(To be applied after Jose reorganization patch)
This patch fixes a potential infinite loop while finding the
BT/system clock read latency. If the adapter is removed exactly
at that moment, BT clock simply can't be read and it must quit.
This is handled as a temporary failure (if a new connection is
made, adapter is probably in place again).
---
health/mcap_sync.c | 46 ++++++++++++++++++++++++++++++++++++++++------
1 files changed, 40 insertions(+), 6 deletions(-)
diff --git a/health/mcap_sync.c b/health/mcap_sync.c
index 0943e41..670260b 100644
--- a/health/mcap_sync.c
+++ b/health/mcap_sync.c
@@ -360,7 +360,7 @@ uint32_t mcap_get_btclock(struct mcap_mcl *mcl)
return btclock;
}
-static void initialize_caps(struct mcap_mcl *mcl)
+static gboolean initialize_caps(struct mcap_mcl *mcl)
{
struct timespec t1, t2;
int latencies[20];
@@ -368,6 +368,7 @@ static void initialize_caps(struct mcap_mcl *mcl)
uint32_t btclock;
uint16_t btaccuracy;
int i;
+ int retries;
clock_getres(CLK, &t1);
@@ -383,10 +384,12 @@ static void initialize_caps(struct mcap_mcl *mcl)
/* Do clock read a number of times and measure latency */
avg = 0;
- for (i = 0; i < 20; ++i) {
+ retries = 10;
+ for (i = 0; i < 20 && retries > 0; ++i) {
clock_gettime(CLK, &t1);
if (!read_btclock(mcl, &btclock, &btaccuracy)) {
--i;
+ --retries;
continue;
}
clock_gettime(CLK, &t2);
@@ -395,9 +398,12 @@ static void initialize_caps(struct mcap_mcl *mcl)
latencies[i] = latency;
avg += latency;
}
- avg /= 20;
- /* Calculate deviation */
+ if (retries <= 0)
+ return FALSE;
+
+ /* Calculate average and deviation */
+ avg /= 20;
dev = 0;
for (i = 0; i < 20; ++i)
dev += abs(latencies[i] - avg);
@@ -418,12 +424,16 @@ static void initialize_caps(struct mcap_mcl *mcl)
_caps.syncleadtime_ms = latency * 50 / 1000;
csp_caps_initialized = TRUE;
+ return TRUE;
}
static struct csp_caps *caps(struct mcap_mcl *mcl)
{
if (!csp_caps_initialized)
- initialize_caps(mcl);
+ if (!initialize_caps(mcl)) {
+ /* Temporary failure in reading BT clock */
+ return NULL;
+ }
return &_caps;
}
@@ -465,6 +475,12 @@ static void proc_sync_cap_req(struct mcap_mcl *mcl, uint8_t *cmd, uint32_t len)
return;
}
+ if (!caps(mcl)) {
+ send_sync_cap_rsp(mcl, MCAP_RESOURCE_UNAVAILABLE,
+ 0, 0, 0, 0);
+ return;
+ }
+
req = (mcap_md_sync_cap_req *) cmd;
required_accuracy = ntohs(req->timest);
our_accuracy = caps(mcl)->ts_acc;
@@ -514,11 +530,16 @@ static gboolean get_all_clocks(struct mcap_mcl *mcl, uint32_t *btclock,
struct timespec *base_time,
uint64_t *timestamp)
{
- int latency = caps(mcl)->preempt_thresh + 1;
+ int latency;
int retry = 5;
uint16_t btres;
struct timespec t0;
+ if (!caps(mcl))
+ return FALSE;
+
+ latency = caps(mcl)->preempt_thresh + 1;
+
while (latency > caps(mcl)->preempt_thresh && --retry >= 0) {
clock_gettime(CLK, &t0);
@@ -553,6 +574,9 @@ static gboolean sync_send_indication(gpointer user_data)
mcl = user_data;
+ if (!caps(mcl))
+ return FALSE;
+
if (!get_all_clocks(mcl, &btclock, &base_time, &tmstamp))
return FALSE;
@@ -600,6 +624,11 @@ static gboolean proc_sync_set_req_phase2(gpointer user_data)
ind_freq = data->ind_freq;
role = data->role;
+ if (!caps(mcl)) {
+ send_sync_set_rsp(mcl, MCAP_UNSPECIFIED_ERROR, 0, 0, 0);
+ return FALSE;
+ }
+
if (!get_all_clocks(mcl, &btclock, &base_time, &tmstamp)) {
send_sync_set_rsp(mcl, MCAP_UNSPECIFIED_ERROR, 0, 0, 0);
return FALSE;
@@ -688,6 +717,11 @@ static void proc_sync_set_req(struct mcap_mcl *mcl, uint8_t *cmd, uint32_t len)
return;
}
+ if (!caps(mcl)) {
+ send_sync_set_rsp(mcl, MCAP_UNSPECIFIED_ERROR, 0, 0, 0);
+ return;
+ }
+
if (!read_btclock_retry(mcl, &cur_btclock, &btres)) {
send_sync_set_rsp(mcl, MCAP_UNSPECIFIED_ERROR, 0, 0, 0);
return;
--
1.7.0.4
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