Re: [PATCH v2] rt-tests: hwlatdetect.py Covert to f-strings

[Leah Leshchinsky <lleshchi@redhat.com>]

On Fri, Nov 11, 2022 at 11:46:21AM -0500, John Kacur wrote:
> 
> 
> On Wed, 9 Nov 2022, Leah Leshchinsky wrote:
> 
> > Add f-strings where applicable for readability.
> > 
> > Signed-off-by: Leah Leshchinsky <lleshchi@redhat.com>
> > 
> > diff --git a/src/hwlatdetect/hwlatdetect.py b/src/hwlatdetect/hwlatdetect.py
> > index 9ef50f862127..7b1ae646577a 100755
> > --- a/src/hwlatdetect/hwlatdetect.py
> > +++ b/src/hwlatdetect/hwlatdetect.py
> > @@ -59,7 +59,7 @@ class DebugFS:
> >          if self.premounted or self.mounted:
> >              debug("not mounting debugfs")
> >              return True
> > -        debug("mounting debugfs at %s" % path)
> > +        debug(f"mounting debugfs at {path}")
> >          self.mountpoint = path
> >          cmd = ['/bin/mount', '-t', 'debugfs', 'none', path]
> >          self.mounted = (subprocess.call(cmd) == 0)
> > @@ -90,7 +90,7 @@ class DebugFS:
> >              try:
> >                  val = f.readline()
> >              except OSError as e:
> > -                print("errno: %s" % e)
> > +                print(f"errno: {e}")
> >                  if e.errno == errno.EAGAIN:
> >                      val = None
> >                  else:
> > @@ -192,18 +192,18 @@ class Detector:
> >          count = 0
> >          threshold = int(self.get("threshold"))
> >          self.c_states_off()
> > -        debug("enabling detector module (threshold: %d)" % threshold)
> > +        debug(f"enabling detector module (threshold: {threshold})")
> >          self.set("enable", 1)
> >          while self.get("enable") == 0:
> >              debug("still disabled, retrying in a bit")
> >              count += 1
> >              time.sleep(0.1)
> > -            debug("retrying enable of detector module (%d)" % count)
> > +            debug(f"retrying enable of detector module ({count})")
> >              self.set("enable", 1)
> >          if self.get("threshold") != threshold:
> >              debug("start: threshold reset by start, fixing")
> >              self.set("threshold", threshold)
> > -        debug("detector module enabled (threshold: %d)" % int(self.get("threshold")))
> > +        debug(f"detector module enabled (threshold: {int(self.get('threshold'))})")
> >  
> >      def stop(self):
> >          """ disable the detector """
> > @@ -214,7 +214,7 @@ class Detector:
> >              debug("still enabled, retrying in a bit")
> >              count += 1
> >              time.sleep(0.1)
> > -            debug("retrying disable of detector module(%d)" % count)
> > +            debug(f"retrying disable of detector module({count})")
> >              self.set("enable", 0)
> >          self.c_states_on()
> >          debug("detector module disabled")
> > @@ -248,7 +248,7 @@ class Tracer(Detector):
> >              self.outer = int(o)
> >  
> >          def __str__(self):
> > -            return "ts: %s, inner:%d, outer:%d" % (self.timestamp, self.inner, self.outer)
> > +            return f"ts: {self.timestamp}, inner:{self.inner}, outer:{self.outer}"
> >  
> >          def display(self):
> >              """ convert object to string and print """
> > @@ -322,8 +322,8 @@ class Tracer(Detector):
> >          if output:
> >              with open(output, "w") as f:
> >                  for s in self.samples:
> > -                    f.write("%s\n" % str(s))
> > -                print("report saved to %s (%d samples)" % (output, len(self.samples)))
> > +                    f.write(f"{s}\n")
> > +                print(f"report saved to {output} ({len(self.samples)} samples)")
> >  
> >      def display(self):
> >          for s in self.samples:
> > @@ -341,7 +341,7 @@ def seconds(sval):
> >      if sval.isdigit():
> >          return int(sval)
> >      if sval[-2].isalpha():
> > -        raise RuntimeError("illegal suffix for seconds: '%s'" % sval[-2:-1])
> > +        raise RuntimeError(f"illegal suffix for seconds: '{sval[-2:-1]}'")
> >      if sval[-1:] == 's':
> >          return int(sval[0:-1])
> >      if sval[-1:] == 'm':
> > @@ -352,7 +352,7 @@ def seconds(sval):
> >          return int(sval[0:-1]) * 86400
> >      if sval[-1:] == 'w':
> >          return int(sval[0:-1]) * 86400 * 7
> > -    raise RuntimeError("invalid input for seconds: '%s'" % sval)
> > +    raise RuntimeError(f"invalid input for seconds: '{sval}'")
> >  
> >  
> >  def milliseconds(sval):
> > @@ -367,7 +367,7 @@ def milliseconds(sval):
> >          return int(sval[0:-1]) * 1000 * 60
> >      if sval[-1] == 'h':
> >          return int(sval[0:-1]) * 1000 * 60 * 60
> > -    raise RuntimeError("invalid input for milliseconds: %s" % sval)
> > +    raise RuntimeError(f"invalid input for milliseconds: {sval}")
> >  
> >  
> >  def microseconds(sval):
> > @@ -380,7 +380,7 @@ def microseconds(sval):
> >          return int(sval[0:-2])
> >      if sval[-1:] == 's':
> >          return int(sval[0:-1]) * 1000 * 1000
> > -    raise RuntimeError("invalid input for microseconds: '%s'" % sval)
> > +    raise RuntimeError(f"invalid input for microseconds: '{sval}'")
> >  
> >  
> >  if __name__ == '__main__':
> > @@ -444,37 +444,37 @@ if __name__ == '__main__':
> >      if args.threshold:
> >          t = microseconds(args.threshold)
> >          detect.set("threshold", t)
> > -        debug("threshold set to %dus" % t)
> > +        debug(f"threshold set to {t}us")
> >  
> >      if args.hardlimit:
> >          hardlimit = microseconds(args.hardlimit)
> >      else:
> >          hardlimit = int(detect.get("threshold"))
> > -    debug("hardlimit set to %dus" % hardlimit)
> > +    debug(f"hardlimit set to {hardlimit}us")
> >  
> >      if args.window:
> >          w = microseconds(args.window)
> >          if w < int(detect.get("width")):
> > -            debug("shrinking width to %d for new window of %d" % (w/2, w))
> > +            debug(f"shrinking width to {w//2} for new window of {w}")
> >              detect.set("width", w/2)
> > -        debug("window parameter = %d" % w)
> > +        debug(f"window parameter = {w}")
> >          detect.set("window", w)
> > -        debug("window for sampling set to %dus" % w)
> > +        debug(f"window for sampling set to {w}us")
> >  
> >      if args.width:
> >          w = microseconds(args.width)
> >          if w > int(detect.get("window")):
> > -            debug("widening window to %d for new width of %d" % (w*2, w))
> > +            debug(f"widening window to {w*2} for new width of {w}")
> >              detect.set("window", w*2)
> > -        debug("width parameter = %d" % w)
> > +        debug(f"width parameter = {w}")
> >          detect.set("width", w)
> > -        debug("sample width set to %dus" % w)
> > +        debug(f"sample width set to {w}us")
> >  
> >      if args.duration:
> >          detect.testduration = seconds(args.duration)
> >      else:
> >          detect.testduration = 120  # 2 minutes
> > -    debug("test duration is %ds" % detect.testduration)
> > +    debug(f"test duration is {detect.testduration}s")
> >  
> >      if args.watch:
> >          watch = True
> > @@ -491,18 +491,18 @@ if __name__ == '__main__':
> >                  l, r = map(int, [c, c])
> >              for i in range(l, r + 1):
> >                  cpumask |= (1 << i)
> > -        debug("set tracing_cpumask to %x" % cpumask)
> > -        detect.set("cpumask", "%x" % cpumask)
> > +        debug(f"set tracing_cpumask to {cpumask:x}")
> > +        detect.set("cpumask", f"{cpumask:x}")
> >  
> > -    info("hwlatdetect:  test duration %d seconds" % detect.testduration)
> > -    info("   detector: %s" % detect.type)
> > +    info(f"hwlatdetect:  test duration {detect.testduration} seconds")
> > +    info(f"   detector: {detect.type}")
> >      info("   parameters:")
> > -    info("        CPU list:          %s"   % args.cpulist)
> > +    info(f"        CPU list:          {args.cpulist}")
> >      info("        Latency threshold: %dus" % int(detect.get("threshold")))
> >      info("        Sample window:     %dus" % int(detect.get("window")))
> >      info("        Sample width:      %dus" % int(detect.get("width")))
> >      info("     Non-sampling period:  %dus" % (int(detect.get("window")) - int(detect.get("width"))))
> 
> The above 4 lines could use f-strings too
> 
> > -    info("        Output File:       %s" % reportfile)
> > +    info(f"        Output File:       {reportfile}")
> >      info("\nStarting test")
> >  
> >      detect.detect()
> > @@ -513,12 +513,12 @@ if __name__ == '__main__':
> >      if max_latency == 0:
> >          info("Max Latency: Below threshold")
> >      else:
> > -        info("Max Latency: %dus" % max_latency)
> > +        info(f"Max Latency: {int(max_latency)}us")
> 
> Why is int needed?
> 
> >  
> > -    info("Samples recorded: %d" % len(detect.samples))
> > +    info(f"Samples recorded: {int(len(detect.samples))}")
> 
> Why is int needed? 
> 
> >  
> >      exceeding = detect.get("count")
> > -    info("Samples exceeding threshold: %d" % exceeding)
> > +    info(f"Samples exceeding threshold: {exceeding}")
> >  
> >      if detect.have_msr:
> >          finishsmi = detect.getsmicounts()
> > @@ -527,8 +527,8 @@ if __name__ == '__main__':
> >              if count > detect.initsmi[i]:
> >                  smis = count - detect.initsmi[i]
> >                  total_smis += smis
> > -                print("%d SMIs occured on cpu %d" % (smis, i))
> > -        info("SMIs during run: %d" % total_smis)
> > +                print(f"{smis} SMIs occured on cpu {i}")
> > +        info(f"SMIs during run: {total_smis}")
> >  
> >      maxlatency = int(detect.get("max"))
> >  
> > -- 
> > 2.31.1
> > 
> > 
> The patch looks good on the whole, just remove the unnecessary int(var)
> and add the 4 missing lines that could be changed to f-strings.
> 
> Thanks!
> 
> John
> 
Thanks for the review! I refrained from converting those 4 lines to fstrings because it seemed less readable, but I think it's worth converting them anyways for consistency.
I will remove the > +    info(f"Samples recorded: {int(len(detect.samples))}")
int(), since it's redundant, but I'd argue to keep the int(maxlatency), as is done a few lines below in     maxlatency = int(detect.get("max"))
or to wrap the max_latency on line 513 in an int(). 

I'm also wondering, are lines 513 and 534 redundant, or do we need both max_latency definitions?

Thanks!

Leah