Bug 112284
| Summary: | Possible typo in linux-2.4.22-ac1-scheduler-update.patch? | ||
|---|---|---|---|
| Product: | [Fedora] Fedora | Reporter: | Yue Shi Lai <ylai> |
| Component: | kernel | Assignee: | Arjan van de Ven <arjanv> |
| Status: | CLOSED NOTABUG | QA Contact: | Brian Brock <bbrock> |
| Severity: | medium | Docs Contact: | |
| Priority: | medium | ||
| Version: | 1 | ||
| Target Milestone: | --- | ||
| Target Release: | --- | ||
| Hardware: | All | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | Bug Fix | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2003-12-18 06:22:35 UTC | Type: | --- |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
This function has identical logic to that of 2.6.0-test11. Why do you think it's "contrary to the current kernel.org 2.6.0-test11 kernel"? OK, first sorry for the incorrect position of difference I gave. Now I looked through the patch files for 2.6.0-test6 (where this originates), and there seems to be a difference between patch-test5-O20.3int (http://ck.kolivas.org/patches/2.6/2.6.0-test5/patch-test5-O20.3int) from Con Kolivas and kernel.org's patch-2.6.0-test6. The issue is still strange, since O20.3int is the patch for O(1) interactivity, and there has been no comment except a "clean up" of CAN_MIGRATE_TASK. But since this seems not to be a Red Hat specific problem, maybe we can close this issue. Now I looked through the Kernel mailing list archives, the inversion of idle is obviously introduced by Andrew Theurer <habanero.com> (Wed Aug 27 2003). The way in 2.6.0-test6 and later, also Fedora Core 1, seems to be the correct one. I think we can close this issue. |
From Bugzilla Helper: User-Agent: Mozilla/5.0 (X11; U; Linux i686; de-AT; rv:1.4) Gecko/20030922 Description of problem: While possible effect is unknown, there is a possible typographical mistake in the Fedora Core's O(1) scheduler interactivity patch backport. The macro CAN_MIGRATE_TASK is modified by the Con Kolivas O(1) interactivity patch to static inline int can_migrate_task(task_t *, runqueue_t *, int, int). The first condition in the original macro (!idle || (NS_TO_JIFFIES(now - (p)->timestamp) > cache_decay_ticks)) has been negated (by using elementary Boolean algebra) to the first condition if (idle && (delta <= JIFFIES_TO_NS(cache_decay_ticks))) return 0; which returns 0 (false) if the condition is met. In linux-2.4.22-ac1-scheduler-update.patch from kernel-2.4.22-1.2115.nptl.src.rpm , and also contrary to the current kernel.org 2.6.0-test11 kernel, this condition has been rewritten to if (!idle && (delta <= JIFFIES_TO_NS(cache_decay_ticks))) return 0; (with negation of idle). Unless there is a good reason, the liklihood for this being a typographical mistake is very high. Version-Release number of selected component (if applicable): kernel-2.4.22-1.2115.nptl How reproducible: Always Steps to Reproduce: 1. Install (unpack) kernel-2.4.22-1.2115.nptl.src.rpm 2. Open linux-2.4.22-ac1-scheduler-update.patch and go to the patch section @@ -755,21 +1193,39 @@ for kernel/sched.c 3. Go to the third line in can_migrate_task() - and also note the previous macro variant cited above. Additional info: