rteval/SOURCES/rteval-Check-whether-cpu-online-before-adding-to-list.patch
2022-02-03 05:24:03 +00:00

120 lines
4.2 KiB
Diff

From f65d46723cd0e2d3a9b1f788b0ffa51e7fd04f8b Mon Sep 17 00:00:00 2001
From: John Kacur <jkacur@redhat.com>
Date: Thu, 23 May 2019 17:54:20 +0200
Subject: [PATCH 1/2] rteval: Check whether a cpu is online before adding it to
the list
Check whether a cpu is online before adding it to the list
If sys online files exist, use them to determine if a cpu is online
This is done in two places, misc.py, and also in systopology which is
getting the cpus from the numa node in /sys/devices, including offline
cpus
Signed-off-by: John Kacur <jkacur@redhat.com>
---
rteval/misc.py | 19 ++++++++++++++++++-
rteval/systopology.py | 29 ++++++++++++++++++++++++-----
2 files changed, 42 insertions(+), 6 deletions(-)
diff --git a/rteval/misc.py b/rteval/misc.py
index 7c9991483728..a43a8964e061 100644
--- a/rteval/misc.py
+++ b/rteval/misc.py
@@ -36,7 +36,24 @@ def expand_cpulist(cpulist):
return [ str(i) for i in list(set(result)) ]
def online_cpus():
- return [ str(c.replace('/sys/devices/system/cpu/cpu', '')) for c in glob.glob('/sys/devices/system/cpu/cpu[0-9]*') ]
+ online_cpus = []
+ # Check for the online file with cpu1 since cpu0 can't always be offlined
+ if os.path.exists('/sys/devices/system/cpu/cpu1/online'):
+ for c in glob.glob('/sys/devices/system/cpu/cpu[0-9]*'):
+ num = str(c.replace('/sys/devices/system/cpu/cpu',''))
+ # On some machine you can't turn off cpu0
+ if not os.path.exists(c + '/online') and num == "0":
+ online_cpus.append(num)
+ else:
+ with open(c + '/online') as f:
+ is_online = f.read().rstrip('\n')
+ if is_online == "1":
+ online_cpus.append(num)
+ else: # use the old heuristic
+ for c in glob.glob('/sys/devices/system/cpu/cpu[0-9]*'):
+ num = str(c.replace('/sys/devices/system/cpu/cpu',''))
+ online_cpus.append(num)
+ return online_cpus
def invert_cpulist(cpulist):
return [ c for c in online_cpus() if c not in cpulist]
diff --git a/rteval/systopology.py b/rteval/systopology.py
index 97a6037e83aa..07674658df8e 100644
--- a/rteval/systopology.py
+++ b/rteval/systopology.py
@@ -45,6 +45,7 @@ class CpuList(object):
self.cpulist = cpulist
elif type(cpulist) is str:
self.cpulist = self.__expand_cpulist(cpulist)
+ self.cpulist = self.online_cpulist(self.cpulist)
self.cpulist.sort()
def __str__(self):
@@ -56,6 +57,10 @@ class CpuList(object):
def __len__(self):
return len(self.cpulist)
+ def online_file_exists(self):
+ if os.path.exists('/sys/devices/system/cpu/cpu1/online'):
+ return True
+ return False
# return the index of the last element of a sequence
# that steps by one
@@ -68,7 +73,6 @@ class CpuList(object):
return idx
return lim - 1
-
#
# collapse a list of cpu numbers into a string range
# of cpus (e.g. 0-5, 7, 9)
@@ -110,15 +114,30 @@ class CpuList(object):
return self.cpulist
# check whether cpu n is online
- def isonline(self, n):
+ def is_online(self, n):
if n not in self.cpulist:
raise RuntimeError("invalid cpu number %d" % n)
if n == 0:
return True
path = os.path.join(CpuList.cpupath,'cpu%d' % n)
- if os.path.exists(path):
- return sysread(path, "online") == 1
- return False
+ # Some hardware doesn't allow cpu0 to be turned off
+ if not os.path.exists(path + '/online') and n == 0:
+ return True
+ else:
+ return sysread(path, "online") == "1"
+
+ # Given a cpulist, return a cpulist of online cpus
+ def online_cpulist(self, cpulist):
+ # This only works if the sys online files exist
+ if not self.online_file_exists():
+ return cpulist
+ newlist = []
+ for cpu in cpulist:
+ if not self.online_file_exists() and cpu == '0':
+ newlist.append(cpu)
+ elif self.is_online(int(cpu)):
+ newlist.append(cpu)
+ return newlist
#
# class to abstract access to NUMA nodes in /sys filesystem
--
2.20.1