From: Rob Herring <robh@kernel.org>
To: Will Deacon <will@kernel.org>,
Catalin Marinas <catalin.marinas@arm.com>,
Peter Zijlstra <peterz@infradead.org>,
Ingo Molnar <mingo@redhat.com>,
Mark Rutland <mark.rutland@arm.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>,
Jiri Olsa <jolsa@redhat.com>,
Kan Liang <kan.liang@linux.intel.com>,
Ian Rogers <irogers@google.com>,
Alexander Shishkin <alexander.shishkin@linux.intel.com>,
honnappa.nagarahalli@arm.com, Zachary.Leaf@arm.com,
Raphael Gault <raphael.gault@arm.com>,
Jonathan Cameron <Jonathan.Cameron@huawei.com>,
Namhyung Kim <namhyung@kernel.org>,
Itaru Kitayama <itaru.kitayama@gmail.com>,
linux-arm-kernel@lists.infradead.org,
linux-kernel@vger.kernel.org
Subject: [PATCH v8 1/5] perf: Add a counter for number of user access events in context
Date: Mon, 17 May 2021 14:54:01 -0500 [thread overview]
Message-ID: <20210517195405.3079458-2-robh@kernel.org> (raw)
In-Reply-To: <20210517195405.3079458-1-robh@kernel.org>
When scheduling a task's context, we need to know if the task has any
user accessible events in order to enable or disable user access.
Walking the context's list of events would be slow, so add a counter
to track this.
Signed-off-by: Rob Herring <robh@kernel.org>
---
include/linux/perf_event.h | 1 +
1 file changed, 1 insertion(+)
diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index f5a6a2f069ed..4cf081e22b76 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -822,6 +822,7 @@ struct perf_event_context {
int nr_stat;
int nr_freq;
int rotate_disable;
+ atomic_t nr_user;
/*
* Set when nr_events != nr_active, except tolerant to events not
* necessary to be active due to scheduling constraints, such as cgroups.
--
2.27.0
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2021-05-17 19:56 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-05-17 19:54 [PATCH v8 0/5] arm64 userspace counter support Rob Herring
2021-05-17 19:54 ` Rob Herring [this message]
2021-05-17 19:54 ` [PATCH v8 2/5] perf: Track per-PMU sched_task() callback users Rob Herring
2021-05-17 19:54 ` [PATCH v8 3/5] arm64: perf: Enable PMU counter userspace access for perf event Rob Herring
2021-06-01 13:55 ` Mark Rutland
2021-06-01 15:00 ` Rob Herring
2021-06-01 17:11 ` Mark Rutland
2021-06-03 16:40 ` Rob Herring
2021-07-21 15:59 ` Rob Herring
2021-05-17 19:54 ` [PATCH v8 4/5] arm64: perf: Add userspace counter access disable switch Rob Herring
2021-06-01 12:57 ` Will Deacon
2021-05-17 19:54 ` [PATCH v8 5/5] Documentation: arm64: Document PMU counters access from userspace Rob Herring
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20210517195405.3079458-2-robh@kernel.org \
--to=robh@kernel.org \
--cc=Jonathan.Cameron@huawei.com \
--cc=Zachary.Leaf@arm.com \
--cc=acme@kernel.org \
--cc=alexander.shishkin@linux.intel.com \
--cc=catalin.marinas@arm.com \
--cc=honnappa.nagarahalli@arm.com \
--cc=irogers@google.com \
--cc=itaru.kitayama@gmail.com \
--cc=jolsa@redhat.com \
--cc=kan.liang@linux.intel.com \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mark.rutland@arm.com \
--cc=mingo@redhat.com \
--cc=namhyung@kernel.org \
--cc=peterz@infradead.org \
--cc=raphael.gault@arm.com \
--cc=will@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).