From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mout.kundenserver.de (mout.kundenserver.de [212.227.126.134]) by sourceware.org (Postfix) with ESMTPS id CB4103857C62 for ; Tue, 26 Jan 2021 11:45:12 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org CB4103857C62 Received: from calimero.vinschen.de ([24.134.7.25]) by mrelayeu.kundenserver.de (mreue009 [212.227.15.167]) with ESMTPSA (Nemesis) id 1MAwPZ-1lFgWl3IKX-00BOZG for ; Tue, 26 Jan 2021 12:45:10 +0100 Received: by calimero.vinschen.de (Postfix, from userid 500) id 57F81A80D7F; Tue, 26 Jan 2021 12:45:10 +0100 (CET) Date: Tue, 26 Jan 2021 12:45:10 +0100 From: Corinna Vinschen To: cygwin-patches@cygwin.com Subject: Re: [PATCH v2 6/8] syscalls.cc: Expose shallow-pathconv unlink_nt Message-ID: <20210126114510.GL4393@calimero.vinschen.de> Reply-To: cygwin-patches@cygwin.com Mail-Followup-To: cygwin-patches@cygwin.com References: <20210115134534.13290-1-ben@wijen.net> <20210120161056.77784-7-ben@wijen.net> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20210120161056.77784-7-ben@wijen.net> X-Provags-ID: V03:K1:3YJPdULvZvZftL/Cpiy1wUAoUmeMQFJ0D8+r40Iq5y53nlZEAqO SWOOJIJECUb5uvV/rNF/XUHQhIlG5KvAj5Bk+kdhV9Zfk4SzNFbwH1Fz2SFyZiHpiGmqJtg T7/+c9NxSwqE3b80kKL2LXonqg5m7ANehjsVXs2TFX+a9AfG6mk33jiWzBe86koaQQuSQ6w mvL2LoYZqXeHAxjIbbhFw== X-UI-Out-Filterresults: notjunk:1;V03:K0:vj/xxWHlM9U=:MkvI5CBcw5nI+yFclTHi1E H3IiP1cLKCUiaMkCCdcHYNUBNYsh/6e0JB5x4aXusED72I9k2gcFuwqGD4JJcc2ah70ZEMSEQ MTrgOn1++mx+65yKaVRfwqXFe7OZ6WTgVR0uhC+OGJQsNIEW7ZYxfx7U9S9h8FEqeRwfpCxGm /hdzjI8208OK1zq20UzoPyy0lYT1TyAOm9xdO0LVL8myoFGjLjCTEolANqAWWROW3OqdGjzWM hvuqQUUBNFUhf7HbjMm4f1mdUcINTIydl6kcGsxHeCaWqToCbd2ufa9WpS/UQyv0j+lckW+yg P35RiN2+HrqzQC5gzDt1jQBIeEC6pND91BGbpHeXXqv87Y3DjBB7T8akc1quq0re+hE6eT3uD 2oqyk+JIjzdgpknK/xVStmY8VrbO2HfjS+XQzdTGlrKtRGM9h5eon6ryEKBV0Bu2b2qf7ZZBy Xr6JW8TDew== X-Spam-Status: No, score=-106.9 required=5.0 tests=BAYES_00, GIT_PATCH_0, GOOD_FROM_CORINNA_CYGWIN, JMQ_SPF_NEUTRAL, KAM_DMARC_NONE, KAM_DMARC_STATUS, RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H2, SPF_HELO_NONE, SPF_NEUTRAL, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: cygwin-patches@cygwin.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: Cygwin core component patch submission and discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 26 Jan 2021 11:45:14 -0000 On Jan 20 17:10, Ben Wijen wrote: > Not having to query file information improves unlink speed. > --- > winsup/cygwin/syscalls.cc | 78 ++++++++++++++++++++++++++------------- > 1 file changed, 52 insertions(+), 26 deletions(-) > > diff --git a/winsup/cygwin/syscalls.cc b/winsup/cygwin/syscalls.cc > index ab0c4c2d6..b5ab6ac5e 100644 > --- a/winsup/cygwin/syscalls.cc > +++ b/winsup/cygwin/syscalls.cc > @@ -1272,6 +1272,28 @@ _unlink_ntpc_ (path_conv& pc, bool shareable) > return status; > } > > +NTSTATUS > +unlink_nt (const char *ourname, ULONG eflags) > +{ > + uint32_t opt = PC_SYM_NOFOLLOW | PC_SKIP_SYM_CHECK | PC_SKIP_FS_CHECK; > + if (!(eflags & FILE_NON_DIRECTORY_FILE)) > + opt &= ~PC_SKIP_FS_CHECK; > + > + path_conv pc (ourname, opt, NULL); > + if (pc.error || pc.isspecial ()) > + return STATUS_CANNOT_DELETE; > + > + OBJECT_ATTRIBUTES attr; > + PUNICODE_STRING ntpath = pc.get_nt_native_path (); > + InitializeObjectAttributes(&attr, ntpath, 0, NULL, NULL); > + NTSTATUS status = _unlink_nt (&attr, eflags); Sorry again, but I don't see the advantage of not using the intelligence already collected in path_conv by neglecting to call the unlink variation not using them. It's also unclear to me, why the new code doesn't try_to_bin right away, rather than stomping ahead and falling back to the current code for each such file. In an rm -rf on a file hirarchy used by other users, you could end up with a much slower operation. Wouldn't it make more sense to streamline the existing _unlink_nt? I don't claim it's the most streamlined way to delete files, but at least it has documented workarounds for problems encountered on the way, already. Corinna