From 702382ac8b5385ce15f807016582b54793141c4b Mon Sep 17 00:00:00 2001

From: Dan Callaghan <dcallagh@redhat.com>

Date: Mon, 13 Jul 2015 15:06:59 +1000

Subject: [PATCH 18/26] guess memory size from memory hotplug info (#694)

---

 src/core/Makefile |  2 +-

 src/core/mem.cc   | 35 +++++++++++++++++++++++++++++++++--

 src/core/sysfs.cc | 16 ++++++++++++++++

 src/core/sysfs.h  |  2 ++

 4 files changed, 52 insertions(+), 3 deletions(-)

diff --git a/src/core/Makefile b/src/core/Makefile

index 2d95a80..884a963 100644

--- a/src/core/Makefile

+++ b/src/core/Makefile

@@ -39,7 +39,7 @@ main.o: device-tree.h pci.h pcmcia.h pcmcia-legacy.h ide.h scsi.h spd.h

 main.o: network.h isapnp.h fb.h usb.h sysfs.h display.h parisc.h cpufreq.h

 main.o: ideraid.h mounts.h smp.h abi.h s390.h virtio.h pnp.h vio.h

 print.o: print.h hw.h options.h version.h osutils.h config.h

-mem.o: version.h config.h mem.h hw.h

+mem.o: version.h config.h mem.h hw.h sysfs.h

 dmi.o: version.h config.h dmi.h hw.h osutils.h

 device-tree.o: version.h device-tree.h hw.h osutils.h

 cpuinfo.o: version.h cpuinfo.h hw.h osutils.h

diff --git a/src/core/mem.cc b/src/core/mem.cc

index 686cc16..72bfb35 100644

--- a/src/core/mem.cc

+++ b/src/core/mem.cc

@@ -5,9 +5,10 @@

  * sources:

  * - the size of /proc/kcore

  * - the value returned by the sysconf libc function

+ * - the sum of sizes of kernel hotplug memory blocks

  * - the sum of sizes of individual memory banks

  *

- * NOTE: Except in last case, this guess can be widely inaccurate, as the

+ * NOTE: In the first two cases this guess can be widely inaccurate, as the

  * kernel itself limits the memory addressable by userspace processes.

  * Because of that, this module reports the biggest value found if it can't

  * access the size of individual memory banks (information filled in by other

@@ -17,6 +18,7 @@

 #include "version.h"

 #include "config.h"

+#include "sysfs.h"

 #include "mem.h"

 #include <sys/types.h>

 #include <sys/stat.h>

@@ -52,6 +54,31 @@ static unsigned long long get_sysconf_size()

 }

+static unsigned long long get_hotplug_size()

+{

+  vector < sysfs::entry > entries = sysfs::entries_by_bus("memory");

+

+  if (entries.empty())

+    return 0;

+

+  unsigned long long memblocksize =

+    sysfs::entry::byPath("/system/memory").hex_attr("block_size_bytes");

+  if (memblocksize == 0)

+    return 0;

+

+  unsigned long long totalsize = 0;

+  for (vector < sysfs::entry >::iterator it = entries.begin();

+      it != entries.end(); ++it)

+  {

+    const sysfs::entry & e = *it;

+    if (e.string_attr("online") != "1")

+      continue;

+    totalsize += memblocksize;

+  }

+  return totalsize;

+}

+

+

 static unsigned long long count_memorybanks_size(hwNode & n)

 {

   hwNode *memory = n.getChild("core/memory");

@@ -93,9 +120,11 @@ bool scan_memory(hwNode & n)

   hwNode *memory = n.getChild("core/memory");

   unsigned long long logicalmem = 0;

   unsigned long long kcore = 0;

+  unsigned long long hotplug_size = 0;

   logicalmem = get_sysconf_size();

   kcore = get_kcore_size();

+  hotplug_size = get_hotplug_size();

   count_memorybanks_size(n);

   claim_memory(n);

@@ -127,7 +156,9 @@ bool scan_memory(hwNode & n)

     if (memory->getSize() > logicalmem)           // we already have a value

       return true;

-    if ((logicalmem == 0)

+    if (hotplug_size > logicalmem)

+      memory->setSize(hotplug_size);

+    else if ((logicalmem == 0)

       || ((kcore > logicalmem) && (kcore < 2 * logicalmem)))

       memory->setSize(kcore);

     else

diff --git a/src/core/sysfs.cc b/src/core/sysfs.cc

index fb7f2bb..d17d33d 100644

--- a/src/core/sysfs.cc

+++ b/src/core/sysfs.cc

@@ -239,6 +239,13 @@ entry entry::byClass(string devclass, string devname)

 }

+entry entry::byPath(string path)

+{

+  entry e(fs.path + "/devices" + path);

+  return e;

+}

+

+

 entry::entry(const string & devpath)

 {

   This = new entry_i;

@@ -318,6 +325,15 @@ string entry::string_attr(const string & name, const string & def) const

 }

+unsigned long long entry::hex_attr(const string & name, unsigned long long def) const

+{

+  string val = string_attr(name, "");

+  if (val.empty())

+    return def;

+  return strtoull(val.c_str(), NULL, 16);

+}

+

+

 vector < string > entry::multiline_attr(const string & name) const

 {

   vector < string > lines;

diff --git a/src/core/sysfs.h b/src/core/sysfs.h

index 7ceb395..a6d69ed 100644

--- a/src/core/sysfs.h

+++ b/src/core/sysfs.h

@@ -15,6 +15,7 @@ namespace sysfs

       static entry byBus(string devbus, string devname);

       static entry byClass(string devclass, string devname);

+      static entry byPath(string path);

       entry & operator =(const entry &);

       entry(const entry &);

@@ -28,6 +29,7 @@ namespace sysfs

       entry parent() const;

       string name_in_class(const string &) const;

       string string_attr(const string & name, const string & def = "") const;

+      unsigned long long hex_attr(const string & name, unsigned long long def = 0) const;

       vector < string > multiline_attr(const string & name) const;

       struct entry_i * This;

-- 

2.10.2