Re: [RFC 2/2] perf: Marker software event and ioctl

On 09/12/2014 08:57 AM, Pawel Moll wrote:

On Fri, 2014-09-12 at 13:43 +0100, Christopher Covington wrote:

quoted

Just to ask the dumb questions in case the answers I've come up with are
wrong: What is PAGE_SIZE on an arm64 kernel? 

It's either 4 or 64k, depending on CONFIG_ARM64_64K_PAGES.

quoted

How does userspace know?

#include <unistd.h>
#include <stdio.h>

int main(void)
{
	printf("%ld\n", sysconf(_SC_PAGESIZE));
	return 0;
}

Oh excellent, that actually works. Based on a misreading of the glibc code I
thought it was hard-coded to 64K.

Thanks,
Christopher

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