Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261682AbUFBKoO (ORCPT ); Wed, 2 Jun 2004 06:44:14 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261693AbUFBKoO (ORCPT ); Wed, 2 Jun 2004 06:44:14 -0400 Received: from natsmtp00.rzone.de ([81.169.145.165]:17645 "EHLO natsmtp00.rzone.de") by vger.kernel.org with ESMTP id S261682AbUFBKoG (ORCPT ); Wed, 2 Jun 2004 06:44:06 -0400 Message-ID: <40BDAD3C.3030103@giga-stream.de> Date: Wed, 02 Jun 2004 12:34:36 +0200 From: "Ihar 'Philips' Filipau" Organization: Giga Stream User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.6) Gecko/20040116 X-Accept-Language: en-us, en MIME-Version: 1.0 To: Mitchell Blank Jr CC: netdev@oss.sgi.com, Linux Kernel Mailing List Subject: Re: e1000 question References: <40BD8E49.3070605@giga-stream.de> <20040602103027.GA74881@gaz.sfgoth.com> In-Reply-To: <20040602103027.GA74881@gaz.sfgoth.com> Content-Type: multipart/signed; protocol="application/x-pkcs7-signature"; micalg=sha1; boundary="------------ms050103070102000008040302" Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6947 Lines: 122 This is a cryptographically signed message in MIME format. --------------ms050103070102000008040302 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Thanks, Mitch! That explains everything. Went reading pci_alloc_consistent()'s RTFM. That is exactly what I was missing in couple of my drivers. Mitchell Blank Jr wrote: > Ihar 'Philips' Filipau wrote: > >> Functions e1000_clean_{t,r}x_irq are very similar: both of them are >>checking descriptor flag updated by nic. >> Host CPU, obviously, to perform this check, will cache descriptor. >> If, say e1000_clean_rx_irq() will be called twice in short time >>range, I expect that it can miss change of the flag, since old flag may >>still sit in host CPU cache. > > > Please see Documentation/DMA-mapping.txt; especially the part starting > at "There are two types of DMA mappings..." Ring buffers are allocated > as "consistent" DMA memory. > > For most architectures this will mean that the cache hardware snoops the > PCI bus and automatically invalidates cache lines as they are written to. > For architectures that can't do that then Linux will mark those memory > regions uncacheable. > -- Johnson's law: Systems resemble the organizations that create them. -- ___ ___ Ihar 'Philips' Filipau \ / Sr. Software Developer Tel: +49 681 959 16 0 \ / GIGA STREAM Fax: +49 681 959 16 100 \/ Konrad Zuse Strasse 7 Mobile: +49 173 39 462 49 /\ 66115 Saarbruecken email: ifilipau@giga-stream.de / \ Germany www: http://www.giga-stream.de ___/ \___ Switching for success --------------ms050103070102000008040302 Content-Type: application/x-pkcs7-signature; name="smime.p7s" Content-Transfer-Encoding: base64 Content-Disposition: attachment; filename="smime.p7s" Content-Description: S/MIME Cryptographic Signature MIAGCSqGSIb3DQEHAqCAMIACAQExCzAJBgUrDgMCGgUAMIAGCSqGSIb3DQEHAQAAoIIJXDCC AwwwggJ1oAMCAQICAwp5RzANBgkqhkiG9w0BAQQFADCBkjELMAkGA1UEBhMCWkExFTATBgNV BAgTDFdlc3Rlcm4gQ2FwZTESMBAGA1UEBxMJQ2FwZSBUb3duMQ8wDQYDVQQKEwZUaGF3dGUx HTAbBgNVBAsTFENlcnRpZmljYXRlIFNlcnZpY2VzMSgwJgYDVQQDEx9QZXJzb25hbCBGcmVl bWFpbCBSU0EgMjAwMC44LjMwMB4XDTAzMDgwNDEyMDI1OVoXDTA0MDgwMzEyMDI1OVowSTEf MB0GA1UEAxMWVGhhd3RlIEZyZWVtYWlsIE1lbWJlcjEmMCQGCSqGSIb3DQEJARYXaWZpbGlw YXVAZ2lnYS1zdHJlYW0uZGUwggEiMA0GCSqGSIb3DQEBAQUAA4IBDwAwggEKAoIBAQCh23lX NmvjlqAwzhanhztIary04F8dGaAt4ABMEMiNf+XD353lzpIHcHVzTH0OY4c9LtFNbt5V+XZT JoENrCLlDDCerzYgVNEejB173dpMQW1mAoYgl5AJZArvjgojcSKWG+BMaD2ozo3NVAPMAkwD Zhk25/WtbqN4UDf2mGljaU4/SETZKUJ+pNeeiXoz2KHlkJyZ8zubjJuR7xf5hPMpfsV+ePHI ohDZAFlM58D6wpgbDp8DO5CL4dnqSLeW+xCv+ETDIATu8B80Cv4QifhTWIJsosEzFP6CljUE hdBDbr3sgPTdVbTewTptD4hKodp67/2WjWsS6DMZwZl7oyTTAgMBAAGjNDAyMCIGA1UdEQQb MBmBF2lmaWxpcGF1QGdpZ2Etc3RyZWFtLmRlMAwGA1UdEwEB/wQCMAAwDQYJKoZIhvcNAQEE BQADgYEAXUjvmMsvEKRjvE8E2xjjymWYARwQ9fj/jbf/bpEy+fxub4It78X93RyBEazIciky +H3ZVmjTUH+dnxzYpBrEztVIuKDsCkuF5++j+NXDsELsuOFNX+1Z/YZ4ol5rJaensb/ZwflA byaeNV7+nl7qUgPxTanF16QDv13+EumlMdUwggMMMIICdaADAgECAgMKeUcwDQYJKoZIhvcN AQEEBQAwgZIxCzAJBgNVBAYTAlpBMRUwEwYDVQQIEwxXZXN0ZXJuIENhcGUxEjAQBgNVBAcT CUNhcGUgVG93bjEPMA0GA1UEChMGVGhhd3RlMR0wGwYDVQQLExRDZXJ0aWZpY2F0ZSBTZXJ2 aWNlczEoMCYGA1UEAxMfUGVyc29uYWwgRnJlZW1haWwgUlNBIDIwMDAuOC4zMDAeFw0wMzA4 MDQxMjAyNTlaFw0wNDA4MDMxMjAyNTlaMEkxHzAdBgNVBAMTFlRoYXd0ZSBGcmVlbWFpbCBN ZW1iZXIxJjAkBgkqhkiG9w0BCQEWF2lmaWxpcGF1QGdpZ2Etc3RyZWFtLmRlMIIBIjANBgkq hkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAodt5VzZr45agMM4Wp4c7SGq8tOBfHRmgLeAATBDI jX/lw9+d5c6SB3B1c0x9DmOHPS7RTW7eVfl2UyaBDawi5Qwwnq82IFTRHowde93aTEFtZgKG IJeQCWQK744KI3EilhvgTGg9qM6NzVQDzAJMA2YZNuf1rW6jeFA39phpY2lOP0hE2SlCfqTX nol6M9ih5ZCcmfM7m4ybke8X+YTzKX7FfnjxyKIQ2QBZTOfA+sKYGw6fAzuQi+HZ6ki3lvsQ r/hEwyAE7vAfNAr+EIn4U1iCbKLBMxT+gpY1BIXQQ2697ID03VW03sE6bQ+ISqHaeu/9lo1r EugzGcGZe6Mk0wIDAQABozQwMjAiBgNVHREEGzAZgRdpZmlsaXBhdUBnaWdhLXN0cmVhbS5k ZTAMBgNVHRMBAf8EAjAAMA0GCSqGSIb3DQEBBAUAA4GBAF1I75jLLxCkY7xPBNsY48plmAEc EPX4/423/26RMvn8bm+CLe/F/d0cgRGsyHIpMvh92VZo01B/nZ8c2KQaxM7VSLig7ApLhefv o/jVw7BC7LjhTV/tWf2GeKJeayWnp7G/2cH5QG8mnjVe/p5e6lID8U2pxdekA79d/hLppTHV MIIDODCCAqGgAwIBAgIQZkVyt8x09c9jdkWE0C6RATANBgkqhkiG9w0BAQQFADCB0TELMAkG A1UEBhMCWkExFTATBgNVBAgTDFdlc3Rlcm4gQ2FwZTESMBAGA1UEBxMJQ2FwZSBUb3duMRow GAYDVQQKExFUaGF3dGUgQ29uc3VsdGluZzEoMCYGA1UECxMfQ2VydGlmaWNhdGlvbiBTZXJ2 aWNlcyBEaXZpc2lvbjEkMCIGA1UEAxMbVGhhd3RlIFBlcnNvbmFsIEZyZWVtYWlsIENBMSsw KQYJKoZIhvcNAQkBFhxwZXJzb25hbC1mcmVlbWFpbEB0aGF3dGUuY29tMB4XDTAwMDgzMDAw MDAwMFoXDTA0MDgyNzIzNTk1OVowgZIxCzAJBgNVBAYTAlpBMRUwEwYDVQQIEwxXZXN0ZXJu IENhcGUxEjAQBgNVBAcTCUNhcGUgVG93bjEPMA0GA1UEChMGVGhhd3RlMR0wGwYDVQQLExRD ZXJ0aWZpY2F0ZSBTZXJ2aWNlczEoMCYGA1UEAxMfUGVyc29uYWwgRnJlZW1haWwgUlNBIDIw MDAuOC4zMDCBnzANBgkqhkiG9w0BAQEFAAOBjQAwgYkCgYEA3jMypmPHCSVFPtJueCdngcXa iBmClw7jRCmKYzUqbXA8+tyu9+50bzC8M5B/+TRxoKNtmPHDT6Jl2w36S/HW3WGl+YXNVZo1 Gp2Sdagnrthy+boC9tewkd4c6avgGAOofENCUFGHgzzwObSbVIoTh/+zm51JZgAtCYnslGvp oWkCAwEAAaNOMEwwKQYDVR0RBCIwIKQeMBwxGjAYBgNVBAMTEVByaXZhdGVMYWJlbDEtMjk3 MBIGA1UdEwEB/wQIMAYBAf8CAQAwCwYDVR0PBAQDAgEGMA0GCSqGSIb3DQEBBAUAA4GBADGx S0dd+QFx5fVTbF151j2YwCYTYoEipxL4IpXoG0m3J3sEObr85vIk65H6vewNKjj3UFWobPcN rUwbvAP0teuiR59sogxYjTFCCRFssBpp0SsSskBdavl50OouJd2K5PzbDR+dAvNa28o89kTq JmmHf0iezqWf54TYyWJirQXGMYID1TCCA9ECAQEwgZowgZIxCzAJBgNVBAYTAlpBMRUwEwYD VQQIEwxXZXN0ZXJuIENhcGUxEjAQBgNVBAcTCUNhcGUgVG93bjEPMA0GA1UEChMGVGhhd3Rl MR0wGwYDVQQLExRDZXJ0aWZpY2F0ZSBTZXJ2aWNlczEoMCYGA1UEAxMfUGVyc29uYWwgRnJl ZW1haWwgUlNBIDIwMDAuOC4zMAIDCnlHMAkGBSsOAwIaBQCgggIPMBgGCSqGSIb3DQEJAzEL BgkqhkiG9w0BBwEwHAYJKoZIhvcNAQkFMQ8XDTA0MDYwMjEwMzQzNlowIwYJKoZIhvcNAQkE MRYEFJv4LpGyY/ToFFenFqRYT+Yaw6+1MFIGCSqGSIb3DQEJDzFFMEMwCgYIKoZIhvcNAwcw DgYIKoZIhvcNAwICAgCAMA0GCCqGSIb3DQMCAgFAMAcGBSsOAwIHMA0GCCqGSIb3DQMCAgEo MIGrBgkrBgEEAYI3EAQxgZ0wgZowgZIxCzAJBgNVBAYTAlpBMRUwEwYDVQQIEwxXZXN0ZXJu IENhcGUxEjAQBgNVBAcTCUNhcGUgVG93bjEPMA0GA1UEChMGVGhhd3RlMR0wGwYDVQQLExRD ZXJ0aWZpY2F0ZSBTZXJ2aWNlczEoMCYGA1UEAxMfUGVyc29uYWwgRnJlZW1haWwgUlNBIDIw MDAuOC4zMAIDCnlHMIGtBgsqhkiG9w0BCRACCzGBnaCBmjCBkjELMAkGA1UEBhMCWkExFTAT BgNVBAgTDFdlc3Rlcm4gQ2FwZTESMBAGA1UEBxMJQ2FwZSBUb3duMQ8wDQYDVQQKEwZUaGF3 dGUxHTAbBgNVBAsTFENlcnRpZmljYXRlIFNlcnZpY2VzMSgwJgYDVQQDEx9QZXJzb25hbCBG cmVlbWFpbCBSU0EgMjAwMC44LjMwAgMKeUcwDQYJKoZIhvcNAQEBBQAEggEAWdFo0RZHu1If VOAFDP3OJ5SuKfa+zLUTiVtm03QSwobW2etA+mOir55ykHc+DAkQuz5rKEnioHctkq2H/pPl 8Aet4ZaXcYdlrIItQwdsmlsH2yyhruZMZjspjI4JZLSFDZD8NvruGLOciCuhFhqwg/3EmHUJ hHZN7K6YllILywp+lod2p1mFrcHFe8COsIv5lqp2ZnBv86LHEqYEYik6aWBnkWzepbr5CfDP 2bMcGTjz6QnEPY0lRgIH12Q8B7irPePD7gwaWu/EqYxdU8z4uLOaadFy5pOSRbArk3Kwarjw 9fz2GBds58stav+7nzZ4klo75SM2/wB/QJyjsv2oRgAAAAAAAA== --------------ms050103070102000008040302-- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/