From 4352b8aee98005853aa63f57d6377282de17a33f Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 23 Aug 2026 13:28:57 -0700 Subject: Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ... --- lib/plist.c | 311 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 311 insertions(+) create mode 100644 lib/plist.c (limited to 'lib/plist.c') diff --git a/lib/plist.c b/lib/plist.c new file mode 100644 index 000000000..a5bef38ad --- /dev/null +++ b/lib/plist.c @@ -0,0 +1,311 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * lib/plist.c + * + * Descending-priority-sorted double-linked list + * + * (C) 2002-2003 Intel Corp + * Inaky Perez-Gonzalez . + * + * 2001-2005 (c) MontaVista Software, Inc. + * Daniel Walker + * + * (C) 2005 Linutronix GmbH, Thomas Gleixner + * + * Simplifications of the original code by + * Oleg Nesterov + * + * Based on simple lists (include/linux/list.h). + * + * This file contains the add / del functions which are considered to + * be too large to inline. See include/linux/plist.h for further + * information. + */ + +#include +#include + +#ifdef CONFIG_DEBUG_PLIST + +static struct plist_head test_head; + +static void plist_check_prev_next(struct list_head *t, struct list_head *p, + struct list_head *n) +{ + WARN(n->prev != p || p->next != n, + "top: %p, n: %p, p: %p\n" + "prev: %p, n: %p, p: %p\n" + "next: %p, n: %p, p: %p\n", + t, t->next, t->prev, + p, p->next, p->prev, + n, n->next, n->prev); +} + +static void plist_check_list(struct list_head *top) +{ + struct list_head *prev = top, *next = top->next; + + plist_check_prev_next(top, prev, next); + while (next != top) { + prev = next; + next = prev->next; + plist_check_prev_next(top, prev, next); + } +} + +static void plist_check_head(struct plist_head *head) +{ + if (!plist_head_empty(head)) + plist_check_list(&plist_first(head)->prio_list); + plist_check_list(&head->node_list); +} + +#else +# define plist_check_head(h) do { } while (0) +#endif + +/** + * plist_add - add @node to @head + * + * @node: &struct plist_node pointer + * @head: &struct plist_head pointer + */ +void plist_add(struct plist_node *node, struct plist_head *head) +{ + struct plist_node *first, *iter, *prev = NULL, *last, *reverse_iter; + struct list_head *node_next = &head->node_list; + + plist_check_head(head); + WARN_ON(!plist_node_empty(node)); + WARN_ON(!list_empty(&node->prio_list)); + + if (plist_head_empty(head)) + goto ins_node; + + first = iter = plist_first(head); + last = reverse_iter = list_entry(first->prio_list.prev, struct plist_node, prio_list); + + do { + if (node->prio < iter->prio) { + node_next = &iter->node_list; + break; + } else if (node->prio >= reverse_iter->prio) { + prev = reverse_iter; + iter = list_entry(reverse_iter->prio_list.next, + struct plist_node, prio_list); + if (likely(reverse_iter != last)) + node_next = &iter->node_list; + break; + } + + prev = iter; + iter = list_entry(iter->prio_list.next, + struct plist_node, prio_list); + reverse_iter = list_entry(reverse_iter->prio_list.prev, + struct plist_node, prio_list); + } while (iter != first); + + if (!prev || prev->prio != node->prio) + list_add_tail(&node->prio_list, &iter->prio_list); +ins_node: + list_add_tail(&node->node_list, node_next); + + plist_check_head(head); +} + +/** + * plist_del - Remove a @node from plist. + * + * @node: &struct plist_node pointer - entry to be removed + * @head: &struct plist_head pointer - list head + */ +void plist_del(struct plist_node *node, struct plist_head *head) +{ + plist_check_head(head); + + if (!list_empty(&node->prio_list)) { + if (node->node_list.next != &head->node_list) { + struct plist_node *next; + + next = list_entry(node->node_list.next, + struct plist_node, node_list); + + /* add the next plist_node into prio_list */ + if (list_empty(&next->prio_list)) + list_add(&next->prio_list, &node->prio_list); + } + list_del_init(&node->prio_list); + } + + list_del_init(&node->node_list); + + plist_check_head(head); +} + +/** + * plist_requeue - Requeue @node at end of same-prio entries. + * + * This is essentially an optimized plist_del() followed by + * plist_add(). It moves an entry already in the plist to + * after any other same-priority entries. + * + * @node: &struct plist_node pointer - entry to be moved + * @head: &struct plist_head pointer - list head + */ +void plist_requeue(struct plist_node *node, struct plist_head *head) +{ + struct plist_node *iter; + struct list_head *node_next = &head->node_list; + + plist_check_head(head); + BUG_ON(plist_head_empty(head)); + BUG_ON(plist_node_empty(node)); + + if (node == plist_last(head)) + return; + + iter = plist_next(node); + + if (node->prio != iter->prio) + return; + + plist_del(node, head); + + /* + * After plist_del(), iter is the replacement of the node. If the node + * was on prio_list, take shortcut to find node_next instead of looping. + */ + if (!list_empty(&iter->prio_list)) { + iter = list_entry(iter->prio_list.next, struct plist_node, + prio_list); + node_next = &iter->node_list; + goto queue; + } + + plist_for_each_continue(iter, head) { + if (node->prio != iter->prio) { + node_next = &iter->node_list; + break; + } + } +queue: + list_add_tail(&node->node_list, node_next); + + plist_check_head(head); +} + +#ifdef CONFIG_DEBUG_PLIST +#include +#include +#include +#include + +static struct plist_node __initdata test_node[241]; + +static void __init plist_test_check(int nr_expect) +{ + struct plist_node *first, *prio_pos, *node_pos; + + if (plist_head_empty(&test_head)) { + BUG_ON(nr_expect != 0); + return; + } + + prio_pos = first = plist_first(&test_head); + plist_for_each(node_pos, &test_head) { + if (nr_expect-- < 0) + break; + if (node_pos == first) + continue; + if (node_pos->prio == prio_pos->prio) { + BUG_ON(!list_empty(&node_pos->prio_list)); + continue; + } + + BUG_ON(prio_pos->prio > node_pos->prio); + BUG_ON(prio_pos->prio_list.next != &node_pos->prio_list); + prio_pos = node_pos; + } + + BUG_ON(nr_expect != 0); + BUG_ON(prio_pos->prio_list.next != &first->prio_list); +} + +static void __init plist_test_requeue(struct plist_node *node) +{ + plist_requeue(node, &test_head); + + if (node != plist_last(&test_head)) + BUG_ON(node->prio == plist_next(node)->prio); +} + +static int __init plist_test(void) +{ + int nr_expect = 0, i, loop; + unsigned int r = local_clock(); + + printk(KERN_DEBUG "start plist test\n"); + plist_head_init(&test_head); + for (i = 0; i < ARRAY_SIZE(test_node); i++) + plist_node_init(test_node + i, 0); + + for (loop = 0; loop < 1000; loop++) { + r = r * 193939 % 47629; + i = r % ARRAY_SIZE(test_node); + if (plist_node_empty(test_node + i)) { + r = r * 193939 % 47629; + test_node[i].prio = r % 99; + plist_add(test_node + i, &test_head); + nr_expect++; + } else { + plist_del(test_node + i, &test_head); + nr_expect--; + } + plist_test_check(nr_expect); + if (!plist_node_empty(test_node + i)) { + plist_test_requeue(test_node + i); + plist_test_check(nr_expect); + } + } + + for (i = 0; i < ARRAY_SIZE(test_node); i++) { + if (plist_node_empty(test_node + i)) + continue; + plist_del(test_node + i, &test_head); + nr_expect--; + plist_test_check(nr_expect); + } + + printk(KERN_DEBUG "end plist test\n"); + + /* Worst case test for plist_add() */ + unsigned int test_data[241]; + + for (i = 0; i < ARRAY_SIZE(test_data); i++) + test_data[i] = i; + + ktime_t start, end, time_elapsed = 0; + + plist_head_init(&test_head); + + for (i = 0; i < ARRAY_SIZE(test_node); i++) { + plist_node_init(test_node + i, 0); + test_node[i].prio = test_data[i]; + } + + for (i = 0; i < ARRAY_SIZE(test_node); i++) { + if (plist_node_empty(test_node + i)) { + start = ktime_get(); + plist_add(test_node + i, &test_head); + end = ktime_get(); + time_elapsed += (end - start); + } + } + + pr_debug("plist_add worst case test time elapsed %lld\n", time_elapsed); + return 0; +} + +module_init(plist_test); + +#endif -- cgit v1.3.1