From 1f84c2624a2d75c9f69214ed83f11dd30a8ae83d Mon Sep 17 00:00:00 2001 From: Rashmica Gupta Date: Thu, 1 Jun 2017 15:34:40 +1000 Subject: [PATCH] Add documentation for the powerpc memtrace debugfs files CONFIG_PPC_MEMTRACE must be set to use this feature. This can only be used on powernv platforms. Signed-off-by: Rashmica Gupta [mpe: Update dates and kernel versions, mention size is in bytes] Signed-off-by: Michael Ellerman --- Documentation/ABI/testing/ppc-memtrace | 45 ++++++++++++++++++++++++++++++++++ 1 file changed, 45 insertions(+) create mode 100644 Documentation/ABI/testing/ppc-memtrace diff --git a/Documentation/ABI/testing/ppc-memtrace b/Documentation/ABI/testing/ppc-memtrace new file mode 100644 index 000000000000..2e8b93741270 --- /dev/null +++ b/Documentation/ABI/testing/ppc-memtrace @@ -0,0 +1,45 @@ +What: /sys/kernel/debug/powerpc/memtrace +Date: Aug 2017 +KernelVersion: 4.14 +Contact: linuxppc-dev@lists.ozlabs.org +Description: This folder contains the relevant debugfs files for the + hardware trace macro to use. CONFIG_PPC64_HARDWARE_TRACING + must be set. + +What: /sys/kernel/debug/powerpc/memtrace/enable +Date: Aug 2017 +KernelVersion: 4.14 +Contact: linuxppc-dev@lists.ozlabs.org +Description: Write an integer containing the size in bytes of the memory + you want removed from each NUMA node to this file - it must be + aligned to the memblock size. This amount of RAM will be removed + from the kernel mappings and the following debugfs files will be + created. This can only be successfully done once per boot. Once + memory is successfully removed from each node, the following + files are created. + +What: /sys/kernel/debug/powerpc/memtrace/ +Date: Aug 2017 +KernelVersion: 4.14 +Contact: linuxppc-dev@lists.ozlabs.org +Description: This directory contains information about the removed memory + from the specific NUMA node. + +What: /sys/kernel/debug/powerpc/memtrace//size +Date: Aug 2017 +KernelVersion: 4.14 +Contact: linuxppc-dev@lists.ozlabs.org +Description: This contains the size of the memory removed from the node. + +What: /sys/kernel/debug/powerpc/memtrace//start +Date: Aug 2017 +KernelVersion: 4.14 +Contact: linuxppc-dev@lists.ozlabs.org +Description: This contains the start address of the removed memory. + +What: /sys/kernel/debug/powerpc/memtrace//trace +Date: Aug 2017 +KernelVersion: 4.14 +Contact: linuxppc-dev@lists.ozlabs.org +Description: This is where the hardware trace macro will output the trace + it generates. -- 2.11.0