diff options
| author | Paul Mackerras <paulus@samba.org> | 2013-08-12 16:29:33 +1000 |
|---|---|---|
| committer | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2013-08-14 15:00:22 +1000 |
| commit | 256f2d4b463d3030ebc8d2b54f427543814a2bdc (patch) | |
| tree | bbf8fb26d8cd8aa154b879eadd503bd5b5a1ffaf | |
| parent | a8a5356cd511db229aeaad636dc0f83d8c4d0a15 (diff) | |
powerpc: Use ibm, chip-id property to compute cpu_core_mask if available
Some systems have an ibm,chip-id property in the cpu nodes in the
device tree. On these systems, we now use that to compute the
cpu_core_mask (i.e. the set of core siblings) rather than looking
at cache properties.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Tested-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| -rw-r--r-- | arch/powerpc/kernel/smp.c | 48 |
1 files changed, 45 insertions, 3 deletions
diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c index 0cc69d5deac9..009900dd8f25 100644 --- a/arch/powerpc/kernel/smp.c +++ b/arch/powerpc/kernel/smp.c @@ -609,6 +609,33 @@ int cpu_first_thread_of_core(int core) } EXPORT_SYMBOL_GPL(cpu_first_thread_of_core); +static void traverse_siblings_chip_id(int cpu, bool add, int chipid) +{ + const struct cpumask *mask; + struct device_node *np; + int i, plen; + const __be32 *prop; + + mask = add ? cpu_online_mask : cpu_present_mask; + for_each_cpu(i, mask) { + np = of_get_cpu_node(i, NULL); + if (!np) + continue; + prop = of_get_property(np, "ibm,chip-id", &plen); + if (prop && plen == sizeof(int) && + of_read_number(prop, 1) == chipid) { + if (add) { + cpumask_set_cpu(cpu, cpu_core_mask(i)); + cpumask_set_cpu(i, cpu_core_mask(cpu)); + } else { + cpumask_clear_cpu(cpu, cpu_core_mask(i)); + cpumask_clear_cpu(i, cpu_core_mask(cpu)); + } + } + of_node_put(np); + } +} + /* Must be called when no change can occur to cpu_present_mask, * i.e. during cpu online or offline. */ @@ -633,14 +660,29 @@ static struct device_node *cpu_to_l2cache(int cpu) static void traverse_core_siblings(int cpu, bool add) { - struct device_node *l2_cache; + struct device_node *l2_cache, *np; const struct cpumask *mask; - int i; + int i, chip, plen; + const __be32 *prop; + + /* First see if we have ibm,chip-id properties in cpu nodes */ + np = of_get_cpu_node(cpu, NULL); + if (np) { + chip = -1; + prop = of_get_property(np, "ibm,chip-id", &plen); + if (prop && plen == sizeof(int)) + chip = of_read_number(prop, 1); + of_node_put(np); + if (chip >= 0) { + traverse_siblings_chip_id(cpu, add, chip); + return; + } + } l2_cache = cpu_to_l2cache(cpu); mask = add ? cpu_online_mask : cpu_present_mask; for_each_cpu(i, mask) { - struct device_node *np = cpu_to_l2cache(i); + np = cpu_to_l2cache(i); if (!np) continue; if (np == l2_cache) { |