Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752516AbaKUXay (ORCPT ); Fri, 21 Nov 2014 18:30:54 -0500 Received: from mail-ob0-f170.google.com ([209.85.214.170]:59906 "EHLO mail-ob0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752172AbaKUXaw (ORCPT ); Fri, 21 Nov 2014 18:30:52 -0500 MIME-Version: 1.0 In-Reply-To: <1416599058-13836-2-git-send-email-john.stultz@linaro.org> References: <1416599058-13836-1-git-send-email-john.stultz@linaro.org> <1416599058-13836-2-git-send-email-john.stultz@linaro.org> Date: Fri, 21 Nov 2014 15:30:51 -0800 X-Google-Sender-Auth: h9IeoLmCCQcoZRVkKQwdYfNxyTA Message-ID: Subject: Re: [PATCH 01/12] time: Rename udelay_test.c to test_udelay.c From: Kees Cook To: John Stultz Cc: lkml , Greg KH , Stephen Rothwell , Thomas Gleixner , Ingo Molnar , Linux-Next , David Riley Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Nov 21, 2014 at 11:44 AM, John Stultz wrote: > Kees requested that this test module be renamed for consistency sake, > so this patch renames the udelay_test.c file (recently added to > tip/timers/core for 3.17) to test_udelay.c > > Cc: Kees Cook > Cc: Greg KH > Cc: Stephen Rothwell > Cc: Thomas Gleixner > Cc: Ingo Molnar > Cc: Linux-Next > Cc: David Riley > Signed-off-by: John Stultz Reviewed-by: Kees Cook Yes please! :) -Kees > --- > kernel/time/Makefile | 2 +- > kernel/time/test_udelay.c | 168 ++++++++++++++++++++++++++++++++++++++++++++++ > kernel/time/udelay_test.c | 168 ---------------------------------------------- > 3 files changed, 169 insertions(+), 169 deletions(-) > create mode 100644 kernel/time/test_udelay.c > delete mode 100644 kernel/time/udelay_test.c > > diff --git a/kernel/time/Makefile b/kernel/time/Makefile > index 7347426..f622cf2 100644 > --- a/kernel/time/Makefile > +++ b/kernel/time/Makefile > @@ -13,7 +13,7 @@ obj-$(CONFIG_TICK_ONESHOT) += tick-oneshot.o > obj-$(CONFIG_TICK_ONESHOT) += tick-sched.o > obj-$(CONFIG_TIMER_STATS) += timer_stats.o > obj-$(CONFIG_DEBUG_FS) += timekeeping_debug.o > -obj-$(CONFIG_TEST_UDELAY) += udelay_test.o > +obj-$(CONFIG_TEST_UDELAY) += test_udelay.o > > $(obj)/time.o: $(obj)/timeconst.h > > diff --git a/kernel/time/test_udelay.c b/kernel/time/test_udelay.c > new file mode 100644 > index 0000000..e622ba3 > --- /dev/null > +++ b/kernel/time/test_udelay.c > @@ -0,0 +1,168 @@ > +/* > + * udelay() test kernel module > + * > + * Test is executed by writing and reading to /sys/kernel/debug/udelay_test > + * Tests are configured by writing: USECS ITERATIONS > + * Tests are executed by reading from the same file. > + * Specifying usecs of 0 or negative values will run multiples tests. > + * > + * Copyright (C) 2014 Google, Inc. > + * > + * This software is licensed under the terms of the GNU General Public > + * License version 2, as published by the Free Software Foundation, and > + * may be copied, distributed, and modified under those terms. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + */ > + > +#include > +#include > +#include > +#include > +#include > + > +#define DEFAULT_ITERATIONS 100 > + > +#define DEBUGFS_FILENAME "udelay_test" > + > +static DEFINE_MUTEX(udelay_test_lock); > +static struct dentry *udelay_test_debugfs_file; > +static int udelay_test_usecs; > +static int udelay_test_iterations = DEFAULT_ITERATIONS; > + > +static int udelay_test_single(struct seq_file *s, int usecs, uint32_t iters) > +{ > + int min = 0, max = 0, fail_count = 0; > + uint64_t sum = 0; > + uint64_t avg; > + int i; > + /* Allow udelay to be up to 0.5% fast */ > + int allowed_error_ns = usecs * 5; > + > + for (i = 0; i < iters; ++i) { > + struct timespec ts1, ts2; > + int time_passed; > + > + ktime_get_ts(&ts1); > + udelay(usecs); > + ktime_get_ts(&ts2); > + time_passed = timespec_to_ns(&ts2) - timespec_to_ns(&ts1); > + > + if (i == 0 || time_passed < min) > + min = time_passed; > + if (i == 0 || time_passed > max) > + max = time_passed; > + if ((time_passed + allowed_error_ns) / 1000 < usecs) > + ++fail_count; > + WARN_ON(time_passed < 0); > + sum += time_passed; > + } > + > + avg = sum; > + do_div(avg, iters); > + seq_printf(s, "%d usecs x %d: exp=%d allowed=%d min=%d avg=%lld max=%d", > + usecs, iters, usecs * 1000, > + (usecs * 1000) - allowed_error_ns, min, avg, max); > + if (fail_count) > + seq_printf(s, " FAIL=%d", fail_count); > + seq_puts(s, "\n"); > + > + return 0; > +} > + > +static int udelay_test_show(struct seq_file *s, void *v) > +{ > + int usecs; > + int iters; > + int ret = 0; > + > + mutex_lock(&udelay_test_lock); > + usecs = udelay_test_usecs; > + iters = udelay_test_iterations; > + mutex_unlock(&udelay_test_lock); > + > + if (usecs > 0 && iters > 0) { > + return udelay_test_single(s, usecs, iters); > + } else if (usecs == 0) { > + struct timespec ts; > + > + ktime_get_ts(&ts); > + seq_printf(s, "udelay() test (lpj=%ld kt=%ld.%09ld)\n", > + loops_per_jiffy, ts.tv_sec, ts.tv_nsec); > + seq_puts(s, "usage:\n"); > + seq_puts(s, "echo USECS [ITERS] > " DEBUGFS_FILENAME "\n"); > + seq_puts(s, "cat " DEBUGFS_FILENAME "\n"); > + } > + > + return ret; > +} > + > +static int udelay_test_open(struct inode *inode, struct file *file) > +{ > + return single_open(file, udelay_test_show, inode->i_private); > +} > + > +static ssize_t udelay_test_write(struct file *file, const char __user *buf, > + size_t count, loff_t *pos) > +{ > + char lbuf[32]; > + int ret; > + int usecs; > + int iters; > + > + if (count >= sizeof(lbuf)) > + return -EINVAL; > + > + if (copy_from_user(lbuf, buf, count)) > + return -EFAULT; > + lbuf[count] = '\0'; > + > + ret = sscanf(lbuf, "%d %d", &usecs, &iters); > + if (ret < 1) > + return -EINVAL; > + else if (ret < 2) > + iters = DEFAULT_ITERATIONS; > + > + mutex_lock(&udelay_test_lock); > + udelay_test_usecs = usecs; > + udelay_test_iterations = iters; > + mutex_unlock(&udelay_test_lock); > + > + return count; > +} > + > +static const struct file_operations udelay_test_debugfs_ops = { > + .owner = THIS_MODULE, > + .open = udelay_test_open, > + .read = seq_read, > + .write = udelay_test_write, > + .llseek = seq_lseek, > + .release = single_release, > +}; > + > +static int __init udelay_test_init(void) > +{ > + mutex_lock(&udelay_test_lock); > + udelay_test_debugfs_file = debugfs_create_file(DEBUGFS_FILENAME, > + S_IRUSR, NULL, NULL, &udelay_test_debugfs_ops); > + mutex_unlock(&udelay_test_lock); > + > + return 0; > +} > + > +module_init(udelay_test_init); > + > +static void __exit udelay_test_exit(void) > +{ > + mutex_lock(&udelay_test_lock); > + debugfs_remove(udelay_test_debugfs_file); > + mutex_unlock(&udelay_test_lock); > +} > + > +module_exit(udelay_test_exit); > + > +MODULE_AUTHOR("David Riley "); > +MODULE_LICENSE("GPL"); > diff --git a/kernel/time/udelay_test.c b/kernel/time/udelay_test.c > deleted file mode 100644 > index e622ba3..0000000 > --- a/kernel/time/udelay_test.c > +++ /dev/null > @@ -1,168 +0,0 @@ > -/* > - * udelay() test kernel module > - * > - * Test is executed by writing and reading to /sys/kernel/debug/udelay_test > - * Tests are configured by writing: USECS ITERATIONS > - * Tests are executed by reading from the same file. > - * Specifying usecs of 0 or negative values will run multiples tests. > - * > - * Copyright (C) 2014 Google, Inc. > - * > - * This software is licensed under the terms of the GNU General Public > - * License version 2, as published by the Free Software Foundation, and > - * may be copied, distributed, and modified under those terms. > - * > - * This program is distributed in the hope that it will be useful, > - * but WITHOUT ANY WARRANTY; without even the implied warranty of > - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > - * GNU General Public License for more details. > - */ > - > -#include > -#include > -#include > -#include > -#include > - > -#define DEFAULT_ITERATIONS 100 > - > -#define DEBUGFS_FILENAME "udelay_test" > - > -static DEFINE_MUTEX(udelay_test_lock); > -static struct dentry *udelay_test_debugfs_file; > -static int udelay_test_usecs; > -static int udelay_test_iterations = DEFAULT_ITERATIONS; > - > -static int udelay_test_single(struct seq_file *s, int usecs, uint32_t iters) > -{ > - int min = 0, max = 0, fail_count = 0; > - uint64_t sum = 0; > - uint64_t avg; > - int i; > - /* Allow udelay to be up to 0.5% fast */ > - int allowed_error_ns = usecs * 5; > - > - for (i = 0; i < iters; ++i) { > - struct timespec ts1, ts2; > - int time_passed; > - > - ktime_get_ts(&ts1); > - udelay(usecs); > - ktime_get_ts(&ts2); > - time_passed = timespec_to_ns(&ts2) - timespec_to_ns(&ts1); > - > - if (i == 0 || time_passed < min) > - min = time_passed; > - if (i == 0 || time_passed > max) > - max = time_passed; > - if ((time_passed + allowed_error_ns) / 1000 < usecs) > - ++fail_count; > - WARN_ON(time_passed < 0); > - sum += time_passed; > - } > - > - avg = sum; > - do_div(avg, iters); > - seq_printf(s, "%d usecs x %d: exp=%d allowed=%d min=%d avg=%lld max=%d", > - usecs, iters, usecs * 1000, > - (usecs * 1000) - allowed_error_ns, min, avg, max); > - if (fail_count) > - seq_printf(s, " FAIL=%d", fail_count); > - seq_puts(s, "\n"); > - > - return 0; > -} > - > -static int udelay_test_show(struct seq_file *s, void *v) > -{ > - int usecs; > - int iters; > - int ret = 0; > - > - mutex_lock(&udelay_test_lock); > - usecs = udelay_test_usecs; > - iters = udelay_test_iterations; > - mutex_unlock(&udelay_test_lock); > - > - if (usecs > 0 && iters > 0) { > - return udelay_test_single(s, usecs, iters); > - } else if (usecs == 0) { > - struct timespec ts; > - > - ktime_get_ts(&ts); > - seq_printf(s, "udelay() test (lpj=%ld kt=%ld.%09ld)\n", > - loops_per_jiffy, ts.tv_sec, ts.tv_nsec); > - seq_puts(s, "usage:\n"); > - seq_puts(s, "echo USECS [ITERS] > " DEBUGFS_FILENAME "\n"); > - seq_puts(s, "cat " DEBUGFS_FILENAME "\n"); > - } > - > - return ret; > -} > - > -static int udelay_test_open(struct inode *inode, struct file *file) > -{ > - return single_open(file, udelay_test_show, inode->i_private); > -} > - > -static ssize_t udelay_test_write(struct file *file, const char __user *buf, > - size_t count, loff_t *pos) > -{ > - char lbuf[32]; > - int ret; > - int usecs; > - int iters; > - > - if (count >= sizeof(lbuf)) > - return -EINVAL; > - > - if (copy_from_user(lbuf, buf, count)) > - return -EFAULT; > - lbuf[count] = '\0'; > - > - ret = sscanf(lbuf, "%d %d", &usecs, &iters); > - if (ret < 1) > - return -EINVAL; > - else if (ret < 2) > - iters = DEFAULT_ITERATIONS; > - > - mutex_lock(&udelay_test_lock); > - udelay_test_usecs = usecs; > - udelay_test_iterations = iters; > - mutex_unlock(&udelay_test_lock); > - > - return count; > -} > - > -static const struct file_operations udelay_test_debugfs_ops = { > - .owner = THIS_MODULE, > - .open = udelay_test_open, > - .read = seq_read, > - .write = udelay_test_write, > - .llseek = seq_lseek, > - .release = single_release, > -}; > - > -static int __init udelay_test_init(void) > -{ > - mutex_lock(&udelay_test_lock); > - udelay_test_debugfs_file = debugfs_create_file(DEBUGFS_FILENAME, > - S_IRUSR, NULL, NULL, &udelay_test_debugfs_ops); > - mutex_unlock(&udelay_test_lock); > - > - return 0; > -} > - > -module_init(udelay_test_init); > - > -static void __exit udelay_test_exit(void) > -{ > - mutex_lock(&udelay_test_lock); > - debugfs_remove(udelay_test_debugfs_file); > - mutex_unlock(&udelay_test_lock); > -} > - > -module_exit(udelay_test_exit); > - > -MODULE_AUTHOR("David Riley "); > -MODULE_LICENSE("GPL"); > -- > 1.9.1 > -- Kees Cook Chrome OS Security -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/