This is a very basic example, demonstrating the usage of the new
high-level (OOP) APIs for kernel histograms.
Signed-off-by: Yordan Karadzhov (VMware) <y.karadz@xxxxxxxxx>
---
examples/hist_oop.py | 81 ++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 81 insertions(+)
create mode 100644 examples/hist_oop.py
diff --git a/examples/hist_oop.py b/examples/hist_oop.py
new file mode 100644
index 0000000..1a3aab6
--- /dev/null
+++ b/examples/hist_oop.py
@@ -0,0 +1,81 @@
+#!/usr/bin/env python3
+
+"""
+SPDX-License-Identifier: CC-BY-4.0
+
+Copyright 2021 VMware Inc, Yordan Karadzhov (VMware) <y.karadz@xxxxxxxxx>
+"""
+
+import sys
+import time
+
+import tracecruncher.ft_utils as tc
+
+name = 'khist_example_oop'
+
+cmds = ['start', 'stop', 'show', 'continue', 'clear', 'close']
+
+evt = tc.event('kmem', 'kmalloc')
+
+axes={'call_site': 'sym',
+ 'bytes_req': 'n'}
+
+weights=['bytes_alloc']
+
+sort_keys=['bytes_req', 'bytes_alloc']
+
+sort_dir={'bytes_req': 'desc'}
+
+if __name__ == "__main__":
+ if len(sys.argv) != 2:
+ sys.exit(1)
+
+ if not sys.argv[1].isdigit() and not sys.argv[1] in cmds:
+ sys.exit(1)
+
+ arg1 = sys.argv[1]
+ if arg1.isdigit() or arg1 == 'start':
+ # Create the kernel tracing histogram.
+ hist = tc.create_khist(name=name, event=evt, axes=axes, weights=weights,
+ sort_keys=sort_keys, sort_dir=sort_dir)
+ # Start taking data.
+ hist.start()
+
+ if arg1.isdigit():
+ # Take data for a while, then stop, print the result and exit. The
+ # trace-cruncher module will take care for clearing and destroying
+ # the histogram in the kernel.
+ time.sleep(int(arg1))
+ hist.stop()
+ print(hist.data())
+
+ else:
+ # Detach the 'hist' object from the trace-cruncher module. This will
+ # prevent the kernel histogram from being destroyed when the module
+ # is closed (at exit).
+ hist.detach()
+
+ else:
+ # Try to find an existing histogram with the same definition.
+ # The returned histogram is detached from the trace-cruncher module.
+ hist = tc.find_khist(name=name, event=evt, axes=axes, weights=weights,
+ sort_keys=sort_keys, sort_dir=sort_dir)
+
+ if arg1 == 'stop':
+ # Stop taking data.
+ hist.stop()
+ elif arg1 == 'show':
+ # Print the collected data.
+ print(hist.data())
+ elif arg1 == 'continue':
+ # Continue taking data.
+ hist.resume()
+ elif arg1 == 'clear':
+ # Reset the histogram.
+ hist.clear()
+
+ if arg1 == 'close':
+ # Attach the 'hist' object to the trace-cruncher module. This will
+ # ensure that the kernel histogram will be destroyed when the
+ # module is closed (at exit).
+ hist.attach()
--
2.32.0
|