gmane.linux.kernel.kernelnewbies

Re: FYI: sched summary - new version

Sandeep K Sinha — 2008-12-03T18:48:58

Thanks Hendrik. Really Good ! On Wed, Dec 3, 2008 at 11:58 PM, rahul p gmail.com> wrote:

Re: FYI: sched summary - new version

rahul p — 2008-12-03T18:28:47

Thanks Henrik. That's valuable. I'll go through it sometime this week. - Rahul On 12/3/08, Henrik Austad stud.ntnu.no> wrote:

Re: FYI: sched summary - new version

Henrik Austad — 2008-12-03T13:16:16

So I've updated to v0.5, which contains a bit more about CFS, spelling fixes and a couple of new figures. Thanks to all for the feedback I've received lately! :-)

error when rmmod g_file_storage module

snoppy1314 — 2008-12-03T13:10:25

Hi, eveyone: 1. These days I'm trying to make my 2440 board(its CPU is s3c2440) to be notified as a disk of PC when connecting a usb line. Now nearly everyone is ok.but when I want to rmmod the g_file_storage module,error happened. #rmmod g_file_storage After I execute the last command, the board is dead, and a few minutes later, the information below is showed: INFO: task rmmod:850 blocked for more than 120 seconds. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. rmmod D c01f7284 0 850 807 [] (__sched_text_start+0x0/0x2c0) from [] (schedule_timeout+0x24/0xbc) [] (schedule_timeout+0x0/0xbc) from [] (wait_for_common+0x124/0x1bc) r8:00000880 r7:00000002 r6:c1c8013c r5:7fffffff r4:c1fe5edc [] (wait_for_common+0x0/0x1bc) from [] (wait_for_completion+0x18/0x1c) r7:c1fe5f48 r6:c1fe4000 r5:00000000 r4:c1c800a0 [] (wait_for_completion+0x0/0x1c) from [] (fsg_cleanup+0x44/0x68 [g_file_storage

Re: Network monitor tool

Erik Mouw — 2008-12-03T12:32:50

On Wed, 3 Dec 2008 13:57:00 +0530 "mayur nande" gmail.com> wrote: Wireshark is a protocol analyser. To actually monitor systems you need something like Nagios. Erik PS to OP: network monitoring is not kernel related so off topic on this list.

Re: boot Linux from Linux

Matthias Kaehlcke — 2008-12-03T11:13:20

El Tue, Dec 02, 2008 at 06:25:55PM -0800 Bizhan Gholikhamseh (bgholikh) ha dit: not sure what you are looking for, maybe http://www.coreboot.org/ could be interesting for you

Re: boot Linux from Linux

dinesh bansal — 2008-12-03T10:47:10

On Wed, Dec 3, 2008 at 7:55 AM, Bizhan Gholikhamseh (bgholikh) < bgholikh< at >cisco.com> wrote: Do you mean running Linux as application on-the-top of existing Linux Operating System? Then you should take a look at virtualization.

Re: Network monitor tool

mayur nande — 2008-12-03T08:27:00

Hi Shyam, You can go for Wireshark (formerly) ethereal: http://sourceforge.net/projects/wireshark/ Regards Mayur Nande On Wed, Dec 3, 2008 at 1:04 PM, Shyam Burkule gmail.com>wrote:

Re: question about __virt_to_phys and __phys_to_virt

mahaveer darade — 2008-12-03T05:22:19

these are used in context of dma mapping. go through documentation/dma-mapping.txt for more information. On Wed, Dec 3, 2008 at 9:11 AM, loody gmail.com> wrote: cz they are directly mapped.

Re: boot Linux from Linux

Kalpesh Rathod — 2008-12-03T05:21:07

Bizhan, Have a look at 'kexec' . It may not meet 100% your requirement but comes close. Thanks, Kalpesh On Wed, Dec 3, 2008 at 9:30 AM, Mark Brown marksmachinations.com>wrote:

Re: boot Linux from Linux

Mark Brown — 2008-12-03T04:00:27

Bizhan, Yes it is do-able you can actually use the zImage header to bootstrap the kernel. You can modify linux/arch//boot/compressed/ head.S and add the boot loader logic there. Then you need to place your zImage in the location your platform normally loads the boot loader. You should really spend the time and write a mini-boot loader it is not any harder than doing what I mentioned above. Regards,

question about __virt_to_phys and __phys_to_virt

loody — 2008-12-03T03:41:56

Dear all: If I remember correctly, the translation between virtual and physical memory should use page table. But in include/asm/memory.h, these 2 functions seem don't use page table to do the translation. #define __virt_to_phys(x)((x) - PAGE_OFFSET + PHYS_OFFSET) #define __phys_to_virt(x)((x) - PHYS_OFFSET + PAGE_OFFSET) where in mmu mode #define PHYS_OFFSETUL(0x00000000) #ifndef PAGE_OFFSET #define PAGE_OFFSETUL(0xc0000000) #endif not in mmu mode #ifndef PHYS_OFFSET #define PHYS_OFFSET (CONFIG_DRAM_BASE) #endif #ifndef PAGE_OFFSET #define PAGE_OFFSET(PHYS_OFFSET) #endif Why they don't need page table to do the page table translation? Except the caller is at the first page and in kernel, the first page is located at the first frame. thanks for your help, miloody -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis< at >nl.linux.org Please read the FAQ at http://kernelnewbies.org/FAQ

boot Linux from Linux

Bizhan Gholikhamseh (bgholikh — 2008-12-03T02:25:55

Hi all, Is there any way to use Linux as bootloader to boot Linux? It might sound crazy but I need to figure out this. Many thanks in advance, Bizhan

IRQ IN LINUX

pl ice — 2008-12-02T16:58:04

hi, when i study interrupt handle in linux,i confuse a question about PIC(8259) and APIC now we have both in our hardware ,and how the kernel know if the hardware support APIC ,only through our configuration about enable APIC ? And if we configure APIC in kernel configuration ,will kernel init PIC in hardware,APIC and PIC only one work or both work? Best Regards, Lin

tty driver read implementation

Denis Borisevich — 2008-12-02T15:54:42

Hi everbody! Could anybody explain to me how the read() is implemented in tty drivers? I mean what functions should I register in my driver to complete read() system call successfully? Thanks in advance. -- Denis -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis< at >nl.linux.org Please read the FAQ at http://kernelnewbies.org/FAQ

Japan + Korea Linux Symposium

Peter Teoh — 2008-12-02T06:11:41

The Linux Foundation Japan Symposium: http://jp.linuxfoundation.org/?q=node/18 And this: Korea Technical Jamboree: http://tree.celinuxforum.org/CelfPubWiki/KoreaTechJamboree4

learn c in 21 days

saravanampatty tp — 2008-12-02T05:16:28

Learn c in 21 days EXECUTIVE OFFICER SARAVANAMPATTY TOWN PANCHAYAT COIMBATORE - 35. Add more friends to your messenger and enjoy! Go to http://messenger.yahoo.com/invite/

Re: Locks and the FSB

Elad Lahav — 2008-12-01T22:00:47

I'm wondering if the high event counts following spin_unlock_irqrestore() are due to an OProfile quirk. OProfile depends on interrupts, which are disabled inside the critical section protected by the spin lock. It may end up accounting for all events that occurred inside the critical section immediately after the processor exits this section. --Elad -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis< at >nl.linux.org Please read the FAQ at http://kernelnewbies.org/FAQ

Re: Locks and the FSB

Elad Lahav — 2008-12-01T15:50:10

Sorry for the late response. Not in this case. I have 4 web server processes running, each pinned to a different CPU. The interrupts are also pinned, such that interrupts for a specific NIC occur only on the CPU handling the data relevant to that web server process. Yes, this may be a case of false sharing, I'll check that. Here are the top functions with respect to global_power_events in the 3 processor case: samples % samples % samples % samples % app name symbol name 141924 9.3228 182254 11.5263 178498 11.2869 621626 38.7608 vmlinux cpu_idle 138963 9.1283 175842 11.1208 172319 10.8962 588353 36.6861 vmlinux poll_idle 79616 5.2299 103271 6.5312 101016 6.3875 338251 21.0913 vmlinux __rcu_process_callbacks 43093 2.8307 42444 2.6843 42888 2.7119 0 0 e1000.ko e1000_xmit_frame 42270 2.7767 42223 2.6703 43035 2.7212 0 0 vmlinux

Re: GCC 4.4 hacks in the Linux kernel

Frédéric Weisbecker — 2008-12-01T14:02:02

2008/12/1 Peter Teoh gmail.com>: Thanks! Very interesting :-) -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis< at >nl.linux.org Please read the FAQ at http://kernelnewbies.org/FAQ

Re: question on priority imbalance in Linux SMP scheduler!

Henrik Austad — 2008-12-01T12:54:14

Hello Note, this article is rather outdated as it describes the O(1) scheduler, and not the new CFS (which was introduced in 2.6.23) One of the major differences, is that normal tasks, i.e. tasks with priority between 139 and 100, are handled by CFS (SCHED_NORMAL, SCHED_BATCH and SCHED_IDLE). pri 99 to 1 (or 0, if you count in the top-priority real-time kernel priority not accessible from user-space), is handled by SCHED_RR/SCHED_FIFO. Each CPU has its own runqueue (struct rq), which have a pointer to the real-time runqueue and to cfs_rq, the red-black tree containing all normal tasks. The run-queue for real-time tasks is very similar to the old O(1) scheduler, except that it has 100 slots instead of 140, and consist of only one queue, not 2 (active and expired) as O(1). does anyone know how the old O(1) handled real-time tasks wrt to the 2 queues and active/expired swapping? Well, for a starter, to balance tasks perfectly on n processors, is NP-hard. This is due to the bin-pac