diff options
| author | Li Zhijian <lizhijian@cn.fujitsu.com> | 2021-10-25 11:26:57 +0800 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@kernel.org> | 2021-11-30 17:29:50 -0800 |
| commit | 9880eb878c315b241002d43d7ff89df23713a51b (patch) | |
| tree | 7fff07967678053f4d34ebb63ff1bba9d85ccf37 /kernel/rcu/refscale.c | |
| parent | c30c876312f66b0422a1d632b8c45b6416deeec0 (diff) | |
refscale: Prevent buffer to pr_alert() being too long
0Day/LKP observed that the refscale results fail to complete when larger
values of nrun (such as 300) are specified. The problem is that printk()
can accept at most a 1024-byte buffer. This commit therefore prints
the buffer whenever its length exceeds 800 bytes.
CC: Philip Li <philip.li@intel.com>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Diffstat (limited to 'kernel/rcu/refscale.c')
| -rw-r--r-- | kernel/rcu/refscale.c | 23 |
1 files changed, 13 insertions, 10 deletions
diff --git a/kernel/rcu/refscale.c b/kernel/rcu/refscale.c index b59457cef88d..d8ed1ca3adc0 100644 --- a/kernel/rcu/refscale.c +++ b/kernel/rcu/refscale.c @@ -604,7 +604,7 @@ static u64 process_durations(int n) char *buf; u64 sum = 0; - buf = kmalloc(128 + nreaders * 32, GFP_KERNEL); + buf = kmalloc(800 + 64, GFP_KERNEL); if (!buf) return 0; buf[0] = 0; @@ -617,13 +617,15 @@ static u64 process_durations(int n) if (i % 5 == 0) strcat(buf, "\n"); + if (strlen(buf) >= 800) { + pr_alert("%s", buf); + buf[0] = 0; + } strcat(buf, buf1); sum += rt->last_duration_ns; } - strcat(buf, "\n"); - - SCALEOUT("%s\n", buf); + pr_alert("%s\n", buf); kfree(buf); return sum; @@ -647,7 +649,7 @@ static int main_func(void *arg) VERBOSE_SCALEOUT("main_func task started"); result_avg = kzalloc(nruns * sizeof(*result_avg), GFP_KERNEL); - buf = kzalloc(64 + nruns * 32, GFP_KERNEL); + buf = kzalloc(800 + 64, GFP_KERNEL); if (!result_avg || !buf) { VERBOSE_SCALEOUT_ERRSTRING("out of memory"); goto oom_exit; @@ -695,10 +697,7 @@ static int main_func(void *arg) // Print the average of all experiments SCALEOUT("END OF TEST. Calculating average duration per loop (nanoseconds)...\n"); - buf[0] = 0; - strcat(buf, "\n"); - strcat(buf, "Runs\tTime(ns)\n"); - + pr_alert("Runs\tTime(ns)\n"); for (exp = 0; exp < nruns; exp++) { u64 avg; u32 rem; @@ -706,9 +705,13 @@ static int main_func(void *arg) avg = div_u64_rem(result_avg[exp], 1000, &rem); sprintf(buf1, "%d\t%llu.%03u\n", exp + 1, avg, rem); strcat(buf, buf1); + if (strlen(buf) >= 800) { + pr_alert("%s", buf); + buf[0] = 0; + } } - SCALEOUT("%s", buf); + pr_alert("%s", buf); oom_exit: // This will shutdown everything including us. |