Messages in this thread Patch in this message | | | Date | Fri, 18 Nov 2005 18:03:07 +0530 | From | Vivek Goyal <> | Subject | Re: [PATCH 3/10] kdump: export per cpu crash notes pointer through sysfs |
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On Thu, Nov 17, 2005 at 02:07:23PM -0800, Andrew Morton wrote: > Vivek Goyal <vgoyal@in.ibm.com> wrote: > > > > + /* > > + * Might be reading other cpu's data based on which cpu read thread > > + * has been scheduled. But cpu data (memory) is allocated once during > > + * boot up and this data does not change there after. Hence this > > + * operation should be safe. No locking required. > > + */ > > + get_cpu(); > > + addr = __pa(per_cpu_ptr(crash_notes, cpunum)); > > + rc = sprintf(buf, "%Lx\n", addr); > > + put_cpu(); > > I don't think the get_cpu() and put_cpu() are needed here?
Thanks. I have done the changes. Please find attached the incremental patch.
Thanks Vivek
o Removes the call to get_cpu() and put_cpu() as it is not required.
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com> ---
linux-2.6.15-rc1-mm2-1M-root/drivers/base/cpu.c | 2 -- 1 files changed, 2 deletions(-)
diff -puN drivers/base/cpu.c~kdump-export-crash-notes-sysfs-remove-get-cpu drivers/base/cpu.c --- linux-2.6.15-rc1-mm2-1M/drivers/base/cpu.c~kdump-export-crash-notes-sysfs-remove-get-cpu 2005-11-18 16:08:28.000000000 +0530 +++ linux-2.6.15-rc1-mm2-1M-root/drivers/base/cpu.c 2005-11-18 16:08:28.000000000 +0530 @@ -101,10 +101,8 @@ static ssize_t show_crash_notes(struct s * boot up and this data does not change there after. Hence this * operation should be safe. No locking required. */ - get_cpu(); addr = __pa(per_cpu_ptr(crash_notes, cpunum)); rc = sprintf(buf, "%Lx\n", addr); - put_cpu(); return rc; } static SYSDEV_ATTR(crash_notes, 0400, show_crash_notes, NULL); _ - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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