On Wed, May 21, 2014 at 12:10 PM, Michael S. Tsirkin <m...@redhat.com> wrote:
> On Tue, May 20, 2014 at 05:15:08PM +0200, Igor Mammedov wrote:
>> Add following parameters:
>> "slots" - total number of hotplug memory slots
>> "maxmem" - maximum possible memory
>>
>> "slots" and "maxmem" should go in pair and "maxmem" should be greater
>> than "mem" for memory hotplug to be enabled.
>>
>> Signed-off-by: Igor Mammedov <imamm...@redhat.com>
>
> Also, it's a bug to mix this with a compat machine type, right?
> Maybe best to fail initialization if users try this.
>
>> ---
>> v4:
>> - store maxmem & slots values in MachineState
>> v3:
>> - store maxmem & slots values in QEMUMachineInitArgs
>> v2:
>> - rebased on top of the latest "vl: convert -m to QemuOpts"
>> ---
>> include/hw/boards.h | 3 ++-
>> qemu-options.hx | 9 ++++++---
>> vl.c | 51
>> +++++++++++++++++++++++++++++++++++++++++++++++++++
>> 3 files changed, 59 insertions(+), 4 deletions(-)
>>
>> diff --git a/include/hw/boards.h b/include/hw/boards.h
>> index b62de4a..f6fbbe1 100644
>> --- a/include/hw/boards.h
>> +++ b/include/hw/boards.h
>> @@ -8,7 +8,6 @@
>> #include "hw/qdev.h"
>> #include "qom/object.h"
>>
>> -
>> typedef struct MachineState MachineState;
>>
>> typedef void QEMUMachineInitFunc(MachineState *ms);
>> @@ -113,6 +112,8 @@ struct MachineState {
>> char *firmware;
>>
>> ram_addr_t ram_size;
>> + ram_addr_t maxram_size;
>> + uint64_t ram_slots;
>> const char *boot_order;
>> const char *kernel_filename;
>> const char *kernel_cmdline;
>> diff --git a/qemu-options.hx b/qemu-options.hx
>> index 781af14..c6411c4 100644
>> --- a/qemu-options.hx
>> +++ b/qemu-options.hx
>> @@ -210,17 +210,20 @@ use is discouraged as it may be removed from future
>> versions.
>> ETEXI
>>
>> DEF("m", HAS_ARG, QEMU_OPTION_m,
>> - "-m [size=]megs\n"
>> + "-m[emory] [size=]megs[,slots=n,maxmem=size]\n"
>> " configure guest RAM\n"
>> " size: initial amount of guest memory (default: "
>> - stringify(DEFAULT_RAM_SIZE) "MiB)\n",
>> + stringify(DEFAULT_RAM_SIZE) "MiB)\n"
>> + " slots: number of hotplug slots (default: none)\n"
>> + " maxmem: maximum amount of guest memory (default:
>> none)\n",
>> QEMU_ARCH_ALL)
>> STEXI
>> @item -m [size=]@var{megs}
>> @findex -m
>> Set virtual RAM size to @var{megs} megabytes. Default is 128 MiB.
>> Optionally,
>> a suffix of ``M'' or ``G'' can be used to signify a value in megabytes or
>> -gigabytes respectively.
>> +gigabytes respectively. Optional pair @var{slots}, @var{maxmem} could be
>> used
>> +to set amount of hotluggable memory slots and possible maximum amount of
>> memory.
>> ETEXI
>>
>> DEF("mem-path", HAS_ARG, QEMU_OPTION_mempath,
>> diff --git a/vl.c b/vl.c
>> index 8fd4ed9..9fb6fa4 100644
>> --- a/vl.c
>> +++ b/vl.c
>> @@ -520,6 +520,14 @@ static QemuOptsList qemu_mem_opts = {
>> .name = "size",
>> .type = QEMU_OPT_SIZE,
>> },
>> + {
>> + .name = "slots",
>> + .type = QEMU_OPT_NUMBER,
>> + },
>> + {
>> + .name = "maxmem",
>> + .type = QEMU_OPT_SIZE,
>> + },
>> { /* end of list */ }
>> },
>> };
>> @@ -2989,6 +2997,8 @@ int main(int argc, char **argv, char **envp)
>> const char *trace_file = NULL;
>> const ram_addr_t default_ram_size = (ram_addr_t)DEFAULT_RAM_SIZE *
>> 1024 * 1024;
>> + ram_addr_t maxram_size = default_ram_size;
>> + uint64_t ram_slots = 0;
>>
>> atexit(qemu_run_exit_notifiers);
>> error_set_progname(argv[0]);
>> @@ -3324,6 +3334,7 @@ int main(int argc, char **argv, char **envp)
>> case QEMU_OPTION_m: {
>> uint64_t sz;
>> const char *mem_str;
>> + const char *maxmem_str, *slots_str;
>>
>> opts = qemu_opts_parse(qemu_find_opts("memory"),
>> optarg, 1);
>> @@ -3365,6 +3376,44 @@ int main(int argc, char **argv, char **envp)
>> error_report("ram size too large");
>> exit(EXIT_FAILURE);
>> }
>> +
>> + maxmem_str = qemu_opt_get(opts, "maxmem");
>> + slots_str = qemu_opt_get(opts, "slots");
>> + if (maxmem_str && slots_str) {
>> + uint64_t slots;
>> +
>> + sz = qemu_opt_get_size(opts, "maxmem", 0);
>> + if (sz < ram_size) {
>> + fprintf(stderr, "qemu: invalid -m option value:
>> maxmem "
>> + "(%" PRIu64 ") <= initial memory (%"
>> + PRIu64 ")\n", sz, ram_size);
>> + exit(EXIT_FAILURE);
>> + }
>> +
>> + slots = qemu_opt_get_number(opts, "slots", 0);
>> + if ((sz > ram_size) && !slots) {
>> + fprintf(stderr, "qemu: invalid -m option value:
>> maxmem "
>> + "(%" PRIu64 ") more than initial memory (%"
>> + PRIu64 ") but no hotplug slots where "
>> + "specified\n", sz, ram_size);
>> + exit(EXIT_FAILURE);
>> + }
>> +
>> + if ((sz <= ram_size) && slots) {
>> + fprintf(stderr, "qemu: invalid -m option value: %"
>> + PRIu64 " hotplug slots where specified but "
>> + "maxmem (%" PRIu64 ") <= initial memory (%"
>> + PRIu64 ")\n", slots, sz, ram_size);
>> + exit(EXIT_FAILURE);
>> + }
>> + maxram_size = sz;
>> + ram_slots = slots;
>> + } else if ((!maxmem_str && slots_str) ||
>> + (maxmem_str && !slots_str)) {
>> + fprintf(stderr, "qemu: invalid -m option value: missing
>> "
>> + "'%s' option\n", slots_str ? "maxmem" :
>> "slots");
>> + exit(EXIT_FAILURE);
>> + }
>> break;
>> }
>> #ifdef CONFIG_TPM
>> @@ -4422,6 +4471,8 @@ int main(int argc, char **argv, char **envp)
>> qdev_machine_init();
>>
>> current_machine->ram_size = ram_size;
>> + current_machine->maxram_size = maxram_size;
>> + current_machine->ram_slots = ram_slots;
>> current_machine->boot_order = boot_order;
>> current_machine->kernel_filename = kernel_filename;
>> current_machine->kernel_cmdline = kernel_cmdline;
>> --
>> 1.7.1
May be I am adding very userish opinion, but ability to specify slot
state via cmdline explicitly, like in
https://github.com/vliaskov/qemu-kvm/tree/memhp-v5-wip, looks better
in sight of thoughts of future integration in libvirt and for unplug
option (where knowledge of which regions are offlined is necessary to
do the job).
