XRP Ninja

Update: as reported by Fai Wong, -O1 is actually fine. Obviously, it must be some flag(s) which is(are) enabled at -O2 but not at -O1 caused this problem. However, it is not a priority ATM. Anyone who is interested in it is welcome to investigate it further. As I have mentioned earlier , sqlite compiled with -O2 may cause xulrunner to segfault in N32 userland on Loongson. Well, I almost forget it. So to remove the -O2 from CFLAGS once and for all, I adopted the technique described here . zhangle@2f env $ pwd /etc/portage/env zhangle@2f env $ find . ./dev-db ./dev-db/sqlite ./O2-removal zhangle@2f env $ cat O2-removal pre_pkg_setup() { elog "bashrc is removing \"-O2\" from CFLAGS for $PN" CFLAGS="${CFLAGS/-O2/}" } zhangle@2f env $ ls -l dev-db/sqlite lrwxrwxrwx 1 zhangle zhangle 13 2009-08-01 16:10 dev-db/sqlite -> ../O2-removal

I just found that, it is actually very easy to trigger the problem that the -mfix-ls2f-kernel as option could fix. Like just emerging glibc could hang the system. So if you are using linux-loongson/2.6.30/stable branch from this git tree http://dev.lemote.com/git?p=rt4ls.git;a=summary, you maybe want to line 129 of arch/mips/Makefile: $(call cc-option,-march=loongson2f,-march=r4600) $(call cc-optoin,-mtune=loongson2f) to $(call cc-option,-march=loongson2f,-march=r4600) $(call as-option,-Wa$(comma)-mfix-ls2f-kernel,) Actually, $(call cc-optoin,-mtune=loongson2f) here is not required. BTW, glibc-2.10.1 is ready in my overlay. This version could solve the gdb issue: Error while reading shared library symbols: find_new_threads_callback: cannot get thread info: generic error find_new_threads_callback: cannot get thread info: generic error This happened previously when debugging multithread applications.

I have not blogged here for some time. But that does not necessarily mean I am slacking, ;). Instead I have been doing things. I should've blogged more. http://www.gentoo-cn.org/gitweb/?p=loongson.git;a=shortlog Redhatter posted two blogs related to Yeeloong's status. I guess I should say something too. First of all, I recommend this mailing list http://groups.google.com/group/loongson-dev to those who want to know the latest news about Loongson. If you want to try Gentoo on Yeeloong, you can take this http://www.gentoo-cn.org/~zhangle/loongson_mips3_n32_mplt_20081231.tar.bz2 The file's sha256sum is c94bcd45e58e5f4b8314942a6b3110a2316fd74adb009c8269d1e8e2077d7c72. Please note the userland is N32 ABI, meaning there may be more problems than in O32. But I should've already solved many of them for you. I have been working on Fuloong 2E/2F and Yeeloong's support, particularly N32 ABI system. Firefox is just one example. I have 3 Loongson machines, all donated by lemot...

It is working too. The xulrunner's ebuild is already in loongson overlay . For the mozilla-firefox ebuild, just use the one from mozilla overlay. If you experienced segfault, try to re-emerge sqlite with no optimization. Using the bundled sqlite surely is not an optimal solution, ;) One more thing: Xorg's siliconmotion driver is now working on yeeloong notebook : http://bugs.freedesktop.org/show_bug.cgi?id=21528

My quest for MIPS N32 firefox could finally come to an end, since I just got it scores the same as X86 firefox . Remember I said it would encounter bus error on a few websites in my last related post . But I didn't plan to look into this issue before dealing with cache aliasing problem. However, since Rayson Ho helped me to locate the exact cause of this issue, I decided to finish it first. The problem is caused by unaligned access of ldc1/sdc1 instruction. These two instructions' operand must be 8 bytes aligned. But when crashing, the operand is only 4 bytes aligned. After some discussion and experimenting, I found a workaround for sina.com.cn crashing problem. Yeah, a padding pointer sounds scary and fragile, but it did work. Before posting any comment to this, please make sure you have read all the emails in that thread. Then Fai Wong reported to me that it still crash in acid3 test . So I took another look. This time the problem happened in a different location, and it i...

http://www.linux-mips.org/archives/linux-mips/2009-04/msg00112.html So I confirmed that this MIPS ftrace support is really working. Thanks to Wu Zhangjin (吴章金). However, I have no interest in finding out what kind of difference between my loongson2f patch and wu's caused wu's ftrace patch does not work on top of my loongson 2f patch. What I would like to see now is to get loongson2f patch merged into mainline . Plus, I wish I could make loongson linux to be able to use 4k page(Now, loongson could only use 16k page in order to avoid d-cache aliasing). I have already started working on it now. Even if it turns out that I can't, I could tell others what I have done in order to achieve this goal. And by that time, I would've got a much deeper understanding of Linux's memory management subsystem.

This one is MIPS related, already accepted: MIPS: Fix TIF_32BIT undefined problem when seccomp is disabled This one is proc filesystem related: [PATCH] filp->f_pos not correctly updated in proc_task_readdir The later one is also MIPS related actually, in a peculiar way: MIPS N32 does not have getdents64 system call. And because of readdir's implementation in glibc, this bug will be triggered when trying to run pstree or simply 'ls /proc/xxxx/task', where xxxx is the pid of a multithread process.