From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 15A9F2264DC; Thu, 30 Oct 2025 03:27:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761794834; cv=none; b=JXeqPZ73rPGRC1Ldh+CXQD95PoIJi03B1T3hppXbk+/paec00LzcYZ8DAbkpOfkXbBtW9kE7kmn6s1SPBkeHLBZF1m4fB7HdyKf3ajufnP1PE7Fko/gtbv1jPrSuKwunfmYIMFbibzoD4GbaoyBuR0HfKzERVpOKJuFKRlRt8YI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761794834; c=relaxed/simple; bh=cfhICDAycpdcZ0C2xlkyCdUlNHCGdRQjBFptHTiR07c=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=SGE7PQVirZfKXz8/LRtR22JGKq0vq0w1hRWKFPk0vkd3ITYhcNqVR3c6ViiRjQlvInQKc43TqsFmDSDMA7KdsGiW+48I66U9LoPLSMjj9ZqGw/pbutPexyhRwP9oNdrFTG/AlBHLlz4JCk9sng9FMHEGMWFGn++nmhcuKlGj9+0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=q3leZ3EQ; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="q3leZ3EQ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B6686C4CEFF; Thu, 30 Oct 2025 03:27:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1761794833; bh=cfhICDAycpdcZ0C2xlkyCdUlNHCGdRQjBFptHTiR07c=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=q3leZ3EQv52ijoBcpC1BDyWPH5QcmZcnGd0YsDnPcBk8E4QDQXA1B4Iny+PMY0mNF evV8c9vtjwD693qQKwKaiueOvg2jyFVsgl53UpUzbdv8fFHjdXrQUQ2dsFm4ohwRfs AQUa/IPdbPamjlgf2YNgY0LZ5mWDnQ9n/UuuV3XEyPcbqt/DPrdJwmHHbz77nHJctX YBH0qaEA9otp/en9y/CiPWivt6DjAJh+MNhI9Xu9+fOjpeslkEh8PyvjE7WnMjHrVe eRTvWTFNvkQ/rMxLnksAkgvoFu53//RxqInaxN/RM2V/lQpn5Vp43T8n/CCmy3zRsX vMuVJZ5sIBsTw== From: "Masami Hiramatsu (Google)" To: Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Namhyung Kim , Steven Rostedt Cc: Mark Rutland , Alexander Shishkin , Jiri Olsa , Ian Rogers , Adrian Hunter , Masami Hiramatsu , Mathieu Desnoyers , linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, Will Deacon , Catalin Marinas , linux-arm-kernel@lists.infradead.org Subject: [PATCH 1/2] perf: Introduce default_overflow_compatible flag Date: Thu, 30 Oct 2025 12:27:07 +0900 Message-ID: <176179482721.959775.9568162681903659824.stgit@devnote2> X-Mailer: git-send-email 2.43.0 In-Reply-To: <176179481538.959775.12326313742393696258.stgit@devnote2> References: <176179481538.959775.12326313742393696258.stgit@devnote2> User-Agent: StGit/0.19 Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit From: Masami Hiramatsu (Google) Instead of checking whether event->overflow_handler everytime in is_default_overflow_handler(), just use a flag to check it once when registering the handler. Signed-off-by: Masami Hiramatsu (Google) --- include/linux/perf_event.h | 9 ++------- kernel/events/core.c | 2 ++ 2 files changed, 4 insertions(+), 7 deletions(-) diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h index fd1d91017b99..40dd897e26b0 100644 --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -902,6 +902,7 @@ struct perf_event { u64 (*clock)(void); perf_overflow_handler_t overflow_handler; void *overflow_handler_context; + bool default_overflow_compatible; struct bpf_prog *prog; u64 bpf_cookie; @@ -1505,13 +1506,7 @@ extern int perf_event_output(struct perf_event *event, static inline bool is_default_overflow_handler(struct perf_event *event) { - perf_overflow_handler_t overflow_handler = event->overflow_handler; - - if (likely(overflow_handler == perf_event_output_forward)) - return true; - if (unlikely(overflow_handler == perf_event_output_backward)) - return true; - return false; + return event->default_overflow_compatible; } extern void diff --git a/kernel/events/core.c b/kernel/events/core.c index 177e57c1a362..6bbbde82cb21 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -12946,9 +12946,11 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu, } else if (is_write_backward(event)){ event->overflow_handler = perf_event_output_backward; event->overflow_handler_context = NULL; + event->default_overflow_compatible = true; } else { event->overflow_handler = perf_event_output_forward; event->overflow_handler_context = NULL; + event->default_overflow_compatible = true; } perf_event__state_init(event);