From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id 65514210C9968 for ; Wed, 30 May 2018 20:39:23 -0700 (PDT) Date: Wed, 30 May 2018 23:39:19 -0400 From: Mike Snitzer Subject: Re: [patch 4/4] dm-writecache: use new API for flushing Message-ID: <20180531033919.GA88973@redhat.com> References: <20180530131623.GB2106@redhat.com> <20180530132647.GB5157@redhat.com> <20180530135421.GA81788@redhat.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: linux-nvdimm-bounces@lists.01.org Sender: "Linux-nvdimm" To: Mikulas Patocka Cc: device-mapper development , linux-nvdimm List-ID: On Wed, May 30 2018 at 10:09P -0400, Mikulas Patocka wrote: > And what about this? > #define WC_MODE_PMEM(wc) ((wc)->pmem_mode) > > The code that I had just allowed the compiler to optimize out > persistent-memory code if we have DM_WRITECACHE_ONLY_SSD defined - and you > deleted it. > > Most architectures don't have persistent memory and the dm-writecache > driver could work in ssd-only mode on them. On these architectures, I > define > #define WC_MODE_PMEM(wc) false > - and the compiler will just automatically remove the tests for that > condition and the unused branch. It does also eliminate unused static > functions. Here is the patch that I just folded into the rebased version of dm-writecache now in the dm-4.18 branch. (I rebased ontop of Jens' latest block tree for 4.18 that now includes the mempool_init changes, etc.) --- drivers/md/dm-writecache.c | 17 +++++++++++++++-- 1 file changed, 15 insertions(+), 2 deletions(-) diff --git a/drivers/md/dm-writecache.c b/drivers/md/dm-writecache.c index fcbfaf7c27ec..691b5ffb799f 100644 --- a/drivers/md/dm-writecache.c +++ b/drivers/md/dm-writecache.c @@ -34,13 +34,21 @@ #define BITMAP_GRANULARITY PAGE_SIZE #endif +#if defined(CONFIG_ARCH_HAS_PMEM_API) && IS_ENABLED(CONFIG_DAX_DRIVER) +#define DM_WRITECACHE_HAS_PMEM +#endif + +#ifdef DM_WRITECACHE_HAS_PMEM #define pmem_assign(dest, src) \ do { \ typeof(dest) uniq = (src); \ memcpy_flushcache(&(dest), &uniq, sizeof(dest)); \ } while (0) +#else +#define pmem_assign(dest, src) ((dest)) = (src)) +#endif -#if defined(__HAVE_ARCH_MEMCPY_MCSAFE) && defined(CONFIG_ARCH_HAS_PMEM_API) +#if defined(__HAVE_ARCH_MEMCPY_MCSAFE) && defined(DM_WRITECACHE_HAS_PMEM) #define DM_WRITECACHE_HANDLE_HARDWARE_ERRORS #endif @@ -87,8 +95,13 @@ struct wc_entry { #endif }; +#ifdef DM_WRITECACHE_HAS_PMEM #define WC_MODE_PMEM(wc) ((wc)->pmem_mode) #define WC_MODE_FUA(wc) ((wc)->writeback_fua) +#else +#define WC_MODE_PMEM(wc) false +#define WC_MODE_FUA(wc) false +#endif #define WC_MODE_SORT_FREELIST(wc) (!WC_MODE_PMEM(wc)) struct dm_writecache { @@ -1857,7 +1870,7 @@ static int writecache_ctr(struct dm_target *ti, unsigned argc, char **argv) if (!strcasecmp(string, "s")) { wc->pmem_mode = false; } else if (!strcasecmp(string, "p")) { -#if defined(CONFIG_ARCH_HAS_PMEM_API) && IS_ENABLED(CONFIG_DAX_DRIVER) +#ifdef DM_WRITECACHE_HAS_PMEM wc->pmem_mode = true; wc->writeback_fua = true; #else -- 2.15.0 _______________________________________________ Linux-nvdimm mailing list Linux-nvdimm@lists.01.org https://lists.01.org/mailman/listinfo/linux-nvdimm