https://github.com/torvalds/linux
Revision 8997b185119966c62c6e95e7b010b4060407e358 authored by Srivatsa S. Bhat on 28 April 2014, 18:54:58 UTC, committed by Rafael J. Wysocki on 28 April 2014, 23:22:54 UTC
During frequency transitions, the cpufreq core takes the responsibility of
invoking cpufreq_freq_transition_begin() and cpufreq_freq_transition_end()
for those cpufreq drivers that define the ->target_index callback but don't
set the ASYNC_NOTIFICATION flag.

The powernow-k7 cpufreq driver falls under this category, but this driver was
invoking the _begin() and _end() APIs itself around frequency transitions,
which led to double invocation of the _begin() API. The _begin API makes
contending callers wait until the previous invocation is complete. Hence,
the powernow-k7 driver ended up waiting on itself, leading to system hangs
during boot.

Fix this by removing the calls to the _begin() and _end() APIs from the
powernow-k7 driver, since they rightly belong to the cpufreq core.

Fixes: 12478cf0c55e (cpufreq: Make sure frequency transitions are serialized)
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
1 parent 3221e55
History
Tip revision: 8997b185119966c62c6e95e7b010b4060407e358 authored by Srivatsa S. Bhat on 28 April 2014, 18:54:58 UTC
cpufreq: powernow-k7: Fix double invocation of cpufreq_freq_transition_begin/end
Tip revision: 8997b18
File Mode Size
Makefile -rw-r--r-- 191 bytes
us122l.c -rw-r--r-- 18.9 KB
us122l.h -rw-r--r-- 540 bytes
usX2Yhwdep.c -rw-r--r-- 7.3 KB
usX2Yhwdep.h -rw-r--r-- 122 bytes
usb_stream.c -rw-r--r-- 19.0 KB
usb_stream.h -rw-r--r-- 2.6 KB
usbus428ctldefs.h -rw-r--r-- 2.1 KB
usbusx2y.c -rw-r--r-- 13.2 KB
usbusx2y.h -rw-r--r-- 2.0 KB
usbusx2yaudio.c -rw-r--r-- 28.5 KB
usx2y.h -rw-r--r-- 1.5 KB
usx2yhwdeppcm.c -rw-r--r-- 23.8 KB
usx2yhwdeppcm.h -rw-r--r-- 507 bytes

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