfs_getname or if we should instead just go on and straight away print the pointer. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Borislav Petkov <bp@suse.de> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Milian Wolff <mail@milianw.de> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/n/tip-ytxk5s5jpc50wahffmlxgxuw@git.kernel.orgSigned-off-by:
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Arnaldo Carvalho de Melo authored
We were accessing trace->syscalls.events members even when that struct wasn't initialized, i.e. --no-syscalls was specified on the command line, fix it to show that, still in debug mode, when we have an event qualifier list, i.e. when we actually are doing subset syscall tracing. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Borislav Petkov <bp@suse.de> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Milian Wolff <mail@milianw.de> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Stephane Eranian <eranian@google.com> Fixes: 19867b61 ("perf trace: Use event filters for the event qualifier list") Link: http://lkml.kernel.org/n/tip-7980ym6vujgh3yiai0cqzc88@git.kernel.orgSigned-off-by:
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- 04 Aug, 2015 26 commits
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Arnaldo Carvalho de Melo authored
The libtraceevent handler (session->tevent) is only initialized when there are tracepoints in a perf.data event list, so do not call pevent_set_function_resolve() in those cases, fixing a segfault. Reported-by:
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Peter Zijlstra authored
Vince Weaver and Stephane Eranian reported warnings in the PEBS code when running the perf fuzzer. Stephane wrote: > I can reproduce the problem on my HSW running the fuzzer. > > I can see why this could be happening if you are mixing PEBS and non PEBS events > in the bottom 4 counters. I suspect: > for (bit = 0; bit < x86_pmu.max_pebs_events; bit++) { > if ((counts[bit] == 0) && (error[bit] == 0)) > continue; > > This test is not correct when you have non-PEBS events mixed with > PEBS events and they overflow at the same time. They will have > counts[i] != 0 but error[i] == 0, and thus you fall thru the loop > and hit the assert. Or it is something along those lines. The only way I can make this work is if ->status only has !PEBS events set, because if it has both set we'll take that slow path which masks out the !PEBS bits. After masking there are 3 options: - there is one bit set, and its @bit, we increment counts[bit]. - there are multiple bits set, we increment error[] for each set bit, we do not increment counts[]. - there are no bits set, we do nothing. The intent was to never increment counts[] for !PEBS events. Now if we start out with only a single !PEBS event set, we'll pass the test and increment counts[] for a !PEBS and hit the warn. Reported-by:Vince Weaver <vincent.weaver@maine.edu> Reported-by:
Stephane Eranian <eranian@google.com> Signed-off-by:
Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: kan.liang@intel.com Signed-off-by:
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Liang, Kan authored
When disabling a PEBS event, we need to drain the buffer. Doing so requires a correct cpuc->pebs_active mask. The current code clears the pebs_active bit before draining the buffer. Fix that. Signed-off-by:
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Andy Lutomirski authored
This patch adds an MSR PMU to support free running MSR counters. Such as time and freq related counters includes TSC, IA32_APERF, IA32_MPERF and IA32_PPERF, but also SMI_COUNT. The events are exposed in sysfs for use by perf stat and other tools. The files are under /sys/devices/msr/events/ Signed-off-by:
Andy Lutomirski <luto@kernel.org> Signed-off-by:
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Kan Liang authored
The uncore subsystem for Broadwell-DE is similar to Haswell-EP. There are some differences in pci device IDs, box number and constraints. Please refer to the public document: http://www.intel.com/content/www/us/en/processors/xeon/xeon-d-1500-uncore-performance-monitoring.htmlSigned-off-by:
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Andi Kleen authored
The next patch adds a new perf extra register where 0x1ff is not a valid value. Use 0x11 instead. Signed-off-by:
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Andi Kleen authored
merge_attr() allows to merge two sysfs attribute tables. Export it to be usable by other files too. Next patch is going to use that to extend the sysfs format attributes for a CPU. Signed-off-by:
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Andi Kleen authored
In callstack mode the LBR is not a ring buffer, but a stack that grows up and down. This means in this case we don't need to access all LBRs, only the ones up to TOS. Do this optimization for the normal LBR read, and the context switch save/restore code. For save/restore it can be done unconditionally, as it only runs when call stack mode is active. This recovers some of the cost of going to 32 LBRs on Skylake. Signed-off-by:
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Andi Kleen authored
Use the correct index to save/restore the LBR_INFO_x MSR in callstack mode. This is more a cleanup, as even with the wrong index the register was correctly saved/restored, and also LBR callgraph mode in perf tools do not really need anything in LBR_INFO. But still better to use the right index. Signed-off-by:
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Andi Kleen authored
Add perf core PMU support for future Intel Skylake CPU cores. The code is based on Haswell/Broadwell. There is a new cache event list, based on the updated Haswell event list. Skylake has removed most counter constraints on basic events, so the basic constraints table now only has a single entry (plus the fixed counters). TSX support and various other setups are all shared with Haswell. Skylake has 32 LBR entries. Add a new LBR init function to set this up. The filters are all the same as Haswell. It also has a new LBR format with a separate LBR_INFO_* MSR, but that has been already added earlier. Signed-off-by:
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Andi Kleen authored
In Arch perfmon v4 the GLOBAL_STATUS reset automatically unfreezes LBRs. So no need to do it manually in the LBR code. Add a check to skip it. v2: Move test up to beginning of function. Signed-off-by:
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Andi Kleen authored
With Arch Perfmon v4 the PMU ack unfreezes the LBRs. So we need to do the PMU ack after the LBR reading, otherwise the LBRs would be polluted by the PMI handler. This is a minimal change. In principle the ACK could be moved much later. Signed-off-by:
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Andi Kleen authored
ArchPerfmon v4 has some new status bits in GLOBAL_STATUS. These need to be ignored when deciding whether a NMI was an NMI, to avoid eating all NMIs when they stay set, see: b292d7a1 ("perf/x86/intel: ignore CondChgd bit to avoid false NMI handling") This patch ignores the new ASIF bit, which indicates that SGX interfered with the PMU, and also the new LBR freezing bits, which are set when the LBRs get frozen, plus the existing CondChange (set by JTAG debuggers and some buggy BIOSes) Signed-off-by: -
Andi Kleen authored
Add support for the new LBRv5 format used on Intel Skylake CPUs. The flags for mispredict, abort, in_tx etc. moved to range of separate LBR_INFO_* MSRs. Teach the LBR code to read those. The original LBR registers stay the same, except they have full sign extension now. LBR_INFO also reports a cycle count to the last branch. Report the cycle information using the new "cycles" branch_info output field. In addition we have to context switch and clear the new INFO MSRs to avoid any information leaks. Signed-off-by:
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Andi Kleen authored
Intel Skylake supports reporting the time in cycles a branch in the LBR took, to give a rough indication of the basic block performance. Export the cycle information in the branch_info structure. This can be done by just reusing some currently zero padding. This is just the generic header change. The architecture still needs to fill it in. There's no attempt to convert to real time, as we really want cycles here. Signed-off-by:
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Andi Kleen authored
Add new MSRs (LBR_INFO) and some new MSR bits used by the Intel Skylake PMU driver. Signed-off-by:
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Andi Kleen authored
With PEBSv3 the PEBS record contains a time stamp. That means we can allow free-running PEBS without a PMI even if the user program requested a time stamp. This avoids the need to use -T to get free running PEBS, and also avoids any problems with mis-identifying MMAPs later. Move the free_running_flags state into a variable in x86_pmu and use it. This only works when no explicit clock_id is set. Signed-off-by:
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Andi Kleen authored
PEBSv3 is the same as the existing PEBSv2 used on Haswell, but it adds a new TSC field. Add support to the generic PEBS handler to handle the new format, and overwrite the perf time stamp using the new native_sched_clock_from_tsc(). Right now the time stamp is just slightly more accurate, as it is nearer the actual event trigger point. With the PEBS threshold > 1 patchkit it will be much more accurate, avoid the problems with MMAP mismatches earlier. The accurate time stamping is only implemented for the default trace clock for now. v2: Use _skl prefix. Check for default clock_id. Signed-off-by:
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Andi Kleen authored
PEBSv3 has a raw TSC time stamp in its memory buffer that later needs to to be converted to perf_clock. Add a native_sched_clock_from_tsc() that works the same as native_sched_clock(), but starts with an already given TSC value. Paravirt is ignored, it will just get the native clock. But there isn't a para virtualized PEBS anyway. Signed-off-by:
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Alexander Shishkin authored
Intel PT chapter in the new Intel Architecture SDM adds several packets corresponding enable bits and registers that control packet generation. Also, additional bits in the Intel PT CPUID leaf were added to enumerate presence and parameters of these new packets and features. The packets and enables are: * CYC: cycle accurate mode, provides the number of cycles elapsed since previous CYC packet; its presence and available threshold values are enumerated via CPUID; * MTC: mini time counter packets, used for tracking TSC time between full TSC packets; its presence and available resolution options are enumerated via CPUID; * PSB packet period is now configurable, available period values are enumerated via CPUID. This patch adds corresponding bit and register definitions, pmu driver capabilities based on CPUID enumeration, new attribute format bits for the new featurens and extends event configuration validation function to take these into account. Signed-off-by:Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by:
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Alexander Shishkin authored
Currently, the PT driver zeroes out the status register every time before starting the event. However, all the writable bits are already taken care of in pt_handle_status() function, except the new PacketByteCnt field, which in new versions of PT contains the number of packet bytes written since the last sync (PSB) packet. Zeroing it out before enabling PT forces a sync packet to be written. This means that, with the existing code, a sync packet (PSB and PSBEND, 18 bytes in total) will be generated every time a PT event is scheduled in. To avoid these unnecessary syncs and save a WRMSR in the fast path, this patch changes the default behavior to not clear PacketByteCnt field, so that the sync packets will be generated with the period specified as "psb_period" attribute config field. This has little impact on the trace data as the other packets that are normally sent within PSB+ (between PSB and PSBEND) have their own generation scenarios which do not depend on the sync packets. One exception where we do need to force PSB like this when tracing starts, so that the decoder has a clear sync point in the trace. For this purpose we aready have hw::itrace_started flag, which we are currently using to output PERF_RECORD_ITRACE_START. This patch moves setting itrace_started from perf core to the pmu::start, where it should still be 0 on the very first run. Signed-off-by:
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Andy Lutomirski authored
The check looked wrong, although I think it was actually safe. TASK_SIZE is unnecessarily small for compat tasks, and it wasn't possible to make a range breakpoint so large it started in user space and ended in kernel space. Nonetheless, let's fix up the check for the benefit of future readers. A breakpoint is in the kernel if either end is in the kernel. Signed-off-by:
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Andy Lutomirski authored
Range breakpoints will do the wrong thing if the address isn't aligned. While we're there, add comments about why it's safe for instruction breakpoints. Signed-off-by:
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Andy Lutomirski authored
Code on the kprobe blacklist doesn't want unexpected int3 exceptions. It probably doesn't want unexpected debug exceptions either. Be safe: disallow breakpoints in nokprobes code. On non-CONFIG_KPROBES kernels, there is no kprobe blacklist. In that case, disallow kernel breakpoints entirely. It will be particularly important to keep hw breakpoints out of the entry and NMI code once we move debug exceptions off the IST stack. Signed-off-by:
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Kan Liang authored
AVG_LATENCY(bit 38) is only available on MSR_OFFCORE_RSP0. So the bit should be removed from RSP1 valid_mask. Since RSP0 and RSP1 may have different valid_mask, intel_alt_er should validate the config on the alternate offcore reg before replacing it. Signed-off-by:
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Alexander Shishkin authored
The x86_lbr_exclusive commit (48070342 "perf/x86: Mark Intel PT and LBR/BTS as mutually exclusive") mistakenly moved intel_pmu_needs_lbr_smpl() to perf_event.h, while another commit (a46a2300 "perf: Simplify the branch stack check") removed it in favor of needs_branch_stack(). This patch gets rid of intel_pmu_needs_lbr_smpl() for good. Signed-off-by:
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