From mboxrd@z Thu Jan 1 00:00:00 1970 From: Leon Romanovsky Subject: Re: VERBOSE flags Date: Mon, 19 Sep 2016 16:25:18 +0300 Message-ID: <20160919132518.GH3273@leon.nu> References: <77cd1f09-fa39-6f75-6c01-c7ef18909f30@redhat.com> <0a26585a-2e54-1c24-d212-0e2469afb8d8@redhat.com> <20160919061558.GG3273@leon.nu> <1474288178.6520.12.camel@intel.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="WIIRZ1HQ6FgrlPgb" Return-path: Content-Disposition: inline In-Reply-To: <1474288178.6520.12.camel-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org> Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: "Dalessandro, Dennis" Cc: "dledford-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org" , "linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" List-Id: linux-rdma@vger.kernel.org --WIIRZ1HQ6FgrlPgb Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Sep 19, 2016 at 12:29:43PM +0000, Dalessandro, Dennis wrote: > On Mon, 2016-09-19 at 09:15 +0300, Leon Romanovsky wrote: > > The function pointers will cause us to create two similar functions > > (debug/regular) for every important function. It will leave to code > > duplication and/or introducing of new code to fill additional fields > > in returns to debug functions, so they will be able to print it. > > I do sort of like Doug's idea. It means you can easily instrument the > heck out of a routine and have it always available. It provides more > flexibility in what you can do in a debug version. > > You do make a valid point though about duplicating code. Perhaps that > can be alleviated to some extent just by refactoring and adding > inlines, etc. =A0 At the end, we will invent tracepoints :) > > > I wanted to propose to use tracepoints to provide debug information > > in > > data paths. The tracepoints infrastructure uses hooks in the code > > with > > minimal impact on performance. > > This is so far the path we have chosen for hfi1. We have a number of > tracepoints in various parts of the code. Again it's available on > demand without special kernels or boot/driver options.=A0 CONFIG_SDMA_VERBOSITY ???? > > > > Then we can drop the CONFIG_*_DEBUG options out of all of the > > > drivers.=A0=A0That would be my preference.=A0=A0I don't want any comp= ile > > > time > > > options because you never will be running a debug kernel when you > > > need > > > it.=A0=A0Per device, run time selectable so that you get 0 overhead in > > > the > > > normal case is what I would like to see. > > > > Great, > > We are aligned on this point, so do I. I see no reason in special > > compiled > > kernel or global module parameter to print debug prints for whole > > driver. > > Same here. > > -Denny --WIIRZ1HQ6FgrlPgb Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBAgAGBQJX3+c+AAoJEORje4g2clinQEoQAId0jLZNwxR9eUyPseaiMwg7 5X+gnoBCtUWE+2z8adQIp2fLuTt8/jg0oUW6sgA+en5OuFNpFEzmEkFUnI7e3D0u cV8+bDkWG930kZxTopjkoym2okNF4nmi2HLLKVHXoDwZ6FxOZ+6CdbXgmrMuTQAV cgZ28LCPw7NcINthamylgb3nZ86nv9lqakeB6T8X96nAMfssow1N4vcQbpUIXM23 m5sKJQNGJL90KY5JvQxBYerwALgc3187JguaMNb1bsh8X490/QAW+xbCoYDZHAcs f2qnHnwhRbXz3Kgx/czLOuY+x6JMVFK8KrOgZHkKMGvIDCLjeyEjAkZlCRv6sddA WPX/Z5C3Wzj6dthjChxRIlquiZjadqhspcBV82nPqHEe2vhFvX87KLxaZJCk2JjJ pcIQoUq0KINa8P1q/+ksV4bVUGTiaMRIz0BOmb4ywZYtXe2PDMvS4yI9FJROzAAH R6JY1iFSuxZKIxDI1cQavUu54puTMkmohX2/DesRgLNL/qXqbSxMUR2wgDCws9/4 f4zvDfPUIytjqPBkbScxXBPkUnprQB6te/6gLMq/IcyL0S9gGWnRfrWQgkU1YZC4 WQVC6vWe3OAmwSpoKn3trGDAPWW022eQBAa3o4P97RlvwW/0cq7GRWOiSqN1ypew N2RSi8NE79kb8qpfw3mW =TdyJ -----END PGP SIGNATURE----- --WIIRZ1HQ6FgrlPgb-- -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html