Athira Rajeev
82715a0f33
powerpc/perf: Fix reading of MSR[HV/PR] bits in trace-imc
IMC trace-mode uses MSR[HV/PR] bits to set the cpumode for the instruction pointer captured in each sample. The bits are fetched from the third double word of the trace record. Reading third double word from IMC trace record should use be64_to_cpu() along with READ_ONCE inorder to fetch correct MSR[HV/PR] bits. Patch addresses this change. Currently we are using PERF_RECORD_MISC_HYPERVISOR as cpumode if MSR HV is 1 and PR is 0 which means the address is from host counter. But using PERF_RECORD_MISC_HYPERVISOR for host counter data will fail to resolve the address -> symbol during "perf report" because perf tools side uses PERF_RECORD_MISC_KERNEL to represent the host counter data. Therefore, fix the trace imc sample data to use PERF_RECORD_MISC_KERNEL as cpumode for host kernel information. Fixes: 77ca3951cc37 ("powerpc/perf: Add kernel support for new MSR[HV PR] bits in trace-imc") Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/1598424029-1662-1-git-send-email-atrajeev@linux.vnet.ibm.com
Linux kernel ============ There are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. Please read Documentation/admin-guide/README.rst first. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. The formatted documentation can also be read online at: https://www.kernel.org/doc/html/latest/ There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.
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