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perf(1)
=======

NAME
----
perf - Performance analysis tools for Linux

SYNOPSIS
--------
[verse]
'perf' [--version] [--help] [OPTIONS] COMMAND [ARGS]

OPTIONS
-------
--debug::
	Setup debug variable (see list below) in value
	range (0, 10). Use like:
	  --debug verbose   # sets verbose = 1
	  --debug verbose=2 # sets verbose = 2

	List of debug variables allowed to set:
	  verbose          - general debug messages
	  ordered-events   - ordered events object debug messages
	  data-convert     - data convert command debug messages

--buildid-dir::
	Setup buildid cache directory. It has higher priority than
	buildid.dir config file option.

-v::
--version::
  Display perf version.

-h::
--help::
  Run perf help command.

DESCRIPTION
-----------
Performance counters for Linux are a new kernel-based subsystem
that provide a framework for all things performance analysis. It
covers hardware level (CPU/PMU, Performance Monitoring Unit) features
and software features (software counters, tracepoints) as well.

SEE ALSO
--------
linkperf:perf-stat[1], linkperf:perf-top[1],
linkperf:perf-record[1], linkperf:perf-report[1],
linkperf:perf-list[1]
-subject'>x86/microcode/intel: Drop stashed AP patch pointer optimization
This was meant to save us the scanning of the microcode containter in the initrd since the first AP had already done that but it can also hurt us: Imagine a single hyperthreaded CPU (Intel(R) Atom(TM) CPU N270, for example) which updates the microcode on the BSP but since the microcode engine is shared between the two threads, the update on CPU1 doesn't happen because it has already happened on CPU0 and we don't find a newer microcode revision on CPU1. Which doesn't set the intel_ucode_patch pointer and at initrd jettisoning time we don't save the microcode patch for later application. Now, when we suspend to RAM, the loaded microcode gets cleared so we need to reload but there's no patch saved in the cache. Removing the optimization fixes this issue and all is fine and dandy. Fixes: 06b8534cb728 ("x86/microcode: Rework microcode loading") Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20170120202955.4091-2-bp@alien8.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'sound/isa/es1688/Makefile')