Gitweb:     
http://git.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=4b98d11b40f03382918796f3c5c936d5495d20a4
Commit:     4b98d11b40f03382918796f3c5c936d5495d20a4
Parent:     18f705f49a5b19206233f7cef8f869ce7291f8c8
Author:     Alexey Dobriyan <[EMAIL PROTECTED]>
AuthorDate: Sat Feb 10 01:46:45 2007 -0800
Committer:  Linus Torvalds <[EMAIL PROTECTED]>
CommitDate: Sun Feb 11 11:18:07 2007 -0800

    [PATCH] ifdef ->rchar, ->wchar, ->syscr, ->syscw from task_struct
    
    They are fat: 4x8 bytes in task_struct.
    They are uncoditionally updated in every fork, read, write and sendfile.
    They are used only if you have some "extended acct fields feature".
    
    And please, please, please, read(2) knows about bytes, not characters,
    why it is called "rchar"?
    
    Signed-off-by: Alexey Dobriyan <[EMAIL PROTECTED]>
    Cc: Jay Lan <[EMAIL PROTECTED]>
    Cc: Balbir Singh <[EMAIL PROTECTED]>
    Signed-off-by: Andrew Morton <[EMAIL PROTECTED]>
    Signed-off-by: Linus Torvalds <[EMAIL PROTECTED]>
---
 fs/proc/base.c        |    4 ++++
 fs/read_write.c       |   24 ++++++++++++------------
 include/linux/sched.h |   40 ++++++++++++++++++++++++++++++++++++++++
 kernel/fork.c         |    2 ++
 4 files changed, 58 insertions(+), 12 deletions(-)

diff --git a/fs/proc/base.c b/fs/proc/base.c
index 1a979ea..7fb37d6 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -1810,17 +1810,21 @@ static int proc_base_fill_cache(struct file *filp, void 
*dirent, filldir_t filld
 static int proc_pid_io_accounting(struct task_struct *task, char *buffer)
 {
        return sprintf(buffer,
+#ifdef CONFIG_TASK_XACCT
                        "rchar: %llu\n"
                        "wchar: %llu\n"
                        "syscr: %llu\n"
                        "syscw: %llu\n"
+#endif
                        "read_bytes: %llu\n"
                        "write_bytes: %llu\n"
                        "cancelled_write_bytes: %llu\n",
+#ifdef CONFIG_TASK_XACCT
                        (unsigned long long)task->rchar,
                        (unsigned long long)task->wchar,
                        (unsigned long long)task->syscr,
                        (unsigned long long)task->syscw,
+#endif
                        (unsigned long long)task->ioac.read_bytes,
                        (unsigned long long)task->ioac.write_bytes,
                        (unsigned long long)task->ioac.cancelled_write_bytes);
diff --git a/fs/read_write.c b/fs/read_write.c
index 707ac21..bcb0ef2 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -274,9 +274,9 @@ ssize_t vfs_read(struct file *file, char __user *buf, 
size_t count, loff_t *pos)
                                ret = do_sync_read(file, buf, count, pos);
                        if (ret > 0) {
                                fsnotify_access(file->f_path.dentry);
-                               current->rchar += ret;
+                               add_rchar(current, ret);
                        }
-                       current->syscr++;
+                       inc_syscr(current);
                }
        }
 
@@ -332,9 +332,9 @@ ssize_t vfs_write(struct file *file, const char __user 
*buf, size_t count, loff_
                                ret = do_sync_write(file, buf, count, pos);
                        if (ret > 0) {
                                fsnotify_modify(file->f_path.dentry);
-                               current->wchar += ret;
+                               add_wchar(current, ret);
                        }
-                       current->syscw++;
+                       inc_syscw(current);
                }
        }
 
@@ -675,8 +675,8 @@ sys_readv(unsigned long fd, const struct iovec __user *vec, 
unsigned long vlen)
        }
 
        if (ret > 0)
-               current->rchar += ret;
-       current->syscr++;
+               add_rchar(current, ret);
+       inc_syscr(current);
        return ret;
 }
 
@@ -696,8 +696,8 @@ sys_writev(unsigned long fd, const struct iovec __user 
*vec, unsigned long vlen)
        }
 
        if (ret > 0)
-               current->wchar += ret;
-       current->syscw++;
+               add_wchar(current, ret);
+       inc_syscw(current);
        return ret;
 }
 
@@ -779,12 +779,12 @@ static ssize_t do_sendfile(int out_fd, int in_fd, loff_t 
*ppos,
        retval = in_file->f_op->sendfile(in_file, ppos, count, file_send_actor, 
out_file);
 
        if (retval > 0) {
-               current->rchar += retval;
-               current->wchar += retval;
+               add_rchar(current, retval);
+               add_wchar(current, retval);
        }
-       current->syscr++;
-       current->syscw++;
 
+       inc_syscr(current);
+       inc_syscw(current);
        if (*ppos > max)
                retval = -EOVERFLOW;
 
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 4463735..76c8e2d 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1013,8 +1013,10 @@ struct task_struct {
  * to a stack based synchronous wait) if its doing sync IO.
  */
        wait_queue_t *io_wait;
+#ifdef CONFIG_TASK_XACCT
 /* i/o counters(bytes read/written, #syscalls */
        u64 rchar, wchar, syscr, syscw;
+#endif
        struct task_io_accounting ioac;
 #if defined(CONFIG_TASK_XACCT)
        u64 acct_rss_mem1;      /* accumulated rss usage */
@@ -1649,6 +1651,44 @@ extern int 
sched_create_sysfs_power_savings_entries(struct sysdev_class *cls);
 
 extern void normalize_rt_tasks(void);
 
+#ifdef CONFIG_TASK_XACCT
+static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
+{
+       tsk->rchar += amt;
+}
+
+static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
+{
+       tsk->wchar += amt;
+}
+
+static inline void inc_syscr(struct task_struct *tsk)
+{
+       tsk->syscr++;
+}
+
+static inline void inc_syscw(struct task_struct *tsk)
+{
+       tsk->syscw++;
+}
+#else
+static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
+{
+}
+
+static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
+{
+}
+
+static inline void inc_syscr(struct task_struct *tsk)
+{
+}
+
+static inline void inc_syscw(struct task_struct *tsk)
+{
+}
+#endif
+
 #endif /* __KERNEL__ */
 
 #endif
diff --git a/kernel/fork.c b/kernel/fork.c
index d57118d..80284eb 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1038,10 +1038,12 @@ static struct task_struct *copy_process(unsigned long 
clone_flags,
        p->utime = cputime_zero;
        p->stime = cputime_zero;
        p->sched_time = 0;
+#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);
        acct_clear_integrals(p);
 
-
To unsubscribe from this list: send the line "unsubscribe git-commits-head" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to