From 6dd273f44669de98bfff16371c09065671cbbad6 Mon Sep 17 00:00:00 2001 From: Andrew Murray Date: Thu, 10 Jan 2019 13:53:26 +0000 Subject: [PATCH] perf/core, arch/alpha: Strengthen exclusion checks with PERF_PMU_CAP_NO_EXCLUDE As the Alpha PMU doesn't support context exclusion let's advertise the PERF_PMU_CAP_NO_EXCLUDE capability. This ensures that perf will prevent us from handling events where any exclusion flags are set. Let's also remove the now unnecessary check for exclusion flags. This change means that __hw_perf_event_init will now also indicate that it doesn't support exclude_host and exclude_guest and will now implicitly return -EINVAL instead of -EPERM. This is likely more desirable as -EPERM will result in a kernel.perf_event_paranoid related warning from the perf userspace utility. Signed-off-by: Andrew Murray Signed-off-by: Peter Zijlstra (Intel) Cc: Arnaldo Carvalho de Melo Cc: Benjamin Herrenschmidt Cc: Borislav Petkov Cc: Ivan Kokshaysky Cc: Linus Torvalds Cc: Mark Rutland Cc: Matt Turner Cc: Michael Ellerman Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Richard Henderson Cc: Russell King Cc: Sascha Hauer Cc: Shawn Guo Cc: Thomas Gleixner Cc: Will Deacon Cc: linux-arm-kernel@lists.infradead.org Cc: linuxppc-dev@lists.ozlabs.org Cc: robin.murphy@arm.com Cc: suzuki.poulose@arm.com Link: https://lkml.kernel.org/r/1547128414-50693-5-git-send-email-andrew.murray@arm.com Signed-off-by: Ingo Molnar --- arch/alpha/kernel/perf_event.c | 7 +------ 1 file changed, 1 insertion(+), 6 deletions(-) diff --git a/arch/alpha/kernel/perf_event.c b/arch/alpha/kernel/perf_event.c index 5613aa378a83..4341ccf5c0c4 100644 --- a/arch/alpha/kernel/perf_event.c +++ b/arch/alpha/kernel/perf_event.c @@ -630,12 +630,6 @@ static int __hw_perf_event_init(struct perf_event *event) return ev; } - /* The EV67 does not support mode exclusion */ - if (attr->exclude_kernel || attr->exclude_user - || attr->exclude_hv || attr->exclude_idle) { - return -EPERM; - } - /* * We place the event type in event_base here and leave calculation * of the codes to programme the PMU for alpha_pmu_enable() because @@ -771,6 +765,7 @@ static struct pmu pmu = { .start = alpha_pmu_start, .stop = alpha_pmu_stop, .read = alpha_pmu_read, + .capabilities = PERF_PMU_CAP_NO_EXCLUDE, };