lkml.org 
[lkml]   [2020]   [Mar]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Date
Subject[RFC PATCH v1 13/50] Avoid some useless msecs/jiffies conversions
Rather than generating a random number of milliseconds in a
constant range and then converting to jiffies, convert the range
to jiffies (evaluated at compile time) and choose a random number
of jiffies in that range.

Likewise, "msecs_to_jiffies(seconds * 1000)" is more
conveniently written "seconds * HZ".

Signed-off-by: George Spelvin <lkml@sdf.org>
Cc: Hannes Reinecke <hare@suse.de>
Cc: linux-scsi@vger.kernel.org
Cc: Marek Lindner <mareklindner@neomailbox.ch>
Cc: Simon Wunderlich <sw@simonwunderlich.de>
Cc: Antonio Quartulli <a@unstable.cc>
Cc: Sven Eckelmann <sven@narfation.org>
Cc: b.a.t.m.a.n@lists.open-mesh.org
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: linux-wireless@vger.kernel.org
Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Takashi Iwai <tiwai@suse.com>
Cc: alsa-devel@alsa-project.org
---
drivers/scsi/fcoe/fcoe_ctlr.c | 10 +++++-----
net/batman-adv/bat_iv_ogm.c | 2 +-
net/batman-adv/bat_v_ogm.c | 8 ++++----
net/bluetooth/hci_request.c | 2 +-
net/wireless/scan.c | 2 +-
sound/core/pcm_lib.c | 2 +-
sound/core/pcm_native.c | 2 +-
7 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/drivers/scsi/fcoe/fcoe_ctlr.c b/drivers/scsi/fcoe/fcoe_ctlr.c
index 1791a393795da..9c530f8827518 100644
--- a/drivers/scsi/fcoe/fcoe_ctlr.c
+++ b/drivers/scsi/fcoe/fcoe_ctlr.c
@@ -2238,10 +2238,10 @@ static void fcoe_ctlr_vn_restart(struct fcoe_ctlr *fip)

if (fip->probe_tries < FIP_VN_RLIM_COUNT) {
fip->probe_tries++;
- wait = prandom_u32() % FIP_VN_PROBE_WAIT;
+ wait = prandom_u32_max(msecs_to_jiffies(FIP_VN_PROBE_WAIT));
} else
- wait = FIP_VN_RLIM_INT;
- mod_timer(&fip->timer, jiffies + msecs_to_jiffies(wait));
+ wait = msecs_to_jiffies(FIP_VN_RLIM_INT);
+ mod_timer(&fip->timer, jiffies + wait);
fcoe_ctlr_set_state(fip, FIP_ST_VNMP_START);
}

@@ -3132,8 +3132,8 @@ static void fcoe_ctlr_vn_timeout(struct fcoe_ctlr *fip)
fcoe_ctlr_vn_send(fip, FIP_SC_VN_BEACON,
fcoe_all_vn2vn, 0);
fip->port_ka_time = jiffies +
- msecs_to_jiffies(FIP_VN_BEACON_INT +
- (prandom_u32() % FIP_VN_BEACON_FUZZ));
+ msecs_to_jiffies(FIP_VN_BEACON_INT) +
+ prandom_u32_max(msecs_to_jiffies(FIP_VN_BEACON_FUZZ));
}
if (time_before(fip->port_ka_time, next_time))
next_time = fip->port_ka_time;
diff --git a/net/batman-adv/bat_iv_ogm.c b/net/batman-adv/bat_iv_ogm.c
index 46c5cd9f8019e..9efd96e91d53e 100644
--- a/net/batman-adv/bat_iv_ogm.c
+++ b/net/batman-adv/bat_iv_ogm.c
@@ -288,7 +288,7 @@ batadv_iv_ogm_emit_send_time(const struct batadv_priv *bat_priv)
/* when do we schedule a ogm packet to be sent */
static unsigned long batadv_iv_ogm_fwd_send_time(void)
{
- return jiffies + msecs_to_jiffies(prandom_u32() % (BATADV_JITTER / 2));
+ return jiffies + prandom_u32_max(msecs_to_jiffies(BATADV_JITTER / 2));
}

/* apply hop penalty for a normal link */
diff --git a/net/batman-adv/bat_v_ogm.c b/net/batman-adv/bat_v_ogm.c
index 411ce5fc6492f..61fa742ff5501 100644
--- a/net/batman-adv/bat_v_ogm.c
+++ b/net/batman-adv/bat_v_ogm.c
@@ -85,12 +85,12 @@ struct batadv_orig_node *batadv_v_ogm_orig_get(struct batadv_priv *bat_priv,
*/
static void batadv_v_ogm_start_queue_timer(struct batadv_hard_iface *hard_iface)
{
- unsigned int msecs = BATADV_MAX_AGGREGATION_MS * 1000;
+ unsigned int delay = msecs_to_jiffies(BATADV_MAX_AGGREGATION_MS);

- /* msecs * [0.9, 1.1] */
- msecs += prandom_u32() % (msecs / 5) - (msecs / 10);
+ /* delay * [0.9, 1.1] */
+ delay += prandom_u32_max(delay / 5) - (delay / 10);
queue_delayed_work(batadv_event_workqueue, &hard_iface->bat_v.aggr_wq,
- msecs_to_jiffies(msecs / 1000));
+ delay);
}

/**
diff --git a/net/bluetooth/hci_request.c b/net/bluetooth/hci_request.c
index 2a1b64dbf76e4..8b46e23b4abe7 100644
--- a/net/bluetooth/hci_request.c
+++ b/net/bluetooth/hci_request.c
@@ -1505,7 +1505,7 @@ int hci_get_random_address(struct hci_dev *hdev, bool require_privacy,

bacpy(rand_addr, &hdev->rpa);

- to = msecs_to_jiffies(hdev->rpa_timeout * 1000);
+ to = hdev->rpa_timeout * HZ;
if (adv_instance)
queue_delayed_work(hdev->workqueue,
&adv_instance->rpa_expired_cb, to);
diff --git a/net/wireless/scan.c b/net/wireless/scan.c
index aef240fdf8df6..b6856cbb68d3b 100644
--- a/net/wireless/scan.c
+++ b/net/wireless/scan.c
@@ -700,7 +700,7 @@ void cfg80211_bss_age(struct cfg80211_registered_device *rdev,
unsigned long age_secs)
{
struct cfg80211_internal_bss *bss;
- unsigned long age_jiffies = msecs_to_jiffies(age_secs * MSEC_PER_SEC);
+ unsigned long age_jiffies = age_secs * HZ;

spin_lock_bh(&rdev->bss_lock);
list_for_each_entry(bss, &rdev->bss_list, list)
diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c
index 2236b5e0c1f25..8a2bf333200c1 100644
--- a/sound/core/pcm_lib.c
+++ b/sound/core/pcm_lib.c
@@ -1839,7 +1839,7 @@ static int wait_for_avail(struct snd_pcm_substream *substream,
runtime->rate;
wait_time = max(t, wait_time);
}
- wait_time = msecs_to_jiffies(wait_time * 1000);
+ wait_time *= HZ;
}
}

diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c
index df40d38f6e290..1ea763f9f956d 100644
--- a/sound/core/pcm_native.c
+++ b/sound/core/pcm_native.c
@@ -1937,7 +1937,7 @@ static int snd_pcm_drain(struct snd_pcm_substream *substream,
long t = runtime->period_size * 2 / runtime->rate;
tout = max(t, tout);
}
- tout = msecs_to_jiffies(tout * 1000);
+ tout *= HZ;
}
tout = schedule_timeout(tout);

--
2.26.0
\
 
 \ /
  Last update: 2020-03-28 17:47    [W:0.084 / U:0.608 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site