[tip:perfcounters/core] perf_counter tools: remove glib dependency and fix bugs in kerneltop.c, fix poll()

[Peter Zijlstra]

Commit-ID:  afc2a3523fc6664f3713b594daa1857f37ad87df
Gitweb:     http://git.kernel.org/tip/afc2a3523fc6664f3713b594daa1857f37ad87df
Author:     Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
AuthorDate: Tue, 24 Mar 2009 10:50:24 +0100
Committer:  Ingo Molnar <mingo@xxxxxxx>
CommitDate: Tue, 24 Mar 2009 10:56:18 +0100

perf_counter tools: remove glib dependency and fix bugs in kerneltop.c, fix poll()

Paul Mackerras wrote:

> I noticed the poll stuff is bogus - we have a 2D array of struct
> pollfds (MAX_NR_CPUS x MAX_COUNTERS), we fill in a sub-array (with the
> rest being uninitialized, since the array is on the stack) and then
> pass the first nr_cpus elements to poll.  Not what we really meant, I
> suspect. :)  Not even if we only have one counter, since it's the
> counter dimension that varies fastest.

This should fix the most obvious poll fubar.. not enough to fix the
full problem though..

Reported-by: Paul Mackerras <paulus@xxxxxxxxx>
Reported-by: Mike Galbraith <efault@xxxxxx>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Cc: Arjan van de Ven <arjan@xxxxxxxxxxxxxxx>
LKML-Reference: <18888.29986.340328.540512@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxx>


---
 Documentation/perf_counter/kerneltop.c |   11 ++++++-----
 1 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/Documentation/perf_counter/kerneltop.c b/Documentation/perf_counter/kerneltop.c
index ea13e4e..7ebde7a 100644
--- a/Documentation/perf_counter/kerneltop.c
+++ b/Documentation/perf_counter/kerneltop.c
@@ -1157,10 +1157,10 @@ static void mmap_read(struct mmap_data *md)
 
 int main(int argc, char *argv[])
 {
-	struct pollfd event_array[MAX_NR_CPUS][MAX_COUNTERS];
+	struct pollfd event_array[MAX_NR_CPUS * MAX_COUNTERS];
 	struct mmap_data mmap_array[MAX_NR_CPUS][MAX_COUNTERS];
 	struct perf_counter_hw_event hw_event;
-	int i, counter, group_fd;
+	int i, counter, group_fd, nr_poll = 0;
 	unsigned int cpu;
 	int ret;
 
@@ -1214,8 +1214,9 @@ int main(int argc, char *argv[])
 			if (group && group_fd == -1)
 				group_fd = fd[i][counter];
 
-			event_array[i][counter].fd = fd[i][counter];
-			event_array[i][counter].events = POLLIN;
+			event_array[nr_poll].fd = fd[i][counter];
+			event_array[nr_poll].events = POLLIN;
+			nr_poll++;
 
 			mmap_array[i][counter].counter = counter;
 			mmap_array[i][counter].prev = 0;
@@ -1247,7 +1248,7 @@ int main(int argc, char *argv[])
 		}
 
 		if (hits == events)
-			ret = poll(event_array[0], nr_cpus, 1000);
+			ret = poll(event_array, nr_poll, 1000);
 		hits = events;
 	}
 
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