Centos-kernel-stream-9/kernel/tsacct.c

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treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157 Based on 3 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version 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 this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version [author] [kishon] [vijay] [abraham] [i] [kishon]@[ti] [com] 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 this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version [author] [graeme] [gregory] [gg]@[slimlogic] [co] [uk] [author] [kishon] [vijay] [abraham] [i] [kishon]@[ti] [com] [based] [on] [twl6030]_[usb] [c] [author] [hema] [hk] [hemahk]@[ti] [com] 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 extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 1105 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Richard Fontana <rfontana@redhat.com> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070033.202006027@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-27 06:55:06 +00:00
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* tsacct.c - System accounting over taskstats interface
*
* Copyright (C) Jay Lan, <jlan@sgi.com>
*/
#include <linux/kernel.h>
#include <linux/sched/signal.h>
#include <linux/sched/mm.h>
#include <linux/sched/cputime.h>
#include <linux/tsacct_kern.h>
#include <linux/acct.h>
#include <linux/jiffies.h>
#include <linux/mm.h>
/*
* fill in basic accounting fields
*/
void bacct_add_tsk(struct user_namespace *user_ns,
struct pid_namespace *pid_ns,
struct taskstats *stats, struct task_struct *tsk)
{
const struct cred *tcred;
u64 utime, stime, utimescaled, stimescaled;
taskstats: version 12 with thread group and exe info Bugzilla: https://bugzilla.redhat.com/2160210 commit 0e0af57e0e91b304f36b7d1dba859e3c04094273 Author: Dr. Thomas Orgis <thomas.orgis@uni-hamburg.de> Date: Fri Apr 29 14:38:03 2022 -0700 taskstats: version 12 with thread group and exe info The task exit struct needs some crucial information to be able to provide an enhanced version of process and thread accounting. This change provides: 1. ac_tgid in additon to ac_pid 2. thread group execution walltime in ac_tgetime 3. flag AGROUP in ac_flag to indicate the last task in a thread group / process 4. device ID and inode of task's /proc/self/exe in ac_exe_dev and ac_exe_inode 5. tools/accounting/procacct as demonstrator When a task exits, taskstats are reported to userspace including the task's pid and ppid, but without the id of the thread group this task is part of. Without the tgid, the stats of single tasks cannot be correlated to each other as a thread group (process). The taskstats documentation suggests that on process exit a data set consisting of accumulated stats for the whole group is produced. But such an additional set of stats is only produced for actually multithreaded processes, not groups that had only one thread, and also those stats only contain data about delay accounting and not the more basic information about CPU and memory resource usage. Adding the AGROUP flag to be set when the last task of a group exited enables determination of process end also for single-threaded processes. My applicaton basically does enhanced process accounting with summed cputime, biggest maxrss, tasks per process. The data is not available with the traditional BSD process accounting (which is not designed to be extensible) and the taskstats interface allows more efficient on-the-fly grouping and summing of the stats, anyway, without intermediate disk writes. Furthermore, I do carry statistics on which exact program binary is used how often with associated resources, getting a picture on how important which parts of a collection of installed scientific software in different versions are, and how well they put load on the machine. This is enabled by providing information on /proc/self/exe for each task. I assume the two 64-bit fields for device ID and inode are more appropriate than the possibly large resolved path to keep the data volume down. Add the tgid to the stats to complete task identification, the flag AGROUP to mark the last task of a group, the group wallclock time, and inode-based identification of the associated executable file. Add tools/accounting/procacct.c as a simplified fork of getdelays.c to demonstrate process and thread accounting. [thomas.orgis@uni-hamburg.de: fix version number in comment] Link: https://lkml.kernel.org/r/20220405003601.7a5f6008@plasteblaster Link: https://lkml.kernel.org/r/20220331004106.64e5616b@plasteblaster Signed-off-by: Dr. Thomas Orgis <thomas.orgis@uni-hamburg.de> Reviewed-by: Ismael Luceno <ismael@iodev.co.uk> Cc: Balbir Singh <bsingharora@gmail.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: xu xin <xu.xin16@zte.com.cn> Cc: Yang Yang <yang.yang29@zte.com.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Chris von Recklinghausen <crecklin@redhat.com>
2023-03-24 11:43:37 +00:00
u64 now_ns, delta;
time64_t btime;
BUILD_BUG_ON(TS_COMM_LEN < TASK_COMM_LEN);
/* calculate task elapsed time in nsec */
taskstats: version 12 with thread group and exe info Bugzilla: https://bugzilla.redhat.com/2160210 commit 0e0af57e0e91b304f36b7d1dba859e3c04094273 Author: Dr. Thomas Orgis <thomas.orgis@uni-hamburg.de> Date: Fri Apr 29 14:38:03 2022 -0700 taskstats: version 12 with thread group and exe info The task exit struct needs some crucial information to be able to provide an enhanced version of process and thread accounting. This change provides: 1. ac_tgid in additon to ac_pid 2. thread group execution walltime in ac_tgetime 3. flag AGROUP in ac_flag to indicate the last task in a thread group / process 4. device ID and inode of task's /proc/self/exe in ac_exe_dev and ac_exe_inode 5. tools/accounting/procacct as demonstrator When a task exits, taskstats are reported to userspace including the task's pid and ppid, but without the id of the thread group this task is part of. Without the tgid, the stats of single tasks cannot be correlated to each other as a thread group (process). The taskstats documentation suggests that on process exit a data set consisting of accumulated stats for the whole group is produced. But such an additional set of stats is only produced for actually multithreaded processes, not groups that had only one thread, and also those stats only contain data about delay accounting and not the more basic information about CPU and memory resource usage. Adding the AGROUP flag to be set when the last task of a group exited enables determination of process end also for single-threaded processes. My applicaton basically does enhanced process accounting with summed cputime, biggest maxrss, tasks per process. The data is not available with the traditional BSD process accounting (which is not designed to be extensible) and the taskstats interface allows more efficient on-the-fly grouping and summing of the stats, anyway, without intermediate disk writes. Furthermore, I do carry statistics on which exact program binary is used how often with associated resources, getting a picture on how important which parts of a collection of installed scientific software in different versions are, and how well they put load on the machine. This is enabled by providing information on /proc/self/exe for each task. I assume the two 64-bit fields for device ID and inode are more appropriate than the possibly large resolved path to keep the data volume down. Add the tgid to the stats to complete task identification, the flag AGROUP to mark the last task of a group, the group wallclock time, and inode-based identification of the associated executable file. Add tools/accounting/procacct.c as a simplified fork of getdelays.c to demonstrate process and thread accounting. [thomas.orgis@uni-hamburg.de: fix version number in comment] Link: https://lkml.kernel.org/r/20220405003601.7a5f6008@plasteblaster Link: https://lkml.kernel.org/r/20220331004106.64e5616b@plasteblaster Signed-off-by: Dr. Thomas Orgis <thomas.orgis@uni-hamburg.de> Reviewed-by: Ismael Luceno <ismael@iodev.co.uk> Cc: Balbir Singh <bsingharora@gmail.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: xu xin <xu.xin16@zte.com.cn> Cc: Yang Yang <yang.yang29@zte.com.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Chris von Recklinghausen <crecklin@redhat.com>
2023-03-24 11:43:37 +00:00
now_ns = ktime_get_ns();
/* store whole group time first */
delta = now_ns - tsk->group_leader->start_time;
/* Convert to micro seconds */
do_div(delta, NSEC_PER_USEC);
taskstats: version 12 with thread group and exe info Bugzilla: https://bugzilla.redhat.com/2160210 commit 0e0af57e0e91b304f36b7d1dba859e3c04094273 Author: Dr. Thomas Orgis <thomas.orgis@uni-hamburg.de> Date: Fri Apr 29 14:38:03 2022 -0700 taskstats: version 12 with thread group and exe info The task exit struct needs some crucial information to be able to provide an enhanced version of process and thread accounting. This change provides: 1. ac_tgid in additon to ac_pid 2. thread group execution walltime in ac_tgetime 3. flag AGROUP in ac_flag to indicate the last task in a thread group / process 4. device ID and inode of task's /proc/self/exe in ac_exe_dev and ac_exe_inode 5. tools/accounting/procacct as demonstrator When a task exits, taskstats are reported to userspace including the task's pid and ppid, but without the id of the thread group this task is part of. Without the tgid, the stats of single tasks cannot be correlated to each other as a thread group (process). The taskstats documentation suggests that on process exit a data set consisting of accumulated stats for the whole group is produced. But such an additional set of stats is only produced for actually multithreaded processes, not groups that had only one thread, and also those stats only contain data about delay accounting and not the more basic information about CPU and memory resource usage. Adding the AGROUP flag to be set when the last task of a group exited enables determination of process end also for single-threaded processes. My applicaton basically does enhanced process accounting with summed cputime, biggest maxrss, tasks per process. The data is not available with the traditional BSD process accounting (which is not designed to be extensible) and the taskstats interface allows more efficient on-the-fly grouping and summing of the stats, anyway, without intermediate disk writes. Furthermore, I do carry statistics on which exact program binary is used how often with associated resources, getting a picture on how important which parts of a collection of installed scientific software in different versions are, and how well they put load on the machine. This is enabled by providing information on /proc/self/exe for each task. I assume the two 64-bit fields for device ID and inode are more appropriate than the possibly large resolved path to keep the data volume down. Add the tgid to the stats to complete task identification, the flag AGROUP to mark the last task of a group, the group wallclock time, and inode-based identification of the associated executable file. Add tools/accounting/procacct.c as a simplified fork of getdelays.c to demonstrate process and thread accounting. [thomas.orgis@uni-hamburg.de: fix version number in comment] Link: https://lkml.kernel.org/r/20220405003601.7a5f6008@plasteblaster Link: https://lkml.kernel.org/r/20220331004106.64e5616b@plasteblaster Signed-off-by: Dr. Thomas Orgis <thomas.orgis@uni-hamburg.de> Reviewed-by: Ismael Luceno <ismael@iodev.co.uk> Cc: Balbir Singh <bsingharora@gmail.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: xu xin <xu.xin16@zte.com.cn> Cc: Yang Yang <yang.yang29@zte.com.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Chris von Recklinghausen <crecklin@redhat.com>
2023-03-24 11:43:37 +00:00
stats->ac_tgetime = delta;
delta = now_ns - tsk->start_time;
do_div(delta, NSEC_PER_USEC);
stats->ac_etime = delta;
/* Convert to seconds for btime (note y2106 limit) */
btime = ktime_get_real_seconds() - div_u64(delta, USEC_PER_SEC);
stats->ac_btime = clamp_t(time64_t, btime, 0, U32_MAX);
stats->ac_btime64 = btime;
taskstats: Cleanup the use of task->exit_code Bugzilla: https://bugzilla.redhat.com/2120352 commit 1b5a42d9c85f0e731f01c8d1129001fd8531a8a0 Author: Eric W. Biederman <ebiederm@xmission.com> Date: Mon Jan 3 11:32:36 2022 -0600 taskstats: Cleanup the use of task->exit_code In the function bacct_add_task the code reading task->exit_code was introduced in commit f3cef7a99469 ("[PATCH] csa: basic accounting over taskstats"), and it is not entirely clear what the taskstats interface is trying to return as only returning the exit_code of the first task in a process doesn't make a lot of sense. As best as I can figure the intent is to return task->exit_code after a task exits. The field is returned with per task fields, so the exit_code of the entire process is not wanted. Only the value of the first task is returned so this is not a useful way to get the per task ptrace stop code. The ordinary case of returning this value is returning after a task exits, which also precludes use for getting a ptrace value. It is common to for the first task of a process to also be the last task of a process so this field may have done something reasonable by accident in testing. Make ac_exitcode a reliable per task value by always returning it for every exited task. Setting ac_exitcode in a sensible mannter makes it possible to continue to provide this value going forward. Cc: Balbir Singh <bsingharora@gmail.com> Fixes: f3cef7a99469 ("[PATCH] csa: basic accounting over taskstats") Link: https://lkml.kernel.org/r/20220103213312.9144-5-ebiederm@xmission.com Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Chris von Recklinghausen <crecklin@redhat.com>
2022-10-12 11:08:41 +00:00
if (tsk->flags & PF_EXITING)
stats->ac_exitcode = tsk->exit_code;
taskstats: Cleanup the use of task->exit_code Bugzilla: https://bugzilla.redhat.com/2120352 commit 1b5a42d9c85f0e731f01c8d1129001fd8531a8a0 Author: Eric W. Biederman <ebiederm@xmission.com> Date: Mon Jan 3 11:32:36 2022 -0600 taskstats: Cleanup the use of task->exit_code In the function bacct_add_task the code reading task->exit_code was introduced in commit f3cef7a99469 ("[PATCH] csa: basic accounting over taskstats"), and it is not entirely clear what the taskstats interface is trying to return as only returning the exit_code of the first task in a process doesn't make a lot of sense. As best as I can figure the intent is to return task->exit_code after a task exits. The field is returned with per task fields, so the exit_code of the entire process is not wanted. Only the value of the first task is returned so this is not a useful way to get the per task ptrace stop code. The ordinary case of returning this value is returning after a task exits, which also precludes use for getting a ptrace value. It is common to for the first task of a process to also be the last task of a process so this field may have done something reasonable by accident in testing. Make ac_exitcode a reliable per task value by always returning it for every exited task. Setting ac_exitcode in a sensible mannter makes it possible to continue to provide this value going forward. Cc: Balbir Singh <bsingharora@gmail.com> Fixes: f3cef7a99469 ("[PATCH] csa: basic accounting over taskstats") Link: https://lkml.kernel.org/r/20220103213312.9144-5-ebiederm@xmission.com Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Chris von Recklinghausen <crecklin@redhat.com>
2022-10-12 11:08:41 +00:00
if (thread_group_leader(tsk) && (tsk->flags & PF_FORKNOEXEC))
stats->ac_flag |= AFORK;
if (tsk->flags & PF_SUPERPRIV)
stats->ac_flag |= ASU;
if (tsk->flags & PF_DUMPCORE)
stats->ac_flag |= ACORE;
if (tsk->flags & PF_SIGNALED)
stats->ac_flag |= AXSIG;
stats->ac_nice = task_nice(tsk);
stats->ac_sched = tsk->policy;
stats->ac_pid = task_pid_nr_ns(tsk, pid_ns);
taskstats: version 12 with thread group and exe info Bugzilla: https://bugzilla.redhat.com/2160210 commit 0e0af57e0e91b304f36b7d1dba859e3c04094273 Author: Dr. Thomas Orgis <thomas.orgis@uni-hamburg.de> Date: Fri Apr 29 14:38:03 2022 -0700 taskstats: version 12 with thread group and exe info The task exit struct needs some crucial information to be able to provide an enhanced version of process and thread accounting. This change provides: 1. ac_tgid in additon to ac_pid 2. thread group execution walltime in ac_tgetime 3. flag AGROUP in ac_flag to indicate the last task in a thread group / process 4. device ID and inode of task's /proc/self/exe in ac_exe_dev and ac_exe_inode 5. tools/accounting/procacct as demonstrator When a task exits, taskstats are reported to userspace including the task's pid and ppid, but without the id of the thread group this task is part of. Without the tgid, the stats of single tasks cannot be correlated to each other as a thread group (process). The taskstats documentation suggests that on process exit a data set consisting of accumulated stats for the whole group is produced. But such an additional set of stats is only produced for actually multithreaded processes, not groups that had only one thread, and also those stats only contain data about delay accounting and not the more basic information about CPU and memory resource usage. Adding the AGROUP flag to be set when the last task of a group exited enables determination of process end also for single-threaded processes. My applicaton basically does enhanced process accounting with summed cputime, biggest maxrss, tasks per process. The data is not available with the traditional BSD process accounting (which is not designed to be extensible) and the taskstats interface allows more efficient on-the-fly grouping and summing of the stats, anyway, without intermediate disk writes. Furthermore, I do carry statistics on which exact program binary is used how often with associated resources, getting a picture on how important which parts of a collection of installed scientific software in different versions are, and how well they put load on the machine. This is enabled by providing information on /proc/self/exe for each task. I assume the two 64-bit fields for device ID and inode are more appropriate than the possibly large resolved path to keep the data volume down. Add the tgid to the stats to complete task identification, the flag AGROUP to mark the last task of a group, the group wallclock time, and inode-based identification of the associated executable file. Add tools/accounting/procacct.c as a simplified fork of getdelays.c to demonstrate process and thread accounting. [thomas.orgis@uni-hamburg.de: fix version number in comment] Link: https://lkml.kernel.org/r/20220405003601.7a5f6008@plasteblaster Link: https://lkml.kernel.org/r/20220331004106.64e5616b@plasteblaster Signed-off-by: Dr. Thomas Orgis <thomas.orgis@uni-hamburg.de> Reviewed-by: Ismael Luceno <ismael@iodev.co.uk> Cc: Balbir Singh <bsingharora@gmail.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: xu xin <xu.xin16@zte.com.cn> Cc: Yang Yang <yang.yang29@zte.com.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Chris von Recklinghausen <crecklin@redhat.com>
2023-03-24 11:43:37 +00:00
stats->ac_tgid = task_tgid_nr_ns(tsk, pid_ns);
rcu_read_lock();
tcred = __task_cred(tsk);
stats->ac_uid = from_kuid_munged(user_ns, tcred->uid);
stats->ac_gid = from_kgid_munged(user_ns, tcred->gid);
stats->ac_ppid = pid_alive(tsk) ?
task_tgid_nr_ns(rcu_dereference(tsk->real_parent), pid_ns) : 0;
rcu_read_unlock();
task_cputime(tsk, &utime, &stime);
stats->ac_utime = div_u64(utime, NSEC_PER_USEC);
stats->ac_stime = div_u64(stime, NSEC_PER_USEC);
task_cputime_scaled(tsk, &utimescaled, &stimescaled);
stats->ac_utimescaled = div_u64(utimescaled, NSEC_PER_USEC);
stats->ac_stimescaled = div_u64(stimescaled, NSEC_PER_USEC);
stats->ac_minflt = tsk->min_flt;
stats->ac_majflt = tsk->maj_flt;
strncpy(stats->ac_comm, tsk->comm, sizeof(stats->ac_comm));
}
#ifdef CONFIG_TASK_XACCT
#define KB 1024
#define MB (1024*KB)
#define KB_MASK (~(KB-1))
/*
* fill in extended accounting fields
*/
void xacct_add_tsk(struct taskstats *stats, struct task_struct *p)
{
struct mm_struct *mm;
/* convert pages-nsec/1024 to Mbyte-usec, see __acct_update_integrals */
stats->coremem = p->acct_rss_mem1 * PAGE_SIZE;
do_div(stats->coremem, 1000 * KB);
stats->virtmem = p->acct_vm_mem1 * PAGE_SIZE;
do_div(stats->virtmem, 1000 * KB);
mm = get_task_mm(p);
if (mm) {
/* adjust to KB unit */
stats->hiwater_rss = get_mm_hiwater_rss(mm) * PAGE_SIZE / KB;
stats->hiwater_vm = get_mm_hiwater_vm(mm) * PAGE_SIZE / KB;
mmput(mm);
}
stats->read_char = p->ioac.rchar & KB_MASK;
stats->write_char = p->ioac.wchar & KB_MASK;
stats->read_syscalls = p->ioac.syscr & KB_MASK;
stats->write_syscalls = p->ioac.syscw & KB_MASK;
#ifdef CONFIG_TASK_IO_ACCOUNTING
stats->read_bytes = p->ioac.read_bytes & KB_MASK;
stats->write_bytes = p->ioac.write_bytes & KB_MASK;
stats->cancelled_write_bytes = p->ioac.cancelled_write_bytes & KB_MASK;
#else
stats->read_bytes = 0;
stats->write_bytes = 0;
stats->cancelled_write_bytes = 0;
#endif
}
#undef KB
#undef MB
static void __acct_update_integrals(struct task_struct *tsk,
u64 utime, u64 stime)
{
u64 time, delta;
if (!likely(tsk->mm))
return;
time = stime + utime;
delta = time - tsk->acct_timexpd;
if (delta < TICK_NSEC)
return;
tsk->acct_timexpd = time;
/*
* Divide by 1024 to avoid overflow, and to avoid division.
* The final unit reported to userspace is Mbyte-usecs,
* the rest of the math is done in xacct_add_tsk.
*/
tsk->acct_rss_mem1 += delta * get_mm_rss(tsk->mm) >> 10;
mm/mmap.c: fix a data race of mm->total_vm Bugzilla: https://bugzilla.redhat.com/2120352 commit 7866076b924ad4f285bd4596630a8ca7b8333319 Author: Peng Liu <liupeng256@huawei.com> Date: Fri Nov 5 13:38:12 2021 -0700 mm/mmap.c: fix a data race of mm->total_vm The variable mm->total_vm could be accessed concurrently during mmaping and system accounting as noticed by KCSAN, BUG: KCSAN: data-race in __acct_update_integrals / mmap_region read-write to 0xffffa40267bd14c8 of 8 bytes by task 15609 on cpu 3: mmap_region+0x6dc/0x1400 do_mmap+0x794/0xca0 vm_mmap_pgoff+0xdf/0x150 ksys_mmap_pgoff+0xe1/0x380 do_syscall_64+0x37/0x50 entry_SYSCALL_64_after_hwframe+0x44/0xa9 read to 0xffffa40267bd14c8 of 8 bytes by interrupt on cpu 2: __acct_update_integrals+0x187/0x1d0 acct_account_cputime+0x3c/0x40 update_process_times+0x5c/0x150 tick_sched_timer+0x184/0x210 __run_hrtimer+0x119/0x3b0 hrtimer_interrupt+0x350/0xaa0 __sysvec_apic_timer_interrupt+0x7b/0x220 asm_call_irq_on_stack+0x12/0x20 sysvec_apic_timer_interrupt+0x4d/0x80 asm_sysvec_apic_timer_interrupt+0x12/0x20 smp_call_function_single+0x192/0x2b0 perf_install_in_context+0x29b/0x4a0 __se_sys_perf_event_open+0x1a98/0x2550 __x64_sys_perf_event_open+0x63/0x70 do_syscall_64+0x37/0x50 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported by Kernel Concurrency Sanitizer on: CPU: 2 PID: 15610 Comm: syz-executor.3 Not tainted 5.10.0+ #2 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014 In vm_stat_account which called by mmap_region, increase total_vm, and __acct_update_integrals may read total_vm at the same time. This will cause a data race which lead to undefined behaviour. To avoid potential bad read/write, volatile property and barrier are both used to avoid undefined behaviour. Link: https://lkml.kernel.org/r/20210913105550.1569419-1-liupeng256@huawei.com Signed-off-by: Peng Liu <liupeng256@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Chris von Recklinghausen <crecklin@redhat.com>
2022-10-12 11:08:20 +00:00
tsk->acct_vm_mem1 += delta * READ_ONCE(tsk->mm->total_vm) >> 10;
}
/**
* acct_update_integrals - update mm integral fields in task_struct
* @tsk: task_struct for accounting
*/
void acct_update_integrals(struct task_struct *tsk)
{
u64 utime, stime;
unsigned long flags;
local_irq_save(flags);
task_cputime(tsk, &utime, &stime);
__acct_update_integrals(tsk, utime, stime);
local_irq_restore(flags);
}
/**
* acct_account_cputime - update mm integral after cputime update
* @tsk: task_struct for accounting
*/
void acct_account_cputime(struct task_struct *tsk)
{
__acct_update_integrals(tsk, tsk->utime, tsk->stime);
}
/**
* acct_clear_integrals - clear the mm integral fields in task_struct
* @tsk: task_struct whose accounting fields are cleared
*/
void acct_clear_integrals(struct task_struct *tsk)
{
tsk->acct_timexpd = 0;
tsk->acct_rss_mem1 = 0;
tsk->acct_vm_mem1 = 0;
}
#endif