Revision 944293bcee92acb1cfbbd315f833b4384bfd35fa authored by Linus Torvalds on 18 June 2021, 17:42:36 UTC, committed by Linus Torvalds on 18 June 2021, 17:42:36 UTC
Pull power management fix from Rafael Wysocki: "Remove recently added frequency invariance support from the CPPC cpufreq driver, because it has turned out to be problematic and it cannot be fixed properly on time for 5.13 (Viresh Kumar)" * tag 'pm-5.13-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: Revert "cpufreq: CPPC: Add support for frequency invariance"
watch_test.c
// SPDX-License-Identifier: GPL-2.0
/* Use watch_queue API to watch for notifications.
*
* Copyright (C) 2020 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*/
#define _GNU_SOURCE
#include <stdbool.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <signal.h>
#include <unistd.h>
#include <errno.h>
#include <sys/ioctl.h>
#include <limits.h>
#include <linux/watch_queue.h>
#include <linux/unistd.h>
#include <linux/keyctl.h>
#ifndef KEYCTL_WATCH_KEY
#define KEYCTL_WATCH_KEY -1
#endif
#ifndef __NR_keyctl
#define __NR_keyctl -1
#endif
#define BUF_SIZE 256
static long keyctl_watch_key(int key, int watch_fd, int watch_id)
{
return syscall(__NR_keyctl, KEYCTL_WATCH_KEY, key, watch_fd, watch_id);
}
static const char *key_subtypes[256] = {
[NOTIFY_KEY_INSTANTIATED] = "instantiated",
[NOTIFY_KEY_UPDATED] = "updated",
[NOTIFY_KEY_LINKED] = "linked",
[NOTIFY_KEY_UNLINKED] = "unlinked",
[NOTIFY_KEY_CLEARED] = "cleared",
[NOTIFY_KEY_REVOKED] = "revoked",
[NOTIFY_KEY_INVALIDATED] = "invalidated",
[NOTIFY_KEY_SETATTR] = "setattr",
};
static void saw_key_change(struct watch_notification *n, size_t len)
{
struct key_notification *k = (struct key_notification *)n;
if (len != sizeof(struct key_notification)) {
fprintf(stderr, "Incorrect key message length\n");
return;
}
printf("KEY %08x change=%u[%s] aux=%u\n",
k->key_id, n->subtype, key_subtypes[n->subtype], k->aux);
}
/*
* Consume and display events.
*/
static void consumer(int fd)
{
unsigned char buffer[433], *p, *end;
union {
struct watch_notification n;
unsigned char buf1[128];
} n;
ssize_t buf_len;
for (;;) {
buf_len = read(fd, buffer, sizeof(buffer));
if (buf_len == -1) {
perror("read");
exit(1);
}
if (buf_len == 0) {
printf("-- END --\n");
return;
}
if (buf_len > sizeof(buffer)) {
fprintf(stderr, "Read buffer overrun: %zd\n", buf_len);
return;
}
printf("read() = %zd\n", buf_len);
p = buffer;
end = buffer + buf_len;
while (p < end) {
size_t largest, len;
largest = end - p;
if (largest > 128)
largest = 128;
if (largest < sizeof(struct watch_notification)) {
fprintf(stderr, "Short message header: %zu\n", largest);
return;
}
memcpy(&n, p, largest);
printf("NOTIFY[%03zx]: ty=%06x sy=%02x i=%08x\n",
p - buffer, n.n.type, n.n.subtype, n.n.info);
len = n.n.info & WATCH_INFO_LENGTH;
if (len < sizeof(n.n) || len > largest) {
fprintf(stderr, "Bad message length: %zu/%zu\n", len, largest);
exit(1);
}
switch (n.n.type) {
case WATCH_TYPE_META:
switch (n.n.subtype) {
case WATCH_META_REMOVAL_NOTIFICATION:
printf("REMOVAL of watchpoint %08x\n",
(n.n.info & WATCH_INFO_ID) >>
WATCH_INFO_ID__SHIFT);
break;
case WATCH_META_LOSS_NOTIFICATION:
printf("-- LOSS --\n");
break;
default:
printf("other meta record\n");
break;
}
break;
case WATCH_TYPE_KEY_NOTIFY:
saw_key_change(&n.n, len);
break;
default:
printf("other type\n");
break;
}
p += len;
}
}
}
static struct watch_notification_filter filter = {
.nr_filters = 1,
.filters = {
[0] = {
.type = WATCH_TYPE_KEY_NOTIFY,
.subtype_filter[0] = UINT_MAX,
},
},
};
int main(int argc, char **argv)
{
int pipefd[2], fd;
if (pipe2(pipefd, O_NOTIFICATION_PIPE) == -1) {
perror("pipe2");
exit(1);
}
fd = pipefd[0];
if (ioctl(fd, IOC_WATCH_QUEUE_SET_SIZE, BUF_SIZE) == -1) {
perror("watch_queue(size)");
exit(1);
}
if (ioctl(fd, IOC_WATCH_QUEUE_SET_FILTER, &filter) == -1) {
perror("watch_queue(filter)");
exit(1);
}
if (keyctl_watch_key(KEY_SPEC_SESSION_KEYRING, fd, 0x01) == -1) {
perror("keyctl");
exit(1);
}
if (keyctl_watch_key(KEY_SPEC_USER_KEYRING, fd, 0x02) == -1) {
perror("keyctl");
exit(1);
}
consumer(fd);
exit(0);
}
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