Massive "Found bio_cmd = 0x5" with options CAM_IOSCHED_DYNAMIC
Date: Thu, 05 May 2022 00:03:16 UTC
Hi.
After updating src main git: f44280bf5fbb to git: 1599fc904d35,
with options CAM_IOSCHED_DYNAMIC on kernel config file,
A plenty of "Found bio_cmd = 0x5" appear on console and dmesg.
With quick look under src/sys/, bio_cmd = 0x5 means BIO_FLUSH,
and the printf() only appears on src/sys/cam/cam_iosched.c line 1621.[1]
Maybe it actually wouldn't be harmful (just annoying), but possibly
any conditions blocking BIO_FLUSH to reach there would be lost.
(The printf() itself was already there at git: f44280bf5fbb.)
If it's actualy not at all harmful, and BIO_FLUSH case is coming
through here is intentional change, is it really needed to be printed?
There were 4 commits to cam_iosched.c within the span.
cc1572ddeb8cd82879ce0cca634bf6a8830c0f40 [2]
cam iosched: Remove write bias when read bias = 0
b65803ba5773d5fb37fa2403105db199569a5811 [3]
cam iosched: default to no read bias in dynamic ioscheduling
d592c0db8ba773c143eeea28610288f800fa651a [4]
cam: add hw.cam.iosched.read_bias
1599fc904d35cfa8eecad92818d1f4b55de6818f [5]
iosched: Move bio_next() inside of the CAM_IOSCHED_DYNAMIC ifdef
[1] https://cgit.freebsd.org/src/tree/sys/cam/cam_iosched.c#n1621
[2]
https://cgit.freebsd.org/src/commit/?id=cc1572ddeb8cd82879ce0cca634bf6a8830c0f40
[3]
https://cgit.freebsd.org/src/commit/?id=b65803ba5773d5fb37fa2403105db199569a5811
[4]
https://cgit.freebsd.org/src/commit/?id=d592c0db8ba773c143eeea28610288f800fa651a
[5]
https://cgit.freebsd.org/src/commit/?id=1599fc904d35cfa8eecad92818d1f4b55de6818f
Regards.
--
Tomoaki AOKI <junchoon@dec.sakura.ne.jp>