[Qemu-devel] [PATCH 0/2] Document MAX_CPUMASK_BITS and use it when limiting max_cpus

[Qemu-devel] [PATCH 0/2] Document MAX_CPUMASK_BITS and use it when limiting max_cpus

[Eduardo Habkost]

Small rework of patches 6/7 and 7/7 from the previous APIC-ID-limit series I
sent (which broke the build and where reverted).

Instead of renaming MAX_CPUMASK_BITS like I did previously, just document it
and use it on the (max_cpus > 255) check on vl.c.

Eduardo Habkost (2):
  sysemu.h: Document what MAX_CPUMASK_BITS really limits
  vl.c: Use MAX_CPUMASK_BITS macro instead of hardcoded constant

 include/sysemu/sysemu.h | 7 +++++++
 vl.c                    | 2 +-
 2 files changed, 8 insertions(+), 1 deletion(-)

-- 
1.8.5.3

[Qemu-devel] [PATCH 1/2] sysemu.h: Document what MAX_CPUMASK_BITS really limits

[Eduardo Habkost]

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
---
 include/sysemu/sysemu.h | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/include/sysemu/sysemu.h b/include/sysemu/sysemu.h
index c01304d..865e5f0 100644
--- a/include/sysemu/sysemu.h
+++ b/include/sysemu/sysemu.h
@@ -133,7 +133,14 @@ extern uint8_t qemu_extra_params_fw[2];
 extern QEMUClockType rtc_clock;
 
 #define MAX_NODES 64
+
+/* The following shall be true for all CPUs:
+ *   cpu->cpu_index < max_cpus <= MAX_CPUMASK_BITS
+ *
+ * Note that cpu->get_arch_id() may be larger than MAX_CPUMASK_BITS.
+ */
 #define MAX_CPUMASK_BITS 255
+
 extern int nb_numa_nodes;
 extern uint64_t node_mem[MAX_NODES];
 extern unsigned long *node_cpumask[MAX_NODES];
-- 
1.8.5.3

[Qemu-devel] [PATCH 2/2] vl.c: Use MAX_CPUMASK_BITS macro instead of hardcoded constant

[Eduardo Habkost]

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
---
 vl.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/vl.c b/vl.c
index f0fe48b..337f340 100644
--- a/vl.c
+++ b/vl.c
@@ -1418,7 +1418,7 @@ static void smp_parse(QemuOpts *opts)
         max_cpus = smp_cpus;
     }
 
-    if (max_cpus > 255) {
+    if (max_cpus > MAX_CPUMASK_BITS) {
         fprintf(stderr, "Unsupported number of maxcpus\n");
         exit(1);
     }
-- 
1.8.5.3

Re: [Qemu-devel] [PATCH 0/2] Document MAX_CPUMASK_BITS and use it when limiting max_cpus

[Laszlo Ersek]

On 03/18/14 20:29, Eduardo Habkost wrote:
> Small rework of patches 6/7 and 7/7 from the previous APIC-ID-limit series I
> sent (which broke the build and where reverted).
> 
> Instead of renaming MAX_CPUMASK_BITS like I did previously, just document it
> and use it on the (max_cpus > 255) check on vl.c.
> 
> Eduardo Habkost (2):
>   sysemu.h: Document what MAX_CPUMASK_BITS really limits
>   vl.c: Use MAX_CPUMASK_BITS macro instead of hardcoded constant
> 
>  include/sysemu/sysemu.h | 7 +++++++
>  vl.c                    | 2 +-
>  2 files changed, 8 insertions(+), 1 deletion(-)
> 

series
Reviewed-by: Laszlo Ersek <lersek@redhat.com>

Re: [Qemu-devel] [PATCH 0/2] Document MAX_CPUMASK_BITS and use it when limiting max_cpus

[Michael S. Tsirkin]

On Tue, Mar 18, 2014 at 04:29:22PM -0300, Eduardo Habkost wrote:
> Small rework of patches 6/7 and 7/7 from the previous APIC-ID-limit series I
> sent (which broke the build and where reverted).
> 
> Instead of renaming MAX_CPUMASK_BITS like I did previously, just document it
> and use it on the (max_cpus > 255) check on vl.c.


Applied, thanks!

> Eduardo Habkost (2):
>   sysemu.h: Document what MAX_CPUMASK_BITS really limits
>   vl.c: Use MAX_CPUMASK_BITS macro instead of hardcoded constant
> 
>  include/sysemu/sysemu.h | 7 +++++++
>  vl.c                    | 2 +-
>  2 files changed, 8 insertions(+), 1 deletion(-)
> 
> -- 
> 1.8.5.3