| author | Matti Laitinen <matti.t.laitinen@nokia.com> |
| Thu, 11 Feb 2010 15:32:31 +0200 | |
| changeset 2 | b9ab3b238396 |
| child 5 | 844b047e260d |
| permissions | -rw-r--r-- |
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b9ab3b238396
Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
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b9ab3b238396
Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
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b9ab3b238396
Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
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b9ab3b238396
Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
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b9ab3b238396
Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
diff
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b9ab3b238396
Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
diff
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<title>Delayed Function Call</title> |
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b9ab3b238396
Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
diff
changeset
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b9ab3b238396
Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
diff
changeset
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</head> |
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b9ab3b238396
Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
diff
changeset
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b9ab3b238396
Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
diff
changeset
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<body> |
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b9ab3b238396
Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
diff
changeset
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<h3>Delayed Function Call</h3> |
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b9ab3b238396
Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
diff
changeset
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<P LANG="en-GB" ALIGN=JUSTIFY>A delayed function call (DFC) is a feature within the Symbian interrupt architecture. DFCs are used to perform interrupt-related activities that are too time-consuming to be processed in the interrupt service routine (ISR). Symbian kernel keeps a list of all DFCs queued to be processed. An ISR can add a DFC to the queue at any time, but the actual processing of the DFCs takes place only after all the ISRs have been processed first, but before the control is taken back to the scheduled threads. In addition to the exit from the interrupt handling, the DFC queue is also processed in the context of exit from a kernel executive call or a kernel server call.</P> |
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b9ab3b238396
Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
diff
changeset
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<P LANG="en-GB" ALIGN=JUSTIFY>Performance measurements can utilize DFCs in activities that require processing that cannot be performed within the interrupts. Such processing could be, for example, exporting buffered data from privileged buffers to user-mode software. In addition, performance measurements should take into account the time spent within the DFCs, since the activities that take place in them do not belong to the normal processing of the scheduled threads.</P> |
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b9ab3b238396
Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
diff
changeset
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<div id="footer">Copyright © 2009 Nokia Corporation and/or its subsidiary(-ies). All rights reserved. <br>License: <a href="http://www.eclipse.org/legal/epl-v10.html">http://www.eclipse.org/legal/epl-v10.html</a></div> |
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b9ab3b238396
Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
diff
changeset
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</body> |
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b9ab3b238396
Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
diff
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</html> |