[lvm2-commits] master - dmstats: separate TIMERFD and useleep() exit conditions

Gitweb: http://git.fedorahosted.org/git/?p=lvm2.git;a=commitdiff;h=5635cd3b0337ac... Commit: 5635cd3b0337ac854a82a1a15cef2609c2091e6c Parent: 886b4f755d7f33194f92dafbf2c22517db4de374 Author: Bryn M. Reeves <bmr(a)redhat.com&gt; AuthorDate: Sun Dec 18 12:42:47 2016 +0000 Committer: Bryn M. Reeves <bmr(a)redhat.com&gt; CommitterDate: Sun Dec 18 13:03:44 2016 +0000 dmstats: separate TIMERFD and useleep() exit conditions The time management code mixes tests of the _timer_fd value with code that should be timer agnostic: this causes problems for users of the usleep() timer, since it cannot properly detect the start of a new interval: Beginning first interval Interval #18446744069414584348 time delta: 1000000000ns Interval #18446744069414584348 current err: 0ns End interval #18446744069414584348 duration: 1000000000ns Adjusted sample interval duration: 1000000000ns [...] Beginning first interval Interval #18446744069414584349 time delta: 1000000000ns Interval #18446744069414584349 current err: 0ns End interval #18446744069414584349 duration: 1000000000ns Adjusted sample interval duration: 1000000000ns Separate these out, by defining a _timer_running() call that each timer implements, and only define _timer_fd if we are compiling with TIMERFD enabled. --- tools/dmsetup.c | 19 +++++++++++++++++-- 1 files changed, 17 insertions(+), 2 deletions(-) diff --git a/tools/dmsetup.c b/tools/dmsetup.c index 17c5742..b1967db 100644 --- a/tools/dmsetup.c +++ b/tools/dmsetup.c @@ -286,7 +286,9 @@ static struct dm_timestamp *_start_timestamp = NULL; static uint64_t _interval = 0; /* configured interval in nsecs */ static uint64_t _new_interval = 0; /* flag top-of-interval */ static uint64_t _last_interval = 0; /* approx. measured interval in nsecs */ +#ifdef HAVE_SYS_TIMERFD_H static int _timer_fd = -1; /* timerfd file descriptor. */ +#endif /* HAVE_SYS_TIMERFD_H */ /* Invalid fd value used to signal end-of-reporting. */ #define TIMER_STOPPED -2 @@ -647,6 +649,14 @@ static int _do_timer_wait(void) return _do_timerfd_wait(); } +static int _timer_running(void) +{ + /* + * Clock shutdown for exit - nothing to do. + */ + return ((_timer_fd == TIMER_STOPPED) && !_cycle_timestamp); +} + #else /* !HAVE_SYS_TIMERFD_H */ static int _start_usleep_timer(void) { @@ -718,6 +728,11 @@ static int _do_timer_wait(void) return _do_usleep_wait(); } +static int _timer_running(void) +{ + return (_start_timestamp != NULL); +} + #endif /* HAVE_SYS_TIMERFD_H */ static int _update_interval_times(void) @@ -729,7 +744,7 @@ static int _update_interval_times(void) /* * Clock shutdown for exit - nothing to do. */ - if ((_timer_fd == TIMER_STOPPED) && !_cycle_timestamp) + if (!_timer_running()) goto out; /* clock is running */ @@ -805,7 +820,7 @@ static int _update_interval_times(void) out: /* timer stopped or never started */ - if (!r || _timer_fd < 0) { + if (!r || !_timer_running()) { /* The _cycle_timestamp has not yet been allocated if we * fail to obtain this_timestamp on the first interval. */