perf_event_open.2: wfix

Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>

man2/perf_event_open.2

@@ -707,7 +707,7 @@ a profile.
 .\" commit d6be9ad6c960f43800a6f118932bc8a5a4eadcd1
 Records the data source: where in the memory hierarchy
 the data associated with the sampled instruction came from.
-This is only available if the underlying hardware
+This is available only if the underlying hardware
 supports this feature.
 .TP
 .BR PERF_SAMPLE_IDENTIFIER " (since Linux 3.12)"
@@ -1060,7 +1060,7 @@ Which one is used is selected by the
 bit flag.
 
 .I wakeup_events
-only counts
+counts only
 .B PERF_RECORD_SAMPLE
 record types.
 To receive overflow notification for all
@@ -1295,7 +1295,7 @@ values can be used to scale an estimated value for the count.
 An unsigned 64-bit value containing the counter result.
 .TP
 .I id
-A globally unique value for this particular event, only there if
+A globally unique value for this particular event, only present if
 .B PERF_FORMAT_ID
 was specified in
 .IR read_format .
@@ -2325,7 +2325,7 @@ the event configured with
 .BR fcntl (2)
 to generate SIGIO signals.
 
-Overflows are only generated by sampling events
+Overflows are generated only by sampling events
 .RI ( sample_period
 must have a nonzero value).
 
@@ -2499,7 +2499,7 @@ The
 file can be set to restrict access to the performance counters.
 .RS
 .IP 2 4
-only allow user-space measurements.
+allow only user-space measurements.
 .IP 1
 allow both kernel and user measurements (default).
 .IP 0