[XFS] Remove unused arg from kmem_free()

[deliverable/linux.git] / fs / xfs / support / ktrace.c

diff --git a/fs/xfs/support/ktrace.c b/fs/xfs/support/ktrace.c
index 5cf2e86caa7198653b37f086bf02335d2599fad6..a34ef05489b1c323369c7b22cf40400febaa28dd 100644 (file)
--- a/fs/xfs/support/ktrace.c
+++ b/fs/xfs/support/ktrace.c
@@ -21,10 +21,10 @@ static kmem_zone_t *ktrace_hdr_zone;
 static kmem_zone_t *ktrace_ent_zone;
 static int          ktrace_zentries;
 
-void
+void __init
 ktrace_init(int zentries)
 {
-       ktrace_zentries = zentries;
+       ktrace_zentries = roundup_pow_of_two(zentries);
 
        ktrace_hdr_zone = kmem_zone_init(sizeof(ktrace_t),
                                        "ktrace_hdr");
@@ -36,7 +36,7 @@ ktrace_init(int zentries)
        ASSERT(ktrace_ent_zone);
 }
 
-void
+void __exit
 ktrace_uninit(void)
 {
        kmem_zone_destroy(ktrace_hdr_zone);
@@ -47,13 +47,16 @@ ktrace_uninit(void)
  * ktrace_alloc()
  *
  * Allocate a ktrace header and enough buffering for the given
- * number of entries.
+ * number of entries. Round the number of entries up to a
+ * power of 2 so we can do fast masking to get the index from
+ * the atomic index counter.
  */
 ktrace_t *
 ktrace_alloc(int nentries, unsigned int __nocast sleep)
 {
        ktrace_t        *ktp;
        ktrace_entry_t  *ktep;
+       int             entries;
 
        ktp = (ktrace_t*)kmem_zone_alloc(ktrace_hdr_zone, sleep);
 
@@ -70,11 +73,12 @@ ktrace_alloc(int nentries, unsigned int __nocast sleep)
        /*
         * Special treatment for buffers with the ktrace_zentries entries
         */
-       if (nentries == ktrace_zentries) {
+       entries = roundup_pow_of_two(nentries);
+       if (entries == ktrace_zentries) {
                ktep = (ktrace_entry_t*)kmem_zone_zalloc(ktrace_ent_zone,
                                                            sleep);
        } else {
-               ktep = (ktrace_entry_t*)kmem_zalloc((nentries * sizeof(*ktep)),
+               ktep = (ktrace_entry_t*)kmem_zalloc((entries * sizeof(*ktep)),
                                                            sleep | KM_LARGE);
        }
 
@@ -85,16 +89,16 @@ ktrace_alloc(int nentries, unsigned int __nocast sleep)
                if (sleep & KM_SLEEP)
                        panic("ktrace_alloc: NULL memory on KM_SLEEP request!");
 
-               kmem_free(ktp, sizeof(*ktp));
+               kmem_free(ktp);
 
                return NULL;
        }
 
-       spinlock_init(&(ktp->kt_lock), "kt_lock");
-
        ktp->kt_entries  = ktep;
-       ktp->kt_nentries = nentries;
-       ktp->kt_index    = 0;
+       ktp->kt_nentries = entries;
+       ASSERT(is_power_of_2(entries));
+       ktp->kt_index_mask = entries - 1;
+       atomic_set(&ktp->kt_index, 0);
        ktp->kt_rollover = 0;
        return ktp;
 }
@@ -114,8 +118,6 @@ ktrace_free(ktrace_t *ktp)
        if (ktp == (ktrace_t *)NULL)
                return;
 
-       spinlock_destroy(&ktp->kt_lock);
-
        /*
         * Special treatment for the Vnode trace buffer.
         */
@@ -124,7 +126,7 @@ ktrace_free(ktrace_t *ktp)
        } else {
                entries_size = (int)(ktp->kt_nentries * sizeof(ktrace_entry_t));
 
-               kmem_free(ktp->kt_entries, entries_size);
+               kmem_free(ktp->kt_entries);
        }
 
        kmem_zone_free(ktrace_hdr_zone, ktp);
@@ -155,8 +157,6 @@ ktrace_enter(
        void            *val14,
        void            *val15)
 {
-       static DEFINE_SPINLOCK(wrap_lock);
-       unsigned long   flags;
        int             index;
        ktrace_entry_t  *ktep;
 
@@ -165,12 +165,8 @@ ktrace_enter(
        /*
         * Grab an entry by pushing the index up to the next one.
         */
-       spin_lock_irqsave(&wrap_lock, flags);
-       index = ktp->kt_index;
-       if (++ktp->kt_index == ktp->kt_nentries)
-               ktp->kt_index = 0;
-       spin_unlock_irqrestore(&wrap_lock, flags);
-
+       index = atomic_add_return(1, &ktp->kt_index);
+       index = (index - 1) & ktp->kt_index_mask;
        if (!ktp->kt_rollover && index == ktp->kt_nentries - 1)
                ktp->kt_rollover = 1;
 
@@ -203,11 +199,12 @@ int
 ktrace_nentries(
        ktrace_t        *ktp)
 {
-       if (ktp == NULL) {
+       int     index;
+       if (ktp == NULL)
                return 0;
-       }
 
-       return (ktp->kt_rollover ? ktp->kt_nentries : ktp->kt_index);
+       index = atomic_read(&ktp->kt_index) & ktp->kt_index_mask;
+       return (ktp->kt_rollover ? ktp->kt_nentries : index);
 }
 
 /*
@@ -232,7 +229,7 @@ ktrace_first(ktrace_t   *ktp, ktrace_snap_t     *ktsp)
        int             nentries;
 
        if (ktp->kt_rollover)
-               index = ktp->kt_index;
+               index = atomic_read(&ktp->kt_index) & ktp->kt_index_mask;
        else
                index = 0;