[PATCH 10/25] staging: lustre: libcfs: provide debugfs files for distance handling

From: James Simmons
Date: Mon Apr 16 2018 - 00:13:58 EST


From: Amir Shehata <amir.shehata@xxxxxxxxx>

On systems with large number of NUMA nodes and cores it is easy
to incorrectly configure their use with Lustre. Provide debugfs
files which can help track down any issues.

Signed-off-by: Amir Shehata <amir.shehata@xxxxxxxxx>
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-7734
Reviewed-on: http://review.whamcloud.com/18916
Reviewed-by: Olaf Weber <olaf@xxxxxxx>
Reviewed-by: Doug Oucharek <dougso@xxxxxx>
Signed-off-by: James Simmons <jsimmons@xxxxxxxxxxxxx>
---
drivers/staging/lustre/lnet/libcfs/module.c | 53 +++++++++++++++++++++++++++++
1 file changed, 53 insertions(+)

diff --git a/drivers/staging/lustre/lnet/libcfs/module.c b/drivers/staging/lustre/lnet/libcfs/module.c
index a03f924..95af000 100644
--- a/drivers/staging/lustre/lnet/libcfs/module.c
+++ b/drivers/staging/lustre/lnet/libcfs/module.c
@@ -336,6 +336,53 @@ static int proc_cpt_table(struct ctl_table *table, int write,
__proc_cpt_table);
}

+static int __proc_cpt_distance(void *data, int write,
+ loff_t pos, void __user *buffer, int nob)
+{
+ char *buf = NULL;
+ int len = 4096;
+ int rc = 0;
+
+ if (write)
+ return -EPERM;
+
+ LASSERT(cfs_cpt_table);
+
+ while (1) {
+ buf = kzalloc(len, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ rc = cfs_cpt_distance_print(cfs_cpt_table, buf, len);
+ if (rc >= 0)
+ break;
+
+ if (rc == -EFBIG) {
+ kfree(buf);
+ len <<= 1;
+ continue;
+ }
+ goto out;
+ }
+
+ if (pos >= rc) {
+ rc = 0;
+ goto out;
+ }
+
+ rc = cfs_trace_copyout_string(buffer, nob, buf + pos, NULL);
+out:
+ kfree(buf);
+ return rc;
+}
+
+static int proc_cpt_distance(struct ctl_table *table, int write,
+ void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+ return lprocfs_call_handler(table->data, write, ppos, buffer, lenp,
+ __proc_cpt_distance);
+}
+
static struct ctl_table lnet_table[] = {
{
.procname = "debug",
@@ -365,6 +412,12 @@ static int proc_cpt_table(struct ctl_table *table, int write,
.proc_handler = &proc_cpt_table,
},
{
+ .procname = "cpu_partition_distance",
+ .maxlen = 128,
+ .mode = 0444,
+ .proc_handler = &proc_cpt_distance,
+ },
+ {
.procname = "debug_log_upcall",
.data = lnet_debug_log_upcall,
.maxlen = sizeof(lnet_debug_log_upcall),
--
1.8.3.1