From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 81EC8C433EF for ; Tue, 19 Oct 2021 16:56:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5DF5B6113D for ; Tue, 19 Oct 2021 16:56:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233858AbhJSQ6t (ORCPT ); Tue, 19 Oct 2021 12:58:49 -0400 Received: from mail.kernel.org ([198.145.29.99]:40798 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229774AbhJSQ6s (ORCPT ); Tue, 19 Oct 2021 12:58:48 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 759766113B; Tue, 19 Oct 2021 16:56:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1634662595; bh=O/2mCEk859jM6shQhgv+fX2GqL6oT0eP64zQhWzS8XA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=vQOwAFXnmBJNnyD0+d8jW5THLSLuYsgiKsPzu07BEx1yVJnYmmNHNqlRrMZIwgu1C xExURgAQOYBOzdSRNhaD0IHOPr7ivqJhBCryPsc4amDTsXAWERIPfl01w61UZ07AJa /Ag9TRIuzBWVtxYgaor2LcbKOhURKp09PhhVeDhTQNhJhRtuKSAXUWkTRJ7pa/7WFX JAP8yPACcKApT+4+M8nFjYR9e8iNfuKi0sFE97Nv1SEc6DGGg1SDWz6hxr7CgRmdKD yAah+9IgFTuH9Eg8CSia0MEKsc+Ef22BTNwwyJxjaCHvE5sO6m+JvBO9ajfG2K+g/d EDLoohP9itwag== Received: by quaco.ghostprotocols.net (Postfix, from userid 1000) id E68B8410A1; Tue, 19 Oct 2021 13:56:32 -0300 (-03) Date: Tue, 19 Oct 2021 13:56:32 -0300 From: Arnaldo Carvalho de Melo To: Alistair Francis Cc: linux-riscv@lists.infradead.org, linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org, alistair23@gmail.com, namhyung@kernel.org, jolsa@redhat.com, alexander.shishkin@linux.intel.com, mark.rutland@arm.com, dave@stgolabs.net, dvhart@infradead.org, peterz@infradead.org, mingo@redhat.com, tglx@linutronix.de, atish.patra@wdc.com, arnd@arndb.de, Alistair Francis Subject: Re: [PATCH v2 1/2] perf bench futex: Use a 64-bit time_t Message-ID: References: <20211015005634.2658470-1-alistair.francis@opensource.wdc.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20211015005634.2658470-1-alistair.francis@opensource.wdc.com> X-Url: http://acmel.wordpress.com Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Em Fri, Oct 15, 2021 at 10:56:33AM +1000, Alistair Francis escreveu: > From: Alistair Francis > > Convert tools/perf to only use a 64-bit time_t. On 64-bit architectures > this isn't a functional change. On 32-bit architectures we now only > perform 64-bit time_t syscalls (__NR_futex_time64) and use a struct > timespec64. > > This won't work on kernels before 5.1, but as perf is tied to the kernel > that's ok. No, perf is not tied to the kernel, one can use a new perf tool on any previous kernel, and an old perf tool should work on new kernels as well. - Arnaldo > This allows us to build perf for 32-bit architectures with 64-bit time_t > like RISC-V 32-bit. > > Signed-off-by: Alistair Francis > --- > tools/perf/bench/futex.h | 26 ++++++++++++++++++++------ > 1 file changed, 20 insertions(+), 6 deletions(-) > > diff --git a/tools/perf/bench/futex.h b/tools/perf/bench/futex.h > index b3853aac3021c..b9665d43d2988 100644 > --- a/tools/perf/bench/futex.h > +++ b/tools/perf/bench/futex.h > @@ -12,6 +12,7 @@ > #include > #include > #include > +#include > > struct bench_futex_parameters { > bool silent; > @@ -27,12 +28,14 @@ struct bench_futex_parameters { > unsigned int nrequeue; > }; > > +#define timespec64 __kernel_timespec > + > /** > * futex() - SYS_futex syscall wrapper > * @uaddr: address of first futex > * @op: futex op code > * @val: typically expected value of uaddr, but varies by op > - * @timeout: typically an absolute struct timespec (except where noted > + * @timeout: typically an absolute struct timespec64 (except where noted > * otherwise). Overloaded by some ops > * @uaddr2: address of second futex for some ops > * @val3: varies by op > @@ -47,15 +50,26 @@ struct bench_futex_parameters { > * These argument descriptions are the defaults for all > * like-named arguments in the following wrappers except where noted below. > */ > -#define futex(uaddr, op, val, timeout, uaddr2, val3, opflags) \ > - syscall(SYS_futex, uaddr, op | opflags, val, timeout, uaddr2, val3) > +/** > + * We only support 64-bit time_t for the timeout. > + * On 64-bit architectures we can use __NR_futex > + * On 32-bit architectures we use __NR_futex_time64. This only works on kernel > + * versions 5.1+. > + */ > +#if __BITS_PER_LONG == 64 > +# define futex(uaddr, op, val, timeout, uaddr2, val3, opflags) \ > + syscall(__NR_futex, uaddr, op | opflags, val, timeout, uaddr2, val3) > +#else > +# define futex(uaddr, op, val, timeout, uaddr2, val3, opflags) \ > + syscall(__NR_futex_time64, uaddr, op | opflags, val, timeout, uaddr2, val3) > +#endif > > /** > * futex_wait() - block on uaddr with optional timeout > * @timeout: relative timeout > */ > static inline int > -futex_wait(u_int32_t *uaddr, u_int32_t val, struct timespec *timeout, int opflags) > +futex_wait(u_int32_t *uaddr, u_int32_t val, struct timespec64 *timeout, int opflags) > { > return futex(uaddr, FUTEX_WAIT, val, timeout, NULL, 0, opflags); > } > @@ -74,7 +88,7 @@ futex_wake(u_int32_t *uaddr, int nr_wake, int opflags) > * futex_lock_pi() - block on uaddr as a PI mutex > */ > static inline int > -futex_lock_pi(u_int32_t *uaddr, struct timespec *timeout, int opflags) > +futex_lock_pi(u_int32_t *uaddr, struct timespec64 *timeout, int opflags) > { > return futex(uaddr, FUTEX_LOCK_PI, 0, timeout, NULL, 0, opflags); > } > @@ -111,7 +125,7 @@ futex_cmp_requeue(u_int32_t *uaddr, u_int32_t val, u_int32_t *uaddr2, int nr_wak > */ > static inline int > futex_wait_requeue_pi(u_int32_t *uaddr, u_int32_t val, u_int32_t *uaddr2, > - struct timespec *timeout, int opflags) > + struct timespec64 *timeout, int opflags) > { > return futex(uaddr, FUTEX_WAIT_REQUEUE_PI, val, timeout, uaddr2, 0, > opflags); > -- > 2.31.1 -- - Arnaldo