Commit 5995477a authored by Andrea Righi's avatar Andrea Righi Committed by Linus Torvalds

task IO accounting: improve code readability

Put all i/o statistics in struct proc_io_accounting and use inline functions to
initialize and increment statistics, removing a lot of single variable
assignments.

This also reduces the kernel size as following (with CONFIG_TASK_XACCT=y and
CONFIG_TASK_IO_ACCOUNTING=y).

    text    data     bss     dec     hex filename
   11651       0       0   11651    2d83 kernel/exit.o.before
   11619       0       0   11619    2d63 kernel/exit.o.after
   10886     132     136   11154    2b92 kernel/fork.o.before
   10758     132     136   11026    2b12 kernel/fork.o.after

 3082029  807968 4818600 8708597  84e1f5 vmlinux.o.before
 3081869  807968 4818600 8708437  84e155 vmlinux.o.after
Signed-off-by: default avatarAndrea Righi <righi.andrea@gmail.com>
Acked-by: default avatarOleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 605ccb73
......@@ -53,6 +53,7 @@
#include <linux/time.h>
#include <linux/proc_fs.h>
#include <linux/stat.h>
#include <linux/task_io_accounting_ops.h>
#include <linux/init.h>
#include <linux/capability.h>
#include <linux/file.h>
......@@ -2402,44 +2403,17 @@ static int proc_base_fill_cache(struct file *filp, void *dirent,
#ifdef CONFIG_TASK_IO_ACCOUNTING
static int do_io_accounting(struct task_struct *task, char *buffer, int whole)
{
u64 rchar, wchar, syscr, syscw;
struct task_io_accounting ioac;
rchar = task->rchar;
wchar = task->wchar;
syscr = task->syscr;
syscw = task->syscw;
memcpy(&ioac, &task->ioac, sizeof(ioac));
if (whole) {
unsigned long flags;
if (lock_task_sighand(task, &flags)) {
struct signal_struct *sig = task->signal;
struct task_struct *t = task;
rchar += sig->rchar;
wchar += sig->wchar;
syscr += sig->syscr;
syscw += sig->syscw;
ioac.read_bytes += sig->ioac.read_bytes;
ioac.write_bytes += sig->ioac.write_bytes;
ioac.cancelled_write_bytes +=
sig->ioac.cancelled_write_bytes;
while_each_thread(task, t) {
rchar += t->rchar;
wchar += t->wchar;
syscr += t->syscr;
syscw += t->syscw;
ioac.read_bytes += t->ioac.read_bytes;
ioac.write_bytes += t->ioac.write_bytes;
ioac.cancelled_write_bytes +=
t->ioac.cancelled_write_bytes;
}
unlock_task_sighand(task, &flags);
}
struct proc_io_accounting acct = task->ioac;
unsigned long flags;
if (whole && lock_task_sighand(task, &flags)) {
struct task_struct *t = task;
task_io_accounting_add(&acct, &task->signal->ioac);
while_each_thread(task, t)
task_io_accounting_add(&acct, &t->ioac);
unlock_task_sighand(task, &flags);
}
return sprintf(buffer,
"rchar: %llu\n"
......@@ -2449,9 +2423,10 @@ static int do_io_accounting(struct task_struct *task, char *buffer, int whole)
"read_bytes: %llu\n"
"write_bytes: %llu\n"
"cancelled_write_bytes: %llu\n",
rchar, wchar, syscr, syscw,
ioac.read_bytes, ioac.write_bytes,
ioac.cancelled_write_bytes);
acct.chr.rchar, acct.chr.wchar,
acct.chr.syscr, acct.chr.syscw,
acct.blk.read_bytes, acct.blk.write_bytes,
acct.blk.cancelled_write_bytes);
}
static int proc_tid_io_accounting(struct task_struct *task, char *buffer)
......
......@@ -505,10 +505,7 @@ struct signal_struct {
unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
unsigned long inblock, oublock, cinblock, coublock;
#ifdef CONFIG_TASK_XACCT
u64 rchar, wchar, syscr, syscw;
#endif
struct task_io_accounting ioac;
struct proc_io_accounting ioac;
/*
* Cumulative ns of scheduled CPU time for dead threads in the
......@@ -1256,11 +1253,7 @@ struct task_struct {
unsigned long ptrace_message;
siginfo_t *last_siginfo; /* For ptrace use. */
#ifdef CONFIG_TASK_XACCT
/* i/o counters(bytes read/written, #syscalls */
u64 rchar, wchar, syscr, syscw;
#endif
struct task_io_accounting ioac;
struct proc_io_accounting ioac;
#if defined(CONFIG_TASK_XACCT)
u64 acct_rss_mem1; /* accumulated rss usage */
u64 acct_vm_mem1; /* accumulated virtual memory usage */
......@@ -2190,22 +2183,22 @@ extern long sched_group_rt_period(struct task_group *tg);
#ifdef CONFIG_TASK_XACCT
static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
{
tsk->rchar += amt;
tsk->ioac.chr.rchar += amt;
}
static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
{
tsk->wchar += amt;
tsk->ioac.chr.wchar += amt;
}
static inline void inc_syscr(struct task_struct *tsk)
{
tsk->syscr++;
tsk->ioac.chr.syscr++;
}
static inline void inc_syscw(struct task_struct *tsk)
{
tsk->syscw++;
tsk->ioac.chr.syscw++;
}
#else
static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
......
/*
* task_io_accounting: a structure which is used for recording a single task's
* proc_io_accounting: a structure which is used for recording a single task's
* IO statistics.
*
* Don't include this header file directly - it is designed to be dragged in via
......@@ -8,6 +8,22 @@
* Blame akpm@osdl.org for all this.
*/
#ifdef CONFIG_TASK_XACCT
struct task_chr_io_accounting {
/* bytes read */
u64 rchar;
/* bytes written */
u64 wchar;
/* # of read syscalls */
u64 syscr;
/* # of write syscalls */
u64 syscw;
};
#else /* CONFIG_TASK_XACCT */
struct task_chr_io_accounting {
};
#endif /* CONFIG_TASK_XACCT */
#ifdef CONFIG_TASK_IO_ACCOUNTING
struct task_io_accounting {
/*
......@@ -31,7 +47,12 @@ struct task_io_accounting {
*/
u64 cancelled_write_bytes;
};
#else
#else /* CONFIG_TASK_IO_ACCOUNTING */
struct task_io_accounting {
};
#endif
#endif /* CONFIG_TASK_IO_ACCOUNTING */
struct proc_io_accounting {
struct task_chr_io_accounting chr;
struct task_io_accounting blk;
};
......@@ -9,7 +9,7 @@
#ifdef CONFIG_TASK_IO_ACCOUNTING
static inline void task_io_account_read(size_t bytes)
{
current->ioac.read_bytes += bytes;
current->ioac.blk.read_bytes += bytes;
}
/*
......@@ -18,12 +18,12 @@ static inline void task_io_account_read(size_t bytes)
*/
static inline unsigned long task_io_get_inblock(const struct task_struct *p)
{
return p->ioac.read_bytes >> 9;
return p->ioac.blk.read_bytes >> 9;
}
static inline void task_io_account_write(size_t bytes)
{
current->ioac.write_bytes += bytes;
current->ioac.blk.write_bytes += bytes;
}
/*
......@@ -32,17 +32,25 @@ static inline void task_io_account_write(size_t bytes)
*/
static inline unsigned long task_io_get_oublock(const struct task_struct *p)
{
return p->ioac.write_bytes >> 9;
return p->ioac.blk.write_bytes >> 9;
}
static inline void task_io_account_cancelled_write(size_t bytes)
{
current->ioac.cancelled_write_bytes += bytes;
current->ioac.blk.cancelled_write_bytes += bytes;
}
static inline void task_io_accounting_init(struct task_struct *tsk)
static inline void task_io_accounting_init(struct proc_io_accounting *ioac)
{
memset(&tsk->ioac, 0, sizeof(tsk->ioac));
memset(ioac, 0, sizeof(*ioac));
}
static inline void task_blk_io_accounting_add(struct proc_io_accounting *dst,
struct proc_io_accounting *src)
{
dst->blk.read_bytes += src->blk.read_bytes;
dst->blk.write_bytes += src->blk.write_bytes;
dst->blk.cancelled_write_bytes += src->blk.cancelled_write_bytes;
}
#else
......@@ -69,9 +77,37 @@ static inline void task_io_account_cancelled_write(size_t bytes)
{
}
static inline void task_io_accounting_init(struct task_struct *tsk)
static inline void task_io_accounting_init(struct proc_io_accounting *ioac)
{
}
static inline void task_blk_io_accounting_add(struct proc_io_accounting *dst,
struct proc_io_accounting *src)
{
}
#endif /* CONFIG_TASK_IO_ACCOUNTING */
#endif /* __TASK_IO_ACCOUNTING_OPS_INCLUDED */
#endif /* CONFIG_TASK_IO_ACCOUNTING */
#ifdef CONFIG_TASK_XACCT
static inline void task_chr_io_accounting_add(struct proc_io_accounting *dst,
struct proc_io_accounting *src)
{
dst->chr.rchar += src->chr.rchar;
dst->chr.wchar += src->chr.wchar;
dst->chr.syscr += src->chr.syscr;
dst->chr.syscw += src->chr.syscw;
}
#else
static inline void task_chr_io_accounting_add(struct proc_io_accounting *dst,
struct proc_io_accounting *src)
{
}
#endif /* CONFIG_TASK_XACCT */
static inline void task_io_accounting_add(struct proc_io_accounting *dst,
struct proc_io_accounting *src)
{
task_chr_io_accounting_add(dst, src);
task_blk_io_accounting_add(dst, src);
}
#endif /* __TASK_IO_ACCOUNTING_OPS_INCLUDED */
......@@ -121,18 +121,7 @@ static void __exit_signal(struct task_struct *tsk)
sig->nivcsw += tsk->nivcsw;
sig->inblock += task_io_get_inblock(tsk);
sig->oublock += task_io_get_oublock(tsk);
#ifdef CONFIG_TASK_XACCT
sig->rchar += tsk->rchar;
sig->wchar += tsk->wchar;
sig->syscr += tsk->syscr;
sig->syscw += tsk->syscw;
#endif /* CONFIG_TASK_XACCT */
#ifdef CONFIG_TASK_IO_ACCOUNTING
sig->ioac.read_bytes += tsk->ioac.read_bytes;
sig->ioac.write_bytes += tsk->ioac.write_bytes;
sig->ioac.cancelled_write_bytes +=
tsk->ioac.cancelled_write_bytes;
#endif /* CONFIG_TASK_IO_ACCOUNTING */
task_io_accounting_add(&sig->ioac, &tsk->ioac);
sig->sum_sched_runtime += tsk->se.sum_exec_runtime;
sig = NULL; /* Marker for below. */
}
......@@ -1363,21 +1352,8 @@ static int wait_task_zombie(struct task_struct *p, int options,
psig->coublock +=
task_io_get_oublock(p) +
sig->oublock + sig->coublock;
#ifdef CONFIG_TASK_XACCT
psig->rchar += p->rchar + sig->rchar;
psig->wchar += p->wchar + sig->wchar;
psig->syscr += p->syscr + sig->syscr;
psig->syscw += p->syscw + sig->syscw;
#endif /* CONFIG_TASK_XACCT */
#ifdef CONFIG_TASK_IO_ACCOUNTING
psig->ioac.read_bytes +=
p->ioac.read_bytes + sig->ioac.read_bytes;
psig->ioac.write_bytes +=
p->ioac.write_bytes + sig->ioac.write_bytes;
psig->ioac.cancelled_write_bytes +=
p->ioac.cancelled_write_bytes +
sig->ioac.cancelled_write_bytes;
#endif /* CONFIG_TASK_IO_ACCOUNTING */
task_io_accounting_add(&psig->ioac, &p->ioac);
task_io_accounting_add(&psig->ioac, &sig->ioac);
spin_unlock_irq(&p->parent->sighand->siglock);
}
......
......@@ -806,12 +806,7 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
sig->nvcsw = sig->nivcsw = sig->cnvcsw = sig->cnivcsw = 0;
sig->min_flt = sig->maj_flt = sig->cmin_flt = sig->cmaj_flt = 0;
sig->inblock = sig->oublock = sig->cinblock = sig->coublock = 0;
#ifdef CONFIG_TASK_XACCT
sig->rchar = sig->wchar = sig->syscr = sig->syscw = 0;
#endif
#ifdef CONFIG_TASK_IO_ACCOUNTING
memset(&sig->ioac, 0, sizeof(sig->ioac));
#endif
task_io_accounting_init(&sig->ioac);
sig->sum_sched_runtime = 0;
INIT_LIST_HEAD(&sig->cpu_timers[0]);
INIT_LIST_HEAD(&sig->cpu_timers[1]);
......@@ -994,13 +989,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
p->last_switch_timestamp = 0;
#endif
#ifdef CONFIG_TASK_XACCT
p->rchar = 0; /* I/O counter: bytes read */
p->wchar = 0; /* I/O counter: bytes written */
p->syscr = 0; /* I/O counter: read syscalls */
p->syscw = 0; /* I/O counter: write syscalls */
#endif
task_io_accounting_init(p);
task_io_accounting_init(&p->ioac);
acct_clear_integrals(p);
p->it_virt_expires = cputime_zero;
......
......@@ -94,14 +94,14 @@ void xacct_add_tsk(struct taskstats *stats, struct task_struct *p)
stats->hiwater_vm = mm->hiwater_vm * PAGE_SIZE / KB;
mmput(mm);
}
stats->read_char = p->rchar;
stats->write_char = p->wchar;
stats->read_syscalls = p->syscr;
stats->write_syscalls = p->syscw;
stats->read_char = p->ioac.chr.rchar;
stats->write_char = p->ioac.chr.wchar;
stats->read_syscalls = p->ioac.chr.syscr;
stats->write_syscalls = p->ioac.chr.syscw;
#ifdef CONFIG_TASK_IO_ACCOUNTING
stats->read_bytes = p->ioac.read_bytes;
stats->write_bytes = p->ioac.write_bytes;
stats->cancelled_write_bytes = p->ioac.cancelled_write_bytes;
stats->read_bytes = p->ioac.blk.read_bytes;
stats->write_bytes = p->ioac.blk.write_bytes;
stats->cancelled_write_bytes = p->ioac.blk.cancelled_write_bytes;
#else
stats->read_bytes = 0;
stats->write_bytes = 0;
......
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