linux-kernel - [PATCH] ARC: perf: ARC 700 PMU doesn't support sampling events

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:	Wed, 13 Nov 2013 16:06:06 +0100
From:	Mischa Jonker <Mischa.Jonker@...opsys.com>
To:	linux-kernel@...r.kernel.org
Cc:	Mischa Jonker <Mischa.Jonker@...opsys.com>,
	Peter Zijlstra <a.p.zijlstra@...llo.nl>,
	Vineet Gupta <Vineet.Gupta1@...opsys.com>
Subject: [PATCH] ARC: perf: ARC 700 PMU doesn't support sampling events

The ARC 700 does not have an interrupt associated with it, and as
such it cannot trigger when a counter overflows. As the counters are
48 bit, it will usually take at least 100 days before a counter
overflows, so for mere counting of events, there is no problem.
Sampling is not supported though.

Cc: Peter Zijlstra <a.p.zijlstra@...llo.nl>
Cc: Vineet Gupta <vgupta@...opsys.com>
Signed-off-by: Mischa Jonker <mjonker@...opsys.com>
---
 arch/arc/kernel/perf_event.c |    4 ++++
 1 file changed, 4 insertions(+)

diff --git a/arch/arc/kernel/perf_event.c b/arch/arc/kernel/perf_event.c
index 759e5f3..e46d81f 100644
--- a/arch/arc/kernel/perf_event.c
+++ b/arch/arc/kernel/perf_event.c
@@ -99,6 +99,10 @@ static int arc_pmu_event_init(struct perf_event *event)
 	struct hw_perf_event *hwc = &event->hw;
 	int ret;
 
+	/* ARC 700 PMU does not support sampling events */
+	if (is_sampling_event(event))
+		return -ENOENT;
+
 	switch (event->attr.type) {
 	case PERF_TYPE_HARDWARE:
 		if (event->attr.config >= PERF_COUNT_HW_MAX)
-- 
1.7.9.5

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/