From d7a7671477710eca0673a54475b47a58dbf44842 Mon Sep 17 00:00:00 2001

From: Daniel Bristot de Oliveira <daniel@bristot.me>

Date: Thu, 25 Jun 2015 16:50:18 -0300

Subject: [PATCH 1/2] CLI: start a process from tuna

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Currently it is possible to set the CPU affinity and sched tunables for

threads running on a system. However, tuna does not permit to start a

new application with these parameters set.

This patch adds the ability to start a new process with its affinity

and sched tunable set before it starts to run.

To do so, one parameter was added to tuna's command line. This

parameter is the Action -r, --run=:

   -r, --run="COMMAND"

	  Run the COMMAND. If arguments are passed, the entire com‐

	  mand line must be provided inside "quotes". Modifiers  -c

	  and -p can be used to set the affinity and scheduler tun‐

	  ables of the given COMMAND. The arg[0] (i.e. the command)

	  will  be set in THREAD-LIST. Likewise the -t, the COMMAND

	  accepts the prefix + and - as wildcards in  order  to  be

	  appended or removed from THREAD-LIST, respectively.

The option -r will fork a new process, set the sched tunables and

affinity, and execute the new application's binary.

Tuna will wait for the new process to return, and then continue

its execution. That means that it is possible to execute many Actions

after the creation of a new process, including the start of many process

in a single command line.

Example of use:

[root@kiron tuna]# tuna -p fifo:1 -t bash -c 1,2 -r +httpd -P

                      thread       ctxt_switches

    pid SCHED_ rtpri affinity voluntary nonvoluntary             cmd

  10550  OTHER     0  0,1,2,3       300           81            bash

  12898  OTHER     0  0,1,2,3        30            6            bash

  12930  OTHER     0  0,1,2,3       246           27            bash

  13022   FIFO     1      1,2         1            0           httpd

In this example, the schedule policy:prio fifo:1 is saved for future

Actions, "bash" is set in Thread list, cpus 1,2 are set in the cpulist,

the command "httpd" is appended to the Thread list and is started.

Finally, the threads in Thread list are printed.

Signed-off-by: Daniel Bristot de Oliveira <daniel@bristot.me>

Signed-off-by: John Kacur <jkacur@redhat.com>

---

 tuna-cmd.py  | 98 ++++++++++++++++++++++++++++++++++++++++++++----------------

 tuna/tuna.py | 59 ++++++++++++++++++++++++++++--------

 2 files changed, 119 insertions(+), 38 deletions(-)

diff --git a/tuna-cmd.py b/tuna-cmd.py

index 3c9bfaa50bb4..164fbfcfe5e0 100755

--- a/tuna-cmd.py

+++ b/tuna-cmd.py

@@ -69,6 +69,8 @@ def usage():

 	print fmt % ('-Q, --show_irqs',		    _('Show IRQ list'))

 	print fmt % ('-q, --irqs=' + _('IRQ-LIST'), _('%(irqlist)s affected by commands') %

 							{"irqlist": _('IRQ-LIST')})

+	print fmt % ('-r, --run=' + _('COMMAND'),   _('fork a new process and run the %(command)s') % \

+							{"command": _('COMMAND')})

 	print fmt % ('-s, --save=' + _('FILENAME'), _('Save kthreads sched tunables to %(filename)s') % \

 							{"filename": _('FILENAME')})

 	print fmt % ('-S, --sockets=' +

@@ -377,8 +379,8 @@ def thread_mapper(s):

 		return [ int(s), ]

 	except:

 		pass

-	if not ps:

-		ps = procfs.pidstats()

+

+	ps = procfs.pidstats()

 	try:

 		return ps.find_by_regex(re.compile(fnmatch.translate(s)))

@@ -454,13 +456,14 @@ def main():

 	i18n_init()

 	try:

-		short = "a:c:CfgGhiIKlmNp:PQq:s:S:t:UvWx"

+		short = "a:c:CfgGhiIKlmNp:PQq:r:s:S:t:UvWx"

 		long = ["cpus=", "affect_children", "filter", "gui", "help",

 			"isolate", "include", "no_kthreads", "move", "nohz_full",

 			"show_sockets", "priority=", "show_threads",

 			"show_irqs", "irqs=",

 			"save=", "sockets=", "threads=", "no_uthreads",

-			"version", "what_is", "spread","cgroup","config_file_apply=","config_file_list="]

+			"version", "what_is", "spread","cgroup","config_file_apply=","config_file_list=",

+			"run=" ]

 		if have_inet_diag:

 			short += "n"

 			long.append("show_sockets")

@@ -477,11 +480,14 @@ def main():

 	cpu_list = None

 	irq_list = None

 	irq_list_str = None

+	rtprio = None

+	policy = None

 	thread_list = []

 	thread_list_str = None

 	filter = False

 	affect_children = False

 	show_sockets = False

+	p_waiting_action = False

 	for o, a in opts:

 		if o in ("-h", "--help"):

@@ -510,20 +516,25 @@ def main():

 		elif o in ("-G", "--cgroup"):

 			cgroups = True

 		elif o in ("-t", "--threads"):

-			(op, a) = pick_op(a)

-			op_list = reduce(lambda i, j: i + j,

-					 map(thread_mapper, a.split(",")))

-			op_list = list(set(op_list))

-			thread_list = do_list_op(op, thread_list, op_list)

-			# Check if a process name was especified and no

-			# threads was found, which would result in an empty

-			# thread list, i.e. we would print all the threads

-			# in the system when we should print nothing.

-			if not op_list and type(a) == type(''):

-				thread_list_str = do_list_op(op, thread_list_str,

-							     a.split(","))

-			if not op:

-				irq_list = None

+			# The -t - will reset thread list

+			if a == '-':

+				thread_list = []

+				thread_list_str = ''

+			else:

+				(op, a) = pick_op(a)

+				op_list = reduce(lambda i, j: i + j,

+						 map(thread_mapper, a.split(",")))

+				op_list = list(set(op_list))

+				thread_list = do_list_op(op, thread_list, op_list)

+				# Check if a process name was especified and no

+				# threads was found, which would result in an empty

+				# thread list, i.e. we would print all the threads

+				# in the system when we should print nothing.

+				if not op_list and type(a) == type(''):

+					thread_list_str = do_list_op(op, thread_list_str,

+								     a.split(","))

+				if not op:

+					irq_list = None

 		elif o in ("-f", "--filter"):

 			filter = True

 		elif o in ("-g", "--gui"):

@@ -539,14 +550,17 @@ def main():

 				sys.exit(2)

 			tuna.include_cpus(cpu_list, get_nr_cpus())

 		elif o in ("-p", "--priority"):

+			# Save policy and rtprio for future Actions (e.g. --run).

+			(policy, rtprio) = tuna.get_policy_and_rtprio(a)

 			if not thread_list:

-				print ("tuna: %s " % o) + _("requires a thread list!")

-				sys.exit(2)

-			try:

-				tuna.threads_set_priority(thread_list, a, affect_children)

-			except (SystemError, OSError) as err: # (3, 'No such process') old python-schedutils incorrectly raised SystemError

-				print "tuna: %s" % err

-				sys.exit(2)

+				# For backward compatibility

+				p_waiting_action = True

+			else:

+				try:

+					tuna.threads_set_priority(thread_list, a, affect_children)

+				except (SystemError, OSError) as err: # (3, 'No such process') old python-schedutils incorrectly raised SystemError

+					print "tuna: %s" % err

+					sys.exit(2)

 		elif o in ("-P", "--show_threads"):

 			# If the user specified process names that weren't

 			# resolved to pids, don't show all threads.

@@ -637,6 +651,40 @@ def main():

 				sys.exit(2)

 			for tid in thread_list:

 				thread_help(tid)

+		elif o in ("-r", "--run"):

+			# If -p is set, it will be consumed. So, no backward compatible

+			# error handling action must be taken.

+			p_waiting_action = False

+

+			# pick_op() before run the command: to remove the prefix

+			# + or - from command line.

+			(op, a) = pick_op(a)

+

+			# In order to include the new process, it must run

+			# the command first, and then get the list of pids,

+			tuna.run_command(a, policy, rtprio, cpu_list)

+

+			op_list = reduce(lambda i, j: i + j,

+					 map(thread_mapper, a.split(",")))

+			op_list = list(set(op_list))

+			thread_list = do_list_op(op, thread_list, op_list)

+

+			# Check if a process name was especified and no

+			# threads was found, which would result in an empty

+			# thread list, i.e. we would print all the threads

+			# in the system when we should print nothing.

+			if not op_list and type(a) == type(''):

+				thread_list_str = do_list_op(op, thread_list_str,

+							     a.split(","))

+			if not op:

+				irq_list = None

+

+	# For backward compatibility: when -p used to be only an Action, it

+	# used to exit(2) if no action was taken (i.e. if no threads_list

+	# was set).

+	if p_waiting_action:

+		print ("tuna: -p ") + _("requires a thread list!")

+		sys.exit(2)

 	if run_gui:

 		try:

diff --git a/tuna/tuna.py b/tuna/tuna.py

index 646b8dfa700f..9aab16a409d2 100755

--- a/tuna/tuna.py

+++ b/tuna/tuna.py

@@ -1,7 +1,7 @@

 # -*- python -*-

 # -*- coding: utf-8 -*-

-import copy, ethtool, os, procfs, re, schedutils

+import copy, ethtool, os, procfs, re, schedutils, sys, shlex

 import help, fnmatch

 from procfs import utilist

@@ -498,6 +498,22 @@ def get_irq_affinity_text(irqs, irq):

 		# needs root prio to read /proc/irq/<NUM>/smp_affinity

 		return ""

+def get_policy_and_rtprio(parm):

+	parms = parm.split(":")

+	rtprio = 0

+	policy = None

+	if parms[0].upper() in ["OTHER", "BATCH", "IDLE", "FIFO", "RR"]:

+		policy = schedutils.schedfromstr("SCHED_%s" % parms[0].upper())

+		if len(parms) > 1:

+			rtprio = int(parms[1])

+		elif parms[0].upper() in ["FIFO", "RR"]:

+			rtprio = 1

+	elif parms[0].isdigit():

+		rtprio = int(parms[0])

+	else:

+		raise ValueError

+	return (policy, rtprio)

+

 def thread_filtered(tid, cpus_filtered, show_kthreads, show_uthreads):

 	if cpus_filtered:

 		try:

@@ -532,18 +548,9 @@ def thread_set_priority(tid, policy, rtprio):

 	schedutils.set_scheduler(tid, policy, rtprio)

 def threads_set_priority(tids, parm, affect_children = False):

-	parms = parm.split(":")

-	rtprio = 0

-	policy = None

-	if parms[0].upper() in ["OTHER", "BATCH", "IDLE", "FIFO", "RR"]:

-		policy = schedutils.schedfromstr("SCHED_%s" % parms[0].upper())

-		if len(parms) > 1:

-			rtprio = int(parms[1])

-		elif parms[0].upper() in ["FIFO", "RR"]:

-			rtprio = 1

-	elif parms[0].isdigit():

-		rtprio = int(parms[0])

-	else:

+	try:

+		(policy, rtprio) = get_policy_and_rtprio(parm)

+	except ValueError:

 		print "tuna: " + _("\"%s\" is unsupported priority value!") % parms[0]

 		return

@@ -602,6 +609,32 @@ def get_kthread_sched_tunings(proc = None):

 	return kthreads

+def run_command(cmd, policy, rtprio, cpu_list):

+	newpid = os.fork()

+	if newpid == 0:

+		cmd_list = shlex.split(cmd)

+		pid = os.getpid()

+		if rtprio:

+			try:

+				thread_set_priority(pid, policy, rtprio)

+			except (SystemError, OSError) as err:

+				print "tuna: %s" % err

+				sys.exit(2)

+		if cpu_list:

+			try:

+				schedutils.set_affinity(pid, cpu_list)

+			except (SystemError, OSError) as err:

+				print "tuna: %s" % err

+				sys.exit(2)

+

+		try:

+			os.execvp(cmd_list[0], cmd_list)

+		except (SystemError, OSError) as err:

+			print "tuna: %s" % err

+			sys.exit(2)

+	else:

+		os.waitpid(newpid, 0);

+

 def generate_rtgroups(filename, kthreads, nr_cpus):

 	f = file(filename, "w")

 	f.write('''# Generated by tuna

-- 

2.4.11