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Diffstat (limited to 'tools/perf/Documentation/perf-record.txt')
-rw-r--r-- | tools/perf/Documentation/perf-record.txt | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/tools/perf/Documentation/perf-record.txt b/tools/perf/Documentation/perf-record.txt index a5766b4b0125..60bddaf0e5bd 100644 --- a/tools/perf/Documentation/perf-record.txt +++ b/tools/perf/Documentation/perf-record.txt | |||
@@ -152,6 +152,31 @@ an empty cgroup (monitor all the time) using, e.g., -G foo,,bar. Cgroups must ha | |||
152 | corresponding events, i.e., they always refer to events defined earlier on the command | 152 | corresponding events, i.e., they always refer to events defined earlier on the command |
153 | line. | 153 | line. |
154 | 154 | ||
155 | -b:: | ||
156 | --branch-stack:: | ||
157 | Enable taken branch stack sampling. Each sample captures a series of consecutive | ||
158 | taken branches. The number of branches captured with each sample depends on the | ||
159 | underlying hardware, the type of branches of interest, and the executed code. | ||
160 | It is possible to select the types of branches captured by enabling filters. The | ||
161 | following filters are defined: | ||
162 | |||
163 | - any : any type of branches | ||
164 | - any_call: any function call or system call | ||
165 | - any_ret: any function return or system call return | ||
166 | - any_ind: any indirect branch | ||
167 | - u: only when the branch target is at the user level | ||
168 | - k: only when the branch target is in the kernel | ||
169 | - hv: only when the target is at the hypervisor level | ||
170 | |||
171 | + | ||
172 | At least one of any, any_call, any_ret, any_ind must be provided. The privilege levels may | ||
173 | be ommitted, in which case, the privilege levels of the associated event are applied to the | ||
174 | branch filter. Both kernel (k) and hypervisor (hv) privilege levels are subject to | ||
175 | permissions. When sampling on multiple events, branch stack sampling is enabled for all | ||
176 | the sampling events. The sampled branch type is the same for all events. | ||
177 | Note that taken branch sampling may not be available on all processors. | ||
178 | The various filters must be specified as a comma separated list: -b any_ret,u,k | ||
179 | |||
155 | SEE ALSO | 180 | SEE ALSO |
156 | -------- | 181 | -------- |
157 | linkperf:perf-stat[1], linkperf:perf-list[1] | 182 | linkperf:perf-stat[1], linkperf:perf-list[1] |