Date: Tue, 7 Mar 2006 22:12:09 +0000 (UTC) From: John Baldwin <jhb@FreeBSD.org> To: src-committers@FreeBSD.org, cvs-src@FreeBSD.org, cvs-all@FreeBSD.org Subject: cvs commit: src/sys/alpha/alpha clock.c src/sys/alpha/include pcpu.h Message-ID: <200603072212.k27MC95R037824@repoman.freebsd.org>
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jhb 2006-03-07 22:12:09 UTC FreeBSD src repository Modified files: sys/alpha/alpha clock.c sys/alpha/include pcpu.h Log: Use the Alpha PCC as a cpu ticker for process runtime accounting. This is slightly more tricky than on x86 as although the PCC is 64-bits, it is not a simple 64-bit counter like the TSC. Instead, the upper 32-bits have PAL-defined behavior and the lower 32-bits run as a free-running 32-bit counter. To handle this, we detect overflows by maintaining a small amount of per-cpu state and use this to simulate the upper 32-bits of the counter providing a full 64-bit counter to the consumers of cpu_ticks(). Revision Changes Path 1.44 +26 -0 src/sys/alpha/alpha/clock.c 1.16 +3 -1 src/sys/alpha/include/pcpu.h
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