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authorDavid S. Miller <davem@davemloft.net>2020-08-27 12:55:46 -0700
committerDavid S. Miller <davem@davemloft.net>2020-08-27 12:55:46 -0700
commit8d73a73a7f6312e65f3c93b6cb93df9e1eff2ca1 (patch)
treee98531ed23db31f49b2f75298f983082c47d98aa /fs/afs
parentaf8ea111134624855710a0ef5543b871d49b0162 (diff)
parente4686c79b103c0a73b8ed41e5fd967da201b6fba (diff)
Merge tag 'rxrpc-fixes-20200820' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs
David Howells says: ==================== rxrpc, afs: Fix probing issues Here are some fixes for rxrpc and afs to fix issues in the RTT measuring in rxrpc and thence the Volume Location server probing in afs: (1) Move the serial number of a received ACK into a local variable to simplify the next patch. (2) Fix the loss of RTT samples due to extra interposed ACKs causing baseline information to be discarded too early. This is a particular problem for afs when it sends a single very short call to probe a server it hasn't talked to recently. (3) Fix rxrpc_kernel_get_srtt() to indicate whether it actually has seen any valid samples or not. (4) Remove a field that's set/woken, but never read/waited on. (5) Expose the RTT and other probe information through procfs to make debugging of this stuff easier. (6) Fix VL rotation in afs to only use summary information from VL probing and not the probe running state (which gets clobbered when next a probe is issued). (7) Fix VL rotation to actually return the error aggregated from the probe errors. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'fs/afs')
-rw-r--r--fs/afs/fs_probe.c4
-rw-r--r--fs/afs/internal.h14
-rw-r--r--fs/afs/proc.c5
-rw-r--r--fs/afs/vl_list.c1
-rw-r--r--fs/afs/vl_probe.c82
-rw-r--r--fs/afs/vl_rotate.c7
6 files changed, 73 insertions, 40 deletions
diff --git a/fs/afs/fs_probe.c b/fs/afs/fs_probe.c
index 5d9ef517cf81..e7e98ad63a91 100644
--- a/fs/afs/fs_probe.c
+++ b/fs/afs/fs_probe.c
@@ -161,8 +161,8 @@ responded:
}
}
- rtt_us = rxrpc_kernel_get_srtt(call->net->socket, call->rxcall);
- if (rtt_us < server->probe.rtt) {
+ if (rxrpc_kernel_get_srtt(call->net->socket, call->rxcall, &rtt_us) &&
+ rtt_us < server->probe.rtt) {
server->probe.rtt = rtt_us;
server->rtt = rtt_us;
alist->preferred = index;
diff --git a/fs/afs/internal.h b/fs/afs/internal.h
index 792ac711985e..18042b7dab6a 100644
--- a/fs/afs/internal.h
+++ b/fs/afs/internal.h
@@ -401,22 +401,24 @@ struct afs_vlserver {
#define AFS_VLSERVER_FL_PROBED 0 /* The VL server has been probed */
#define AFS_VLSERVER_FL_PROBING 1 /* VL server is being probed */
#define AFS_VLSERVER_FL_IS_YFS 2 /* Server is YFS not AFS */
+#define AFS_VLSERVER_FL_RESPONDING 3 /* VL server is responding */
rwlock_t lock; /* Lock on addresses */
atomic_t usage;
+ unsigned int rtt; /* Server's current RTT in uS */
/* Probe state */
wait_queue_head_t probe_wq;
atomic_t probe_outstanding;
spinlock_t probe_lock;
struct {
- unsigned int rtt; /* RTT as ktime/64 */
+ unsigned int rtt; /* RTT in uS */
u32 abort_code;
short error;
- bool have_result;
- bool responded:1;
- bool is_yfs:1;
- bool not_yfs:1;
- bool local_failure:1;
+ unsigned short flags;
+#define AFS_VLSERVER_PROBE_RESPONDED 0x01 /* At least once response (may be abort) */
+#define AFS_VLSERVER_PROBE_IS_YFS 0x02 /* The peer appears to be YFS */
+#define AFS_VLSERVER_PROBE_NOT_YFS 0x04 /* The peer appears not to be YFS */
+#define AFS_VLSERVER_PROBE_LOCAL_FAILURE 0x08 /* A local failure prevented a probe */
} probe;
u16 port;
diff --git a/fs/afs/proc.c b/fs/afs/proc.c
index e817fc740ba0..e8babb62ed44 100644
--- a/fs/afs/proc.c
+++ b/fs/afs/proc.c
@@ -310,6 +310,11 @@ static int afs_proc_cell_vlservers_show(struct seq_file *m, void *v)
alist->preferred == i ? '>' : '-',
&alist->addrs[i].transport);
}
+ seq_printf(m, " info: fl=%lx rtt=%d\n", vlserver->flags, vlserver->rtt);
+ seq_printf(m, " probe: fl=%x e=%d ac=%d out=%d\n",
+ vlserver->probe.flags, vlserver->probe.error,
+ vlserver->probe.abort_code,
+ atomic_read(&vlserver->probe_outstanding));
return 0;
}
diff --git a/fs/afs/vl_list.c b/fs/afs/vl_list.c
index 8fea54eba0c2..38b2ba1d9ec0 100644
--- a/fs/afs/vl_list.c
+++ b/fs/afs/vl_list.c
@@ -21,6 +21,7 @@ struct afs_vlserver *afs_alloc_vlserver(const char *name, size_t name_len,
rwlock_init(&vlserver->lock);
init_waitqueue_head(&vlserver->probe_wq);
spin_lock_init(&vlserver->probe_lock);
+ vlserver->rtt = UINT_MAX;
vlserver->name_len = name_len;
vlserver->port = port;
memcpy(vlserver->name, name, name_len);
diff --git a/fs/afs/vl_probe.c b/fs/afs/vl_probe.c
index e3aa013c2177..d1c7068b4346 100644
--- a/fs/afs/vl_probe.c
+++ b/fs/afs/vl_probe.c
@@ -11,15 +11,33 @@
#include "internal.h"
#include "protocol_yfs.h"
-static bool afs_vl_probe_done(struct afs_vlserver *server)
+
+/*
+ * Handle the completion of a set of probes.
+ */
+static void afs_finished_vl_probe(struct afs_vlserver *server)
{
- if (!atomic_dec_and_test(&server->probe_outstanding))
- return false;
+ if (!(server->probe.flags & AFS_VLSERVER_PROBE_RESPONDED)) {
+ server->rtt = UINT_MAX;
+ clear_bit(AFS_VLSERVER_FL_RESPONDING, &server->flags);
+ }
- wake_up_var(&server->probe_outstanding);
clear_bit_unlock(AFS_VLSERVER_FL_PROBING, &server->flags);
wake_up_bit(&server->flags, AFS_VLSERVER_FL_PROBING);
- return true;
+}
+
+/*
+ * Handle the completion of a probe RPC call.
+ */
+static void afs_done_one_vl_probe(struct afs_vlserver *server, bool wake_up)
+{
+ if (atomic_dec_and_test(&server->probe_outstanding)) {
+ afs_finished_vl_probe(server);
+ wake_up = true;
+ }
+
+ if (wake_up)
+ wake_up_all(&server->probe_wq);
}
/*
@@ -45,15 +63,20 @@ void afs_vlserver_probe_result(struct afs_call *call)
server->probe.error = 0;
goto responded;
case -ECONNABORTED:
- if (!server->probe.responded) {
+ if (!(server->probe.flags & AFS_VLSERVER_PROBE_RESPONDED)) {
server->probe.abort_code = call->abort_code;
server->probe.error = ret;
}
goto responded;
case -ENOMEM:
case -ENONET:
- server->probe.local_failure = true;
- afs_io_error(call, afs_io_error_vl_probe_fail);
+ case -EKEYEXPIRED:
+ case -EKEYREVOKED:
+ case -EKEYREJECTED:
+ server->probe.flags |= AFS_VLSERVER_PROBE_LOCAL_FAILURE;
+ if (server->probe.error == 0)
+ server->probe.error = ret;
+ trace_afs_io_error(call->debug_id, ret, afs_io_error_vl_probe_fail);
goto out;
case -ECONNRESET: /* Responded, but call expired. */
case -ERFKILL:
@@ -67,12 +90,12 @@ void afs_vlserver_probe_result(struct afs_call *call)
default:
clear_bit(index, &alist->responded);
set_bit(index, &alist->failed);
- if (!server->probe.responded &&
+ if (!(server->probe.flags & AFS_VLSERVER_PROBE_RESPONDED) &&
(server->probe.error == 0 ||
server->probe.error == -ETIMEDOUT ||
server->probe.error == -ETIME))
server->probe.error = ret;
- afs_io_error(call, afs_io_error_vl_probe_fail);
+ trace_afs_io_error(call->debug_id, ret, afs_io_error_vl_probe_fail);
goto out;
}
@@ -81,39 +104,36 @@ responded:
clear_bit(index, &alist->failed);
if (call->service_id == YFS_VL_SERVICE) {
- server->probe.is_yfs = true;
+ server->probe.flags |= AFS_VLSERVER_PROBE_IS_YFS;
set_bit(AFS_VLSERVER_FL_IS_YFS, &server->flags);
alist->addrs[index].srx_service = call->service_id;
} else {
- server->probe.not_yfs = true;
- if (!server->probe.is_yfs) {
+ server->probe.flags |= AFS_VLSERVER_PROBE_NOT_YFS;
+ if (!(server->probe.flags & AFS_VLSERVER_PROBE_IS_YFS)) {
clear_bit(AFS_VLSERVER_FL_IS_YFS, &server->flags);
alist->addrs[index].srx_service = call->service_id;
}
}
- rtt_us = rxrpc_kernel_get_srtt(call->net->socket, call->rxcall);
- if (rtt_us < server->probe.rtt) {
+ if (rxrpc_kernel_get_srtt(call->net->socket, call->rxcall, &rtt_us) &&
+ rtt_us < server->probe.rtt) {
server->probe.rtt = rtt_us;
+ server->rtt = rtt_us;
alist->preferred = index;
- have_result = true;
}
smp_wmb(); /* Set rtt before responded. */
- server->probe.responded = true;
+ server->probe.flags |= AFS_VLSERVER_PROBE_RESPONDED;
set_bit(AFS_VLSERVER_FL_PROBED, &server->flags);
+ set_bit(AFS_VLSERVER_FL_RESPONDING, &server->flags);
+ have_result = true;
out:
spin_unlock(&server->probe_lock);
_debug("probe [%u][%u] %pISpc rtt=%u ret=%d",
server_index, index, &alist->addrs[index].transport, rtt_us, ret);
- have_result |= afs_vl_probe_done(server);
- if (have_result) {
- server->probe.have_result = true;
- wake_up_var(&server->probe.have_result);
- wake_up_all(&server->probe_wq);
- }
+ afs_done_one_vl_probe(server, have_result);
}
/*
@@ -151,11 +171,10 @@ static bool afs_do_probe_vlserver(struct afs_net *net,
in_progress = true;
} else {
afs_prioritise_error(_e, PTR_ERR(call), ac.abort_code);
+ afs_done_one_vl_probe(server, false);
}
}
- if (!in_progress)
- afs_vl_probe_done(server);
return in_progress;
}
@@ -193,7 +212,7 @@ int afs_wait_for_vl_probes(struct afs_vlserver_list *vllist,
{
struct wait_queue_entry *waits;
struct afs_vlserver *server;
- unsigned int rtt = UINT_MAX;
+ unsigned int rtt = UINT_MAX, rtt_s;
bool have_responders = false;
int pref = -1, i;
@@ -205,7 +224,7 @@ int afs_wait_for_vl_probes(struct afs_vlserver_list *vllist,
server = vllist->servers[i].server;
if (!test_bit(AFS_VLSERVER_FL_PROBING, &server->flags))
__clear_bit(i, &untried);
- if (server->probe.responded)
+ if (server->probe.flags & AFS_VLSERVER_PROBE_RESPONDED)
have_responders = true;
}
}
@@ -231,7 +250,7 @@ int afs_wait_for_vl_probes(struct afs_vlserver_list *vllist,
for (i = 0; i < vllist->nr_servers; i++) {
if (test_bit(i, &untried)) {
server = vllist->servers[i].server;
- if (server->probe.responded)
+ if (server->probe.flags & AFS_VLSERVER_PROBE_RESPONDED)
goto stop;
if (test_bit(AFS_VLSERVER_FL_PROBING, &server->flags))
still_probing = true;
@@ -249,10 +268,11 @@ stop:
for (i = 0; i < vllist->nr_servers; i++) {
if (test_bit(i, &untried)) {
server = vllist->servers[i].server;
- if (server->probe.responded &&
- server->probe.rtt < rtt) {
+ rtt_s = READ_ONCE(server->rtt);
+ if (test_bit(AFS_VLSERVER_FL_RESPONDING, &server->flags) &&
+ rtt_s < rtt) {
pref = i;
- rtt = server->probe.rtt;
+ rtt = rtt_s;
}
remove_wait_queue(&server->probe_wq, &waits[i]);
diff --git a/fs/afs/vl_rotate.c b/fs/afs/vl_rotate.c
index f405ca8b240a..c0458c903b31 100644
--- a/fs/afs/vl_rotate.c
+++ b/fs/afs/vl_rotate.c
@@ -192,7 +192,8 @@ pick_server:
for (i = 0; i < vc->server_list->nr_servers; i++) {
struct afs_vlserver *s = vc->server_list->servers[i].server;
- if (!test_bit(i, &vc->untried) || !s->probe.responded)
+ if (!test_bit(i, &vc->untried) ||
+ !test_bit(AFS_VLSERVER_FL_RESPONDING, &s->flags))
continue;
if (s->probe.rtt < rtt) {
vc->index = i;
@@ -262,10 +263,14 @@ no_more_servers:
for (i = 0; i < vc->server_list->nr_servers; i++) {
struct afs_vlserver *s = vc->server_list->servers[i].server;
+ if (test_bit(AFS_VLSERVER_FL_RESPONDING, &s->flags))
+ e.responded = true;
afs_prioritise_error(&e, READ_ONCE(s->probe.error),
s->probe.abort_code);
}
+ error = e.error;
+
failed_set_error:
vc->error = error;
failed: