From: Ohad Ben-Cohen <o...@wizery.com> rwlocks are slower and have potential starvation issues therefore spinlocks are generally preferred.
see also: http://lwn.net/Articles/364583/ Signed-off-by: Ohad Ben-Cohen <o...@wizery.com> Signed-off-by: Kanigeri Hari <h-kanige...@ti.com> Signed-off-by: Hiroshi DOYU <hiroshi.d...@nokia.com> --- arch/arm/plat-omap/mailbox.c | 30 +++++++++++++++--------------- 1 files changed, 15 insertions(+), 15 deletions(-) diff --git a/arch/arm/plat-omap/mailbox.c b/arch/arm/plat-omap/mailbox.c index 08a2df7..af3a6ac 100644 --- a/arch/arm/plat-omap/mailbox.c +++ b/arch/arm/plat-omap/mailbox.c @@ -31,7 +31,7 @@ static struct workqueue_struct *mboxd; static struct omap_mbox *mboxes; -static DEFINE_RWLOCK(mboxes_lock); +static DEFINE_SPINLOCK(mboxes_lock); static int mbox_configured; @@ -249,16 +249,16 @@ static int omap_mbox_startup(struct omap_mbox *mbox) struct omap_mbox_queue *mq; if (likely(mbox->ops->startup)) { - write_lock(&mboxes_lock); + spin_lock(&mboxes_lock); if (!mbox_configured) ret = mbox->ops->startup(mbox); if (unlikely(ret)) { - write_unlock(&mboxes_lock); + spin_unlock(&mboxes_lock); return ret; } mbox_configured++; - write_unlock(&mboxes_lock); + spin_unlock(&mboxes_lock); } ret = request_irq(mbox->irq, mbox_interrupt, IRQF_SHARED, @@ -304,12 +304,12 @@ static void omap_mbox_fini(struct omap_mbox *mbox) free_irq(mbox->irq, mbox); if (unlikely(mbox->ops->shutdown)) { - write_lock(&mboxes_lock); + spin_lock(&mboxes_lock); if (mbox_configured > 0) mbox_configured--; if (!mbox_configured) mbox->ops->shutdown(mbox); - write_unlock(&mboxes_lock); + spin_unlock(&mboxes_lock); } } @@ -330,14 +330,14 @@ struct omap_mbox *omap_mbox_get(const char *name) struct omap_mbox *mbox; int ret; - read_lock(&mboxes_lock); + spin_lock(&mboxes_lock); mbox = *(find_mboxes(name)); if (mbox == NULL) { - read_unlock(&mboxes_lock); + spin_unlock(&mboxes_lock); return ERR_PTR(-ENOENT); } - read_unlock(&mboxes_lock); + spin_unlock(&mboxes_lock); ret = omap_mbox_startup(mbox); if (ret) @@ -363,15 +363,15 @@ int omap_mbox_register(struct device *parent, struct omap_mbox *mbox) if (mbox->next) return -EBUSY; - write_lock(&mboxes_lock); + spin_lock(&mboxes_lock); tmp = find_mboxes(mbox->name); if (*tmp) { ret = -EBUSY; - write_unlock(&mboxes_lock); + spin_unlock(&mboxes_lock); goto err_find; } *tmp = mbox; - write_unlock(&mboxes_lock); + spin_unlock(&mboxes_lock); return 0; @@ -384,18 +384,18 @@ int omap_mbox_unregister(struct omap_mbox *mbox) { struct omap_mbox **tmp; - write_lock(&mboxes_lock); + spin_lock(&mboxes_lock); tmp = &mboxes; while (*tmp) { if (mbox == *tmp) { *tmp = mbox->next; mbox->next = NULL; - write_unlock(&mboxes_lock); + spin_unlock(&mboxes_lock); return 0; } tmp = &(*tmp)->next; } - write_unlock(&mboxes_lock); + spin_unlock(&mboxes_lock); return -EINVAL; } -- 1.7.1.rc1 -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
