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prefer-encrypt=mutual; keydata= mQENBFnVga8BCACyhFP3ExcTIuB73jDIBA/vSoYcTyysFQzPvez64TUSCv1SgXEByR7fju3o 8RfaWuHCnkkea5luuTZMqfgTXrun2dqNVYDNOV6RIVrc4YuG20yhC1epnV55fJCThqij0MRL 1NxPKXIlEdHvN0Kov3CtWA+R1iNN0RCeVun7rmOrrjBK573aWC5sgP7YsBOLK79H3tmUtz6b 9Imuj0ZyEsa76Xg9PX9Hn2myKj1hfWGS+5og9Va4hrwQC8ipjXik6NKR5GDV+hOZkktU81G5 gkQtGB9jOAYRs86QG/b7PtIlbd3+pppT0gaS+wvwMs8cuNG+Pu6KO1oC4jgdseFLu7NpABEB AAG0IlF1IFdlbnJ1byA8cXV3ZW5ydW8uYnRyZnNAZ214LmNvbT6JAU4EEwEIADgCGwMFCwkI BwIGFQgJCgsCBBYCAwECHgECF4AWIQQt33LlpaVbqJ2qQuHCPZHzoSX+qAUCXZw1oQAKCRDC PZHzoSX+qCY6CACd+mWu3okGwRKXju6bou+7VkqCaHTdyXwWFTsr+/0ly5nUdDtT3yEVggPJ 3VP70wjlrxUjNjFb6iIvGYxiPOrop1NGwGYvQktgRhaIhALG6rPoSSAhGNjwGVRw0km0PlIN D29BTj/lYEk+jVM1YL0QLgAE1AI3krihg/lp/fQT53wLhR8YZIF8ETXbClQG1vJ0cllPuEEv efKxRyiTSjB+PsozSvYWhXsPeJ+KKjFen7ebE5reQTPFzSHctCdPnoR/4jSPlnTlnEvLeqcD ZTuKfQe1gWrPeevQzgCtgBF/WjIOeJs41klnYzC3DymuQlmFubss0jShLOW8eSOOWhLRuQEN BFnVga8BCACqU+th4Esy/c8BnvliFAjAfpzhI1wH76FD1MJPmAhA3DnX5JDORcgaCbPEwhLj 1xlwTgpeT+QfDmGJ5B5BlrrQFZVE1fChEjiJvyiSAO4yQPkrPVYTI7Xj34FnscPj/IrRUUka 68MlHxPtFnAHr25VIuOS41lmYKYNwPNLRz9Ik6DmeTG3WJO2BQRNvXA0pXrJH1fNGSsRb+pK EKHKtL1803x71zQxCwLh+zLP1iXHVM5j8gX9zqupigQR/Cel2XPS44zWcDW8r7B0q1eW4Jrv 0x19p4P923voqn+joIAostyNTUjCeSrUdKth9jcdlam9X2DziA/DHDFfS5eq4fEvABEBAAGJ ATwEGAEIACYCGwwWIQQt33LlpaVbqJ2qQuHCPZHzoSX+qAUCXZw1rgUJCWpOfwAKCRDCPZHz oSX+qFcEB/95cs8cM1OQdE/GgOfCGxwgckMeWyzOR7bkAWW0lDVp2hpgJuxBW/gyfmtBnUai fnggx3EE3ev8HTysZU9q0h+TJwwJKGv6sUc8qcTGFDtavnnl+r6xDUY7A6GvXEsSoCEEynby 72byGeSovfq/4AWGNPBG1L61Exl+gbqfvbECP3ziXnob009+z9I4qXodHSYINfAkZkA523JG ap12LndJeLk3gfWNZfXEWyGnuciRGbqESkhIRav8ootsCIops/SqXm0/k+Kcl4gGUO/iD/T5 oagaDh0QtOd8RWSMwLxwn8uIhpH84Q4X1LadJ5NCgGa6xPP5qqRuiC+9gZqbq4Nj Message-ID: Date: Wed, 1 Jul 2020 18:58:55 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.9.0 MIME-Version: 1.0 In-Reply-To: <20200701092449.19545-1-robbieko@synology.com> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="VuMET84Vz89JlParkwtQUenoeOW8TScbu" X-Provags-ID: V03:K1:y64oBjbiym5VBNbAB25snQS3awJBp4dYes51olvoBzUYIqoh5Hl o7cuZuO27Ix/o2aRtSt02jhLojgVPRFk4msCLXOkG0npmjhYXk1qBDvS7r9476uo5xy0RcJ GtTnGo49eFjVy2HeYC1fMAK28am/0TzB/Tl+7AqGqx/SFrUwC9ug603EDnkKrmIVCT3OPI1 aBJPlwyIBLZjZStg9u6Zw== X-UI-Out-Filterresults: notjunk:1;V03:K0:AcXrP/vefaE=:XnMyc8BsoUhZNJ0gO1N0PA AmmQO8IYG52QbLNRyu09apfX/xrI1h4rXRy3uLF/8LDijQkYMWHqN6v0ED53EkJXMI5EjeriZ vzJzwKcJmp8JnM16B1NBYWAZFKm9iImU2Lhaw20bOkqpCd3WQhx92WtUnddrE7B11Hw9uYo1I ifshScHpUdUp3ViWiE3rsoiRzuBcf/uqIztWSrBelw7I4loWS2IS/QBkM/gljMhSG4eLoSvSz n64U7Cv1dkIIiYx3f3Yo0Ysz4Ga1EOsm+Nacq21Zvv6QGNomxHg+4OFtWSyuPr4pBlnixYLoQ DzGK+8qiDOu2RBQUVKkeOGfYAudqK5xihoq8gk7fMEDfTX9inS6AzjRHxjcQfPccFqrxLFu+v G65KHVWtFOR7hYswae70rWr+pQ/qy0wX9df0qQ8nYpbIrHE04azsrIKVgf8utSX188OTy7OyN sdljNUuJJFmXYnek9FZlj2U8uHUe2WhjljJBI+Oxj/3niqPDwmj2xbNvfYXZC3zNHTqSWIqL8 ixr4B3o+ABRO9YnBSRKnGNO4HY4XJtqCpFPIc+/Xc1ra23JqJ4P9MOphO+jO97HEbsQnATQxY 7IsyZeDA2CGhD8kg61VGWJ/Gc1T2Y6j4YDEOdC6L2H9Ly2Dgpl94itlGVfW3cmQcylf8xVFnn loJcsl32v/10tQ9UmRSjFF6GH/lTM5NYA+NYxyS20y6tp3NPdE6KmBM9SV6O4qeAHU3r/pWun jM8y1XM73nvwdFiBJ7dXZORII2aAhcAjIssIDNVkMMTnCTYwk1mVG2HKYvrtlQlJSOfn8/soD bX6lxaOKQLqpWJA0TjDq02vnMMCEdwYoq1h5Rc9K6rsyG9xMBgdrpxeuKz7KKhE0huKD6jYvf RaMJ/C2ji3AaCBXSOefJ6yFtQWEDJo1PO2GSKlVK15RG3615iWepTU0ruKTabAfE7ll+fpIP4 AwjXvBwlnQGu0Cexv8x5O3XOk8pm4O4aQYwn/wF/a0C0R9Dyg4Mk/JnlVLWNt9SwLQa29Waev r+HpTczh7bUsVmyKmVeqqp+o2dfXNDAM4O/een60kh9j3PRvXMKmTFFmp28E9l92Sm9Iddo3t LKkPyOhYWnv4OhbB3u5Ig73+msD6tWyaZZAGSNnrIS5A9xdKOiPbXQ2dgkw0xRK6hqn6aEyG1 esFGxu3Sl+w22mXUVts2i64ExmicKlKQK75NHWX06K2ZG4Dl50hUf1c0PsdLp7I1CmTiy8bFb 9JiO92UTguF5AybOFZzJuN5LOx8ZUy3d14ZvkXA== Sender: fstests-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: fstests@vger.kernel.org This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --VuMET84Vz89JlParkwtQUenoeOW8TScbu Content-Type: multipart/mixed; boundary="IP1noLLq6loH1UJmvV9ZZONH2Zj5AGJLy" --IP1noLLq6loH1UJmvV9ZZONH2Zj5AGJLy Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable On 2020/7/1 =E4=B8=8B=E5=8D=885:24, robbieko wrote: > From: Robbie Ko >=20 > When mounting, we always need to read the whole chunk tree, > when there are too many chunk items, most of the time is > spent on btrfs_read_chunk_tree, because we only read one > leaf at a time. Well, under most case it would be btrfs_read_block_groups(), unless all data chunks are very compact with just several large data extents. >=20 > We fix this by adding a new readahead mode READA_FORWARD_FORCE, > which reads all the leaves after the key in the node when > reading a level 1 node. >=20 > Signed-off-by: Robbie Ko > --- > fs/btrfs/ctree.c | 7 +++++-- > fs/btrfs/ctree.h | 2 +- > fs/btrfs/volumes.c | 1 + > 3 files changed, 7 insertions(+), 3 deletions(-) >=20 > diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c > index 3a7648bff42c..abb9108e2d7d 100644 > --- a/fs/btrfs/ctree.c > +++ b/fs/btrfs/ctree.c > @@ -2194,7 +2194,7 @@ static void reada_for_search(struct btrfs_fs_info= *fs_info, > if (nr =3D=3D 0) > break; > nr--; > - } else if (path->reada =3D=3D READA_FORWARD) { > + } else if (path->reada =3D=3D READA_FORWARD || path->reada =3D=3D RE= ADA_FORWARD_FORCE) { > nr++; > if (nr >=3D nritems) > break; > @@ -2205,12 +2205,15 @@ static void reada_for_search(struct btrfs_fs_in= fo *fs_info, > break; > } > search =3D btrfs_node_blockptr(node, nr); > - if ((search <=3D target && target - search <=3D 65536) || > + if ((path->reada =3D=3D READA_FORWARD_FORCE) || > + (search <=3D target && target - search <=3D 65536) || > (search > target && search - target <=3D 65536)) { > readahead_tree_block(fs_info, search); > nread +=3D blocksize; > } > nscan++; > + if (path->reada =3D=3D READA_FORWARD_FORCE) > + continue; > if ((nread > 65536 || nscan > 32)) > break; > } > diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h > index d404cce8ae40..808bcbdc9530 100644 > --- a/fs/btrfs/ctree.h > +++ b/fs/btrfs/ctree.h > @@ -353,7 +353,7 @@ struct btrfs_node { > * The slots array records the index of the item or block pointer > * used while walking the tree. > */ > -enum { READA_NONE, READA_BACK, READA_FORWARD }; > +enum { READA_NONE, READA_BACK, READA_FORWARD, READA_FORWARD_FORCE }; > struct btrfs_path { > struct extent_buffer *nodes[BTRFS_MAX_LEVEL]; > int slots[BTRFS_MAX_LEVEL]; > diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c > index 0d6e785bcb98..78fd65abff69 100644 > --- a/fs/btrfs/volumes.c > +++ b/fs/btrfs/volumes.c > @@ -7043,6 +7043,7 @@ int btrfs_read_chunk_tree(struct btrfs_fs_info *f= s_info) > path =3D btrfs_alloc_path(); > if (!path) > return -ENOMEM; > + path->reada =3D READA_FORWARD_FORCE; Why not just use regular forward readahead? Mind to share the reason here? Just to force reada for all tree leaves? Thanks, Qu > =20 > /* > * uuid_mutex is needed only if we are mounting a sprout FS >=20 --IP1noLLq6loH1UJmvV9ZZONH2Zj5AGJLy-- --VuMET84Vz89JlParkwtQUenoeOW8TScbu Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEELd9y5aWlW6idqkLhwj2R86El/qgFAl78bG8ACgkQwj2R86El /qiHdgf/ev9HZD/sxXKisxkr0vpKlEBQ07pCRnSQLINf3C/MDuaXxgSBSHxyIbDl R7Od77JHtVCHwtibm5OYFQCC4SueRPMLLRYVr8VifV4+ZZFOR1y4Qd7Qmu9rhB6Q 5Wpz/1UGpzdJV0S11D6aHJXbi2NS2+mQppOMyPNrpfd8wuckZBjr5l61PE6yQaUg MY93ZI85GmyXDMv3vGn4tUtpknCXyz2UruIAdNRzvRrkQIeLQFtbyfUqGicVKbTP xBQeD3dzNqJGjRSHw1PM5AO4eo5+vNFX410tao1GVunJ+uBVMEyHnNjEWgfbzbf7 hcpOHjeTkub06eb0PDxjnu+t37dPug== =3Hhr -----END PGP SIGNATURE----- --VuMET84Vz89JlParkwtQUenoeOW8TScbu--