BLK_STOP_QUEUE(9) Block Devices BLK_STOP_QUEUE(9)NAME
blk_stop_queue - stop a queue
SYNOPSIS
void blk_stop_queue(struct request_queue * q);
ARGUMENTS
q
The struct request_queue in question
DESCRIPTION
The Linux block layer assumes that a block driver will consume all entries on the request queue when the request_fn strategy is called.
Often this will not happen, because of hardware limitations (queue depth settings). If a device driver gets a 'queue full' response, or if
it simply chooses not to queue more I/O at one point, it can call this function to prevent the request_fn from being called until the
driver has signalled it's ready to go again. This happens by calling blk_start_queue to restart queue operations. Queue lock must be held.
COPYRIGHT Kernel Hackers Manual 3.10 June 2014 BLK_STOP_QUEUE(9)
Check Out this Related Man Page
queue(9S) Data Structures for Drivers queue(9S)NAME
queue - STREAMS queue structure
SYNOPSIS
#include <sys/stream.h>
INTERFACE LEVEL
Architecture independent level 1 (DDI/DKI)
DESCRIPTION
A STREAMS driver or module consists of two queue structures, one for upstream processing (read) and one for downstream processing
(write). This structure is the major building block of a stream. It contains pointers to the processing procedures, pointers to the next
and previous queues in the stream, flow control parameters, and a pointer defining the position of its messages on the STREAMS scheduler
list.
The queue structure is defined as type queue_t.
STRUCTURE MEMBERS
struct qinit*q_qinfo; /* module or driver entry points */
struct msgb*q_first; /* first message in queue */
struct msgb*q_last; /* last message in queue */
struct queue*q_next; /* next queue in stream */
struct queue*q_link; /* to next queue for scheduling*/
void *q_ptr; /* pointer to private data structure */
size_t q_count; /* approximate size of message queue */
uint_t q_flag; /* status of queue */
ssize_t q_minpsz; /* smallest packet accepted by QUEUE*/
ssize_t q_maxpsz; /*largest packet accepted by QUEUE */
size_t q_hiwat; /* high water mark */
size_t q_lowat; /* low water mark */
Valid flags are as follows:
QENAB Queue is already enabled to run.
QWANTR Someone wants to read queue.
QWANTW Someone wants to write to queue.
QFULL Queue is considered full.
QREADR This is the reader (first) queue.
QUSE This queue is in use (allocation).
QNOENB Do not enable queue by way of putq().
SEE ALSO strqget(9F), strqset(9F), module_info(9S), msgb(9S), qinit(9S), streamtab(9S)
Writing Device Drivers
STREAMS Programming Guide
SunOS 5.10 12 Nov 1996 queue(9S)
Hi everyone,
I know the following questions are noobish questions but I am asking them because I am confused about the basics of history behind UNIX and LINUX.
Ok onto business, my questions are-:
Was/Is UNIX ever an open source operating system ?
If UNIX was... (21 Replies)
Hello and thanks in advance for any help anyone can offer me
I'm trying to learn the find command and thought I was understanding it... Apparently I was wrong. I was doing compound searches and I started getting weird results with the -size test. I was trying to do a search on a 1G file owned by... (14 Replies)
hi all,
i have installed quota on my centos 7 machine and its what im after (setting size limit on users, so they cant fill the hard drive)
i want to now make this part of my create user script for my sftp server so i want to do a echo and a read command so i capture the limit they enter... (0 Replies)
Hi everybody,
Which Unix base OS have best performance for HOST virtualization?
I tested SmartOS but it needs another OS to connect remotely!
Thanks in advance. (11 Replies)
Hi All,
I need to write a shell script which opens a file and increments the version(text) within the file every time the script runs. For example:
$ cat docker_file.yml
version: '3.1'
services:
ui:
image: repo-srv.dev.io:5000/facebook/ui:0.0.2-QA1
$
So, I would like... (6 Replies)
Dear Team
We use DB2 v10.5 and using DBArtisan tool
Can someone please guide how to convert digits to binary numbers using db2 feature.
Ex> for number 9 , binary should be 1001 ( 8+1)
Any help appreciated. Thanks (2 Replies)
hi folks,
how to using tar with exclude directory and compress it using tar.Z
i only know how to exclude dir only with this command below:
tar -cvf /varios/restore/test.tar -X excludefile.txt /jfma/test1/
how to compress it using 1 command?
Thanx
Please use CODE tags as... (6 Replies)
Quite an obscure question I think.
We have a rebuild process for remote sites that allows us to PXE rebuild a till (actually a PC with a touch screen and various fancy bits) running CentOS. The current CentOS5 tills work just fine with a tar image restore and some personalisation. Sadly,... (4 Replies)
Hello All,
I had recently learnt a bit of Docker(which provides containerization process).
Here are some of my learning points from it.
Let us start first with very basic question:
What is Docker:
Docker is a platform for sysadmins and developers to DEPLOY, DEVELOP and RUN applications ... (7 Replies)
What is the point of this? Whenever I close my shell it appends to the history file without adding this. I have never seen it overwrite my history file.
# When the shell exits, append to the history file instead of overwriting it
shopt -s histappend (3 Replies)
Hello... And thanks in advance for any help anyone can offer me
I was trying to work out the differences between displaying modify, access, and change times with the 'ls' command. Everything seems in order when I look at files, but the access time on a directory doesn't seem to change when I... (4 Replies)
Hello everyone,
I am having an issue here with CentOS release 6.6 (Final) that shows all of the space used up, but I can't tell where the space went.
Seemingly I am using up 100%, according to
df -h
Filesystem Size Used Avail Use% Mounted on... (27 Replies)
I'm trying to use a bash script for a psych experiment that involves listening to sound files and responding. If I have something like the code below, how can I make sure that a key press is assigned to RESPONSE only after the second echo statement?
for i in 1 2 3; do
echo "Ready?"
sleep 2
... (10 Replies)
After the success of the jq - tool for parsing and manipulating JSON-Data someone wrote a tool called yq, which aims to be the same for YAML, what jq is for JSON. Seems to work fine. I'll definitely give it a chance in future.
Example YAML-File:
--- !ruby/object:Puppet::Node::Facts
... (1 Reply)
Dear All,
I am very pleased to announce that Dave Munro (gull04) is joining the Moderation Team, after being a very valuable member of UNIX.com for 15+ years.
Dave is an IT Consultant with 30 years of experience this year, has worked in many of the industry vertical market segments and has... (6 Replies)