[ Upstream commit 2d4d9b308f8f8dec68f6dbbff18c68ec7c6bd26f ]
When booted with "topology_updates=no", or when "off" is written to /proc/powerpc/topology_updates, NUMA reassignments are inhibited for PRRN and VPHN events. However, migration and suspend unconditionally re-enable reassignments via start_topology_update(). This is incoherent.
Check the topology_updates_enabled flag in start/stop_topology_update() so that callers of those APIs need not be aware of whether reassignments are enabled. This allows the administrative decision on reassignments to remain in force across migrations and suspensions.
Signed-off-by: Nathan Lynch nathanl@linux.ibm.com Signed-off-by: Michael Ellerman mpe@ellerman.id.au Signed-off-by: Sasha Levin sashal@kernel.org --- arch/powerpc/mm/numa.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-)
diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c index 0a02c73a27b3c..417ea6db7b1d2 100644 --- a/arch/powerpc/mm/numa.c +++ b/arch/powerpc/mm/numa.c @@ -1561,6 +1561,9 @@ int start_topology_update(void) { int rc = 0;
+ if (!topology_updates_enabled) + return 0; + if (firmware_has_feature(FW_FEATURE_PRRN)) { if (!prrn_enabled) { prrn_enabled = 1; @@ -1590,6 +1593,9 @@ int stop_topology_update(void) { int rc = 0;
+ if (!topology_updates_enabled) + return 0; + if (prrn_enabled) { prrn_enabled = 0; #ifdef CONFIG_SMP @@ -1635,11 +1641,13 @@ static ssize_t topology_write(struct file *file, const char __user *buf,
kbuf[read_len] = '\0';
- if (!strncmp(kbuf, "on", 2)) + if (!strncmp(kbuf, "on", 2)) { + topology_updates_enabled = true; start_topology_update(); - else if (!strncmp(kbuf, "off", 3)) + } else if (!strncmp(kbuf, "off", 3)) { stop_topology_update(); - else + topology_updates_enabled = false; + } else return -EINVAL;
return count; @@ -1654,9 +1662,7 @@ static const struct file_operations topology_ops = {
static int topology_update_init(void) { - /* Do not poll for changes if disabled at boot */ - if (topology_updates_enabled) - start_topology_update(); + start_topology_update();
if (!proc_create("powerpc/topology_updates", 0644, NULL, &topology_ops)) return -ENOMEM;