From: "tip-bot2 for Marco Elver" <tip-bot2@linutronix.de>
To: linux-tip-commits@vger.kernel.org
Cc: Peter Zijlstra <peterz@infradead.org>,
Marco Elver <elver@google.com>,
x86@kernel.org, linux-kernel@vger.kernel.org
Subject: [tip: perf/core] perf: Add support for event removal on exec
Date: Fri, 16 Apr 2021 15:01:50 -0000 [thread overview]
Message-ID: <161858531071.29796.4506820814392849055.tip-bot2@tip-bot2> (raw)
In-Reply-To: <20210408103605.1676875-5-elver@google.com>
The following commit has been merged into the perf/core branch of tip:
Commit-ID: 2e498d0a74e5b88a6689ae1b811f247f91ff188e
Gitweb: https://git.kernel.org/tip/2e498d0a74e5b88a6689ae1b811f247f91ff188e
Author: Marco Elver <elver@google.com>
AuthorDate: Thu, 08 Apr 2021 12:35:59 +02:00
Committer: Peter Zijlstra <peterz@infradead.org>
CommitterDate: Fri, 16 Apr 2021 16:32:41 +02:00
perf: Add support for event removal on exec
Adds bit perf_event_attr::remove_on_exec, to support removing an event
from a task on exec.
This option supports the case where an event is supposed to be
process-wide only, and should not propagate beyond exec, to limit
monitoring to the original process image only.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210408103605.1676875-5-elver@google.com
---
include/uapi/linux/perf_event.h | 3 +-
kernel/events/core.c | 70 ++++++++++++++++++++++++++++----
2 files changed, 64 insertions(+), 9 deletions(-)
diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h
index 813efb6..8c5b9f5 100644
--- a/include/uapi/linux/perf_event.h
+++ b/include/uapi/linux/perf_event.h
@@ -390,7 +390,8 @@ struct perf_event_attr {
text_poke : 1, /* include text poke events */
build_id : 1, /* use build id in mmap2 events */
inherit_thread : 1, /* children only inherit if cloned with CLONE_THREAD */
- __reserved_1 : 28;
+ remove_on_exec : 1, /* event is removed from task on exec */
+ __reserved_1 : 27;
union {
__u32 wakeup_events; /* wakeup every n events */
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 3e3c00f..e4a584b 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -4248,6 +4248,57 @@ out:
put_ctx(clone_ctx);
}
+static void perf_remove_from_owner(struct perf_event *event);
+static void perf_event_exit_event(struct perf_event *event,
+ struct perf_event_context *ctx);
+
+/*
+ * Removes all events from the current task that have been marked
+ * remove-on-exec, and feeds their values back to parent events.
+ */
+static void perf_event_remove_on_exec(int ctxn)
+{
+ struct perf_event_context *ctx, *clone_ctx = NULL;
+ struct perf_event *event, *next;
+ LIST_HEAD(free_list);
+ unsigned long flags;
+ bool modified = false;
+
+ ctx = perf_pin_task_context(current, ctxn);
+ if (!ctx)
+ return;
+
+ mutex_lock(&ctx->mutex);
+
+ if (WARN_ON_ONCE(ctx->task != current))
+ goto unlock;
+
+ list_for_each_entry_safe(event, next, &ctx->event_list, event_entry) {
+ if (!event->attr.remove_on_exec)
+ continue;
+
+ if (!is_kernel_event(event))
+ perf_remove_from_owner(event);
+
+ modified = true;
+
+ perf_event_exit_event(event, ctx);
+ }
+
+ raw_spin_lock_irqsave(&ctx->lock, flags);
+ if (modified)
+ clone_ctx = unclone_ctx(ctx);
+ --ctx->pin_count;
+ raw_spin_unlock_irqrestore(&ctx->lock, flags);
+
+unlock:
+ mutex_unlock(&ctx->mutex);
+
+ put_ctx(ctx);
+ if (clone_ctx)
+ put_ctx(clone_ctx);
+}
+
struct perf_read_data {
struct perf_event *event;
bool group;
@@ -7560,18 +7611,18 @@ void perf_event_exec(void)
struct perf_event_context *ctx;
int ctxn;
- rcu_read_lock();
for_each_task_context_nr(ctxn) {
- ctx = current->perf_event_ctxp[ctxn];
- if (!ctx)
- continue;
-
perf_event_enable_on_exec(ctxn);
+ perf_event_remove_on_exec(ctxn);
- perf_iterate_ctx(ctx, perf_event_addr_filters_exec, NULL,
- true);
+ rcu_read_lock();
+ ctx = rcu_dereference(current->perf_event_ctxp[ctxn]);
+ if (ctx) {
+ perf_iterate_ctx(ctx, perf_event_addr_filters_exec,
+ NULL, true);
+ }
+ rcu_read_unlock();
}
- rcu_read_unlock();
}
struct remote_output {
@@ -11656,6 +11707,9 @@ static int perf_copy_attr(struct perf_event_attr __user *uattr,
if (!attr->inherit && attr->inherit_thread)
return -EINVAL;
+ if (attr->remove_on_exec && attr->enable_on_exec)
+ return -EINVAL;
+
out:
return ret;
next prev parent reply other threads:[~2021-04-16 15:02 UTC|newest]
Thread overview: 35+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-04-08 10:35 [PATCH v4 00/10] Add support for synchronous signals on perf events Marco Elver
2021-04-08 10:35 ` [PATCH v4 01/10] perf: Rework perf_event_exit_event() Marco Elver
2021-04-16 15:01 ` [tip: perf/core] " tip-bot2 for Peter Zijlstra
2021-04-08 10:35 ` [PATCH v4 02/10] perf: Apply PERF_EVENT_IOC_MODIFY_ATTRIBUTES to children Marco Elver
2021-04-16 15:01 ` [tip: perf/core] " tip-bot2 for Marco Elver
2021-04-08 10:35 ` [PATCH v4 03/10] perf: Support only inheriting events if cloned with CLONE_THREAD Marco Elver
2021-04-08 10:35 ` [PATCH v4 04/10] perf: Add support for event removal on exec Marco Elver
2021-04-16 15:01 ` tip-bot2 for Marco Elver [this message]
2021-04-08 10:36 ` [PATCH v4 05/10] signal: Introduce TRAP_PERF si_code and si_perf to siginfo Marco Elver
2021-04-16 15:01 ` [tip: perf/core] " tip-bot2 for Marco Elver
[not found] ` <CGME20210420212618eucas1p102b427d1af9c682217dfe093f3eac3e8@eucas1p1.samsung.com>
2021-04-20 21:26 ` [PATCH v4 05/10] " Marek Szyprowski
2021-04-20 22:42 ` Marco Elver
2021-04-21 6:21 ` Marek Szyprowski
2021-04-21 7:35 ` Marek Szyprowski
2021-04-21 8:11 ` Marco Elver
2021-04-21 9:35 ` Marek Szyprowski
2021-04-21 10:57 ` Marek Szyprowski
2021-04-21 11:03 ` Marco Elver
2021-04-21 13:19 ` Marek Szyprowski
2021-04-21 15:11 ` Marco Elver
2021-04-21 16:27 ` Marco Elver
2021-04-21 18:23 ` Marco Elver
2021-04-22 6:12 ` Marek Szyprowski
2021-04-22 6:47 ` Marco Elver
2021-04-22 8:16 ` Jon Hunter
2021-04-26 7:35 ` Alexander Egorenkov
2021-04-21 15:07 ` Jon Hunter
2021-04-08 10:36 ` [PATCH v4 06/10] perf: Add support for SIGTRAP on perf events Marco Elver
2021-04-08 10:36 ` [PATCH v4 07/10] selftests/perf_events: Add kselftest for process-wide sigtrap handling Marco Elver
2021-04-16 15:01 ` [tip: perf/core] " tip-bot2 for Marco Elver
2021-04-08 10:36 ` [PATCH v4 08/10] selftests/perf_events: Add kselftest for remove_on_exec Marco Elver
2021-04-16 15:01 ` [tip: perf/core] " tip-bot2 for Marco Elver
2021-04-08 10:36 ` [PATCH v4 09/10] tools headers uapi: Sync tools/include/uapi/linux/perf_event.h Marco Elver
2021-04-08 10:36 ` [PATCH v4 10/10] perf test: Add basic stress test for sigtrap handling Marco Elver
2021-04-14 8:37 ` [PATCH v4 00/10] Add support for synchronous signals on perf events Peter Zijlstra
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=161858531071.29796.4506820814392849055.tip-bot2@tip-bot2 \
--to=tip-bot2@linutronix.de \
--cc=elver@google.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-tip-commits@vger.kernel.org \
--cc=peterz@infradead.org \
--cc=x86@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).