dumpstate: only poll 30s for initial data
Before this patch, dumpstate will poll an fd for 30s per line. If the
fd blocks on poll, then this inserts a 30s sleep, which is bad.
After this patch, dumpstate will poll an fd for 30s only for the
initial read of the fd. All subsequent reads of that fd will return
immediately, and as soon as the fd does not have any available data to
read, the polling will cease.
Test: bug reports work and don't time out on /dev/trusty-log0
Bug: 238220830
Change-Id: Ie34cebac62608a914477978704fef813372a273d
diff --git a/cmds/dumpstate/DumpstateInternal.cpp b/cmds/dumpstate/DumpstateInternal.cpp
index 3091f6b..6f7fea3 100644
--- a/cmds/dumpstate/DumpstateInternal.cpp
+++ b/cmds/dumpstate/DumpstateInternal.cpp
@@ -162,17 +162,16 @@
return 0;
}
bool newline = false;
+ int poll_timeout_ms = 30 * 1000;
while (true) {
- uint64_t start_time = Nanotime();
pollfd fds[] = { { .fd = fd, .events = POLLIN } };
- int ret = TEMP_FAILURE_RETRY(poll(fds, arraysize(fds), 30 * 1000));
+ int ret = TEMP_FAILURE_RETRY(poll(fds, arraysize(fds), poll_timeout_ms));
if (ret == -1) {
dprintf(out_fd, "*** %s: poll failed: %s\n", path, strerror(errno));
newline = true;
break;
- } else if (ret == 0) {
- uint64_t elapsed = Nanotime() - start_time;
- dprintf(out_fd, "*** %s: Timed out after %.3fs\n", path, (float)elapsed / NANOS_PER_SEC);
+ } else if (ret == 0 && poll_timeout_ms != 0) {
+ dprintf(out_fd, "*** %s: Timed out after %ds\n", path, poll_timeout_ms / 1000 );
newline = true;
break;
} else {
@@ -189,6 +188,7 @@
break;
}
}
+ poll_timeout_ms = 0;
}
if (!newline) dprintf(out_fd, "\n");