From patchwork Sat Oct 26 15:46:28 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mathieu Desnoyers X-Patchwork-Id: 13852268 Received: from smtpout.efficios.com (smtpout.efficios.com [167.114.26.122]) (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 ECC8C7EEFD; Sat, 26 Oct 2024 15:48:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=167.114.26.122 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729957697; cv=none; b=g50HEFcGb2/KKSrM5wp2otFkwEa/mpDwXY1lqO33l2kbRuzks8fOkPzRk5jfZ63F+BRi5Zoqoz+KA6+xkwns+GRGIL3ofNhJvhq0Egg8mC7K5GjBlJaqXGzZZ5Q3zG1+/GdkwoNi/4UjUZ7nPWm9HlDLtfc2+mIJ+D7cVi/KiXM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729957697; c=relaxed/simple; bh=Yt3JqGyHnlN/PMXwaeZS2HWMIxiUalPTFf0y/3FdW84=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=ZNHut40AyaahukWP82601PrcFvE9r8R78Qult7IYB/hNfEwgFzlWmclYQY9MJzzCsmlmWl/wj2NPF869iFZmIpsmPhsDo785aiZRxfOFQH4FzEmhZDfcGJK6c7ezztTGNFKcZQINT5sWwUssrtTHZStER0tU5VzMRtrLZ7AhNIQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=efficios.com; spf=pass smtp.mailfrom=efficios.com; dkim=pass (2048-bit key) header.d=efficios.com header.i=@efficios.com header.b=FFZVl9wN; arc=none smtp.client-ip=167.114.26.122 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=efficios.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=efficios.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=efficios.com header.i=@efficios.com header.b="FFZVl9wN" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=efficios.com; s=smtpout1; t=1729957694; bh=Yt3JqGyHnlN/PMXwaeZS2HWMIxiUalPTFf0y/3FdW84=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=FFZVl9wN5VzrK90vBTebnKJw5b3b/ESDnfk20WGExNH2v41mnlXXXmLCnBZkG7cv9 kmXuB4jQcni/zWcHiegRcLe/niCAds0jRt4xHDzEWl00IO4jVdj05YszBcBex/MIfe w95WP6J4S4YwU7HMl/Ke848MB+wm5OKApGxlGDq9kq3BRRkth8ceshQRGyGkFn69oG P23PrflB04Lv9SHP+Kjbx1n+v6pjAqeeEPy15ytfo4LKFcM6Tdg2oAaOdL/KTuT81R pmAXUsW1uIXzHIHY7x9Wl8td7vHuB3FxtwWVWqKvb5EMhXbxC7VsGTooMhpIdMq2Je 4cnbZlrvhOyaQ== Received: from thinkos.internal.efficios.com (unknown [IPv6:2606:6d00:100:4000:cacb:9855:de1f:ded2]) by smtpout.efficios.com (Postfix) with ESMTPSA id 4XbPF96SvszNmN; Sat, 26 Oct 2024 11:48:13 -0400 (EDT) From: Mathieu Desnoyers To: Steven Rostedt Cc: linux-kernel@vger.kernel.org, Mathieu Desnoyers , Michael Jeanson , Masami Hiramatsu , Peter Zijlstra , Alexei Starovoitov , Yonghong Song , "Paul E . McKenney" , Ingo Molnar , Arnaldo Carvalho de Melo , Mark Rutland , Alexander Shishkin , Namhyung Kim , Andrii Nakryiko , bpf@vger.kernel.org, Joel Fernandes , Jordan Rife Subject: [RFC PATCH v3 2/3] tracing: Introduce tracepoint_is_syscall() Date: Sat, 26 Oct 2024 11:46:28 -0400 Message-Id: <20241026154629.593041-2-mathieu.desnoyers@efficios.com> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20241026154629.593041-1-mathieu.desnoyers@efficios.com> References: <20241026154629.593041-1-mathieu.desnoyers@efficios.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-State: RFC Introduce a "syscall" flag within the extended structure to know whether a tracepoint needs rcu tasks trace grace period before reclaim. This can be queried using tracepoint_is_syscall(). Signed-off-by: Mathieu Desnoyers Cc: Michael Jeanson Cc: Steven Rostedt Cc: Masami Hiramatsu Cc: Peter Zijlstra Cc: Alexei Starovoitov Cc: Yonghong Song Cc: Paul E. McKenney Cc: Ingo Molnar Cc: Arnaldo Carvalho de Melo Cc: Mark Rutland Cc: Alexander Shishkin Cc: Namhyung Kim Cc: Andrii Nakryiko Cc: bpf@vger.kernel.org Cc: Joel Fernandes Cc: Jordan Rife --- include/linux/tracepoint-defs.h | 2 ++ include/linux/tracepoint.h | 24 ++++++++++++++++++++++++ include/trace/define_trace.h | 2 +- 3 files changed, 27 insertions(+), 1 deletion(-) diff --git a/include/linux/tracepoint-defs.h b/include/linux/tracepoint-defs.h index 967c08d9da84..53119e074c87 100644 --- a/include/linux/tracepoint-defs.h +++ b/include/linux/tracepoint-defs.h @@ -32,6 +32,8 @@ struct tracepoint_func { struct tracepoint_ext { int (*regfunc)(void); void (*unregfunc)(void); + /* Flags. */ + unsigned int syscall:1; }; struct tracepoint { diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h index 83dc24ee8b13..93e70bc64533 100644 --- a/include/linux/tracepoint.h +++ b/include/linux/tracepoint.h @@ -104,6 +104,12 @@ void for_each_tracepoint_in_module(struct module *mod, * tracepoint_synchronize_unregister must be called between the last tracepoint * probe unregistration and the end of module exit to make sure there is no * caller executing a probe when it is freed. + * + * An alternative is to use the following for batch reclaim associated + * with a given tracepoint: + * + * - tracepoint_is_syscall() == false: call_rcu() + * - tracepoint_is_syscall() == true: call_rcu_tasks_trace() */ #ifdef CONFIG_TRACEPOINTS static inline void tracepoint_synchronize_unregister(void) @@ -111,9 +117,17 @@ static inline void tracepoint_synchronize_unregister(void) synchronize_rcu_tasks_trace(); synchronize_rcu(); } +static inline bool tracepoint_is_syscall(struct tracepoint *tp) +{ + return tp->ext && tp->ext->syscall; +} #else static inline void tracepoint_synchronize_unregister(void) { } +static inline bool tracepoint_is_syscall(struct tracepoint *tp) +{ + return false; +} #endif #ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS @@ -345,6 +359,15 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p) struct tracepoint_ext __tracepoint_ext_##_name = { \ .regfunc = _reg, \ .unregfunc = _unreg, \ + .syscall = false, \ + }; \ + __DEFINE_TRACE_EXT(_name, &__tracepoint_ext_##_name, PARAMS(_proto), PARAMS(_args)); + +#define DEFINE_TRACE_SYSCALL(_name, _reg, _unreg, _proto, _args) \ + struct tracepoint_ext __tracepoint_ext_##_name = { \ + .regfunc = _reg, \ + .unregfunc = _unreg, \ + .syscall = true, \ }; \ __DEFINE_TRACE_EXT(_name, &__tracepoint_ext_##_name, PARAMS(_proto), PARAMS(_args)); @@ -389,6 +412,7 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p) #define __DECLARE_TRACE_SYSCALL __DECLARE_TRACE #define DEFINE_TRACE_FN(name, reg, unreg, proto, args) +#define DEFINE_TRACE_SYSCALL(name, reg, unreg, proto, args) #define DEFINE_TRACE(name, proto, args) #define EXPORT_TRACEPOINT_SYMBOL_GPL(name) #define EXPORT_TRACEPOINT_SYMBOL(name) diff --git a/include/trace/define_trace.h b/include/trace/define_trace.h index ff5fa17a6259..63fea2218afa 100644 --- a/include/trace/define_trace.h +++ b/include/trace/define_trace.h @@ -48,7 +48,7 @@ #undef TRACE_EVENT_SYSCALL #define TRACE_EVENT_SYSCALL(name, proto, args, struct, assign, print, reg, unreg) \ - DEFINE_TRACE_FN(name, reg, unreg, PARAMS(proto), PARAMS(args)) + DEFINE_TRACE_SYSCALL(name, reg, unreg, PARAMS(proto), PARAMS(args)) #undef TRACE_EVENT_NOP #define TRACE_EVENT_NOP(name, proto, args, struct, assign, print)