Add a flush of the current PMC log buffer before displaying the next top.

As the underlying block is 4KB if the PMC throughput is low the measurement
will be reported on the next tick. pmcstat(8) use the modified flush API to
reclaim current buffer before displaying next top.

MFC after:	1 month

4 files changed, 21 insertions, 1 deletions

diff --git a/lib/libpmc/libpmc.c b/lib/libpmc/libpmc.c
index 1d86a82..f0d5b0c 100644
--- a/lib/libpmc/libpmc.c
+++ b/lib/libpmc/libpmc.c
@@ -2596,6 +2596,12 @@ pmc_flush_logfile(void)
 }
 
 int
+pmc_close_logfile(void)
+{
+	return (PMC_CALL(CLOSELOG,0));
+}
+
+int
 pmc_get_driver_stats(struct pmc_driverstats *ds)
 {
 	struct pmc_op_getdriverstats gms;
diff --git a/lib/libpmc/pmc.3 b/lib/libpmc/pmc.3
index 2403e64..2431080 100644
--- a/lib/libpmc/pmc.3
+++ b/lib/libpmc/pmc.3
@@ -322,6 +322,10 @@ to write logged events to.
 Flush all pending log data in
 .Xr hwpmc 4 Ns Ap s
 buffers.
+.It Fn pmc_close_logfile
+Flush all pending log data and close
+.Xr hwpmc 4 Ns Ap s
+side of the stream.
 .It Fn pmc_writelog
 Append arbitrary user data to the current log file.
 .El
diff --git a/lib/libpmc/pmc.h b/lib/libpmc/pmc.h
index 5b1ad07..2be88b1 100644
--- a/lib/libpmc/pmc.h
+++ b/lib/libpmc/pmc.h
@@ -76,6 +76,7 @@ int	pmc_attach(pmc_id_t _pmcid, pid_t _pid);
 int	pmc_capabilities(pmc_id_t _pmc, uint32_t *_caps);
 int	pmc_configure_logfile(int _fd);
 int	pmc_flush_logfile(void);
+int	pmc_close_logfile(void);
 int	pmc_detach(pmc_id_t _pmcid, pid_t _pid);
 int	pmc_disable(int _cpu, int _pmc);
 int	pmc_enable(int _cpu, int _pmc);
diff --git a/lib/libpmc/pmc_configure_logfile.3 b/lib/libpmc/pmc_configure_logfile.3
index a33688c..399f21a 100644
--- a/lib/libpmc/pmc_configure_logfile.3
+++ b/lib/libpmc/pmc_configure_logfile.3
@@ -29,7 +29,8 @@
 .Sh NAME
 .Nm pmc_configure_logfile ,
 .Nm pmc_flush_logfile ,
-.Nm pmc_writelog
+.Nm pmc_writelog ,
+.Nm pmc_close_logfile
 .Nd log file management
 .Sh LIBRARY
 .Lb libpmc
@@ -41,6 +42,8 @@
 .Fn pmc_flush_logfile void
 .Ft int
 .Fn pmc_writelog "uint32_t userdata"
+.Ft int
+.Fn pmc_close_logfile void
 .Sh DESCRIPTION
 The functions manage logging of
 .Xr hwpmc 4
@@ -72,6 +75,12 @@ Function
 will append a log entry containing the value of argument
 .Fa userdata
 to the log file.
+.Pp
+Function
+.Fn pmc_close_logfile
+will flush all pending log data and close
+.Xr hwpmc 4 Ns Ap s
+side of the stream.
 .Sh RETURN VALUES
 .Rv -std
 .Sh ERRORS