Add a sample DAMON application kernel module, namely damon_sample_wsse. It is same to the one of the example kernel modules that presented at kernel summit 2021 with 10 minutes live coding[1] but updated for the latest DAMON interface. The sample module receives a pid of a process to monitor the access, monitors the access to the virtual address space of the process, calculate estimated working set size, and repeatedly print it on the kernel log. [1] https://linuxplumbersconf.org/event/11/contributions/984/ Signed-off-by: SeongJae Park <sj@xxxxxxxxxx> --- MAINTAINERS | 1 + samples/Kconfig | 2 + samples/Makefile | 2 + samples/damon/Kconfig | 17 +++++++ samples/damon/Makefile | 2 + samples/damon/damon_sample_wsse.c | 85 +++++++++++++++++++++++++++++++ 6 files changed, 109 insertions(+) create mode 100644 samples/damon/Kconfig create mode 100644 samples/damon/Makefile create mode 100644 samples/damon/damon_sample_wsse.c diff --git a/MAINTAINERS b/MAINTAINERS index d1fcae09c910..5a44258810ef 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -5764,6 +5764,7 @@ 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..5af6bb8afb07 100644 --- a/samples/Makefile +++ b/samples/Makefile @@ -39,3 +39,5 @@ obj-$(CONFIG_SAMPLE_KMEMLEAK) += kmemleak/ obj-$(CONFIG_SAMPLE_CORESIGHT_SYSCFG) += coresight/ obj-$(CONFIG_SAMPLE_FPROBE) += fprobe/ obj-$(CONFIG_SAMPLES_RUST) += rust/ +obj-$(CONFIG_SAMPLE_DAMON_WSSE) += damon/ +obj-$(CONFIG_SAMPLE_DAMON_PRCL) += damon/ diff --git a/samples/damon/Kconfig b/samples/damon/Kconfig new file mode 100644 index 000000000000..f8b9a73717f9 --- /dev/null +++ b/samples/damon/Kconfig @@ -0,0 +1,17 @@ +# SPDX-License-Identifier: GPL-2.0 + +menu "DAMON Samples" + +config SAMPLE_DAMON_WSSE + tristate "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 pid of a process, monitor access to the virtual + address space of the process, calculate the estimated working set + size of the process, and repeatedly print 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..1ace3ad4aff0 --- /dev/null +++ b/samples/damon/Makefile @@ -0,0 +1,2 @@ +# SPDX-License-Identifier: GPL-2.0 +obj-$(CONFIG_SAMPLE_DAMON_WSSE) += damon_sample_wsse.o diff --git a/samples/damon/damon_sample_wsse.c b/samples/damon/damon_sample_wsse.c new file mode 100644 index 000000000000..897e6b136a1a --- /dev/null +++ b/samples/damon/damon_sample_wsse.c @@ -0,0 +1,85 @@ +// 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 <linux/damon.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> + +static int target_pid __read_mostly; +module_param(target_pid, int, 0600); + +static struct damon_ctx *ctx; +static struct pid *target_pidp; + +static int damon_sample_wsse_after_aggregate(struct damon_ctx *c) +{ + struct damon_target *t; + + damon_for_each_target(t, c) { + struct damon_region *r; + unsigned long wss = 0; + + damon_for_each_region(r, t) { + if (r->nr_accesses > 0) + wss += r->ar.end - r->ar.start; + } + pr_info("wss: %lu\n", wss); + } + return 0; +} + +static int __init damon_sample_wsse_init(void) +{ + struct damon_target *target; + + pr_info("Hello\n"); + + ctx = damon_new_ctx(); + if (!ctx) + return -ENOMEM; + if (damon_select_ops(ctx, DAMON_OPS_VADDR)) { + damon_destroy_ctx(ctx); + return -EINVAL; + } + + target = damon_new_target(); + if (!target) { + damon_destroy_ctx(ctx); + return -ENOMEM; + } + damon_add_target(ctx, target); + target_pidp = find_get_pid(target_pid); + if (!target_pidp) { + damon_destroy_ctx(ctx); + return -EINVAL; + } + target->pid = target_pidp; + + ctx->callback.after_aggregation = damon_sample_wsse_after_aggregate; + return damon_start(&ctx, 1, true); +} + +static void __exit damon_sample_wsse_exit(void) +{ + pr_info("Goodbye\n"); + if (ctx) { + damon_stop(&ctx, 1); + damon_destroy_ctx(ctx); + } + if (target_pidp) + put_pid(target_pidp); +} + +module_init(damon_sample_wsse_init); +module_exit(damon_sample_wsse_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("SeongJae Park"); +MODULE_DESCRIPTION("DAMON sample module for working set size estimation"); -- 2.34.1
