| Message ID | 20170301172219.9683-1-mwilck@suse.com (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Delegated to: | Mike Snitzer |
| Headers | show |
Applied. Thanks. On Wed, Mar 1, 2017 at 6:22 PM, Martin Wilck <mwilck@suse.com> wrote: > This uses roughly 10% cycles of the sscanf-based implementation. > > Improves: ee8888f0 "multipath-tools: improve processing efficiency..." > Signed-off-by: Martin Wilck <mwilck@suse.com> > --- > libmultipath/uevent.c | 37 +++++++++++++++++++++++-------------- > 1 file changed, 23 insertions(+), 14 deletions(-) > > diff --git a/libmultipath/uevent.c b/libmultipath/uevent.c > index 6e2527bd..367e129a 100644 > --- a/libmultipath/uevent.c > +++ b/libmultipath/uevent.c > @@ -143,26 +143,35 @@ uevent_need_merge(void) > return need_merge; > } > > +static bool > +uevent_can_discard_by_devpath(const char *devpath) > +{ > + static const char BLOCK[] = "/block/"; > + const char *tmp = strstr(devpath, BLOCK); > + > + if (tmp == NULL) { > + condlog(4, "no /block/ in '%s'", devpath); > + return true; > + } > + tmp += sizeof(BLOCK) - 1; > + if (*tmp == '\0') > + /* just ".../block/" - discard */ > + return true; > + /* > + * If there are more path elements after ".../block/xyz", > + * it's a partition - discard it; but don't discard > ".../block/sda/". > + */ > + tmp = strchr(tmp, '/'); > + return tmp != NULL && *(tmp + 1) != '\0'; > +} > + > bool > uevent_can_discard(struct uevent *uev) > { > - char *tmp; > - char a[11], b[11]; > struct config * conf; > > - /* > - * keep only block devices, discard partitions > - */ > - tmp = strstr(uev->devpath, "/block/"); > - if (tmp == NULL){ > - condlog(4, "no /block/ in '%s'", uev->devpath); > + if (uevent_can_discard_by_devpath(uev->devpath)) > return true; > - } > - if (sscanf(tmp, "/block/%10s", a) != 1 || > - sscanf(tmp, "/block/%10[^/]/%10s", a, b) == 2) { > - condlog(4, "discard event on %s", uev->devpath); > - return true; > - } > > /* > * do not filter dm devices by devnode > -- > 2.12.0 > > -- > dm-devel mailing list > dm-devel@redhat.com > https://www.redhat.com/mailman/listinfo/dm-devel > -- dm-devel mailing list dm-devel@redhat.com https://www.redhat.com/mailman/listinfo/dm-devel
diff --git a/libmultipath/uevent.c b/libmultipath/uevent.c index 6e2527bd..367e129a 100644 --- a/libmultipath/uevent.c +++ b/libmultipath/uevent.c @@ -143,26 +143,35 @@ uevent_need_merge(void) return need_merge; } +static bool +uevent_can_discard_by_devpath(const char *devpath) +{ + static const char BLOCK[] = "/block/"; + const char *tmp = strstr(devpath, BLOCK); + + if (tmp == NULL) { + condlog(4, "no /block/ in '%s'", devpath); + return true; + } + tmp += sizeof(BLOCK) - 1; + if (*tmp == '\0') + /* just ".../block/" - discard */ + return true; + /* + * If there are more path elements after ".../block/xyz", + * it's a partition - discard it; but don't discard ".../block/sda/". + */ + tmp = strchr(tmp, '/'); + return tmp != NULL && *(tmp + 1) != '\0'; +} + bool uevent_can_discard(struct uevent *uev) { - char *tmp; - char a[11], b[11]; struct config * conf; - /* - * keep only block devices, discard partitions - */ - tmp = strstr(uev->devpath, "/block/"); - if (tmp == NULL){ - condlog(4, "no /block/ in '%s'", uev->devpath); + if (uevent_can_discard_by_devpath(uev->devpath)) return true; - } - if (sscanf(tmp, "/block/%10s", a) != 1 || - sscanf(tmp, "/block/%10[^/]/%10s", a, b) == 2) { - condlog(4, "discard event on %s", uev->devpath); - return true; - } /* * do not filter dm devices by devnode
This uses roughly 10% cycles of the sscanf-based implementation. Improves: ee8888f0 "multipath-tools: improve processing efficiency..." Signed-off-by: Martin Wilck <mwilck@suse.com> --- libmultipath/uevent.c | 37 +++++++++++++++++++++++-------------- 1 file changed, 23 insertions(+), 14 deletions(-)