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| author | David S. Miller <davem@davemloft.net> | 2011-07-28 05:46:25 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2011-07-28 05:46:25 +0200 |
| commit | 314ff52727fe94dfbe07f3a9a489ab3ca8d8df5a (patch) | |
| tree | df8bbc25ebe7e6f0da73403c5e2b9def2c37f2df /arch/sparc/kernel/pcr.c | |
| parent | sparc: Add T3 sun4v cpu type and hypervisor group defines. (diff) | |
| download | linux-314ff52727fe94dfbe07f3a9a489ab3ca8d8df5a.tar.xz linux-314ff52727fe94dfbe07f3a9a489ab3ca8d8df5a.zip | |
sparc: Don't do expensive hypervisor PCR write unless necessary.
The hypervisor call is only necessary if hypervisor events are
being requested.
So if we're not tracking hypervisor events, simply do a direct
register write.
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'arch/sparc/kernel/pcr.c')
| -rw-r--r-- | arch/sparc/kernel/pcr.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/arch/sparc/kernel/pcr.c b/arch/sparc/kernel/pcr.c index 8ac23e660080..878c6824c732 100644 --- a/arch/sparc/kernel/pcr.c +++ b/arch/sparc/kernel/pcr.c @@ -80,8 +80,11 @@ static void n2_pcr_write(u64 val) { unsigned long ret; - ret = sun4v_niagara2_setperf(HV_N2_PERF_SPARC_CTL, val); - if (ret != HV_EOK) + if (val & PCR_N2_HTRACE) { + ret = sun4v_niagara2_setperf(HV_N2_PERF_SPARC_CTL, val); + if (ret != HV_EOK) + write_pcr(val); + } else write_pcr(val); } |