| Message ID | 8631DC5930FA9E468F04F3FD3A5D00721AFE03F0@USINDEM103.corp.hds.com |
|---|---|
| State | New |
| Headers | show |
Satoru Moriya <satoru.moriya@hds.com> writes: > ChangeLog: > v3 > - Modify os_mlock() to return error code > - Update configure_realtime() to handle return value from os_mlock() > - Change the variable name from is_mlock to enable_mlock in configure_realtime() > - Rebase qemu version 1.4.50 > > v2 > - Change option name from -mlock to -realtime mlock=on|off > - Rebase qemu version 1.3.91 > - Update patch description > > We have some plans to migrate legacy enterprise systems which require > low latency (10 msec order) to kvm virtualized environment. In our > usecase, the system runs with other untrusted guests and so locking > memory which is used by the system is needed to avoid latency > impacts from other guests' memory activity. > > --- By putting this here, you're going to mess up the commit message. Everything below '---' gets chopped off. You want to move the changelog below the --- and the commit message above it. Please submit a v4 with a corrected commit message. Regards, Anthony Liguori > In certain scenario, latency induced by paging is significant and > memory locking is needed. Also, in the scenario with untrusted > guests, latency improvement due to mlock is desired. > > This patch introduces a following new option to mlock guest and > qemu memory: > > -realtime mlock=on|off > > Signed-off-by: Satoru Moriya <satoru.moriya@hds.com> > Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> > Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com> > > --- > include/sysemu/os-posix.h | 1 + > include/sysemu/os-win32.h | 5 +++++ > os-posix.c | 12 ++++++++++++ > qemu-options.hx | 13 +++++++++++++ > vl.c | 34 ++++++++++++++++++++++++++++++++++ > 5 files changed, 65 insertions(+) > > diff --git a/include/sysemu/os-posix.h b/include/sysemu/os-posix.h > index 7f198e4..25d0b2a 100644 > --- a/include/sysemu/os-posix.h > +++ b/include/sysemu/os-posix.h > @@ -31,6 +31,7 @@ void os_set_proc_name(const char *s); > void os_setup_signal_handling(void); > void os_daemonize(void); > void os_setup_post(void); > +int os_mlock(void); > > typedef struct timeval qemu_timeval; > #define qemu_gettimeofday(tp) gettimeofday(tp, NULL) > diff --git a/include/sysemu/os-win32.h b/include/sysemu/os-win32.h > index 71f5fa0..bf8523a 100644 > --- a/include/sysemu/os-win32.h > +++ b/include/sysemu/os-win32.h > @@ -106,4 +106,9 @@ static inline bool is_daemonized(void) > return false; > } > > +static inline int os_mlock(void) > +{ > + return -ENOSYS; > +} > + > #endif > diff --git a/os-posix.c b/os-posix.c > index 5c64518..d39261d 100644 > --- a/os-posix.c > +++ b/os-posix.c > @@ -363,3 +363,15 @@ bool is_daemonized(void) > { > return daemonize; > } > + > +int os_mlock(void) > +{ > + int ret = 0; > + > + ret = mlockall(MCL_CURRENT | MCL_FUTURE); > + if (ret < 0) { > + perror("mlockall"); > + } > + > + return ret; > +} > diff --git a/qemu-options.hx b/qemu-options.hx > index 06dd565..1ec9541 100644 > --- a/qemu-options.hx > +++ b/qemu-options.hx > @@ -2569,6 +2569,19 @@ STEXI > Do not start CPU at startup (you must type 'c' in the monitor). > ETEXI > > +DEF("realtime", HAS_ARG, QEMU_OPTION_realtime, > + "-realtime [mlock=on|off]\n" > + " run qemu with realtime features\n" > + " mlock=on|off controls mlock support (default: on)\n", > + QEMU_ARCH_ALL) > +STEXI > +@item -realtime mlock=on|off > +@findex -realtime > +Run qemu with realtime features. > +mlocking qemu and guest memory can be enabled via @option{mlock=on} > +(enabled by default). > +ETEXI > + > DEF("gdb", HAS_ARG, QEMU_OPTION_gdb, \ > "-gdb dev wait for gdb connection on 'dev'\n", QEMU_ARCH_ALL) > STEXI > diff --git a/vl.c b/vl.c > index aeed7f4..71bbcf1 100644 > --- a/vl.c > +++ b/vl.c > @@ -521,6 +521,18 @@ static QemuOptsList qemu_tpmdev_opts = { > }, > }; > > +static QemuOptsList qemu_realtime_opts = { > + .name = "realtime", > + .head = QTAILQ_HEAD_INITIALIZER(qemu_realtime_opts.head), > + .desc = { > + { > + .name = "mlock", > + .type = QEMU_OPT_BOOL, > + }, > + { /* end of list */ } > + }, > +}; > + > const char *qemu_get_vm_name(void) > { > return qemu_name; > @@ -1420,6 +1432,20 @@ static void smp_parse(const char *optarg) > max_cpus = smp_cpus; > } > > +static void configure_realtime(QemuOpts *opts) > +{ > + bool enable_mlock; > + > + enable_mlock = qemu_opt_get_bool(opts, "mlock", true); > + > + if (enable_mlock) { > + if (os_mlock() < 0) { > + fprintf(stderr, "qemu: locking memory failed\n"); > + exit(1); > + } > + } > +} > + > /***********************************************************/ > /* USB devices */ > > @@ -2909,6 +2935,7 @@ int main(int argc, char **argv, char **envp) > qemu_add_opts(&qemu_add_fd_opts); > qemu_add_opts(&qemu_object_opts); > qemu_add_opts(&qemu_tpmdev_opts); > + qemu_add_opts(&qemu_realtime_opts); > > runstate_init(); > > @@ -3878,6 +3905,13 @@ int main(int argc, char **argv, char **envp) > exit(1); > } > break; > + case QEMU_OPTION_realtime: > + opts = qemu_opts_parse(qemu_find_opts("realtime"), optarg, 0); > + if (!opts) { > + exit(1); > + } > + configure_realtime(opts); > + break; > default: > os_parse_cmd_args(popt->index, optarg); > } > -- > 1.7.11.7
> -----Original Message----- > From: Anthony Liguori [mailto:aliguori@us.ibm.com] > Sent: Tuesday, March 26, 2013 10:28 AM > To: Satoru Moriya; qemu-devel@nongnu.org > Cc: Jan Kiszka; dle-develop@lists.sourceforge.net; Seiji Aguchi; Paolo Bonzini; mtosatti@redhat.com; > Tomoki Sekiyama; satoru.moriya.br@hitachi.com > Subject: Re: [Qemu-devel] [PATCH v3] Add option to mlock qemu and guest memory > > Satoru Moriya <satoru.moriya@hds.com> writes: > > > ChangeLog: > > v3 > > - Modify os_mlock() to return error code > > - Update configure_realtime() to handle return value from os_mlock() > > - Change the variable name from is_mlock to enable_mlock in > > configure_realtime() > > - Rebase qemu version 1.4.50 > > > > v2 > > - Change option name from -mlock to -realtime mlock=on|off > > - Rebase qemu version 1.3.91 > > - Update patch description > > > > We have some plans to migrate legacy enterprise systems which require > > low latency (10 msec order) to kvm virtualized environment. In our > > usecase, the system runs with other untrusted guests and so locking > > memory which is used by the system is needed to avoid latency impacts > > from other guests' memory activity. > > > > --- > > By putting this here, you're going to mess up the commit message. > Everything below '---' gets chopped off. > > You want to move the changelog below the --- and the commit message above it. > > Please submit a v4 with a corrected commit message. Thanks. I'll post v4 soon. Regards, Satoru
diff --git a/include/sysemu/os-posix.h b/include/sysemu/os-posix.h index 7f198e4..25d0b2a 100644 --- a/include/sysemu/os-posix.h +++ b/include/sysemu/os-posix.h @@ -31,6 +31,7 @@ void os_set_proc_name(const char *s); void os_setup_signal_handling(void); void os_daemonize(void); void os_setup_post(void); +int os_mlock(void); typedef struct timeval qemu_timeval; #define qemu_gettimeofday(tp) gettimeofday(tp, NULL) diff --git a/include/sysemu/os-win32.h b/include/sysemu/os-win32.h index 71f5fa0..bf8523a 100644 --- a/include/sysemu/os-win32.h +++ b/include/sysemu/os-win32.h @@ -106,4 +106,9 @@ static inline bool is_daemonized(void) return false; } +static inline int os_mlock(void) +{ + return -ENOSYS; +} + #endif diff --git a/os-posix.c b/os-posix.c index 5c64518..d39261d 100644 --- a/os-posix.c +++ b/os-posix.c @@ -363,3 +363,15 @@ bool is_daemonized(void) { return daemonize; } + +int os_mlock(void) +{ + int ret = 0; + + ret = mlockall(MCL_CURRENT | MCL_FUTURE); + if (ret < 0) { + perror("mlockall"); + } + + return ret; +} diff --git a/qemu-options.hx b/qemu-options.hx index 06dd565..1ec9541 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -2569,6 +2569,19 @@ STEXI Do not start CPU at startup (you must type 'c' in the monitor). ETEXI +DEF("realtime", HAS_ARG, QEMU_OPTION_realtime, + "-realtime [mlock=on|off]\n" + " run qemu with realtime features\n" + " mlock=on|off controls mlock support (default: on)\n", + QEMU_ARCH_ALL) +STEXI +@item -realtime mlock=on|off +@findex -realtime +Run qemu with realtime features. +mlocking qemu and guest memory can be enabled via @option{mlock=on} +(enabled by default). +ETEXI + DEF("gdb", HAS_ARG, QEMU_OPTION_gdb, \ "-gdb dev wait for gdb connection on 'dev'\n", QEMU_ARCH_ALL) STEXI diff --git a/vl.c b/vl.c index aeed7f4..71bbcf1 100644 --- a/vl.c +++ b/vl.c @@ -521,6 +521,18 @@ static QemuOptsList qemu_tpmdev_opts = { }, }; +static QemuOptsList qemu_realtime_opts = { + .name = "realtime", + .head = QTAILQ_HEAD_INITIALIZER(qemu_realtime_opts.head), + .desc = { + { + .name = "mlock", + .type = QEMU_OPT_BOOL, + }, + { /* end of list */ } + }, +}; + const char *qemu_get_vm_name(void) { return qemu_name; @@ -1420,6 +1432,20 @@ static void smp_parse(const char *optarg) max_cpus = smp_cpus; } +static void configure_realtime(QemuOpts *opts) +{ + bool enable_mlock; + + enable_mlock = qemu_opt_get_bool(opts, "mlock", true); + + if (enable_mlock) { + if (os_mlock() < 0) { + fprintf(stderr, "qemu: locking memory failed\n"); + exit(1); + } + } +} + /***********************************************************/ /* USB devices */ @@ -2909,6 +2935,7 @@ int main(int argc, char **argv, char **envp) qemu_add_opts(&qemu_add_fd_opts); qemu_add_opts(&qemu_object_opts); qemu_add_opts(&qemu_tpmdev_opts); + qemu_add_opts(&qemu_realtime_opts); runstate_init(); @@ -3878,6 +3905,13 @@ int main(int argc, char **argv, char **envp) exit(1); } break; + case QEMU_OPTION_realtime: + opts = qemu_opts_parse(qemu_find_opts("realtime"), optarg, 0); + if (!opts) { + exit(1); + } + configure_realtime(opts); + break; default: os_parse_cmd_args(popt->index, optarg); }