From nobody Thu Apr 2 17:16:38 2026 Received: from mail-ed1-f74.google.com (mail-ed1-f74.google.com [209.85.208.74]) (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 D988B3E9595 for ; Mon, 9 Mar 2026 16:26:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.208.74 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773073571; cv=none; b=oyXH6QB47ZqGpGf2AmC7HsXanI8UpWoepk63AHpKc39qDZRcnjgYpRYS8jIx0TPNUCxJ2bk6VdkHXC0e3pl2LWF9lA0hVeOiBFmj2zsNefmz3vk6n3e17gLPNPmmhKd1s8yPsWXWnYKHxrLClgs8edP+LS9qkDqnM5CagGVa9zQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773073571; c=relaxed/simple; bh=nCoqfYLkFALSGqFmK5+OUBL2T+SjXlSRskeq0sqM6lo=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=BzpsUK5sLT3S4R3U4nIlUstndKDEPQwz1zi+O+t1RSr4pMkmnxNhLJt2HRRiASooir+RjBWP2YPSV2QPrdkIeVWDO/D6VeHTsV0uUYsD+hlQggbc+H9bzpXrarrP6hNB/mAHCJiPjkPOIpJ7lfcTMzPZBLsinFLYVjXR0UMaOf4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--vdonnefort.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=B/d3hPqq; arc=none smtp.client-ip=209.85.208.74 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--vdonnefort.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="B/d3hPqq" Received: by mail-ed1-f74.google.com with SMTP id 4fb4d7f45d1cf-6618bc12875so4253808a12.2 for ; Mon, 09 Mar 2026 09:26:09 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1773073568; x=1773678368; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=/el005jPydhTNUS1hr5dgVCq32s5flSC0Li9+BCYSpc=; b=B/d3hPqqesDTDde344RwpKWuzM3jOIJIXMK3NE7mtahN9wc5acI/BnQrnnmZBuASsP /i0lVpgqF37ha0u/rESqVByAixDzHwuWLfLWz2h5h8fUsOLKdL0iNF5ZUPuzX+QjaVPZ Tuiz/w8v5zHFeoAdbqrJ4UX1eW2om8pNeRoJQaiyjMzkDOdb68w7z17zUkJGPlcCRPi2 3k46hUX/eoG3rra9sf+8hOVIsREKGzsBTYh533OgglOij+P8fUIh75HxOFeSdad07rL1 Rk2hgr/VJDDRYctGFfzVk+9tbF58DjzrNC93PFQvGPkRh6Eje+JHa4X7+gDy0kXRy7Ck ypHg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1773073568; x=1773678368; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=/el005jPydhTNUS1hr5dgVCq32s5flSC0Li9+BCYSpc=; b=FVRibcT0OH3wtc3gbMcu/btLgEkg7shhPVkD78rZ11AqZvopZyB8TgzdPSaUli3cS1 Y+ZPZVwfvr7+jfH52zC5MYvm9y1Xb+nQRLrJmwbELisDiAivi1amGT+maRHpMS83rdo7 0TYiGJcJ4RPe/Put2g9zNhQyfL6mA/FQxIWa/Ku7E0WSLAL1RUpvueF4vTWwi+KMMiGf M4j9Po/C2Axhg6cXK3Hg6cye/bgVzYfs2rDj7XXdbWJsIZ86OE3S/7Ix9915Rgk7HOsj BkiLM2OxvnhvMyCVnvrPuee5XgoxgmvlFlFIn7yO4f7yHXlt7LGkjOZu7Cwfmrz7LT/G wQ+g== X-Forwarded-Encrypted: i=1; AJvYcCUX0xOlW5d9QL8flndH1myLrZF/+6ydPHBJ23YL2OMrqmzpcyRL5zd7KHxpndc3Z3LeuCbtn24J7wTrPjo=@vger.kernel.org X-Gm-Message-State: AOJu0Yy7H1uGvZD4l6MA53ms9+KeEnTCHjblHcPtYLm1EPuK4gfVSes5 FRS5DQkovCEmHKNnCArKxhsz3QjwXMf4PjnzV+G+DolWMOxl9Wl0bR04vssLjaUcyfo1dIrGFXF 4A9wQXSCndqFJUUpwCsVjKg== X-Received: from ejzd4.prod.google.com ([2002:a17:906:c204:b0:b93:57d1:f5fe]) (user=vdonnefort job=prod-delivery.src-stubby-dispatcher) by 2002:a17:907:c13:b0:b96:ef71:49f1 with SMTP id a640c23a62f3a-b96ef715938mr293231166b.15.1773073568096; Mon, 09 Mar 2026 09:26:08 -0700 (PDT) Date: Mon, 9 Mar 2026 16:24:54 +0000 In-Reply-To: <20260309162516.2623589-1-vdonnefort@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260309162516.2623589-1-vdonnefort@google.com> X-Mailer: git-send-email 2.53.0.473.g4a7958ca14-goog Message-ID: <20260309162516.2623589-9-vdonnefort@google.com> Subject: [PATCH v14 08/30] tracing: Add init callback to trace remotes From: Vincent Donnefort To: rostedt@goodmis.org, mhiramat@kernel.org, mathieu.desnoyers@efficios.com, linux-trace-kernel@vger.kernel.org, maz@kernel.org, oliver.upton@linux.dev, joey.gouly@arm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com Cc: kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, jstultz@google.com, qperret@google.com, will@kernel.org, aneesh.kumar@kernel.org, kernel-team@android.com, linux-kernel@vger.kernel.org, Vincent Donnefort Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Add a .init call back so the trace remote callers can add entries to the tracefs directory. Reviewed-by: Steven Rostedt (Google) Signed-off-by: Vincent Donnefort diff --git a/include/linux/trace_remote.h b/include/linux/trace_remote.h index 10ca03dc192b..090c58b7d92b 100644 --- a/include/linux/trace_remote.h +++ b/include/linux/trace_remote.h @@ -3,10 +3,13 @@ #ifndef _LINUX_TRACE_REMOTE_H #define _LINUX_TRACE_REMOTE_H =20 +#include #include =20 /** * struct trace_remote_callbacks - Callbacks used by Tracefs to control th= e remote + * @init: Called once the remote has been registered. Allows the + * caller to extend the Tracefs remote directory * @load_trace_buffer: Called before Tracefs accesses the trace buffer fo= r the first * time. Must return a &trace_buffer_desc * (most likely filled with trace_remote_alloc_buffer()) @@ -22,6 +25,7 @@ * new reader-page from the @cpu ring-buffer. */ struct trace_remote_callbacks { + int (*init)(struct dentry *d, void *priv); struct trace_buffer_desc *(*load_trace_buffer)(unsigned long size, void *= priv); void (*unload_trace_buffer)(struct trace_buffer_desc *desc, void *priv); int (*enable_tracing)(bool enable, void *priv); diff --git a/kernel/trace/trace_remote.c b/kernel/trace/trace_remote.c index 039ba71c3b3e..294d051dcef1 100644 --- a/kernel/trace/trace_remote.c +++ b/kernel/trace/trace_remote.c @@ -863,6 +863,7 @@ static int trace_remote_init_tracefs(const char *name, = struct trace_remote *remo int trace_remote_register(const char *name, struct trace_remote_callbacks = *cbs, void *priv) { struct trace_remote *remote; + int ret; =20 remote =3D kzalloc_obj(*remote); if (!remote) @@ -880,7 +881,11 @@ int trace_remote_register(const char *name, struct tra= ce_remote_callbacks *cbs, return -ENOMEM; } =20 - return 0; + ret =3D cbs->init ? cbs->init(remote->dentry, priv) : 0; + if (ret) + pr_err("Init failed for trace remote '%s' (%d)\n", name, ret); + + return ret; } EXPORT_SYMBOL_GPL(trace_remote_register); =20 --=20 2.53.0.473.g4a7958ca14-goog