[PATCH 1/2] arm64: use num_possible_cpus() instead of NR_CPUS
Jingoo Han
jg1.han at samsung.com
Wed Jan 29 00:31:11 EST 2014
On Tuesday, January 28, 2014 7:11 PM, Sudeep Holla wrote:
> On 28/01/14 01:35, Jingoo Han wrote:
> > Use num_possible_cpus() instead of direct use of NR_CPUS. Also,
> > it fixes the following checkpatch warning.
> >
> > WARNING: usage of NR_CPUS is often wrong - consider using cpu_possible(), num_possible_cpus(),
> for_each_possible_cpu(), etc
> >
> > Signed-off-by: Jingoo Han <jg1.han at samsung.com>
> > ---
> > arch/arm64/kernel/smp.c | 10 +++++-----
> > arch/arm64/mm/context.c | 2 +-
> > 2 files changed, 6 insertions(+), 6 deletions(-)
> >
> > diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
> > index 1b7617a..09ff7d4 100644
> > --- a/arch/arm64/kernel/smp.c
> > +++ b/arch/arm64/kernel/smp.c
> > @@ -320,7 +320,7 @@ void __init smp_init_cpus(void)
> > * cpu_logical_map was initialized to INVALID_HWID to
> > * avoid matching valid MPIDR values.
> > */
> > - for (i = 1; (i < cpu) && (i < NR_CPUS); i++) {
> > + for (i = 1; (i < cpu) && (i < num_possible_cpus()); i++) {
> > if (cpu_logical_map(i) == hwid) {
> > pr_err("%s: duplicate cpu reg properties in the DT\n",
> > dn->full_name);
> > @@ -352,7 +352,7 @@ void __init smp_init_cpus(void)
> > continue;
> > }
> >
> > - if (cpu >= NR_CPUS)
> > + if (cpu >= num_possible_cpus())
>
> Have you tested this patch ? IIUC this will not work as cpu_possible mask is
> populated completely and correctly only at the end of this function.
>
> > goto next;
> >
> > if (cpu_read_ops(dn, cpu) != 0)
> > @@ -368,9 +368,9 @@ next:
> > }
> >
> > /* sanity check */
> > - if (cpu > NR_CPUS)
> > + if (cpu > num_possible_cpus())
> > pr_warning("no. of cores (%d) greater than configured maximum of %d - clipping\n",
> > - cpu, NR_CPUS);
> > + cpu, num_possible_cpus());
> >
> > if (!bootcpu_valid) {
> > pr_err("DT missing boot CPU MPIDR, not enabling secondaries\n");
> > @@ -381,7 +381,7 @@ next:
> > * All the cpus that made it to the cpu_logical_map have been
> > * validated so set them as possible cpus.
> > */
> > - for (i = 0; i < NR_CPUS; i++)
> > + for (i = 0; i < num_possible_cpus(); i++)
> > if (cpu_logical_map(i) != INVALID_HWID)
> > set_cpu_possible(i, true);
>
> This is what I am referring above, where is possible mask set before this.
> If it's already populated correctly then we can remove this completely.
OK, you're right.
Please, ignore this patch.
I really appreciate your comment. :-)
Best regards,
Jingoo Han
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