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Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kR02E-0006H5-1x; Fri, 09 Oct 2020 21:34:42 +0000 Received: from mail.kernel.org ([198.145.29.99]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kR02A-0006FZ-Ca; Fri, 09 Oct 2020 21:34:39 +0000 Received: from sol.localdomain (172-10-235-113.lightspeed.sntcca.sbcglobal.net [172.10.235.113]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 44F7C21D6C; Fri, 9 Oct 2020 21:34:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1602279277; bh=af4HYKUXjfzQEnpRkoqrLOtb/VuZgD2GaaA85DESAB8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=mAKgXcy5CifgRYN2i2C2c94+Jg5oLVaoZk49jTIFxseeqdMtEOOqP5cL66hXhKNTI eNSQDBkgqgAc1Wd7XIXje+joGiBVI4yatMIDb1+kpBlSLeGvwRiFFGcw+A+0IeryZM wi38bfOOqpr1rBlahq6SJoGGKG4xvvKCLXOhXA9s= Date: Fri, 9 Oct 2020 14:34:34 -0700 From: Eric Biggers To: ira.weiny@intel.com Subject: Re: [PATCH RFC PKS/PMEM 22/58] fs/f2fs: Utilize new kmap_thread() Message-ID: <20201009213434.GA839@sol.localdomain> References: <20201009195033.3208459-1-ira.weiny@intel.com> <20201009195033.3208459-23-ira.weiny@intel.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20201009195033.3208459-23-ira.weiny@intel.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201009_173438_586100_1B1C9D0F X-CRM114-Status: GOOD ( 18.01 ) X-BeenThere: linux-mtd@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-aio@kvack.org, linux-efi@vger.kernel.org, kvm@vger.kernel.org, linux-doc@vger.kernel.org, Peter Zijlstra , linux-mmc@vger.kernel.org, Dave Hansen , dri-devel@lists.freedesktop.org, linux-mm@kvack.org, target-devel@vger.kernel.org, linux-mtd@lists.infradead.org, linux-kselftest@vger.kernel.org, Thomas Gleixner , drbd-dev@lists.linbit.com, devel@driverdev.osuosl.org, linux-cifs@vger.kernel.org, linux-nilfs@vger.kernel.org, linux-scsi@vger.kernel.org, linux-nvdimm@lists.01.org, linux-rdma@vger.kernel.org, x86@kernel.org, amd-gfx@lists.freedesktop.org, linux-afs@lists.infradead.org, cluster-devel@redhat.com, Ingo Molnar , intel-wired-lan@lists.osuosl.org, kexec@lists.infradead.org, xen-devel@lists.xenproject.org, linux-ext4@vger.kernel.org, bpf@vger.kernel.org, Dan Williams , Fenghua Yu , intel-gfx@lists.freedesktop.org, ecryptfs@vger.kernel.org, linux-um@lists.infradead.org, reiserfs-devel@vger.kernel.org, linux-block@vger.kernel.org, linux-bcache@vger.kernel.org, Borislav Petkov , Andy Lutomirski , Jaegeuk Kim , ceph-devel@vger.kernel.org, io-uring@vger.kernel.org, linux-cachefs@redhat.com, linux-nfs@vger.kernel.org, linux-ntfs-dev@lists.sourceforge.net, netdev@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, samba-technical@lists.samba.org, linux-kernel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-fsdevel@vger.kernel.org, Andrew Morton , linux-erofs@lists.ozlabs.org, linux-btrfs@vger.kernel.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-mtd" Errors-To: linux-mtd-bounces+linux-mtd=archiver.kernel.org@lists.infradead.org On Fri, Oct 09, 2020 at 12:49:57PM -0700, ira.weiny@intel.com wrote: > From: Ira Weiny > > The kmap() calls in this FS are localized to a single thread. To avoid > the over head of global PKRS updates use the new kmap_thread() call. > > Cc: Jaegeuk Kim > Cc: Chao Yu > Signed-off-by: Ira Weiny > --- > fs/f2fs/f2fs.h | 8 ++++---- > 1 file changed, 4 insertions(+), 4 deletions(-) > > diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h > index d9e52a7f3702..ff72a45a577e 100644 > --- a/fs/f2fs/f2fs.h > +++ b/fs/f2fs/f2fs.h > @@ -2410,12 +2410,12 @@ static inline struct page *f2fs_pagecache_get_page( > > static inline void f2fs_copy_page(struct page *src, struct page *dst) > { > - char *src_kaddr = kmap(src); > - char *dst_kaddr = kmap(dst); > + char *src_kaddr = kmap_thread(src); > + char *dst_kaddr = kmap_thread(dst); > > memcpy(dst_kaddr, src_kaddr, PAGE_SIZE); > - kunmap(dst); > - kunmap(src); > + kunmap_thread(dst); > + kunmap_thread(src); > } Wouldn't it make more sense to switch cases like this to kmap_atomic()? The pages are only mapped to do a memcpy(), then they're immediately unmapped. - Eric ______________________________________________________ Linux MTD discussion mailing list http://lists.infradead.org/mailman/listinfo/linux-mtd/