resctrl: Add functions to work with resctrl allocations

With this commit we finally have a way to read and manipulate basic resctrl
settings.  Locking is done only on exposed functions that read/write from/to
resctrlfs.  Not in functions that are exposed in virresctrlpriv.h as those are
only supposed to be used from tests.

More information about how resctrl works:

  https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/x86/intel_rdt_ui.txtSigned-off-by: NMartin Kletzander <mkletzan@redhat.com>

src/Makefile.am

@@ -167,7 +167,7 @@ UTIL_SOURCES = \
 		util/virprocess.c util/virprocess.h \
 		util/virqemu.c util/virqemu.h \
 		util/virrandom.h util/virrandom.c \
-		util/virresctrl.h util/virresctrl.c \
+		util/virresctrl.h util/virresctrl.c util/virresctrlpriv.h \
 		util/virrotatingfile.h util/virrotatingfile.c \
 		util/virscsi.c util/virscsi.h \
 		util/virscsihost.c util/virscsihost.h \

src/libvirt_private.syms

@@ -2552,6 +2552,16 @@ virRandomInt;
 # util/virresctrl.h
 virCacheTypeFromString;
 virCacheTypeToString;
+virResctrlAllocAddPID;
+virResctrlAllocCreate;
+virResctrlAllocForeachSize;
+virResctrlAllocFormat;
+virResctrlAllocGetID;
+virResctrlAllocGetUnused;
+virResctrlAllocNew;
+virResctrlAllocRemove;
+virResctrlAllocSetID;
+virResctrlAllocSetSize;
 virResctrlGetInfo;
 virResctrlInfoGetCache;
 virResctrlInfoNew;

src/util/virresctrl.h

@@ -65,4 +65,53 @@ virResctrlInfoGetCache(virResctrlInfoPtr resctrl,
                        size_t *ncontrols,
                        virResctrlInfoPerCachePtr **controls);
 
+/* Alloc-related things */
+typedef struct _virResctrlAlloc virResctrlAlloc;
+typedef virResctrlAlloc *virResctrlAllocPtr;
+
+typedef int virResctrlAllocForeachSizeCallback(unsigned int level,
+                                               virCacheType type,
+                                               unsigned int cache,
+                                               unsigned long long size,
+                                               void *opaque);
+
+virResctrlAllocPtr
+virResctrlAllocNew(void);
+
+bool
+virResctrlAllocIsEmpty(virResctrlAllocPtr resctrl);
+
+int
+virResctrlAllocSetSize(virResctrlAllocPtr resctrl,
+                       unsigned int level,
+                       virCacheType type,
+                       unsigned int cache,
+                       unsigned long long size);
+
+int
+virResctrlAllocForeachSize(virResctrlAllocPtr resctrl,
+                           virResctrlAllocForeachSizeCallback cb,
+                           void *opaque);
+
+int
+virResctrlAllocSetID(virResctrlAllocPtr alloc,
+                     const char *id);
+const char *
+virResctrlAllocGetID(virResctrlAllocPtr alloc);
+
+char *
+virResctrlAllocFormat(virResctrlAllocPtr alloc);
+
+int
+virResctrlAllocCreate(virResctrlInfoPtr r_info,
+                      virResctrlAllocPtr alloc,
+                      const char *machinename);
+
+int
+virResctrlAllocAddPID(virResctrlAllocPtr alloc,
+                      pid_t pid);
+
+int
+virResctrlAllocRemove(virResctrlAllocPtr alloc);
+
 #endif /*  __VIR_RESCTRL_H__ */

src/util/virresctrlpriv.h

+/*
+ * virresctrlpriv.h:
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library.  If not, see
+ * <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __VIR_RESCTRL_PRIV_H__
+# define __VIR_RESCTRL_PRIV_H__
+
+# include "virresctrl.h"
+
+virResctrlAllocPtr
+virResctrlAllocGetUnused(virResctrlInfoPtr resctrl);
+
+#endif /* __VIR_RESCTRL_PRIV_H__ */