Hi Dave, Thank you for welcome, review and testing. >You've come to the right place... ;-) > >And your patch submission is fine, although I do prefer that you send the >the patches as email attachments instead of inline. (Although that's my >problem because of the Zimbra email client that I use) Ok, I attach V2 patches. [PATCH 3/4] is updated. >I tested your patch with two kernel types, one of them the "legacy" version >with "pcpu_num_used" and "pcpu_size" symbols (RHEL5), and the second one with >current kernels with the "pcpu_reserved_chunk_limit" symbol (RHEL6 and 2.6.37-rc1). > >Here's what I see, first without, and then with your patch applied. >In any case, there's no way I can change the st->__per_cpu_end values >as you propose -- even if it somehow works with your testing. > >Comments? I did some wrong changes and would understand your mentions. Updating __per_cpu_end itself makes original UI's corruption. And for sure, I want __per_cpu_end to be bumped with your guess. I fixed these bugs like attachments and tested again, of course checked st->__per_cpu_end value advised from you. One more update is to add is_per_cpu_range(). Because there are some conditions about percpu range in symbols.c, I think it is better to use common function than inline. The function returns 0 (not percpu), 1 (kernels) and 2 (modules) although callers do not distinguish between 1 and 2 now. Thanks, Toshi >(1) Testing with a 2.6.18-based RHEL5 kernel: > > Without your patch, the stored __per_cpu_start and __per_cpu_end > values are as shown here in the symbol_table_data structure: > > crash> help -s > ... > __per_cpu_start: ffffffff80419000 > __per_cpu_end: ffffffff8041f508 > ... > > which reflect the beginning and end of the __per_cpu kernel > symbol range: > > crash> sym -l > ... > ffffffff80419000 (A) __per_cpu_start > ffffffff80419000 (D) per_cpu__init_tss > ffffffff8041b080 (D) per_cpu__orig_ist > ffffffff8041b100 (d) per_cpu__idle_state > ... > ffffffff8041f480 (d) per_cpu__flow_flush_tasklets > ffffffff8041f4c0 (d) per_cpu__rt_cache_stat > ffffffff8041f500 (d) per_cpu____icmp_socket > ffffffff8041f508 (A) __per_cpu_end > > With your patch applied, the __per_cpu_end gets incremented based > upon the "pcpu_num_used" and "pcpu_size" contents: > > crash> help -s > ... > __per_cpu_start: ffffffff80419000 > __per_cpu_end: ffffffff80427a10 > ... > > But that doesn't seem right, because the resultant value > pushes it into the bss symbol range: > > crash> sym ffffffff80427a10 > ffffffff80427a10 (B) boot_exception_stacks+6672 > crash> > > crash> sym -l > ... > ffffffff8041f4c0 (d) per_cpu__rt_cache_stat > ffffffff8041f500 (d) per_cpu____icmp_socket > ffffffff8041f508 (A) __per_cpu_end <-- original value > ffffffff80420000 (d) .data_nosave > ffffffff80420000 (A) __nosave_begin > ffffffff80420000 (D) in_suspend > ffffffff80421000 (b) .bss > ffffffff80421000 (A) __bss_start > ffffffff80421000 (A) __nosave_end > ffffffff80421000 (B) empty_zero_page > ffffffff80422000 (B) boot_cpu_stack > ffffffff80426000 (B) boot_exception_stacks <-- bumped to ffffffff80427a10 > ffffffff8042c000 (B) idt_table > ffffffff8042d000 (B) boot_delay > ffffffff8042d008 (B) printk_delay_msec > ... > >(2) Testing with a 2.6.32-based RHEL6 kernel: > > Without your patch, the stored __per_cpu_start and __per_cpu_end > values are as shown here in the symbol_table_data structure: > > crash> help -s > ... > __per_cpu_start: 0 > __per_cpu_end: 17358 > ... > > which reflect the beginning and end of the kernel's __per_cpu > symbol range: > > crash> sym -l > 0 (D) __per_cpu_start > 0 (V) per_cpu__irq_stack_union > 4000 (V) per_cpu__gdt_page > 5000 (V) per_cpu__exception_stacks > ... > 16940 (V) per_cpu__cpu_tlbstate > 16980 (V) per_cpu__runqueues > 17340 (V) per_cpu__sched_clock_data > 17358 (D) __per_cpu_end > ffffffff81000000 (T) _text > ... > > With your patch applied, the st->__per_cpu_end value gets changed > like so: > > crash> help -s > ... > __per_cpu_start: 0 > __per_cpu_end: ffffffff81bf36b8 > ... > > But that doesn't seem right, where ffffffff81bf36b8 is the > "pcpu_reserved_chunk_limit" symbol value: > > crash> sym ffffffff81bf36b8 > ffffffff81bf36b8 (b) pcpu_reserved_chunk_limit > crash> > > I'm guessing that you want it st->__per_cpu_end to be bumped from > 0x17358 to 0x19358: > > crash> px pcpu_reserved_chunk_limit > pcpu_reserved_chunk_limit = $4 = 0x19358 > crash> > >(3) Testing with a generic upstream 2.6.37-rc1 kernel, I see the same > behaviour as with the RHEL6 kernel. > >In any case, there's no way I can change the st->__per_cpu_end values >as you propose -- even if it somehow works with your testing. > >Comments? > >Dave
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0004-update-cmd_p.patch
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0001-Add-percpu-member.patch
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0002-module-s-percpu-basic-procedure.patch
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0003-expand-percpu-area~1.patch
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