这个结构体struct read_format不是固定的,会根据组内计数器数量和struct perf_event_attr的read_format字段的设置而变化。上面的代码用了最简单的方法,把struct perf_event_attr的read_format设置为PERF_FORMAT_GROUP,那么每次读取的结构体其实就是1+nr个64位整数,其中第一个整数nr就是计数器数量,后面nr个整数就是...
I think this is a pretty reasonable trade off if you read theman pageofbpf_perf_event_read_value If youreallywant 5.4 then we can discuss that as it's not trivial.
/proc/sys/kernel/perf_event_paranoid文件用于控制Linux内核对性能事件(perf events)的访问限制。这个值决定了非特权用户(即非root用户)可以访问哪些性能事件。 较低的值表示更宽松的访问控制,而较高的值表示更严格的访问控制。 为何无法创建该文件: /proc/sys/kernel/目录下的文件并不是普通的文件系统文件,而是...
allow $1 domain:perf_event read; ') 2 changes: 2 additions & 0 deletions 2 policy/modules/roles/unconfineduser.te Original file line numberDiff line numberDiff line change @@ -81,6 +81,8 @@ kernel_rw_unlabeled_rawip_socket(unconfined_t) kernel_rw_unlabeled_smc_socket(unconfined_t) ke...
PERF_FORMAT_TOTAL_TIME_ENABLED是启用事件监视的总时间，而PERF_FORMAT_TOTAL_TIME_RUNNING是实际监视事件...
Event ID 2001: Unable to read the "First Counter" value under the usbperf\Performance Key. Status codes returned in data. Event ID 201, 202, 200 - DeviceSetupManager Event ID 219 "The driver \Driver\WudfRd failed to load for the device..." Event ID 256 — System Catalog Database...
perf_event_attr);//监测硬件attr.type=PERF_TYPE_HARDWARE;//监测指令数attr.config=PERF_COUNT_HW_INSTRUCTIONS;//初始状态为禁用attr.disabled=1;//每次读取一个组attr.read_format=PERF_FORMAT_GROUP;//创建perf文件描述符,其中pid=0,cpu=-1表示监测当前进程,不论运行在那个cpu上int fd=perf_event_open(...
简介:perf_event_open 学习 —— 通过read的方式读取硬件技术器 目录 示例程序1 单计数器 多计数器 示例程序2 Configure a single counter Configure multiple counters (no multiplexing) 示例程序1 Linux perf子系统的使用(一)——计数 刚刚入职的时候我就研究了perf_event_open()这个巨无霸级别的系统调用,还用Py...
tools/perf/util/trace-event-read.c:353: leaked_storage: Variable "sys" going out of scope leaks the storage it points to. Signed-off-by: Sanskriti Sharma <sansharm@redhat.com> Reviewed-by: Jiri Olsa <jolsa@kernel.org> Cc: Joe Lawrence <joe.lawrence@redhat.com> Link: http://lkml....
Perf events are represented by a file descriptor which can be passed between processes, e.g. via a UNIX socket or DBus. The perf event's label is inherited from the creating process at the time of ...