Re: [libvirt] [PATCH] openvz: determine kb/pages only once

On 05/08/2012 02:12 PM, Guido Günther wrote: > to safe some syscalls (as suggested by Eric Blake) s/safe/save/ > --- > I've moved the code into an extra module since there's some more code to > come that should be shared between openvz_conf.c and openvz_driver.c > Cheers, > -- Guido > > src/Makefile.am | 3 ++- > src/openvz/openvz_conf.c | 12 ++++------- > src/openvz/openvz_driver.c | 19 +++++------------ > src/openvz/openvz_util.c | 51 ++++++++++++++++++++++++++++++++++++++++++++ > src/openvz/openvz_util.h | 28 ++++++++++++++++++++++++ > 5 files changed, 90 insertions(+), 23 deletions(-) > create mode 100644 src/openvz/openvz_util.c > create mode 100644 src/openvz/openvz_util.h This is quite a bit of churn for a micro-optimization, since it is not fixing any actual bugs. I'll review the code, but let's avoid applying it until after 0.9.12 is released. > +++ b/src/openvz/openvz_util.c > @@ -0,0 +1,51 @@ > +/* > + * openvz_driver.c: core driver methods for managing OpenVZ VEs > + * > + * Copyright (C) Guido Günther Year? > + static long kb_per_pages = 0; > + > + if (kb_per_pages == 0) { > + kb_per_pages = sysconf(_SC_PAGESIZE); > + if (kb_per_pages > 0) { > + kb_per_pages /= 1024; > + } else { > + openvzError(VIR_ERR_INTERNAL_ERROR, > + _("Can't determine page size")); > + kb_per_pages = 0; > + return -1; This says that in an error situation, every caller will repeat the sysconf() call and issue a new error. Seems reasonable. ACK with copyright nit fixed, post-release.