Re: [Xenomai-core] [PATCH] Add fptest for powerpc
Heikki Lindholm wrote: > > Task 0 is the "idle" taks, an ordinary Linux task > > Task 10 is of type "rtup_ufpp" here, which means that it is a real-time > > task in primary mode using the FPU in primary mode. > > I probably don't have time for debugging for some days now, but if any > of the code goes through sigreturn path, it might be a kernel bug that's > fixed in 2.6.16. Anyway, the patch is applied, thanks. -- Gilles Chanteperdrix. ___ Xenomai-core mailing list Xenomai-core@gna.org https://mail.gna.org/listinfo/xenomai-core
Re: [Xenomai-core] [PATCH] Add fptest for powerpc
Gilles Chanteperdrix kirjoitti: Heikki Lindholm wrote: > This adds powerpc version of fptest.h. It just stores and loads the raw > integer into/from FPU registers without converting to proper IEEE form. > Converting would have added unneccessary complexity. As a side note, the > ppc barfs on the test with "1000 != 10". :I Ok, this test tool is far from being user-friendly :-) Just to be sure, I have tested the latest revision on x86 and it still runs fine, so I guess there really is a bug in power pc fpu switching code. Now, if we decode a bit, the integer passed to fp_regs_set and fp_regs_check are 1000 * iterations + task_index, so 1000 is task 0, iteration 1 10 is task 10, iteration 0. It means that task 10 after returning from its first context switch, is getting the context of task 0 before its second context switch. Now the thing to try is to reduce the number of threads involved, since by default there are 23 threads, so you should add a printk for each context switch in the kernel driver (and now that I think about it this printk should be activable with an ioctl), and try and reduce the list of threads by removing threads which do not appear between the serie of switches from task 0 to task 10. The correspondance between the task numbers and their type is not easy, but /proc/xenomai/sched and switch --help should help... Task 0 is the "idle" taks, an ordinary Linux task Task 10 is of type "rtup_ufpp" here, which means that it is a real-time task in primary mode using the FPU in primary mode. I probably don't have time for debugging for some days now, but if any of the code goes through sigreturn path, it might be a kernel bug that's fixed in 2.6.16. -- hl ___ Xenomai-core mailing list Xenomai-core@gna.org https://mail.gna.org/listinfo/xenomai-core
Re: [Xenomai-core] [PATCH] Add fptest for powerpc
Heikki Lindholm wrote: > This adds powerpc version of fptest.h. It just stores and loads the raw > integer into/from FPU registers without converting to proper IEEE form. > Converting would have added unneccessary complexity. As a side note, the > ppc barfs on the test with "1000 != 10". :I Ok, this test tool is far from being user-friendly :-) Just to be sure, I have tested the latest revision on x86 and it still runs fine, so I guess there really is a bug in power pc fpu switching code. Now, if we decode a bit, the integer passed to fp_regs_set and fp_regs_check are 1000 * iterations + task_index, so 1000 is task 0, iteration 1 10 is task 10, iteration 0. It means that task 10 after returning from its first context switch, is getting the context of task 0 before its second context switch. Now the thing to try is to reduce the number of threads involved, since by default there are 23 threads, so you should add a printk for each context switch in the kernel driver (and now that I think about it this printk should be activable with an ioctl), and try and reduce the list of threads by removing threads which do not appear between the serie of switches from task 0 to task 10. The correspondance between the task numbers and their type is not easy, but /proc/xenomai/sched and switch --help should help... Task 0 is the "idle" taks, an ordinary Linux task Task 10 is of type "rtup_ufpp" here, which means that it is a real-time task in primary mode using the FPU in primary mode. -- Gilles Chanteperdrix. ___ Xenomai-core mailing list Xenomai-core@gna.org https://mail.gna.org/listinfo/xenomai-core
[Xenomai-core] [PATCH] Add fptest for powerpc
This adds powerpc version of fptest.h. It just stores and loads the raw
integer into/from FPU registers without converting to proper IEEE form.
Converting would have added unneccessary complexity. As a side note, the
ppc barfs on the test with "1000 != 10". :I
-- hl
diff -Nru xenomai.orig/include/asm-powerpc/fptest.h
xenomai/include/asm-powerpc/fptest.h
--- xenomai.orig/include/asm-powerpc/fptest.h 2006-06-10 10:29:29.335736000
+
+++ xenomai/include/asm-powerpc/fptest.h2006-06-10 16:12:09.395132000
+
@@ -10,11 +10,94 @@
static inline void fp_regs_set(unsigned val)
{
+ uint64_t fpval = val;
+ __asm__ __volatile__("lfd 0, %0\n"
+ " fmr 1, 0\n"
+ " fmr 2, 0\n"
+ " fmr 3, 0\n"
+ " fmr 4, 0\n"
+ " fmr 5, 0\n"
+ " fmr 6, 0\n"
+ " fmr 7, 0\n"
+ " fmr 8, 0\n"
+ " fmr 9, 0\n"
+ " fmr 10, 0\n"
+ " fmr 11, 0\n"
+ " fmr 12, 0\n"
+ " fmr 13, 0\n"
+ " fmr 14, 0\n"
+ " fmr 15, 0\n"
+ " fmr 16, 0\n"
+ " fmr 17, 0\n"
+ " fmr 18, 0\n"
+ " fmr 19, 0\n"
+ " fmr 20, 0\n"
+ " fmr 21, 0\n"
+ " fmr 22, 0\n"
+ " fmr 23, 0\n"
+ " fmr 24, 0\n"
+ " fmr 25, 0\n"
+ " fmr 26, 0\n"
+ " fmr 27, 0\n"
+ " fmr 28, 0\n"
+ " fmr 29, 0\n"
+ " fmr 30, 0\n"
+ " fmr 31, 0\n"
+ :
+ : "m" (fpval));
}
+#define FPTEST_REGVAL(n) { \
+ uint64_t t; \
+ __asm__ __volatile__(" stfd" #n ", %0" : "=m" (t));\
+ e[n] = (unsigned)t; \
+ }
+
static inline int fp_regs_check(unsigned val)
{
-return 0;
+ unsigned i, failed = 0;
+ uint32_t e[32];
+
+ FPTEST_REGVAL(0);
+ FPTEST_REGVAL(1);
+ FPTEST_REGVAL(2);
+ FPTEST_REGVAL(3);
+ FPTEST_REGVAL(4);
+ FPTEST_REGVAL(5);
+ FPTEST_REGVAL(6);
+ FPTEST_REGVAL(7);
+ FPTEST_REGVAL(8);
+ FPTEST_REGVAL(9);
+ FPTEST_REGVAL(10);
+ FPTEST_REGVAL(11);
+ FPTEST_REGVAL(12);
+ FPTEST_REGVAL(13);
+ FPTEST_REGVAL(14);
+ FPTEST_REGVAL(15);
+ FPTEST_REGVAL(16);
+ FPTEST_REGVAL(17);
+ FPTEST_REGVAL(18);
+ FPTEST_REGVAL(19);
+ FPTEST_REGVAL(20);
+ FPTEST_REGVAL(21);
+ FPTEST_REGVAL(22);
+ FPTEST_REGVAL(23);
+ FPTEST_REGVAL(24);
+ FPTEST_REGVAL(25);
+ FPTEST_REGVAL(26);
+ FPTEST_REGVAL(27);
+ FPTEST_REGVAL(28);
+ FPTEST_REGVAL(29);
+ FPTEST_REGVAL(30);
+ FPTEST_REGVAL(31);
+
+ for (i = 0; i < 32; i++)
+ if (e[i] != val) {
+ printk("r%d: %u != %u\n", i, e[i], val);
+ failed = 1;
+ }
+
+ return failed;
}
#endif /* FPTEST_H */
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