Operating Systems 2022F: Assignment 4 - Revision history

Soma at 16:31, 8 December 2022

2022-12-08T16:31:27Z

← Older revision		Revision as of 16:31, 8 December 2022
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	}		}
	</syntaxhighlight>		</syntaxhighlight>

			==Solutions==

			[https://homeostasis.scs.carleton.ca/~soma/os-2022f/solutions/a4-sol.txt Assignment 4 Solutions]

Soma: /* Questions */

2022-11-26T15:59:48Z

Questions

← Older revision		Revision as of 15:59, 26 November 2022
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	# [2] What is the purpose of line 127, a call to put_user()? Why can't this line be replaced with a simple array assignment?		# [2] What is the purpose of line 127, a call to put_user()? Why can't this line be replaced with a simple array assignment?
	# [1] What is the purpose of line 111, a call to put_user()? Remove this line and report how the behavior of the module changes.		# [1] What is the purpose of line 111, a call to put_user()? Remove this line and report how the behavior of the module changes.
	# [2] What is the purpose of the calls to get_zeroed_page() (line 104) and free_page() (line ~~131~~)? What happens if either is missing?		# [2] What is the purpose of the calls to get_zeroed_page() (line 104) and free_page() (line 132)? What happens if either is missing?
	# [4] Change c3000procreport so that it reports not just the calling process but also lists all of the process's ancestors until there are no more to report. You should support up to 10 levels of ancestor processes. Each report should be on a line saying "PID's parent is PID", where the PID's are process IDs.		# [4] Change c3000procreport so that it reports not just the calling process but also lists all of the process's ancestors until there are no more to report. You should support up to 10 levels of ancestor processes. Each report should be on a line saying "PID's parent is PID", where the PID's are process IDs.
	# [4] Change c3000procreport so that it reports the address of all the intermediate lookups in when determining the physical address corresponding to the read buffer's virtual address.		# [4] Change c3000procreport so that it reports the address of all the intermediate lookups in when determining the physical address corresponding to the read buffer's virtual address.

Soma: /* Questions */

2022-11-26T15:58:13Z

Questions

← Older revision		Revision as of 15:58, 26 November 2022
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	# [2] Run <tt>bpftrace watch_procreport.bt</tt> in one terminal and then run <tt>dd if=/dev/procreport bs=1024 count=1</tt>. What does the bpftrace script report? Why are we getting this output? Explain what you see.		# [2] Run <tt>bpftrace watch_procreport.bt</tt> in one terminal and then run <tt>dd if=/dev/procreport bs=1024 count=1</tt>. What does the bpftrace script report? Why are we getting this output? Explain what you see.
	# [2] If you run the command <tt>dd if=/dev/procreport seek=1 bs=1024 count=1</tt>, what happens? Does <tt>bpftrace watch_procreport.bt</tt> give you any insight as to what is happening?		# [2] If you run the command <tt>dd if=/dev/procreport seek=1 bs=1024 count=1</tt>, what happens? Does <tt>bpftrace watch_procreport.bt</tt> give you any insight as to what is happening?
	# [2] What is the purpose of line ~~126~~, a call to put_user()? Why can't this line be replaced with a simple array assignment?		# [2] What is the purpose of line 127, a call to put_user()? Why can't this line be replaced with a simple array assignment?
	# [1] What is the purpose of line 111, a call to put_user()? Remove this line and report how the behavior of the module changes.		# [1] What is the purpose of line 111, a call to put_user()? Remove this line and report how the behavior of the module changes.
	# [2] What is the purpose of the calls to get_zeroed_page() (line 104) and free_page() (line 131)? What happens if either is missing?		# [2] What is the purpose of the calls to get_zeroed_page() (line 104) and free_page() (line 131)? What happens if either is missing?

Soma: /* c3000procreport.c */

2022-11-26T15:56:50Z

c3000procreport.c

← Older revision		Revision as of 15:56, 26 November 2022
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	msglen = strlen(message);		msglen = strlen(message);
			msglen++;

	if (len < msglen) {		if (len < msglen) {

Soma at 17:19, 25 November 2022

2022-11-25T17:19:11Z

← Older revision		Revision as of 17:19, 25 November 2022
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	~~'''The questions below are basically finalized, you can begin work. Submission instructions will be added here shortly.'''~~

	Please submit the answers to the following questions via Brightspace by December 7, 2022 by 11:59 PM. There are 20 points in 9 questions.		Please submit the answers to the following questions via Brightspace by December 7, 2022 by 11:59 PM. There are 20 points in 9 questions.

Soma at 17:18, 25 November 2022

2022-11-25T17:18:58Z

← Older revision		Revision as of 17:18, 25 November 2022
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	'''The questions below are basically finalized, you can begin work. Submission instructions will be added here shortly.'''		'''The questions below are basically finalized, you can begin work. Submission instructions will be added here shortly.'''

	Please submit the answers to the following questions via Brightspace by ~~November 21~~, 2022 by 11:59 PM. There are 20 points in 9 questions.		Please submit the answers to the following questions via Brightspace by December 7, 2022 by 11:59 PM. There are 20 points in 9 questions.

	Submit your answers as a plain text file following [https://homeostasis.scs.carleton.ca/~soma/os-2022f/templates/comp3000-a4-template.txt this template]. Name your answer file "comp3000-assign4-<username>.txt" (where username is your MyCarletonOne username). '''Please make sure your submission passes the [https://homeostasis.scs.carleton.ca/~soma/os-2022f/validators/a4-validator.html assignment validator].'''		Submit your answers as a plain text file following [https://homeostasis.scs.carleton.ca/~soma/os-2022f/templates/comp3000-a4-template.txt this template]. Name your answer file "comp3000-assign4-<username>.txt" (where username is your MyCarletonOne username). '''Please make sure your submission passes the [https://homeostasis.scs.carleton.ca/~soma/os-2022f/validators/a4-validator.html assignment validator].'''

Soma at 17:13, 25 November 2022

2022-11-25T17:13:09Z

← Older revision		Revision as of 17:13, 25 November 2022
Line 1:		Line 1:
	'''The questions below are basically finalized, you can begin work. Submission instructions will be added here shortly.'''		'''The questions below are basically finalized, you can begin work. Submission instructions will be added here shortly.'''

			Please submit the answers to the following questions via Brightspace by November 21, 2022 by 11:59 PM. There are 20 points in 9 questions.

			Submit your answers as a plain text file following [https://homeostasis.scs.carleton.ca/~soma/os-2022f/templates/comp3000-a4-template.txt this template]. Name your answer file "comp3000-assign4-<username>.txt" (where username is your MyCarletonOne username). '''Please make sure your submission passes the [https://homeostasis.scs.carleton.ca/~soma/os-2022f/validators/a4-validator.html assignment validator].'''

			Don't forget to include what outside resources you used to complete each of your answers, including other students, man pages, and web resources. You do not need to list help from the instructor, TA, or information found in the textbook.


	==Questions==		==Questions==

Soma at 05:41, 25 November 2022

2022-11-25T05:41:27Z

← Older revision		Revision as of 05:41, 25 November 2022
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	'''~~This assignment is still being developed~~.'''		'''The questions below are basically finalized, you can begin work. Submission instructions will be added here shortly.'''

	==Questions==		==Questions==

Soma: /* Questions */

2022-11-25T05:40:39Z

Questions

← Older revision		Revision as of 05:40, 25 November 2022
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	# [2] What is the purpose of line 126, a call to put_user()? Why can't this line be replaced with a simple array assignment?		# [2] What is the purpose of line 126, a call to put_user()? Why can't this line be replaced with a simple array assignment?
	# [1] What is the purpose of line 111, a call to put_user()? Remove this line and report how the behavior of the module changes.		# [1] What is the purpose of line 111, a call to put_user()? Remove this line and report how the behavior of the module changes.
	# [2] What is the purpose of the calls to get_zeroed_page() (line 104) and free_page() (line ~~134~~)? What happens if either is missing?		# [2] What is the purpose of the calls to get_zeroed_page() (line 104) and free_page() (line 131)? What happens if either is missing?
	# [4] Change c3000procreport so that it reports not just the calling process but also lists all of the process's ancestors until there are no more to report. You should support up to 10 levels of ancestor processes. Each report should be on a line saying "PID's parent is PID", where the PID's are process IDs.		# [4] Change c3000procreport so that it reports not just the calling process but also lists all of the process's ancestors until there are no more to report. You should support up to 10 levels of ancestor processes. Each report should be on a line saying "PID's parent is PID", where the PID's are process IDs.
	# [4] Change c3000procreport so that it reports the address of all the intermediate lookups in when determining the physical address corresponding to the read buffer's virtual address.		# [4] Change c3000procreport so that it reports the address of all the intermediate lookups in when determining the physical address corresponding to the read buffer's virtual address.

Soma: /* Questions */

2022-11-25T05:39:31Z

Questions

← Older revision		Revision as of 05:39, 25 November 2022
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	# [2] Run <tt>bpftrace watch_procreport.bt</tt> in one terminal and then run <tt>dd if=/dev/procreport bs=1024 count=1</tt>. What does the bpftrace script report? Why are we getting this output? Explain what you see.		# [2] Run <tt>bpftrace watch_procreport.bt</tt> in one terminal and then run <tt>dd if=/dev/procreport bs=1024 count=1</tt>. What does the bpftrace script report? Why are we getting this output? Explain what you see.
	# [2] If you run the command <tt>dd if=/dev/procreport seek=1 bs=1024 count=1</tt>, what happens? Does <tt>bpftrace watch_procreport.bt</tt> give you any insight as to what is happening?		# [2] If you run the command <tt>dd if=/dev/procreport seek=1 bs=1024 count=1</tt>, what happens? Does <tt>bpftrace watch_procreport.bt</tt> give you any insight as to what is happening?
	# [2] What is the purpose of line ~~122~~, a call to put_user()? Why can't this line be replaced with a simple array assignment?		# [2] What is the purpose of line 126, a call to put_user()? Why can't this line be replaced with a simple array assignment?
	# [1] What is the purpose of line 111, a call to put_user()? Remove this line and report how the behavior of the module changes.		# [1] What is the purpose of line 111, a call to put_user()? Remove this line and report how the behavior of the module changes.
	# [2] What is the purpose of the calls to get_zeroed_page() (line 104) and free_page() (line 134)? What happens if either is missing?		# [2] What is the purpose of the calls to get_zeroed_page() (line 104) and free_page() (line 134)? What happens if either is missing?