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| author | Nathan Lynch <nathanl@linux.ibm.com> | 2019-04-18 13:56:57 -0500 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2019-04-20 22:03:57 +1000 |
| commit | 2d4d9b308f8f8dec68f6dbbff18c68ec7c6bd26f (patch) | |
| tree | edf44b1690bfcf30ea0284ca38fe35862e9afb84 /arch/powerpc/mm/numa.c | |
| parent | 2f9196b67237f1e59f2753b2968f8ad6433d4042 (diff) | |
| download | linux-2d4d9b308f8f8dec68f6dbbff18c68ec7c6bd26f.tar.gz | |
powerpc/numa: improve control of topology updates
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>
Diffstat (limited to 'arch/powerpc/mm/numa.c')
| -rw-r--r-- | arch/powerpc/mm/numa.c | 18 |
1 files changed, 12 insertions, 6 deletions
diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c index f3ee0e18edd61..952ada44df629 100644 --- a/arch/powerpc/mm/numa.c +++ b/arch/powerpc/mm/numa.c @@ -1497,6 +1497,9 @@ 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; @@ -1530,6 +1533,9 @@ int stop_topology_update(void) { int rc = 0; + if (!topology_updates_enabled) + return 0; + if (prrn_enabled) { prrn_enabled = 0; #ifdef CONFIG_SMP @@ -1587,11 +1593,13 @@ 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; @@ -1606,9 +1614,7 @@ 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 (vphn_enabled) topology_schedule_update(); |