Yonghong Song 908432ca84 bpf: add helper bpf_perf_event_read_value for perf event array map ... Hardware pmu counters are limited resources. When there are more pmu based perf events opened than available counters, kernel will multiplex these events so each event gets certain percentage (but not 100%) of the pmu time. In case that multiplexing happens, the number of samples or counter value will not reflect the case compared to no multiplexing. This makes comparison between different runs difficult. Typically, the number of samples or counter value should be normalized before comparing to other experiments. The typical normalization is done like: normalized_num_samples = num_samples * time_enabled / time_running normalized_counter_value = counter_value * time_enabled / time_running where time_enabled is the time enabled for event and time_running is the time running for event since last normalization. This patch adds helper bpf_perf_event_read_value for kprobed based perf event array map, to read perf counter and enabled/running time. The enabled/running time is accumulated since the perf event open. To achieve scaling factor between two bpf invocations, users can can use cpu_id as the key (which is typical for perf array usage model) to remember the previous value and do the calculation inside the bpf program. Signed-off-by: Yonghong Song <yhs@fb.com> Acked-by: Alexei Starovoitov <ast@fb.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>		2017-10-07 23:05:57 +01:00
..
bpf	bpf: add helper bpf_perf_event_read_value for perf event array map	2017-10-07 23:05:57 +01:00
cgroup	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net	2017-10-05 18:19:22 -07:00
configs	ANDROID: binder: add hwbinder,vndbinder to BINDER_DEVICES.	2017-08-22 18:43:23 -07:00
debug	sched/headers: Prepare for new header dependencies before moving code to <linux/sched/debug.h>	2017-03-02 08:42:34 +01:00
events	bpf: perf event change needed for subsequent bpf helpers	2017-10-07 23:05:57 +01:00
gcov	gcov: support GCC 7.1	2017-05-12 15:57:15 -07:00
irq	irq/generic-chip: Don't replace domain's name	2017-09-28 12:18:59 +02:00
livepatch	livepatch: Fix stacking of patches with respect to RCU	2017-06-20 10:42:19 +02:00
locking	locking/rwsem-xadd: Fix missed wakeup due to reordering of load	2017-09-29 10:10:20 +02:00
power	PM / s2idle: Invoke the ->wake() platform callback earlier	2017-09-29 01:26:13 +02:00
printk	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk	2017-09-07 21:00:52 -07:00
rcu	Two updates.	2017-10-04 08:34:01 -07:00
sched	sched/debug: Ignore TASK_IDLE for SysRq-W	2017-09-29 11:02:57 +02:00
time	drivers/pps: aesthetic tweaks to PPS-related content	2017-09-08 18:26:51 -07:00
trace	bpf: add helper bpf_perf_event_read_value for perf event array map	2017-10-07 23:05:57 +01:00
.gitignore	…
Kconfig.freezer	…
Kconfig.hz	…
Kconfig.locks	…
Kconfig.preempt	…
Makefile	kmod: move #ifdef CONFIG_MODULES wrapper to Makefile	2017-09-08 18:26:51 -07:00
acct.c	fs: make the buf argument to __kernel_write a void pointer	2017-09-04 19:05:15 -04:00
async.c	async: Adjust system_state checks	2017-05-23 10:01:37 +02:00
audit.c	audit: update the function comments	2017-09-05 09:46:59 -04:00
audit.h	ipc: mqueue: Replace timespec with timespec64	2017-09-03 20:21:24 -04:00
audit_fsnotify.c	Merge branch 'fsnotify' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs	2017-05-03 11:05:15 -07:00
audit_tree.c	Merge branch 'fsnotify' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs	2017-05-03 11:05:15 -07:00
audit_watch.c	audit/stable-4.13 PR 20170816	2017-08-16 16:48:34 -07:00
auditfilter.c	audit: kernel generated netlink traffic should have a portid of 0	2017-05-02 10:16:05 -04:00
auditsc.c	Merge branch 'work.ipc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2017-09-14 17:37:26 -07:00
backtracetest.c	…
bounds.c	…
capability.c	capability: export has_capability	2017-01-12 07:01:56 -07:00
compat.c	semtimedop(): move compat to native	2017-07-15 20:46:47 -04:00
configs.c	Replace <asm/uaccess.h> with <linux/uaccess.h> globally	2016-12-24 11:46:01 -08:00
context_tracking.c	…
cpu.c	smp/hotplug: Hotplug state fail injection	2017-09-25 22:11:44 +02:00
cpu_pm.c	PM / CPU: replace raw_notifier with atomic_notifier	2017-07-31 13:09:49 +02:00
crash_core.c	kdump: protect vmcoreinfo data under the crash memory	2017-07-12 16:26:00 -07:00
crash_dump.c	…
cred.c	doc: ReSTify credentials.txt	2017-05-18 10:30:19 -06:00
delayacct.c	sched/headers: Prepare to move cputime functionality from <linux/sched.h> into <linux/sched/cputime.h>	2017-03-02 08:42:39 +01:00
dma.c	…
elfcore.c	…
exec_domain.c	…
exit.c	fix infoleak in waitid(2)	2017-09-29 13:43:15 -04:00
extable.c	extable: Enable RCU if it is not watching in kernel_text_address()	2017-09-23 16:50:20 -04:00
fork.c	android: binder: drop lru lock in isolate callback	2017-10-03 17:54:24 -07:00
freezer.c	…
futex.c	futex: Fix pi_state->owner serialization	2017-09-25 16:37:11 +02:00
futex_compat.c	Replace <asm/uaccess.h> with <linux/uaccess.h> globally	2016-12-24 11:46:01 -08:00
groups.c	kernel/groups.c: use sort library function	2017-07-10 16:32:34 -07:00
hung_task.c	kernel/hung_task.c: defer showing held locks	2017-05-08 17:15:10 -07:00
irq_work.c	…
jump_label.c	jump_label: Provide hotplug context variants	2017-08-10 12:28:59 +02:00
kallsyms.c	kernel/kallsyms.c: replace all_var with IS_ENABLED(CONFIG_KALLSYMS_ALL)	2017-07-10 16:32:34 -07:00
kcmp.c	kernel/kcmp.c: drop branch leftover typo	2017-10-03 17:54:25 -07:00
kcov.c	kcov: support compat processes	2017-09-08 18:26:51 -07:00
kexec.c	kdump: protect vmcoreinfo data under the crash memory	2017-07-12 16:26:00 -07:00
kexec_core.c	x86/mm, kexec: Allow kexec to be used with SME	2017-07-18 11:38:04 +02:00
kexec_file.c	kexec_file: adjust declaration of kexec_purgatory	2017-07-12 16:26:02 -07:00
kexec_internal.h	kexec_file: adjust declaration of kexec_purgatory	2017-07-12 16:26:02 -07:00
kmod.c	kmod: move #ifdef CONFIG_MODULES wrapper to Makefile	2017-09-08 18:26:51 -07:00
kprobes.c	kprobes: Ensure that jprobe probepoints are at function entry	2017-07-08 11:05:35 +02:00
ksysfs.c	kexec: move vmcoreinfo out of the kernel's .bss section	2017-07-12 16:25:59 -07:00
kthread.c	kernel/kthread.c: kthread_worker: don't hog the cpu	2017-08-31 16:33:15 -07:00
latencytop.c	sched/headers: Prepare to move sched_info_on() and force_schedstat_enabled() from <linux/sched.h> to <linux/sched/stat.h>	2017-03-02 08:42:39 +01:00
memremap.c	memremap: add scheduling point to devm_memremap_pages	2017-10-03 17:54:25 -07:00
module-internal.h	…
module.c	module: fix ddebug_remove_module()	2017-07-25 15:08:32 +02:00
module_signing.c	…
notifier.c	kernel/notifier.c: simplify expression	2017-02-24 17:46:56 -08:00
nsproxy.c	perf: Add PERF_RECORD_NAMESPACES to include namespaces related info	2017-03-13 15:57:41 -03:00
padata.c	padata: Avoid nested calls to cpus_read_lock() in pcrypt_init_padata()	2017-05-26 10:10:37 +02:00
panic.c	locking/refcounts, x86/asm: Implement fast refcount overflow protection	2017-08-17 10:40:26 +02:00
params.c	kernel/params.c: improve STANDARD_PARAM_DEF readability	2017-10-03 17:54:26 -07:00
pid.c	pids: make task_tgid_nr_ns() safe	2017-08-21 12:47:31 -07:00
pid_namespace.c	userns,pidns: Verify the userns for new pid namespaces	2017-07-20 07:43:58 -05:00
profile.c	sched/headers: Prepare to move sched_info_on() and force_schedstat_enabled() from <linux/sched.h> to <linux/sched/stat.h>	2017-03-02 08:42:39 +01:00
ptrace.c	signal: Remove kernel interal si_code magic	2017-07-24 14:30:28 -05:00
range.c	…
reboot.c	…
relay.c	Merge branch 'work.splice' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2017-05-02 11:38:06 -07:00
resource.c	…
seccomp.c	seccomp: fix the usage of get/put_seccomp_filter() in seccomp_get_filter()	2017-09-27 22:51:12 -07:00
signal.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace	2017-09-11 18:34:47 -07:00
smp.c	treewide: make "nr_cpu_ids" unsigned	2017-09-08 18:26:48 -07:00
smpboot.c	sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task.h>	2017-03-02 08:42:35 +01:00
smpboot.h	…
softirq.c	sched/core: Remove 'task' parameter and rename tsk_restore_flags() to current_restore_flags()	2017-04-11 09:06:32 +02:00
stacktrace.c	stacktrace/x86: add function for detecting reliable stack traces	2017-03-08 09:18:02 +01:00
stop_machine.c	stop_machine: Provide stop_machine_cpuslocked()	2017-05-26 10:10:36 +02:00
sys.c	prctl: Allow local CAP_SYS_ADMIN changing exe_file	2017-07-20 07:46:07 -05:00
sys_ni.c	move aio compat to fs/aio.c	2016-12-22 22:58:37 -05:00
sysctl.c	kernel/sysctl.c: remove duplicate UINT_MAX check on do_proc_douintvec_conv()	2017-10-03 17:54:25 -07:00
sysctl_binary.c	fs: fix kernel_write prototype	2017-09-04 19:05:15 -04:00
task_work.c	task_work: Replace spin_unlock_wait() with lock/unlock pair	2017-07-25 10:08:58 -07:00
taskstats.c	taskstats: add e/u/stime for TGID command	2017-05-08 17:15:12 -07:00
test_kprobes.c	…
torture.c	torture: Fix typo suppressing CPU-hotplug statistics	2017-07-25 13:04:45 -07:00
tracepoint.c	sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task.h>	2017-03-02 08:42:35 +01:00
tsacct.c	sched/headers: Prepare to move cputime functionality from <linux/sched.h> into <linux/sched/cputime.h>	2017-03-02 08:42:39 +01:00
ucount.c	ucount: Remove the atomicity from ucount->count	2017-03-06 15:26:37 -06:00
uid16.c	sched/headers: Prepare to remove <linux/cred.h> inclusion from <linux/sched.h>	2017-03-02 08:42:31 +01:00
umh.c	kmod: split out umh code into its own file	2017-09-08 18:26:50 -07:00
up.c	smp: Avoid using two cache lines for struct call_single_data	2017-08-29 15:14:38 +02:00
user-return-notifier.c	…
user.c	sched/headers: Prepare for new header dependencies before moving code to <linux/sched/user.h>	2017-03-02 08:42:29 +01:00
user_namespace.c	userns,pidns: Verify the userns for new pid namespaces	2017-07-20 07:43:58 -05:00
utsname.c	sched/headers: Prepare to move the task_lock()/unlock() APIs to <linux/sched/task.h>	2017-03-02 08:42:38 +01:00
utsname_sysctl.c	sched/headers: Remove <linux/rwsem.h> from <linux/sched.h>	2017-03-03 01:45:36 +01:00
watchdog.c	kernel/watchdog: Prevent false positives with turbo modes	2017-08-18 12:35:02 +02:00
watchdog_hld.c	kernel/watchdog: Prevent false positives with turbo modes	2017-08-18 12:35:02 +02:00
workqueue.c	Merge branch 'for-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq	2017-09-06 21:59:31 -07:00
workqueue_internal.h	…