libvirt/src/util/virhostcpu.h
Daniel Henrique Barboza 46d88d8dba domaincapsmock: mock virHostCPUGetMicrocodeVersion()
Previous patch handled the runtime case where a non-x86 host is
fetching /proc/cpuinfo data for a microcode info that we know
it doesn't exist. This change alone speeded everything by a
bit for non-x86, but there is at least one major culprit left.

qemuxml2argvtest does several arch-specific tests, and a good
chunk of them are x86 exclusive. This means that 'hostArch'
will be seen as x86 for these tests, even when running in
non-x86 hosts. In a Power 9 server with 128 CPUs, qemuxml2argvtest
takes 298 seconds to complete in average, and 'perf record'
indicates that 95% of the time is spent in
virHostCPUGetMicrocodeVersion().

This patch mocks virHostCPUGetMicrocodeVersion() to always return
0 in the tests, avoiding /proc/cpuinfo reads. This will make all
tests behave arch-agnostic, and the microcode value being 0 has no
impact on any existing test.

This is a CI speed across the board for all archs, including x86,
given that we're not reading /proc/cpuinfo in the tests. For
a Thinkpad T480 laptop with 8 Intel i7 CPUs, qemuxml2argvtest
went from 15.50 sec to 12.50 seconds. The performance gain is even
more noticeable for huge servers with lots of CPUs. For the
Power 9 server mentioned above, this patch speeds qemuxml2argvtest
to 9 seconds, down from 298 sec.

Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Signed-off-by: Ján Tomko <jtomko@redhat.com>
2020-08-25 19:44:43 +02:00

87 lines
2.7 KiB
C

/*
* virhostcpu.h: helper APIs for host CPU info
*
* Copyright (C) 2006-2016 Red Hat, Inc.
* Copyright (C) 2006 Daniel P. Berrange
*
* 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/>.
*/
#pragma once
#include "internal.h"
#include "virarch.h"
#include "virbitmap.h"
#include "virenum.h"
typedef struct _virHostCPUTscInfo virHostCPUTscInfo;
typedef virHostCPUTscInfo *virHostCPUTscInfoPtr;
struct _virHostCPUTscInfo {
unsigned long long frequency;
virTristateBool scaling;
};
int virHostCPUGetStats(int cpuNum,
virNodeCPUStatsPtr params,
int *nparams,
unsigned int flags);
bool virHostCPUHasBitmap(void);
virBitmapPtr virHostCPUGetPresentBitmap(void);
virBitmapPtr virHostCPUGetOnlineBitmap(void);
virBitmapPtr virHostCPUGetAvailableCPUsBitmap(void);
int virHostCPUGetCount(void);
int virHostCPUGetThreadsPerSubcore(virArch arch) G_GNUC_NO_INLINE;
int virHostCPUGetMap(unsigned char **cpumap,
unsigned int *online,
unsigned int flags);
int virHostCPUGetInfo(virArch hostarch,
unsigned int *cpus,
unsigned int *mhz,
unsigned int *nodes,
unsigned int *sockets,
unsigned int *cores,
unsigned int *threads);
int virHostCPUGetKVMMaxVCPUs(void) G_GNUC_NO_INLINE;
int virHostCPUStatsAssign(virNodeCPUStatsPtr param,
const char *name,
unsigned long long value);
#ifdef __linux__
int virHostCPUGetSocket(unsigned int cpu, unsigned int *socket);
int virHostCPUGetDie(unsigned int cpu, unsigned int *die);
int virHostCPUGetCore(unsigned int cpu, unsigned int *core);
virBitmapPtr virHostCPUGetSiblingsList(unsigned int cpu);
#endif
int virHostCPUGetOnline(unsigned int cpu, bool *online);
unsigned int
virHostCPUGetMicrocodeVersion(virArch hostArch) G_GNUC_NO_INLINE;
int virHostCPUGetMSR(unsigned long index,
uint64_t *msr);
virHostCPUTscInfoPtr virHostCPUGetTscInfo(void);
int virHostCPUGetSignature(char **signature);