diff options
| author | Andrei Vagin <avagin@openvz.org> | 2018-04-10 16:31:26 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-04-11 10:28:33 -0700 |
| commit | d0f02231222b313d1b49278cd2e3c7e7406fea6d (patch) | |
| tree | 697b842799a294ccd856891458cb4820ebd22fee /fs/proc | |
| parent | 48dffbf82d2f17bc6dd3c2b7fd733738ea567914 (diff) | |
proc: replace seq_printf by seq_put_smth to speed up /proc/pid/status
seq_printf() works slower than seq_puts, seq_puts, etc.
== test_proc.c
int main(int argc, char **argv)
{
int n, i, fd;
char buf[16384];
n = atoi(argv[1]);
for (i = 0; i < n; i++) {
fd = open(argv[2], O_RDONLY);
if (fd < 0)
return 1;
if (read(fd, buf, sizeof(buf)) <= 0)
return 1;
close(fd);
}
return 0;
}
==
$ time ./test_proc 1000000 /proc/1/status
== Before path ==
real 0m5.171s
user 0m0.328s
sys 0m4.783s
== After patch ==
real 0m4.761s
user 0m0.334s
sys 0m4.366s
Link: http://lkml.kernel.org/r/20180212074931.7227-4-avagin@openvz.org
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs/proc')
| -rw-r--r-- | fs/proc/array.c | 16 |
1 files changed, 11 insertions, 5 deletions
diff --git a/fs/proc/array.c b/fs/proc/array.c index 851ec0915e4c..ae2c807fd719 100644 --- a/fs/proc/array.c +++ b/fs/proc/array.c @@ -174,7 +174,8 @@ static inline void task_state(struct seq_file *m, struct pid_namespace *ns, if (umask >= 0) seq_printf(m, "Umask:\t%#04o\n", umask); - seq_printf(m, "State:\t%s", get_task_state(p)); + seq_puts(m, "State:\t"); + seq_puts(m, get_task_state(p)); seq_put_decimal_ull(m, "\nTgid:\t", tgid); seq_put_decimal_ull(m, "\nNgid:\t", ngid); @@ -300,8 +301,8 @@ static void render_cap_t(struct seq_file *m, const char *header, seq_puts(m, header); CAP_FOR_EACH_U32(__capi) { - seq_printf(m, "%08x", - a->cap[CAP_LAST_U32 - __capi]); + seq_put_hex_ll(m, NULL, + a->cap[CAP_LAST_U32 - __capi], 8); } seq_putc(m, '\n'); } @@ -355,7 +356,8 @@ static void task_cpus_allowed(struct seq_file *m, struct task_struct *task) static inline void task_core_dumping(struct seq_file *m, struct mm_struct *mm) { - seq_printf(m, "CoreDumping:\t%d\n", !!mm->core_state); + seq_put_decimal_ull(m, "CoreDumping:\t", !!mm->core_state); + seq_putc(m, '\n'); } int proc_pid_status(struct seq_file *m, struct pid_namespace *ns, @@ -491,7 +493,11 @@ static int do_task_stat(struct seq_file *m, struct pid_namespace *ns, /* convert nsec -> ticks */ start_time = nsec_to_clock_t(task->real_start_time); - seq_printf(m, "%d (%s) %c", pid_nr_ns(pid, ns), tcomm, state); + seq_put_decimal_ull(m, "", pid_nr_ns(pid, ns)); + seq_puts(m, " ("); + seq_puts(m, tcomm); + seq_puts(m, ") "); + seq_putc(m, state); seq_put_decimal_ll(m, " ", ppid); seq_put_decimal_ll(m, " ", pgid); seq_put_decimal_ll(m, " ", sid); |