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Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.12.0 MIME-Version: 1.0 In-Reply-To: <20200909094914.29721-4-nborisov@suse.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable X-Provags-ID: V03:K1:HKp5K2htdxYQdj4Xqfr7AiFOVuYvpcd8Xj40NiwVm4E9HiUPY1G /5I1SYCg1RE6wuWtThQYxd6ycs4pt/m9c+9xfNIV+E9o3l8RKw72edr7QXksscoz7s40XFE fzFzOPaL0KIDtGMmthmPaEQWo/h3D7mj6Mk8/NpAetWWQXKhpcIS7slzAcbUQvZHvRbitre /nGhqsv1eYcUs0b/MBqqg== X-UI-Out-Filterresults: notjunk:1;V03:K0:TsK/WDX72wY=:hT1bYOKY07ntAthVOOhyrG 9GWK14Aaebj3z9WiRuxvYgm4xLN69Uf5ZDn7WT6PUKSsgZbo7cxB6e+kZesp7buzGavcqfEzx gEyg1PylolTdrOznm5aM16zCALdf34rtSM8QAIgEbZGIAGw+6WFSC1h0y7vsQ/x/3Gs5azrMD 0N/c2ijYiR+/APYW6HKPTTHsxUp02M7smFyUqa6ergCZN25NRKSHKZZRA7tBH5a12q2oxIvXZ Cs8Y9Wiz+gz7vnZalqNuwmtwWkt3d/RFF8ZZLeY1ni25PgPGfSTlicVxhRWuQF70g3c06EFrD eYG8yVAN5kWSWgjxHP1EO1SnfN1/S9zm0p74yhkGPO6CKZSRnCDQUYuKOmEbH/77K2FZfmjAY 1g42LIHi6Sdd86NOXe2EtE63noeI5TrEUWO0VH1EJhcAYPhVUDrSjYYSD9BBGZTbbb27K7viq +mkhNFUChC3DnsjirQzLlFqjOgzKiN6JvKKp+itPH1BpmCPpAVx8yW1YMPan0eVfVUBn93nvq ISmSK+dw+2RkUoGvdc0Nl8abYIsQlQky9Njw/3skKu/5RwuTERfhb3ksHNRb9E7BFDpsco16u uk+Zz1PNttNefMdUC/4uEndjBec5tUQtzw3+M3nVvPNWhTSPrL2kqNzEr30CG5Xdqv1xNwI89 SvqxJC4vpaOWxqnCJ4y6Bu17++hDr5M0xIoMWniRH1RkddsoG9Upc7leaxrVQSx6PI97wliEH XscdM+bTNPwgkQBQK0DBP7UeRB5NyuR/t9EAhYYPzJDsj3kSRsNxUQS3o/7fGzBxregCYuOXV lKVR/KP9QRD2pVxLHXPW106G+li71IG7QSuRlGP5Ly6Dx1/UnIfzQrNDRa52p3CpPgwplLODm +yCohLRjg7KZb4ST0H9Xr03ft52Zoc85a2DwK8LMFxNpa/Yd3oxn5KK6tpamOzGTr1sWPSHPa iuhoKiUsY364dUgmn3dYPbn/W0buo4zG3yBOrcOn0ZK7C7KVetF9QbHBg6/xIJtsZGpRMZw6Y K2cK+xD8jJixIZHv9H3ePwvsMz43jnpVjHs0Hs5mL4sJZpqlDJhKoEGF0CwbdtDSp5i/79fRM RL3o4eF4QxLEvQlsySx9ueCE01dx6Al5Yxh8jQTuG3tQPIWbVPG4x1uUUiLmrbOyaKHDegKY7 l/Qq92Ufgxz5zCaFtuSy/SFgnDtgrik7rwFuezE4zT/hfReKQ1nyCarigRKgvm/dSfc0vrXet gXuXpIZ0Ci4meZBaCmsAlgXmlI1drRXyU23WRJg== Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org On 2020/9/9 =E4=B8=8B=E5=8D=885:49, Nikolay Borisov wrote: > Metadata pages currently use __do_readpage to read metadata pages, > unfortunately this function is also used to deal with ordinary data > pages. This makes the metadata pages reading code to go through multiple > hoops in order to adhere to __do_readpage invariants. Most of these are > necessary for data pages which could be compressed. For metadata it's > enough to simply build a bio and submit it. > > To this effect simply call submit_extent_page directly from > read_extent_buffer_pages which is the only callpath used to populate > extent_buffers with data. This in turn enables further cleanups. This is awesome!!! And the code also looks pretty good to me. Reviewed-by: Qu Wenruo Just a note for further enhancement inlined below. > > Signed-off-by: Nikolay Borisov > --- > fs/btrfs/extent_io.c | 18 ++++++------------ > 1 file changed, 6 insertions(+), 12 deletions(-) > > diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c > index ac92c0ab1402..1789a7931312 100644 > --- a/fs/btrfs/extent_io.c > +++ b/fs/btrfs/extent_io.c > @@ -5575,20 +5575,14 @@ int read_extent_buffer_pages(struct extent_buffe= r *eb, int wait, int mirror_num) > } > > ClearPageError(page); > - err =3D __extent_read_full_page(page, > - btree_get_extent, &bio, > - mirror_num, &bio_flags, > - REQ_META); > + err =3D submit_extent_page(REQ_OP_READ | REQ_META, NULL, > + page, page_offset(page), PAGE_SIZE, 0, It would be better to enhance the comment for submit_extent_page() of @offset. It's in fact btrfs logical bytenr. For metadata, page_offset(page) is also the btrfs logical bytenr so it's completely fine. But it can be different for data inodes, so it's better to make it more clear in the comment. Thanks, Qu > + &bio, end_bio_extent_readpage, > + mirror_num, 0, 0, false); > if (err) { > ret =3D err; > - /* > - * We use &bio in above __extent_read_full_page, > - * so we ensure that if it returns error, the > - * current page fails to add itself to bio and > - * it's been unlocked. > - * > - * We must dec io_pages by ourselves. > - */ > + SetPageError(page); > + unlock_page(page); > atomic_dec(&eb->io_pages); > } > } else { >