freebsd-hackers@freebsd.org
Hello, What is effectively the difference between PICKUP/DROP_GIANT and mtx_lock/unlock(&Giant) ? From the macro expansion, i surmise that PICKUP/DROP_GIANT deals with recursion in Giant locking.Is this correct ? is this the only difference ? What will happen if i mix the usage of PICKUP/DROP_GIANT and mtx_lock/unlock(&Giant) ? Also,is there any hard and fast rule prescribing which method of taking the Giant should be used where in the kernel ? TIA. Regards, Pranav --- To argue with a person who has renounced the use of reason is like administering medicine to the dead. -- Thomas Paine ___ freebsd-hackers@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-hackers To unsubscribe, send any mail to "[EMAIL PROTECTED]"
freebsd-hackers@freebsd.org
On Sun, Mar 12, 2006 at 04:25:07PM +0530, Pranav Peshwe wrote: > Hello, > What is effectively the difference between PICKUP/DROP_GIANT and > mtx_lock/unlock(&Giant) ? From the macro expansion, i surmise that > PICKUP/DROP_GIANT deals with recursion in Giant locking.Is this correct ? is > this the only difference ? What will happen if i mix the usage of > PICKUP/DROP_GIANT and mtx_lock/unlock(&Giant) ? You can't mix them, because they are used in different situtation. You call DROP_GIANT and later PICKUP to handle situations where it is required to drop GIANT for a while. You call mtx_lock and later unlock to hold GIANT for a while. -- B.Walterhttp://www.bwct.de http://www.fizon.de [EMAIL PROTECTED] [EMAIL PROTECTED][EMAIL PROTECTED] ___ freebsd-hackers@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-hackers To unsubscribe, send any mail to "[EMAIL PROTECTED]"
freebsd-hackers@freebsd.org
Date: Sun, 12 Mar 2006 16:25:07 +0530 > From: "Pranav Peshwe" <[EMAIL PROTECTED]> > Subject: Doubts about PICKUP_GIANT() and mtx_lock(&Giant). > To: freebsd-hackers@freebsd.org > Message-ID: > <[EMAIL PROTECTED]> > Content-Type: text/plain; charset=ISO-8859-1 > > Hello, > What is effectively the difference between PICKUP/DROP_GIANT and > mtx_lock/unlock(&Giant) ? From the macro expansion, i surmise that > PICKUP/DROP_GIANT deals with recursion in Giant locking.Is this correct ? > is > this the only difference ? What will happen if i mix the usage of > PICKUP/DROP_GIANT and mtx_lock/unlock(&Giant) ? > Also,is there any hard and fast rule prescribing which method of taking > the > Giant should be used where in the kernel ? > > TIA. > > Regards, > Pranav > > > --- > To argue with a person who has renounced the use of reason is like > administering medicine to the dead. -- Thomas Paine > >In my opinion,DROP_GIANT() guarantees that Giant is *really* dropped even it is recursively held.Sometimes we have to make sure that Giant is not held,and mtx_unlock(&Giant) can't give us such a promise,so you shouldn't use it in such situations. Mix the usage of DROP_GIANT() and mtx_unlock(&Giant) is not a good idea,I think. In fact,if you really do it,even the compiler will reject your source code :-). Regards, MingyanGuo -- Three passions, simple but overwhelmingly strong, have governed my life: the longing for love, the search for knowledge, and unbearable pity for the suffering of mankind. -Bertrand Russell ___ freebsd-hackers@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-hackers To unsubscribe, send any mail to "[EMAIL PROTECTED]"
Re: About amd64 dualcore problems with two SATA disks and nforce4
Hi, Well... Hopeful with your mailings, I updated the kernel (cvsup) and rebuilt it... the problem's still there... detects one SATA disk (ad4) and crashes before acknowledging the second (ad6)... - Daniel S�ren Schmidt <[EMAIL PROTECTED]> wrote: Daniel Valencia wrote: > Hi, > > So, what's your last src/ cvsup date/time? is your machine dualcore? if > so, are you building using the SMP option? yep: CPU: AMD Athlon(tm) 64 X2 Dual Core Processor 4800+ (2412.37-MHz K8-class CPU) and yep: FreeBSD/SMP: Multiprocessor System Detected: 2 CPUs cpu0 (BSP): APIC ID: 0 cpu1 (AP): APIC ID: 1 > mine breaks when in SMP mode... in GENERIC it works, just it doesn't > detect the second SATA disk Well, no problems here with that, the nve interface is something else though :) -S�ren > - Daniel > > > */S�ren Schmidt /* wrote: > > Daniel Valencia wrote: > > Hello, > > > > I started a short thread a few weeks ago, pointing out a problem > with my dualcore athlon64, when detecting the second SATA disk > (/dev/ad6)... my chipset is an nForce4... The problem was narrowed > down to a few commits performed at a particular date and time. My > questions are: is it safe to update my kernel now? have those > problems been fixed? is there something I can do to help (like > testing or so)? > > > For whatever its worth my NF4 board finds all 4 SATA disks perfectly > both in i386 and amd64 mode: > > atapci0: port > 0x1f0-0x1f7,0x3f6,0x170-0x177,0x376,0xe000-0xe00f at device 6.0 on pci0 > ata0: on atapci0 > ata1: on atapci0 > atapci1: port > 0x9f0-0x9f7,0xbf0-0xbf3,0x970-0x977,0xb70-0xb73,0xcc00-0xcc0f mem > 0xfe02b000-0xfe02bfff irq 21 at device 7.0 on pci0 > ata2: on atapci1 > ata3: on atapci1 > atapci2: port > 0x9e0-0x9e7,0xbe0-0xbe3,0x960-0x967,0xb60-0xb63,0xb800-0xb80f mem > 0xfe02a000-0xfe02afff irq 22 at device 8.0 on pci0 > ata4: on atapci2 > ata5: on atapci2 > ad0: 38166MB at ata0-master UDMA100 > ad1: 78533MB at ata2-master SATA300 > ad2: 78533MB at ata3-master SATA300 > ad3: 70911MB at ata4-master SATA150 > ad4: 70911MB at ata5-master SATA150 > atausb0: > addr 2> on uhub1 > atausb0: using SCSI over Bulk-Only > ata6: on atausb0 > acd0: CDRW at ata6-master USB2 > Trying to mount root from ufs:/dev/ad0s1a > > -S�ren > > > > Yahoo! Mail > Bring photos to life! New PhotoMail > > makes sharing a breeze. ___ freebsd-hackers@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-hackers To unsubscribe, send any mail to "[EMAIL PROTECTED]" - Yahoo! Mail Bring photos to life! New PhotoMail makes sharing a breeze. ___ freebsd-hackers@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-hackers To unsubscribe, send any mail to "[EMAIL PROTECTED]"
