From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f169.google.com (mail-pl1-f169.google.com [209.85.214.169]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B32D21A238D; Tue, 10 Jun 2025 00:48:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.169 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749516541; cv=none; b=rl87RcWmMyqHFFxwn4DxMGV7Ubxobgq6yiPIujgzMQSj+OcJT6ooBVfYYuXwcEZ+wV1tVVwjfSJgvqYkTUBnUDIqFZ1nq/23rAazMdY6hU7xLY+qX81rOFlDIUXBsJeKo5+s0IeriTH7HHig/ONhY7r44gXRL+3rQB6tGfXfROg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749516541; c=relaxed/simple; bh=lLuZJy5LmIhw6vczV+BjTVeE1qeR4Bfzo8mKouv0f/Q=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=IUrFtKFukWTgHpUlO/hhaiU1CL3UmsuIaRYsvSEFxx/H0oTzfxhkkg00xFjXKK0bgzwl7NRc+a5gpX0RvmZi9JF2/ppgxCUguvUC1mqEHfk8aFd39IgePBLxjPbjfE6tQMBQQqE/HK9t9FxV+Oo1IHA3ppOFD8mGrxyUXpSwMec= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=i9gwK1Qh; arc=none smtp.client-ip=209.85.214.169 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="i9gwK1Qh" Received: by mail-pl1-f169.google.com with SMTP id d9443c01a7336-2349f096605so58078635ad.3; Mon, 09 Jun 2025 17:48:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1749516539; x=1750121339; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=l8SVDvWMO2KmJya58rTe/5tn0uw9qn8OeN6AY1Bam6A=; b=i9gwK1QhKvNoD9Na18lAe55FmYFSMooBkL63aucPTAFfCKJt2kPOXHzYtDEy0xEBlO Dkbr3fxnLZ32vJ5qWg2rLHSdo6JgoAj9jDdUlYbHzr+gNqczdiUtYZ1wdhBNlmLmpf5m klMUDMZlnNg4v/06/ZBWidE50JXIF03wuMlOMCctsMgilx/nbT06RPqwMBsU5i+rDdam pwnjmC5WgwbDYimYdxzKY0+UYTktfL8cGl8mEDJ2hnbtgbtF73orlmnpK2F5ZgzoGVN9 Ey2Z9hbaUNPMQa6JxA0iBLs8/hfYa9K3sorzkilyOxH8C3u0l2hHTzMIbPbIwmtkqb8Z eHTg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1749516539; x=1750121339; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=l8SVDvWMO2KmJya58rTe/5tn0uw9qn8OeN6AY1Bam6A=; b=FbPGBXcHi9ekZBQvxUdJMmG2SXTFLsGHP6BUe2Fc1yjErosHJObluZ7fGXrDUVumMi WWeKZmvual0i+2xyhO8zKyoRUtGpcVN885jGLXhJUWpoJFfMcz5L2vwLpl7sVU89M+g/ s04UjT90bpxvCC6QMz/8gBlgQSJlu8lssMphxZ6pSgO+CKT916X7pQbM7obBovhLONy4 OL97FetwvV1XVGDRlFzZnwEL1NR4rDRVmVoZ5oFdqQb/ipv90DZJSKUbXytjrA/Iv1pW S8FQPLlh2+h0fYRcUNBfFIHUzsgwToqu5URxh3iUcbDu5sUrKrTwjNK1WH1syWAr90hu 267g== X-Forwarded-Encrypted: i=1; AJvYcCUbgwS4nwxbhTAz9cjC6f3i7f5MpQLpM+pDB4F+mcZmTnEGU92Vtp2N/6AgpUfIauM7cCut9ZGOLMnA9UoGw8pBZU0w@vger.kernel.org, AJvYcCWxf9drbTwsFhxDVymP3Mr+S/RfS+sbZ6i1rXsD91m6tf60bDnIdcbMInB4FLpXTlKmc34YHAmvy/jfTg==@vger.kernel.org X-Gm-Message-State: AOJu0Yx8lPQqvzkIcivGyBRlkdW5ThRc2Wf7KpKjkUbDsftPcsJnc6ny /Mp14C7KQqBTVnrcwXnYqepweNfYKWtNkBU2qtI8hC52+dCRdaKW3nC3 X-Gm-Gg: ASbGncv+jO6XPwg4ZehvJO22M9Ydhggu7j6NfNrmUFOJ5jJKx0IJpDrF2VFYf4Ofz5U VNF31+63lqadqOrQDz6FevDKlDhGpanT0RgnynrPTauwf2gHStmiJCvODvbrPaosrTXMQGUYVKY bB5iN1jXmwCBGKNSLPAd5tRXPO++JiLeAmOFJllOz72NPjYnRxmcIj1wLzAkhQm4hbiZ4qMMn3d XYloM38aAx7cvkcUneIxOsG4K5wn07Z6hZl0h/D6HRfyYXHtd0gDtaHtt26xlXkpCnycB0CQlRg 9A79Am/4RUtrKaISjwxFnh4lCIHvHfKPGU+lR+iUYw4w088dzoxJRxSgI4TMPi1bDdguiHWDWKL upFJbAeh+KqwAXjL6gq6UGcMXPE6RS2PM3w== X-Google-Smtp-Source: AGHT+IHbZt8udGE0xv+/8ewbIApjkPoddT1BX0UcOwzQArXV7NE9hqbFiFjNI44py8pBjWJPn7V8Vw== X-Received: by 2002:a17:903:22c7:b0:234:b123:b4ff with SMTP id d9443c01a7336-23601d08686mr202935695ad.21.1749516538976; Mon, 09 Jun 2025 17:48:58 -0700 (PDT) Received: from KERNELXING-MC1.tencent.com ([43.132.141.21]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-236032fcd58sm60713845ad.122.2025.06.09.17.48.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 09 Jun 2025 17:48:58 -0700 (PDT) From: Jason Xing To: axboe@kernel.dk, rostedt@goodmis.org, mhiramat@kernel.org, mathieu.desnoyers@efficios.com, akpm@linux-foundation.org Cc: linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, linux-trace-kernel@vger.kernel.org, Jason Xing , Yushan Zhou Subject: [PATCH v4 3/5] relayfs: introduce getting relayfs statistics function Date: Tue, 10 Jun 2025 08:48:42 +0800 Message-Id: <20250610004844.66688-4-kerneljasonxing@gmail.com> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20250610004844.66688-1-kerneljasonxing@gmail.com> References: <20250610004844.66688-1-kerneljasonxing@gmail.com> Precedence: bulk X-Mailing-List: linux-block@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Jason Xing In this version, only support getting the counter for buffer full and implement the framework of how it works. Users can pass certain flag to fetch what field/statistics they expect to know. Each time it only returns one result. So do not pass multiple flags. Reviewed-by: Yushan Zhou Reviewed-by: Masami Hiramatsu (Google) Signed-off-by: Jason Xing --- include/linux/relay.h | 7 +++++++ kernel/relay.c | 30 ++++++++++++++++++++++++++++++ 2 files changed, 37 insertions(+) diff --git a/include/linux/relay.h b/include/linux/relay.h index cd77eb285a48..5310967f9d74 100644 --- a/include/linux/relay.h +++ b/include/linux/relay.h @@ -31,6 +31,12 @@ /* * Relay buffer statistics */ +enum { + RELAY_STATS_BUF_FULL = (1 << 0), + + RELAY_STATS_LAST = RELAY_STATS_BUF_FULL, +}; + struct rchan_buf_stats { unsigned int full_count; /* counter for buffer full */ @@ -167,6 +173,7 @@ struct rchan *relay_open(const char *base_filename, void *private_data); extern void relay_close(struct rchan *chan); extern void relay_flush(struct rchan *chan); +size_t relay_stats(struct rchan *chan, int flags); extern void relay_subbufs_consumed(struct rchan *chan, unsigned int cpu, size_t consumed); diff --git a/kernel/relay.c b/kernel/relay.c index eb3f630f3896..fd70d0e03216 100644 --- a/kernel/relay.c +++ b/kernel/relay.c @@ -701,6 +701,36 @@ void relay_flush(struct rchan *chan) } EXPORT_SYMBOL_GPL(relay_flush); +/** + * relay_stats - get channel buffer statistics + * @chan: the channel + * @flags: select particular information to get + * + * Returns the count of certain field that caller specifies. + */ +size_t relay_stats(struct rchan *chan, int flags) +{ + unsigned int i, count = 0; + struct rchan_buf *rbuf; + + if (!chan || flags > RELAY_STATS_LAST) + return 0; + + if (chan->is_global) { + rbuf = *per_cpu_ptr(chan->buf, 0); + if (flags & RELAY_STATS_BUF_FULL) + count = rbuf->stats.full_count; + } else { + for_each_online_cpu(i) { + rbuf = *per_cpu_ptr(chan->buf, i); + if (rbuf && flags & RELAY_STATS_BUF_FULL) + count += rbuf->stats.full_count; + } + } + + return count; +} + /** * relay_file_open - open file op for relay files * @inode: the inode -- 2.43.5