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Diffstat (limited to 'Documentation/admin-guide/workload-tracing.rst')
| -rw-r--r-- | Documentation/admin-guide/workload-tracing.rst | 41 |
1 files changed, 29 insertions, 12 deletions
diff --git a/Documentation/admin-guide/workload-tracing.rst b/Documentation/admin-guide/workload-tracing.rst index 35963491b9f1..314e5f03474e 100644 --- a/Documentation/admin-guide/workload-tracing.rst +++ b/Documentation/admin-guide/workload-tracing.rst @@ -202,6 +202,15 @@ database. To get out of this mode press ctrl+d. -p option is used to specify the number of file path components to display. -p10 is optimal for browsing kernel sources. +Alternatively, the kernel build system can generate the cscope database:: + + make cscope + +To exclude directories from the generated database, pass IGNORE_DIRS to +the cscope target. For example, to exclude Documentation/, run:: + + make IGNORE_DIRS="Documentation" cscope + What is perf and how do we use it? ================================== @@ -243,13 +252,21 @@ which can help mitigate performance regressions. It also acts as a common benchmarking framework, enabling developers to easily create test cases, integrate transparently, and use performance-rich tooling. -"perf bench all" command runs the following benchmarks: +"perf bench all" runs all available benchmarks in the perf bench +framework. The exact set of benchmarks depends on the perf version and on +the features enabled when perf was built. + +To list the benchmark collections available on the current system, run:: + + perf bench + +To list benchmarks in a collection, run:: + + perf bench <collection> + +For example, to list the benchmarks in the mem collection, run:: - * sched/messaging - * sched/pipe - * syscall/basic - * mem/memcpy - * mem/memset + perf bench mem What is stress-ng and how do we use it? ======================================= @@ -271,17 +288,17 @@ exercised: The following command runs the stressor:: - stress-ng --netdev 1 -t 60 --metrics command. + stress-ng --netdev 1 -t 60 --metrics We can use the perf record command to record the events and information associated with a process. This command records the profiling data in the perf.data file in the same directory. Using the following commands you can record the events associated with the -netdev stressor, view the generated report perf.data and annotate the to -view the statistics of each instruction of the program:: +netdev stressor, view the generated report perf.data and annotate the output +to view the statistics of each instruction of the program:: - perf record stress-ng --netdev 1 -t 60 --metrics command. + perf record -- stress-ng --netdev 1 -t 60 --metrics perf report perf annotate @@ -349,13 +366,13 @@ times each system call is invoked, and the corresponding Linux subsystem. +-------------------+-----------+-----------------+-------------------------+ | geteuid | 1 | Process Mgmt. | sys_geteuid() | +-------------------+-----------+-----------------+-------------------------+ -| getegid | 1 | Process Mgmt. | sys_getegid | +| getegid | 1 | Process Mgmt. | sys_getegid() | +-------------------+-----------+-----------------+-------------------------+ | close | 49951 | Filesystem | sys_close() | +-------------------+-----------+-----------------+-------------------------+ | pipe | 604 | Filesystem | sys_pipe() | +-------------------+-----------+-----------------+-------------------------+ -| openat | 48560 | Filesystem | sys_opennat() | +| openat | 48560 | Filesystem | sys_openat() | +-------------------+-----------+-----------------+-------------------------+ | fstat | 8338 | Filesystem | sys_fstat() | +-------------------+-----------+-----------------+-------------------------+ |