From 43ca106fa8ec7d684776fbe561214d3b2b7cb9cb Mon Sep 17 00:00:00 2001 From: Minchan Kim Date: Tue, 4 May 2021 18:37:28 -0700 Subject: mm: cma: support sysfs Since CMA is getting used more widely, it's more important to keep monitoring CMA statistics for system health since it's directly related to user experience. This patch introduces sysfs statistics for CMA, in order to provide some basic monitoring of the CMA allocator. * the number of CMA page successful allocations * the number of CMA page allocation failures These two values allow the user to calcuate the allocation failure rate for each CMA area. e.g.) /sys/kernel/mm/cma/WIFI/alloc_pages_[success|fail] /sys/kernel/mm/cma/SENSOR/alloc_pages_[success|fail] /sys/kernel/mm/cma/BLUETOOTH/alloc_pages_[success|fail] The cma_stat was intentionally allocated by dynamic allocation to harmonize with kobject lifetime management. https://lore.kernel.org/linux-mm/YCOAmXqt6dZkCQYs@kroah.com/ Link: https://lkml.kernel.org/r/20210324230759.2213957-1-minchan@kernel.org Link: https://lore.kernel.org/linux-mm/20210316100433.17665-1-colin.king@canonical.com/ Signed-off-by: Minchan Kim Signed-off-by: Colin Ian King Tested-by: Dmitry Osipenko Reviewed-by: Dmitry Osipenko Reviewed-by: Greg Kroah-Hartman Reviewed-by: John Hubbard Tested-by: Anders Roxell Cc: Suren Baghdasaryan Cc: John Dias Cc: Matthew Wilcox (Oracle) Cc: Colin Ian King Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/Kconfig | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'mm/Kconfig') diff --git a/mm/Kconfig b/mm/Kconfig index f4ceeaedb966..5f7d7b3d8cc2 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -518,6 +518,13 @@ config CMA_DEBUGFS help Turns on the DebugFS interface for CMA. +config CMA_SYSFS + bool "CMA information through sysfs interface" + depends on CMA && SYSFS + help + This option exposes some sysfs attributes to get information + from CMA. + config CMA_AREAS int "Maximum count of the CMA areas" depends on CMA -- cgit v1.2.3