| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Date: Wed, 4 May 2011 14:11:34 +0200 From: "Eibach, Dirk" <Eibach@...ys.de> To: <linux-kernel@...r.kernel.org> Subject: msleep() an load average LDD Chapter 7 says "In general, if you can tolerate longer delays than requested, you should use schedule_timeout, msleep or ssleep.". Following this rule, my kernel thread does: while(1) msleep(1000); Seconds later userspace guys start whining: "Your driver is evil, loadavg is 1 and we did not even start our fancy application". I say: "No, my code is perfectly fine, I followed LDD to the letter." So the userspace guys head back to their cave, only to return after 5 hours of googling: "Hey, we know what you are doing. Your kernel thread does uninterruptible sleeps. Wikipedia says, this means you are probably waiting for disk activity." Since I don't like having those whining userspace guys around I change my code, reluctantly: while(1) msleep_interruptible(1000); Seconds later they say: "All hail great kernel hacker! You fixed it in no time." I appreciate their admiration, but still there are doubts in my mind: Is this code really any better? Is the loadavg metric broken beyond repair? Should I really avoid msleep, just to stop those userspace guys from whining? The truth must be out there ... Cheers Dirk -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists