From 034dd340b08be1f2f0477ad16131d609f9dbd53c Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 30 Aug 2026 09:22:00 -0700 Subject: Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixes from Steven Rostedt: - Fix error output of boot instance creation failure Currently if a boot instance creation fails, instead of printing out the name of the instance that failed, it prints "(null)". That is because it prints "cur_str" that had already been processed by strsep(). Print the saved name instead. While at it, print the error code of the failure. - Fix use-after-free for same named historgrams Histograms can be named so that they can be used in multiple events. But if the named histogram has a variable attached, the second event that uses the named histogram which duplicates it and needs to free the original after duplication leaves the old variable in place and still visible. If another histogram uses than variable, it will use the stale one which will try to reference the freed duplicate histogram and crash the kernel. Free the duplicate variables along with the duplicated histogram data. - Check return value of kthread_run() in event self test The events self tests uses a kthread for testing but does not check if it succeeded in creating a kthread. If the kthread creation were to fail, the code will still try to call kthread_stop() on the error returned. - Fix race between reading trace_pipe and updating subbuffer size If a user is reading the trace_pipe file at the same time they update the ring buffer sub-buffer size, can cause the trace_pipe read to read stale data. Add trace_access_lock() around updating the ring buffer sub-buffer size. - Fix eventfs_inode on failure path in creation of the events directory In the creation of the "events" directory, if after allocating the eventfs_inode a failure is detected, it calls cleanup_ei() which calls free_ei(). The free_ei() will test if eventfs_inode being freed has no children. It is a bug if it does. But on the failure case of the creation of the "events" directory, the children lists have not yet been initialized and the free will trigger a warning because list_empty() on an uninitialized list returns false. Move the initialization into init_ei() where it makes more sense and makes sure that a created eventfs_inode has its lists initialized upon creation. - Check return value of kthread_run() in ftrace direct sample code The sample code that shows how to use the ftrace direct calls does not test the return of kthread_run() to see if it succeeds. Return a failure if the kthread_run() doesn't succeed. - Clear user events state on fork in case of alloc failure On fork, the child gets a pointer to the parent's user events state. It makes a copy of it then updates the child's pointer to it. But if the allocation fails, the duplication function leaves the child with a pointer to its parent's descriptor. When the child cleans up its data, it will free the parent's descriptor while the parent is still using it. In the duplication function, set the child's user_event_mm to NULL before testing if the allocation succeeded, and when it exits it will not free the parent's descriptor. - Fix retry exhaustion in simple ring buffer reader swap simple_ring_buffer_swap_reader_page() starts with retry set to 8 and post-decrements it only after a failed link replacement. On the final attempt, a successful replacement leaves retry at zero, while a failed replacement leaves it at -1. But the check for success expects the retry value to be non-zero and exits with an error on zero. This is the opposite result. Fix it. - Fail nicely when the remote swap_reader_page() returns an error Currently, if the swap_reader_page() of a remote buffer fails, it triggers a WARN_ON_ONCE() and continues normally. Instead, have it exit with an error and a pr_warn() print instead of a full WARNING. * tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: ring-buffer: Stop remote reader update when page swap fails tracing: Fix retry exhaustion in simple ring buffer reader swap tracing/user_events: Clear copied tracing state before fork duplication samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify eventfs: Initialize ei->children and ei->list in init_ei() tracing: Fix use-after-free in trace_pipe read on sub-buffer order change tracing: Fix crash passing ERR_PTR to kthread_stop() tracing: Fix use-after-free with same-name named triggers tracing: Fix logged instance name on creation failure --- samples/damon/Kconfig | 43 +++++++++ samples/damon/Makefile | 5 + samples/damon/mtier.c | 255 +++++++++++++++++++++++++++++++++++++++++++++++++ samples/damon/prcl.c | 174 +++++++++++++++++++++++++++++++++ samples/damon/wsse.c | 154 +++++++++++++++++++++++++++++ 5 files changed, 631 insertions(+) create mode 100644 samples/damon/Kconfig create mode 100644 samples/damon/Makefile create mode 100644 samples/damon/mtier.c create mode 100644 samples/damon/prcl.c create mode 100644 samples/damon/wsse.c (limited to 'samples/damon') diff --git a/samples/damon/Kconfig b/samples/damon/Kconfig new file mode 100644 index 000000000..00be3e6bd --- /dev/null +++ b/samples/damon/Kconfig @@ -0,0 +1,43 @@ +# SPDX-License-Identifier: GPL-2.0 + +menu "DAMON Samples" + +config SAMPLE_DAMON_WSSE + bool "DAMON sample 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. + +config SAMPLE_DAMON_PRCL + bool "DAMON sample module for access-aware proactive reclamation" + depends on DAMON && DAMON_VADDR + help + This builds DAMON sample module for access-aware proactive + reclamation. + + The module receives a pid, monitor access to the virtual address + space of the process, find memory regions that not accessed, and + proactively reclaim the regions. + + If unsure, say N. + +config SAMPLE_DAMON_MTIER + bool "DAMON sample module for memory tiering" + depends on DAMON && DAMON_PADDR + help + This builds DAMON sample module for memory tiering. + + The module assumes the system is constructed with two NUMA nodes, + which seems as local and remote nodes to all CPUs. For example, + node0 is for DDR5 DRAMs connected via DIMM, while node1 is for DDR4 + DRAMs connected via CXL. + + If unsure, say N. + +endmenu diff --git a/samples/damon/Makefile b/samples/damon/Makefile new file mode 100644 index 000000000..72f68cbf4 --- /dev/null +++ b/samples/damon/Makefile @@ -0,0 +1,5 @@ +# SPDX-License-Identifier: GPL-2.0 + +obj-$(CONFIG_SAMPLE_DAMON_WSSE) += wsse.o +obj-$(CONFIG_SAMPLE_DAMON_PRCL) += prcl.o +obj-$(CONFIG_SAMPLE_DAMON_MTIER) += mtier.o diff --git a/samples/damon/mtier.c b/samples/damon/mtier.c new file mode 100644 index 000000000..d1123ebbf --- /dev/null +++ b/samples/damon/mtier.c @@ -0,0 +1,255 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * memory tiering: migrate cold pages in node 0 and hot pages in node 1 to node + * 1 and node 0, respectively. Adjust the hotness/coldness threshold aiming + * resulting 99.6 % node 0 utilization ratio. + */ + +#define pr_fmt(fmt) "damon_sample_mtier: " fmt + +#include +#include +#include +#include + +#ifdef MODULE_PARAM_PREFIX +#undef MODULE_PARAM_PREFIX +#endif +#define MODULE_PARAM_PREFIX "damon_sample_mtier." + +static unsigned long node0_start_addr __read_mostly; +module_param(node0_start_addr, ulong, 0600); + +static unsigned long node0_end_addr __read_mostly; +module_param(node0_end_addr, ulong, 0600); + +static unsigned long node1_start_addr __read_mostly; +module_param(node1_start_addr, ulong, 0600); + +static unsigned long node1_end_addr __read_mostly; +module_param(node1_end_addr, ulong, 0600); + +static unsigned long node0_mem_used_bp __read_mostly = 9970; +module_param(node0_mem_used_bp, ulong, 0600); + +static unsigned long node0_mem_free_bp __read_mostly = 50; +module_param(node0_mem_free_bp, ulong, 0600); + +static int damon_sample_mtier_enable_store( + const char *val, const struct kernel_param *kp); + +static const struct kernel_param_ops enabled_param_ops = { + .set = damon_sample_mtier_enable_store, + .get = param_get_bool, +}; + +static bool enabled __read_mostly; +module_param_cb(enabled, &enabled_param_ops, &enabled, 0600); +MODULE_PARM_DESC(enabled, "Enable or disable DAMON_SAMPLE_MTIER"); + +static bool detect_node_addresses __read_mostly; +module_param(detect_node_addresses, bool, 0600); + +static struct damon_ctx *ctxs[2]; + +struct region_range { + phys_addr_t start; + phys_addr_t end; +}; + +static int nid_to_phys(int target_node, struct region_range *range) +{ + if (!node_online(target_node)) { + pr_err("NUMA node %d is not online\n", target_node); + return -EINVAL; + } + + range->start = PFN_PHYS(node_start_pfn(target_node)); + range->end = PFN_PHYS(node_end_pfn(target_node)); + + return 0; +} + +static struct damon_ctx *damon_sample_mtier_build_ctx(bool promote) +{ + struct damon_ctx *ctx; + struct damon_attrs attrs; + struct damon_target *target; + struct damos *scheme; + struct damos_quota_goal *quota_goal; + struct damos_filter *filter; + struct region_range addr; + struct damon_addr_range range; + int ret; + + ctx = damon_new_ctx(); + if (!ctx) + return NULL; + attrs = (struct damon_attrs) { + .sample_interval = 5 * USEC_PER_MSEC, + .aggr_interval = 100 * USEC_PER_MSEC, + .ops_update_interval = 60 * USEC_PER_MSEC * MSEC_PER_SEC, + .min_nr_regions = 10, + .max_nr_regions = 1000, + }; + + /* + * auto-tune sampling and aggregation interval aiming 4% DAMON-observed + * accesses ratio, keeping sampling interval in [5ms, 10s] range. + */ + attrs.intervals_goal = (struct damon_intervals_goal) { + .access_bp = 400, .aggrs = 3, + .min_sample_us = 5000, .max_sample_us = 10000000, + }; + if (damon_set_attrs(ctx, &attrs)) + goto free_out; + if (damon_select_ops(ctx, DAMON_OPS_PADDR)) + goto free_out; + + target = damon_new_target(); + if (!target) + goto free_out; + damon_add_target(ctx, target); + + if (detect_node_addresses) { + ret = promote ? nid_to_phys(1, &addr) : nid_to_phys(0, &addr); + if (ret) + goto free_out; + } else { + addr.start = promote ? node1_start_addr : node0_start_addr; + addr.end = promote ? node1_end_addr : node0_end_addr; + } + + if (addr.start >= addr.end) + goto free_out; + + range.start = addr.start; + range.end = addr.end; + + ret = damon_set_regions(target, &range, 1, DAMON_MIN_REGION_SZ); + if (ret) + goto free_out; + + scheme = damon_new_scheme( + /* access pattern */ + &(struct damos_access_pattern) { + .min_sz_region = PAGE_SIZE, + .max_sz_region = ULONG_MAX, + .min_nr_accesses = promote ? 1 : 0, + .max_nr_accesses = promote ? UINT_MAX : 0, + .min_age_region = 0, + .max_age_region = UINT_MAX}, + /* action */ + promote ? DAMOS_MIGRATE_HOT : DAMOS_MIGRATE_COLD, + 1000000, /* apply interval (1s) */ + &(struct damos_quota){ + /* 200 MiB per sec by most */ + .reset_interval = 1000, + .sz = 200 * 1024 * 1024, + /* ignore size of region when prioritizing */ + .weight_sz = 0, + .weight_nr_accesses = 100, + .weight_age = 100, + }, + &(struct damos_watermarks){}, + promote ? 0 : 1); /* migrate target node id */ + if (!scheme) + goto free_out; + damon_set_schemes(ctx, &scheme, 1); + /* zero target value causes division by zero in damos_quota_store() */ + if (!node0_mem_used_bp || !node0_mem_free_bp) + goto free_out; + quota_goal = damos_new_quota_goal( + promote ? DAMOS_QUOTA_NODE_MEM_USED_BP : + DAMOS_QUOTA_NODE_MEM_FREE_BP, + promote ? node0_mem_used_bp : node0_mem_free_bp); + if (!quota_goal) + goto free_out; + quota_goal->nid = 0; + damos_add_quota_goal(&scheme->quota, quota_goal); + filter = damos_new_filter(DAMOS_FILTER_TYPE_YOUNG, true, promote); + if (!filter) + goto free_out; + damos_add_filter(scheme, filter); + return ctx; +free_out: + damon_destroy_ctx(ctx); + return NULL; +} + +static int damon_sample_mtier_start(void) +{ + struct damon_ctx *ctx; + int err; + + ctx = damon_sample_mtier_build_ctx(true); + if (!ctx) + return -ENOMEM; + ctxs[0] = ctx; + ctx = damon_sample_mtier_build_ctx(false); + if (!ctx) { + damon_destroy_ctx(ctxs[0]); + return -ENOMEM; + } + ctxs[1] = ctx; + err = damon_start(ctxs, 2, true); + if (!err) + return 0; + + damon_destroy_ctx(ctxs[0]); + damon_destroy_ctx(ctxs[1]); + return err; +} + +static void damon_sample_mtier_stop(void) +{ + damon_stop(ctxs, 2); + damon_destroy_ctx(ctxs[0]); + damon_destroy_ctx(ctxs[1]); +} + +static int damon_sample_mtier_enable_store( + const char *val, const struct kernel_param *kp) +{ + bool is_enabled = enabled; + int err; + + err = kstrtobool(val, &enabled); + if (err) + return err; + + if (enabled == is_enabled) + return 0; + + if (!damon_initialized()) + return 0; + + if (enabled) { + err = damon_sample_mtier_start(); + if (err) + enabled = false; + return err; + } + damon_sample_mtier_stop(); + return 0; +} + +static int __init damon_sample_mtier_init(void) +{ + int err = 0; + + if (!damon_initialized()) { + if (enabled) + enabled = false; + return -ENOMEM; + } + + if (enabled) { + err = damon_sample_mtier_start(); + if (err) + enabled = false; + } + return 0; +} + +module_init(damon_sample_mtier_init); diff --git a/samples/damon/prcl.c b/samples/damon/prcl.c new file mode 100644 index 000000000..842099bd6 --- /dev/null +++ b/samples/damon/prcl.c @@ -0,0 +1,174 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * proactive reclamation: monitor access pattern of a given process, find + * regions that seems not accessed, and proactively page out the regions. + */ + +#define pr_fmt(fmt) "damon_sample_prcl: " fmt + +#include +#include +#include +#include + +#ifdef MODULE_PARAM_PREFIX +#undef MODULE_PARAM_PREFIX +#endif +#define MODULE_PARAM_PREFIX "damon_sample_prcl." + +static int target_pid __read_mostly; +module_param(target_pid, int, 0600); + +static int damon_sample_prcl_enable_store( + const char *val, const struct kernel_param *kp); + +static const struct kernel_param_ops enabled_param_ops = { + .set = damon_sample_prcl_enable_store, + .get = param_get_bool, +}; + +static bool enabled __read_mostly; +module_param_cb(enabled, &enabled_param_ops, &enabled, 0600); +MODULE_PARM_DESC(enabled, "Enable or disable DAMON_SAMPLE_PRCL"); + +static struct damon_ctx *ctx; +static struct pid *target_pidp; + +static int damon_sample_prcl_repeat_call_fn(void *data) +{ + struct damon_ctx *c = data; + 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 struct damon_call_control repeat_call_control = { + .fn = damon_sample_prcl_repeat_call_fn, + .repeat = true, +}; + +static int damon_sample_prcl_start(void) +{ + struct damon_target *target; + struct damos *scheme; + int err; + + pr_info("start\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; + + scheme = damon_new_scheme( + &(struct damos_access_pattern) { + .min_sz_region = PAGE_SIZE, + .max_sz_region = ULONG_MAX, + .min_nr_accesses = 0, + .max_nr_accesses = 0, + .min_age_region = 50, + .max_age_region = UINT_MAX}, + DAMOS_PAGEOUT, + 0, + &(struct damos_quota){}, + &(struct damos_watermarks){}, + NUMA_NO_NODE); + if (!scheme) { + damon_destroy_ctx(ctx); + return -ENOMEM; + } + damon_set_schemes(ctx, &scheme, 1); + + err = damon_start(&ctx, 1, true); + if (err) { + damon_destroy_ctx(ctx); + return err; + } + + repeat_call_control.data = ctx; + err = damon_call(ctx, &repeat_call_control); + if (err) + damon_destroy_ctx(ctx); + return err; +} + +static void damon_sample_prcl_stop(void) +{ + pr_info("stop\n"); + if (ctx) { + damon_stop(&ctx, 1); + damon_destroy_ctx(ctx); + } +} + +static int damon_sample_prcl_enable_store( + const char *val, const struct kernel_param *kp) +{ + bool is_enabled = enabled; + int err; + + err = kstrtobool(val, &enabled); + if (err) + return err; + + if (enabled == is_enabled) + return 0; + + if (!damon_initialized()) + return 0; + + if (enabled) { + err = damon_sample_prcl_start(); + if (err) + enabled = false; + return err; + } + damon_sample_prcl_stop(); + return 0; +} + +static int __init damon_sample_prcl_init(void) +{ + int err = 0; + + if (!damon_initialized()) { + if (enabled) + enabled = false; + return -ENOMEM; + } + + if (enabled) { + err = damon_sample_prcl_start(); + if (err) + enabled = false; + } + return 0; +} + +module_init(damon_sample_prcl_init); diff --git a/samples/damon/wsse.c b/samples/damon/wsse.c new file mode 100644 index 000000000..37fd5da20 --- /dev/null +++ b/samples/damon/wsse.c @@ -0,0 +1,154 @@ +// 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 + +#ifdef MODULE_PARAM_PREFIX +#undef MODULE_PARAM_PREFIX +#endif +#define MODULE_PARAM_PREFIX "damon_sample_wsse." + +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 enabled_param_ops = { + .set = damon_sample_wsse_enable_store, + .get = param_get_bool, +}; + +static bool enabled __read_mostly; +module_param_cb(enabled, &enabled_param_ops, &enabled, 0600); +MODULE_PARM_DESC(enabled, "Enable or disable DAMON_SAMPLE_WSSE"); + +static struct damon_ctx *ctx; +static struct pid *target_pidp; + +static int damon_sample_wsse_repeat_call_fn(void *data) +{ + struct damon_ctx *c = data; + 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 struct damon_call_control repeat_call_control = { + .fn = damon_sample_wsse_repeat_call_fn, + .repeat = true, +}; + +static int damon_sample_wsse_start(void) +{ + struct damon_target *target; + int err; + + pr_info("start\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; + + err = damon_start(&ctx, 1, true); + if (err) { + damon_destroy_ctx(ctx); + return err; + } + repeat_call_control.data = ctx; + err = damon_call(ctx, &repeat_call_control); + if (err) + damon_destroy_ctx(ctx); + return err; +} + +static void damon_sample_wsse_stop(void) +{ + pr_info("stop\n"); + if (ctx) { + damon_stop(&ctx, 1); + damon_destroy_ctx(ctx); + } +} + +static int damon_sample_wsse_enable_store( + const char *val, const struct kernel_param *kp) +{ + bool is_enabled = enabled; + int err; + + err = kstrtobool(val, &enabled); + if (err) + return err; + + if (enabled == is_enabled) + return 0; + + if (!damon_initialized()) + return 0; + + if (enabled) { + err = damon_sample_wsse_start(); + if (err) + enabled = false; + return err; + } + damon_sample_wsse_stop(); + return 0; +} + +static int __init damon_sample_wsse_init(void) +{ + int err = 0; + + if (!damon_initialized()) { + err = -ENOMEM; + if (enabled) + enabled = false; + } + + if (enabled) { + err = damon_sample_wsse_start(); + if (err) + enabled = false; + } + return err; +} + +module_init(damon_sample_wsse_init); -- cgit v1.3.1