Re: [PATCH 1/2] virtio-rng cleanup: move some code out of mutex protection
From: Amit Shah <hidden>
Date: 2014-09-11 06:07:15
Also in:
kvm
On (Wed) 10 Sep 2014 [17:07:06], Amos Kong wrote:
It doesn't save too much cpu time as expected, just a cleanup.
Frankly I won't bother with this. It doesn't completely remove all copying from the mutex, so it's not worthwhile.
quoted hunk ↗ jump to hunk
Signed-off-by: Amos Kong <redacted> --- drivers/char/hw_random/core.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)diff --git a/drivers/char/hw_random/core.c b/drivers/char/hw_random/core.c index aa30a25..c591d7e 100644 --- a/drivers/char/hw_random/core.c +++ b/drivers/char/hw_random/core.c@@ -270,8 +270,8 @@ static ssize_t hwrng_attr_current_show(struct device *dev, return -ERESTARTSYS; if (current_rng) name = current_rng->name; - ret = snprintf(buf, PAGE_SIZE, "%s\n", name); mutex_unlock(&rng_mutex); + ret = snprintf(buf, PAGE_SIZE, "%s\n", name); return ret; }@@ -284,19 +284,19 @@ static ssize_t hwrng_attr_available_show(struct device *dev, ssize_t ret = 0; struct hwrng *rng; + buf[0] = '\0'; err = mutex_lock_interruptible(&rng_mutex); if (err) return -ERESTARTSYS; - buf[0] = '\0'; list_for_each_entry(rng, &rng_list, list) { strncat(buf, rng->name, PAGE_SIZE - ret - 1); ret += strlen(rng->name); strncat(buf, " ", PAGE_SIZE - ret - 1); ret++; } + mutex_unlock(&rng_mutex); strncat(buf, "\n", PAGE_SIZE - ret - 1); ret++; - mutex_unlock(&rng_mutex); return ret; }-- 1.9.3
Amit