BSD accounting + IO stats

PATCH New Guillaume Thouvenin 1 participant 1 message Jul 2, 2004

Subsystems (5)

VFS Block layer MM core Scheduler +1 more subsystems

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Guillaume Thouvenin

author

2004-07-02 11:36 UTC #0 lore raw

PATCH 1/1 BSD accounting + IO stats

Hello,

I made a small patch to add information about bytes and blocks read
and written. Fields was already in the BSD accounting but they were never updated. The patch is based on the CSA accounting patch.

- It adds four counters in the task_struct (chars read, chars
written, blocks read and blocks written). I think it's intresting to separate read and write even if this difference is not made in the BSD accounting.

- Those fields are updated in:
fs/read_write.c for bytes [in sys_read(), sys_readv(),
sys_write() and sys_writev]
drivers/block/ll_rw_blk.c for blocks [in drive_stat_acct()]

- Modifications are:

   drivers/block/ll_rw_blk.c |    2 ++
   fs/read_write.c           |   12 ++++++++++++
   include/linux/sched.h     |    2 ++
   kernel/acct.c             |    4 ++--
   kernel/fork.c             |    1 +
   5 files changed, 19 insertions(+), 2 deletions(-)

I attach the patch to this email, if there is some problem to read it, it's also available on sourceforge at:
http://sourceforge.net/project/showfiles.php?group_id=105806&package_id=122778&release_id=250321

Hope this help,
Best,

Guillaume

drivers/block/ll_rw_blk.c +2 -0

diff -uprN -X dontdiff linux-2.6.7-vanilla/drivers/block/ll_rw_blk.c linux-2.6.7/drivers/block/ll_rw_blk.c
@@ -1895,10 +1895,12 @@ void drive_stat_acct(struct request *rq,
 
 	if (rw == READ) {
 		disk_stat_add(rq->rq_disk, read_sectors, nr_sectors);
+		current->rblk += nr_sectors;
 		if (!new_io)
 			disk_stat_inc(rq->rq_disk, read_merges);
 	} else if (rw == WRITE) {
 		disk_stat_add(rq->rq_disk, write_sectors, nr_sectors);
+		current->wblk += nr_sectors;
 		if (!new_io)
 			disk_stat_inc(rq->rq_disk, write_merges);
 	}

fs/read_write.c +12 -0

diff -uprN -X dontdiff linux-2.6.7-vanilla/fs/read_write.c linux-2.6.7/fs/read_write.c
@@ -281,6 +281,9 @@ asmlinkage ssize_t sys_read(unsigned int
 		fput_light(file, fput_needed);
 	}
 
+	if (ret > 0) 
+		current->rchar++;
+
 	return ret;
 }
 EXPORT_SYMBOL_GPL(sys_read);

@@ -297,6 +300,9 @@ asmlinkage ssize_t sys_write(unsigned in
 		fput_light(file, fput_needed);
 	}
 
+	if (ret > 0) 
+		current->wchar++;
+
 	return ret;
 }

@@ -519,6 +525,9 @@ sys_readv(unsigned long fd, const struct
 		fput_light(file, fput_needed);
 	}
 
+	if (ret > 0) 
+		current->rchar++;
+
 	return ret;
 }

@@ -535,6 +544,9 @@ sys_writev(unsigned long fd, const struc
 		fput_light(file, fput_needed);
 	}
 
+	if (ret > 0) 
+		current->wchar++;
+
 	return ret;
 }

include/linux/sched.h +2 -0

diff -uprN -X dontdiff linux-2.6.7-vanilla/include/linux/sched.h linux-2.6.7/include/linux/sched.h
@@ -459,6 +459,8 @@ struct task_struct {
 	char comm[16];
 /* file system info */
 	int link_count, total_link_count;
+/* I/O info: chars read/written, blocks read/written */
+	unsigned long rchar, wchar, rblk, wblk;
 /* ipc stuff */
 	struct sysv_sem sysvsem;
 /* CPU-specific state of this task */

kernel/acct.c +2 -2

diff -uprN -X dontdiff linux-2.6.7-vanilla/kernel/acct.c linux-2.6.7/kernel/acct.c
@@ -376,8 +376,8 @@ static void do_acct_process(long exitcod
 	}
 	vsize = vsize / 1024;
 	ac.ac_mem = encode_comp_t(vsize);
-	ac.ac_io = encode_comp_t(0 /* current->io_usage */);	/* %% */
-	ac.ac_rw = encode_comp_t(ac.ac_io / 1024);
+	ac.ac_io = encode_comp_t(current->rchar + current->wchar);
+	ac.ac_rw = encode_comp_t(current->rblk + current->wblk);
 	ac.ac_minflt = encode_comp_t(current->min_flt);
 	ac.ac_majflt = encode_comp_t(current->maj_flt);
 	ac.ac_swaps = encode_comp_t(0);

kernel/fork.c +1 -0

diff -uprN -X dontdiff linux-2.6.7-vanilla/kernel/fork.c linux-2.6.7/kernel/fork.c
@@ -960,6 +960,7 @@ struct task_struct *copy_process(unsigne
 
 	p->utime = p->stime = 0;
 	p->cutime = p->cstime = 0;
+	p->rchar = p->wchar = p->rblk = p->wblk = 0;
 	p->lock_depth = -1;		/* -1 = no lock */
 	p->start_time = get_jiffies_64();
 	p->security = NULL;