From ce8cacdd515bf7270daef62648d5f994f111cded Mon Sep 17 00:00:00 2001

From: John Kacur <jkacur@redhat.com>

Date: Thu, 2 Dec 2021 16:52:10 -0500

Subject: [PATCH 1/2] python-linux-procfs: Various clean-ups

- Replace f=open with 'with' (context managers), except in try-except blocks

- Reformat lines that are too long, especially in comments

- Use min() instead of if construct

- Use bool instead of complicated and True or False constructs

- Reorder imports

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

---

 procfs/procfs.py | 292 +++++++++++++++++++++++------------------------

 1 file changed, 142 insertions(+), 150 deletions(-)

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

index a0e9977214fe..a78bac5376e3 100755

--- a/procfs/procfs.py

+++ b/procfs/procfs.py

@@ -19,10 +19,10 @@

 #

 import os

-import time

-from functools import reduce

 import platform

 import re

+import time

+from functools import reduce

 from six.moves import range

 from procfs.utilist import bitmasklist

@@ -37,8 +37,9 @@ def is_s390():

 def process_cmdline(pid_info):

     """

-    Returns the process command line, if available in the given `process' class, if

-    not available, falls back to using the comm (short process name) in its pidstat key.

+    Returns the process command line, if available in the given `process' class,

+    if not available, falls back to using the comm (short process name) in its

+    pidstat key.

     """

     if pid_info["cmdline"]:

         return reduce(lambda a, b: a + " %s" % b, pid_info["cmdline"]).strip()

@@ -47,10 +48,12 @@ def process_cmdline(pid_info):

 class pidstat:

-    """Provides a dictionary to access the fields in the per process /proc/PID/stat

-       files.

+    """

+    Provides a dictionary to access the fields in the

+    per process /proc/PID/stat files.

-       One can obtain the available fields asking for the keys of the dictionary, e.g.:

+    One can obtain the available fields by asking for the keys of the

+    dictionary, e.g.:

         >>> p = procfs.pidstat(1)

         >>> print p.keys()

@@ -182,8 +185,7 @@ class pidstat:

         Returns true if this process has a fixed smp affinity mask,

                 not allowing it to be moved to a different set of CPUs.

         """

-        return self.fields["flags"] & self.PF_THREAD_BOUND and \

-            True or False

+        return bool(self.fields["flags"] & self.PF_THREAD_BOUND)

     def process_flags(self):

         """

@@ -193,33 +195,34 @@ class pidstat:

         As of v4.2-rc7 these include (from include/linux/sched.h comments):

-            PF_EXITING       Getting shut down

-            PF_EXITPIDONE       Pi exit done on shut down

+            PF_EXITING        Getting shut down

+            PF_EXITPIDONE     Pi exit done on shut down

             PF_VCPU           I'm a virtual CPU

-            PF_WQ_WORKER       I'm a workqueue worker

-            PF_FORKNOEXEC       Forked but didn't exec

-            PF_MCE_PROCESS       Process policy on mce errors

-            PF_SUPERPRIV       Used super-user privileges

+            PF_WQ_WORKER      I'm a workqueue worker

+            PF_FORKNOEXEC     Forked but didn't exec

+            PF_MCE_PROCESS    Process policy on mce errors

+            PF_SUPERPRIV      Used super-user privileges

             PF_DUMPCORE       Dumped core

             PF_SIGNALED       Killed by a signal

             PF_MEMALLOC       Allocating memory

-            PF_NPROC_EXCEEDED  Set_user noticed that RLIMIT_NPROC was exceeded

-            PF_USED_MATH       If unset the fpu must be initialized before use

-            PF_USED_ASYNC       Used async_schedule*(), used by module init

+            PF_NPROC_EXCEEDED Set_user noticed that RLIMIT_NPROC was exceeded

+            PF_USED_MATH      If unset the fpu must be initialized before use

+            PF_USED_ASYNC     Used async_schedule*(), used by module init

             PF_NOFREEZE       This thread should not be frozen

-            PF_FROZEN       Frozen for system suspend

-            PF_FSTRANS       Inside a filesystem transaction

-            PF_KSWAPD       I am kswapd

+            PF_FROZEN          Frozen for system suspend

+            PF_FSTRANS         Inside a filesystem transaction

+            PF_KSWAPD          I am kswapd

             PF_MEMALLOC_NOIO   Allocating memory without IO involved

             PF_LESS_THROTTLE   Throttle me less: I clean memory

-            PF_KTHREAD       I am a kernel thread

+            PF_KTHREAD         I am a kernel thread

             PF_RANDOMIZE       Randomize virtual address space

             PF_SWAPWRITE       Allowed to write to swap

             PF_NO_SETAFFINITY  Userland is not allowed to meddle with cpus_allowed

             PF_MCE_EARLY       Early kill for mce process policy

-            PF_MUTEX_TESTER       Thread belongs to the rt mutex tester

-            PF_FREEZER_SKIP       Freezer should not count it as freezable

-            PF_SUSPEND_TASK       This thread called freeze_processes and should not be frozen

+            PF_MUTEX_TESTER    Thread belongs to the rt mutex tester

+            PF_FREEZER_SKIP    Freezer should not count it as freezable

+            PF_SUSPEND_TASK    This thread called freeze_processes and

+                               should not be frozen

         """

         sflags = []

@@ -236,8 +239,8 @@ class pidstat:

 def cannot_set_affinity(self, pid):

     PF_NO_SETAFFINITY = 0x04000000

     try:

-        return int(self.processes[pid]["stat"]["flags"]) & \

-            PF_NO_SETAFFINITY and True or False

+        return bool(int(self.processes[pid]["stat"]["flags"]) &

+                    PF_NO_SETAFFINITY)

     except:

         return True

@@ -245,19 +248,21 @@ def cannot_set_affinity(self, pid):

 def cannot_set_thread_affinity(self, pid, tid):

     PF_NO_SETAFFINITY = 0x04000000

     try:

-        return int(self.processes[pid].threads[tid]["stat"]["flags"]) & \

-            PF_NO_SETAFFINITY and True or False

+        return bool(int(self.processes[pid].threads[tid]["stat"]["flags"]) &

+                    PF_NO_SETAFFINITY)

     except:

         return True

 class pidstatus:

     """

-    Provides a dictionary to access the fields in the per process /proc/PID/status

-    files. This provides additional information about processes and threads to what

-    can be obtained with the procfs.pidstat() class.

+    Provides a dictionary to access the fields

+    in the per process /proc/PID/status files.

+    This provides additional information about processes and threads to

+    what can be obtained with the procfs.pidstat() class.

-    One can obtain the available fields asking for the keys of the dictionary, e.g.:

+    One can obtain the available fields by asking for the keys of the

+    dictionary, e.g.:

         >>> import procfs

         >>> p = procfs.pidstatus(1)

@@ -312,19 +317,18 @@ class pidstatus:

         return fieldname in self.fields

     def load(self, basedir="/proc"):

-        f = open("%s/%d/status" % (basedir, self.pid))

         self.fields = {}

-        for line in f.readlines():

-            fields = line.split(":")

-            if len(fields) != 2:

-                continue

-            name = fields[0]

-            value = fields[1].strip()

-            try:

-                self.fields[name] = int(value)

-            except:

-                self.fields[name] = value

-        f.close()

+        with open("%s/%d/status" % (basedir, self.pid)) as f:

+            for line in f.readlines():

+                fields = line.split(":")

+                if len(fields) != 2:

+                    continue

+                name = fields[0]

+                value = fields[1].strip()

+                try:

+                    self.fields[name] = int(value)

+                except:

+                    self.fields[name] = value

 class process:

@@ -380,14 +384,13 @@ class process:

         del self.threads[self.pid]

     def load_cgroups(self):

-        f = open("/proc/%d/cgroup" % self.pid)

         self.cgroups = ""

-        for line in reversed(f.readlines()):

-            if len(self.cgroups) != 0:

-                self.cgroups = self.cgroups + "," + line[:-1]

-            else:

-                self.cgroups = line[:-1]

-        f.close()

+        with open("/proc/%d/cgroup" % self.pid) as f:

+            for line in reversed(f.readlines()):

+                if len(self.cgroups) != 0:

+                    self.cgroups = self.cgroups + "," + line[:-1]

+                else:

+                    self.cgroups = line[:-1]

     def load_environ(self):

         """

@@ -416,12 +419,11 @@ class process:

         >>>

         """

         self.environ = {}

-        f = open("/proc/%d/environ" % self.pid)

-        for x in f.readline().split('\0'):

-            if len(x) > 0:

-                y = x.split('=')

-                self.environ[y[0]] = y[1]

-        f.close()

+        with open("/proc/%d/environ" % self.pid) as f:

+            for x in f.readline().split('\0'):

+                if len(x) > 0:

+                    y = x.split('=')

+                    self.environ[y[0]] = y[1]

 class pidstats:

@@ -465,18 +467,18 @@ class pidstats:

     def reload(self):

         """

-        This operation will throw away the current dictionary contents, if any, and

-        read all the pid files from /proc/, instantiating a 'process' instance for

-        each of them.

+        This operation will throw away the current dictionary contents,

+        if any, and read all the pid files from /proc/, instantiating a

+        'process' instance for each of them.

-        This is a high overhead operation, and should be avoided if the perf python

-        binding can be used to detect when new threads appear and existing ones

-        terminate.

+        This is a high overhead operation, and should be avoided if the

+        perf python binding can be used to detect when new threads appear

+        and existing ones terminate.

         In RHEL it is found in the python-perf rpm package.

-        More information about the perf facilities can be found in the 'perf_event_open'

-        man page.

+        More information about the perf facilities can be found in the

+        'perf_event_open' man page.

         """

         del self.processes

         self.processes = {}

@@ -643,24 +645,21 @@ class interrupts:

     def reload(self):

         del self.interrupts

         self.interrupts = {}

-        f = open("/proc/interrupts")

-

-        for line in f.readlines():

-            line = line.strip()

-            fields = line.split()

-            if fields[0][:3] == "CPU":

-                self.nr_cpus = len(fields)

-                continue

-            irq = fields[0].strip(":")

-            self.interrupts[irq] = {}

-            self.interrupts[irq] = self.parse_entry(fields[1:], line)

-            try:

-                nirq = int(irq)

-            except:

-                continue

-            self.interrupts[irq]["affinity"] = self.parse_affinity(nirq)

-

-        f.close()

+        with open("/proc/interrupts") as f:

+            for line in f.readlines():

+                line = line.strip()

+                fields = line.split()

+                if fields[0][:3] == "CPU":

+                    self.nr_cpus = len(fields)

+                    continue

+                irq = fields[0].strip(":")

+                self.interrupts[irq] = {}

+                self.interrupts[irq] = self.parse_entry(fields[1:], line)

+                try:

+                    nirq = int(irq)

+                except:

+                    continue

+                self.interrupts[irq]["affinity"] = self.parse_affinity(nirq)

     def parse_entry(self, fields, line):

         dict = {}

@@ -681,9 +680,8 @@ class interrupts:

     def parse_affinity(self, irq):

         try:

-            f = open("/proc/irq/%s/smp_affinity" % irq)

-            line = f.readline()

-            f.close()

+            with open("/proc/irq/%s/smp_affinity" % irq) as f:

+                line = f.readline()

             return bitmasklist(line, self.nr_cpus)

         except IOError:

             return [0, ]

@@ -741,11 +739,11 @@ class cmdline:

     """

     Parses the kernel command line (/proc/cmdline), turning it into a dictionary."

-    Useful to figure out if some kernel boolean knob has been turned on, as well

-    as to find the value associated to other kernel knobs.

+    Useful to figure out if some kernel boolean knob has been turned on,

+    as well as to find the value associated to other kernel knobs.

-    It can also be used to find out about parameters passed to the init process,

-    such as 'BOOT_IMAGE', etc.

+    It can also be used to find out about parameters passed to the

+    init process, such as 'BOOT_IMAGE', etc.

     E.g.:

     >>> import procfs

@@ -762,15 +760,13 @@ class cmdline:

         self.parse()

     def parse(self):

-        f = open("/proc/cmdline")

-        for option in f.readline().strip().split():

-            fields = option.split("=")

-            if len(fields) == 1:

-                self.options[fields[0]] = True

-            else:

-                self.options[fields[0]] = fields[1]

-

-        f.close()

+        with open("/proc/cmdline") as f:

+            for option in f.readline().strip().split():

+                fields = option.split("=")

+                if len(fields) == 1:

+                    self.options[fields[0]] = True

+                else:

+                    self.options[fields[0]] = fields[1]

     def __getitem__(self, key):

         return self.options[key]

@@ -790,9 +786,9 @@ class cpuinfo:

     Dictionary with information about CPUs in the system.

     Please refer to 'man procfs(5)' for further information about the

-        '/proc/cpuinfo' file, that is the source of the information provided by this

-        class. The 'man lscpu(1)' also has information about a program that uses

-    the '/proc/cpuinfo' file.

+    '/proc/cpuinfo' file, that is the source of the information provided

+    by this class. The 'man lscpu(1)' also has information about a program that

+    uses the '/proc/cpuinfo' file.

     Using this class one can obtain the number of CPUs in a system:

@@ -801,14 +797,14 @@ class cpuinfo:

           4

     It is also possible to figure out aspects of the CPU topology, such as

-    how many CPU physical sockets exists, i.e. groups of CPUs sharing components

-    such as CPU memory caches:

+    how many CPU physical sockets exists, i.e. groups of CPUs sharing

+    components such as CPU memory caches:

       >>> print len(cpus.sockets)

       1

-    Additionally dictionary with information common to all CPUs in the system is

-    available:

+    Additionally dictionary with information common to all CPUs in the system

+    is available:

       >>> print cpus["model name"]

           Intel(R) Core(TM) i7-3667U CPU @ 2.00GHz

@@ -836,28 +832,26 @@ class cpuinfo:

         return self.tags

     def parse(self, filename):

-        f = open(filename)

-        for line in f.readlines():

-            line = line.strip()

-            if not line:

-                continue

-            fields = line.split(":")

-            tagname = fields[0].strip().lower()

-            if tagname == "processor":

-                self.nr_cpus += 1

-                continue

-            if is_s390() and tagname == "cpu number":

-                self.nr_cpus += 1

-                continue

-            if tagname == "core id":

-                continue

-            self.tags[tagname] = fields[1].strip()

-            if tagname == "physical id":

-                socket_id = self.tags[tagname]

-                if socket_id not in self.sockets:

-                    self.sockets.append(socket_id)

-

-        f.close()

+        with open(filename) as f:

+            for line in f.readlines():

+                line = line.strip()

+                if not line:

+                    continue

+                fields = line.split(":")

+                tagname = fields[0].strip().lower()

+                if tagname == "processor":

+                    self.nr_cpus += 1

+                    continue

+                if is_s390() and tagname == "cpu number":

+                    self.nr_cpus += 1

+                    continue

+                if tagname == "core id":

+                    continue

+                self.tags[tagname] = fields[1].strip()

+                if tagname == "physical id":

+                    socket_id = self.tags[tagname]

+                    if socket_id not in self.sockets:

+                        self.sockets.append(socket_id)

         self.nr_sockets = self.sockets and len(self.sockets) or \

             (self.nr_cpus /

              ("siblings" in self.tags and int(self.tags["siblings"]) or 1))

@@ -870,7 +864,8 @@ class smaps_lib:

     Representation of an mmap in place for a process. Can be used to figure

     out which processes have an library mapped, etc.

-    The 'perm' member can be used to figure out executable mmaps, i.e. libraries.

+    The 'perm' member can be used to figure out executable mmaps,

+    i.e. libraries.

     The 'vm_start' and 'vm_end' in turn can be used when trying to resolve

     processor instruction pointer addresses to a symbol name in a library.

@@ -967,13 +962,12 @@ class smaps:

         return self.entries[index]

     def reload(self):

-        f = open("/proc/%d/smaps" % self.pid)

         line = None

-        while True:

-            line = self.parse_entry(f, line)

-            if not line:

-                break

-        f.close()

+        with("/proc/%d/smaps" % self.pid) as f:

+            while True:

+                line = self.parse_entry(f, line)

+                if not line:

+                    break

         self.nr_entries = len(self.entries)

     def find_by_name_fragment(self, fragment):

@@ -1055,18 +1049,17 @@ class cpusstats:

     def reload(self):

         last_entries = self.entries

         self.entries = {}

-        f = open(self.filename)

-        for line in f.readlines():

-            fields = line.strip().split()

-            if fields[0][:3].lower() != "cpu":

-                continue

-            c = cpustat(fields)

-            if c.name == "cpu":

-                idx = 0

-            else:

-                idx = int(c.name[3:]) + 1

-            self.entries[idx] = c

-        f.close()

+        with open(self.filename) as f:

+            for line in f.readlines():

+                fields = line.strip().split()

+                if fields[0][:3].lower() != "cpu":

+                    continue

+                c = cpustat(fields)

+                if c.name == "cpu":

+                    idx = 0

+                else:

+                    idx = int(c.name[3:]) + 1

+                self.entries[idx] = c

         last_time = self.time

         self.time = time.time()

         if last_entries:

@@ -1082,8 +1075,7 @@ class cpusstats:

                     (curr.nice - prev.nice) + \

                     (curr.system - prev.system)

                 curr.usage = (delta / interval_hz) * 100

-                if curr.usage > 100:

-                    curr.usage = 100

+                curr.usage = min(curr.usage, 100)

 if __name__ == '__main__':

-- 

2.31.1