diff options
| author | Nathan Lynch <nathanl@linux.ibm.com> | 2019-04-18 21:56:57 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-05-31 16:47:25 +0300 |
| commit | 667890535fc5990320cb91961bbf7c97a6ed17f8 (patch) | |
| tree | 949ae2daea611765de3e521eee99d1ac5722efb5 /arch/powerpc/mm | |
| parent | 9449e18774aec49f7fd52b5afb15c8d47be7590a (diff) | |
| download | linux-667890535fc5990320cb91961bbf7c97a6ed17f8.tar.xz | |
powerpc/numa: improve control of topology updates
[ 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>
Diffstat (limited to 'arch/powerpc/mm')
| -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 0a02c73a27b3..417ea6db7b1d 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; |