From 19d7c3adfdd4adbd286429849ac22ce9cce32477 Mon Sep 17 00:00:00 2001 From: SeongJae Park Date: Tue, 10 Dec 2024 13:50:26 -0800 Subject: [PATCH] samples: add a skeleton of a sample DAMON module for working set size estimation Patch series "mm/damon: add sample modules". Implement a proactive cold memory regions reclaiming logic of prcl sample module using DAMOS. The logic treats memory regions that not accessed at all for five or more seconds as cold, and reclaim those as soon as found. This patch (of 5): Add a skeleton for a sample DAMON static module that can be used for estimating working set size of a given process. Note that it is a static module since DAMON is not exporting symbols to loadable modules for now. It exposes two module parameters, namely 'pid' and 'enable'. 'pid' will specify the process that the module will estimate the working set size of. 'enable' will receive whether to start or stop the estimation. Because this is just a skeleton, the parameters do nothing, though. The functionalities will be implemented by following commits. Link: https://lkml.kernel.org/r/20241210215030.85675-1-sj@kernel.org Link: https://lkml.kernel.org/r/20241210215030.85675-2-sj@kernel.org Signed-off-by: SeongJae Park Signed-off-by: Andrew Morton --- MAINTAINERS | 1 + samples/Kconfig | 2 ++ samples/Makefile | 1 + samples/damon/Kconfig | 17 +++++++++++ samples/damon/Makefile | 3 ++ samples/damon/wsse.c | 65 ++++++++++++++++++++++++++++++++++++++++++ 6 files changed, 89 insertions(+) create mode 100644 samples/damon/Kconfig create mode 100644 samples/damon/Makefile create mode 100644 samples/damon/wsse.c diff --git a/MAINTAINERS b/MAINTAINERS index 30cbc3d44cd5..46e4ccf18c99 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -6330,6 +6330,7 @@ F: Documentation/mm/damon/ F: include/linux/damon.h F: include/trace/events/damon.h F: mm/damon/ +F: samples/damon/ F: tools/testing/selftests/damon/ DAVICOM FAST ETHERNET (DMFE) NETWORK DRIVER diff --git a/samples/Kconfig b/samples/Kconfig index b288d9991d27..8d5a36f0e5d6 100644 --- a/samples/Kconfig +++ b/samples/Kconfig @@ -293,6 +293,8 @@ config SAMPLE_CGROUP source "samples/rust/Kconfig" +source "samples/damon/Kconfig" + endif # SAMPLES config HAVE_SAMPLE_FTRACE_DIRECT diff --git a/samples/Makefile b/samples/Makefile index b85fa64390c5..726bb5293486 100644 --- a/samples/Makefile +++ b/samples/Makefile @@ -39,3 +39,4 @@ obj-$(CONFIG_SAMPLE_KMEMLEAK) += kmemleak/ obj-$(CONFIG_SAMPLE_CORESIGHT_SYSCFG) += coresight/ obj-$(CONFIG_SAMPLE_FPROBE) += fprobe/ obj-$(CONFIG_SAMPLES_RUST) += rust/ +obj-$(CONFIG_SAMPLE_DAMON_WSSE) += damon/ diff --git a/samples/damon/Kconfig b/samples/damon/Kconfig new file mode 100644 index 000000000000..b799e01345c8 --- /dev/null +++ b/samples/damon/Kconfig @@ -0,0 +1,17 @@ +# SPDX-License-Identifier: GPL-2.0 + +menu "DAMON Samples" + +config SAMPLE_DAMON_WSSE + bool "DAMON sameple module for working set size estimation" + depends on DAMON && DAMON_VADDR + help + This builds DAMON sample module for working set size estimation. + + The module receives a pid, monitor access to the virtual address + space of the process, estimate working set size of the process, and + repeatedly prints the size on the kernel log. + + If unsure, say N. + +endmenu diff --git a/samples/damon/Makefile b/samples/damon/Makefile new file mode 100644 index 000000000000..ccbe93d40130 --- /dev/null +++ b/samples/damon/Makefile @@ -0,0 +1,3 @@ +# SPDX-License-Identifier: GPL-2.0 + +obj-$(CONFIG_SAMPLE_DAMON_WSSE) += wsse.o diff --git a/samples/damon/wsse.c b/samples/damon/wsse.c new file mode 100644 index 000000000000..7f2cb76a1a70 --- /dev/null +++ b/samples/damon/wsse.c @@ -0,0 +1,65 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * working set size estimation: monitor access pattern of given process and + * print estimated working set size (total size of regions that showing some + * access). + */ + +#define pr_fmt(fmt) "damon_sample_wsse: " fmt + +#include +#include +#include +#include + +static int target_pid __read_mostly; +module_param(target_pid, int, 0600); + +static int damon_sample_wsse_enable_store( + const char *val, const struct kernel_param *kp); + +static const struct kernel_param_ops enable_param_ops = { + .set = damon_sample_wsse_enable_store, + .get = param_get_bool, +}; + +static bool enable __read_mostly; +module_param_cb(enable, &enable_param_ops, &enable, 0600); +MODULE_PARM_DESC(enable, "Enable or disable DAMON_SAMPLE_WSSE"); + +static int damon_sample_wsse_start(void) +{ + pr_info("start\n"); + return 0; +} + +static void damon_sample_wsse_stop(void) +{ + pr_info("stop\n"); +} + +static int damon_sample_wsse_enable_store( + const char *val, const struct kernel_param *kp) +{ + bool enabled = enable; + int err; + + err = kstrtobool(val, &enable); + if (err) + return err; + + if (enable == enabled) + return 0; + + if (enable) + return damon_sample_wsse_start(); + damon_sample_wsse_stop(); + return 0; +} + +static int __init damon_sample_wsse_init(void) +{ + return 0; +} + +module_init(damon_sample_wsse_init); -- 2.50.1