Date: Mon, 30 Aug 1999 15:34:17 +0300 (EEST) From: Vsevolod Lobko <seva@sevasoft.alex-ua.com> To: FreeBSD-gnats-submit@freebsd.org Subject: i386/13468: [PATCH] Low ATAPI performance with block devices (sys/i386/isa/atapi.c) Message-ID: <199908301234.PAA60807@sevasoft.alex-ua.com>
next in thread | raw e-mail | index | archive | help
>Number: 13468
>Category: i386
>Synopsis: [PATCH] incorrect wakeup argument in atapi_free()
>Confidential: no
>Severity: non-critical
>Priority: medium
>Responsible: freebsd-bugs
>State: open
>Quarter:
>Keywords:
>Date-Required:
>Class: sw-bug
>Submitter-Id: current-users
>Arrival-Date: Mon Aug 30 05:40:01 PDT 1999
>Closed-Date:
>Last-Modified:
>Originator: Vsevolod Lobko
>Release: FreeBSD 4.0-CURRENT i386
>Organization:
None
>Environment:
FreeBSD sevasoft.alex-ua.com 4.0-CURRENT FreeBSD 4.0-CURRENT #35: Wed Aug 25 21:24:34 EEST 1999 root@sevasoft.alex-ua.com:/usr/src/sys/compile/SEVASOFT i386
>Description:
When using block devices system places many concurent commands for device
ATAPI driver have static buffer for 16 commands, and after 16 commands,
atapi_alloc tsleep's on ata structure
atapi_free have wakeup, but with incorrect sleep addr &ata
>How-To-Repeat:
dd if=/dev/zero of=/dev/rwfd0 bs=2k count=100
and
dd if=/dev/zero of=/dev/wfd0 bs=2k count=100
have very different transfer rates
>Fix:
Apply patch:
Index: atapi.c
===================================================================
RCS file: /home/free_rep/src/sys/i386/isa/atapi.c,v
retrieving revision 1.34
diff -u -r1.34 atapi.c
--- atapi.c 1999/04/19 18:44:16 1.34
+++ atapi.c 1999/08/30 12:22:41
@@ -507,11 +507,10 @@
static void atapi_free (struct atapi *ata, struct atapicmd *ac)
{
- if (! ata->free)
- wakeup ((caddr_t)&ata);
ac->busy = 0;
ac->next = ata->free;
ata->free = ac;
+ wakeup ((caddr_t)ata);
}
/*
>Release-Note:
>Audit-Trail:
>Unformatted:
To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-bugs" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199908301234.PAA60807>