diff options
| author | Brian Behlendorf <[email protected]> | 2009-12-04 15:54:12 -0800 |
|---|---|---|
| committer | Brian Behlendorf <[email protected]> | 2009-12-04 15:54:12 -0800 |
| commit | d04c8a563c09d6449d5663aa2b57840653defae5 (patch) | |
| tree | dabaa7102180f3c4e18ac21e1f7fc3618e996bdb /module/spl/spl-proc.c | |
| parent | db1aa22297d50fa19939e487b5cc7d1f5088c64e (diff) | |
Atomic64 compatibility for 32-bit systems without kernel support.
This patch is another step towards updating the code to handle the
32-bit kernels which I have not been regularly testing. This changes
do not really impact the common case I'm expected which is the latest
kernel running on an x86_64 arch.
Until the linux-2.6.31 kernel the x86 arch did not have support for
64-bit atomic operations. Additionally, the new atomic_compat.h support
for this case was wrong because it embedded a spinlock in the atomic
variable which must always and only be 64-bits total. To handle these
32-bit issues we now simply fall back to the --enable-atomic-spinlock
implementation if the kernel does not provide the 64-bit atomic funcs.
The second issue this patch addresses is the DEBUG_KMEM assumption that
there will always be atomic64 funcs available. On 32-bit archs this may
not be true, and actually that's just fine. In that case the kernel will
will never be able to allocate more the 32-bits worth anyway. So just
check if atomic64 funcs are available, if they are not it means this
is a 32-bit machine and we can safely use atomic_t's instead.
Diffstat (limited to 'module/spl/spl-proc.c')
| -rw-r--r-- | module/spl/spl-proc.c | 20 |
1 files changed, 16 insertions, 4 deletions
diff --git a/module/spl/spl-proc.c b/module/spl/spl-proc.c index 08bcac625..dcd686c9e 100644 --- a/module/spl/spl-proc.c +++ b/module/spl/spl-proc.c @@ -409,8 +409,8 @@ proc_console_backoff(struct ctl_table *table, int write, struct file *filp, #ifdef DEBUG_KMEM static int -proc_doatomic64(struct ctl_table *table, int write, struct file *filp, - void __user *buffer, size_t *lenp, loff_t *ppos) +proc_domemused(struct ctl_table *table, int write, struct file *filp, + void __user *buffer, size_t *lenp, loff_t *ppos) { int rc = 0; unsigned long min = 0, max = ~0, val; @@ -425,7 +425,11 @@ proc_doatomic64(struct ctl_table *table, int write, struct file *filp, if (write) { *ppos += *lenp; } else { +# ifdef HAVE_ATOMIC64_T val = atomic64_read((atomic64_t *)table->data); +# else + val = atomic_read((atomic_t *)table->data); +# endif /* HAVE_ATOMIC64_T */ rc = proc_doulongvec_minmax(&dummy, write, filp, buffer, lenp, ppos); } @@ -861,9 +865,13 @@ static struct ctl_table spl_kmem_table[] = { .ctl_name = CTL_KMEM_KMEMUSED, .procname = "kmem_used", .data = &kmem_alloc_used, +# ifdef HAVE_ATOMIC64_T .maxlen = sizeof(atomic64_t), +# else + .maxlen = sizeof(atomic_t), +# endif /* HAVE_ATOMIC64_T */ .mode = 0444, - .proc_handler = &proc_doatomic64, + .proc_handler = &proc_domemused, }, { .ctl_name = CTL_KMEM_KMEMMAX, @@ -879,9 +887,13 @@ static struct ctl_table spl_kmem_table[] = { .ctl_name = CTL_KMEM_VMEMUSED, .procname = "vmem_used", .data = &vmem_alloc_used, +# ifdef HAVE_ATOMIC64_T .maxlen = sizeof(atomic64_t), +# else + .maxlen = sizeof(atomic_t), +# endif /* HAVE_ATOMIC64_T */ .mode = 0444, - .proc_handler = &proc_doatomic64, + .proc_handler = &proc_domemused, }, { .ctl_name = CTL_KMEM_VMEMMAX, |