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authorAkinobu Mita <akinobu.mita@gmail.com>2009-03-31 15:23:25 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2009-04-01 08:59:14 -0700
commitf4112de6b679d84bd9b9681c7504be7bdfb7c7d5 (patch)
treec9a5665b31e751e1d4255b8c35a6245d5abfa3eb /mm/highmem.c
parentmm: page_mkwrite change prototype to match fault: fix sysfs (diff)
downloadlinux-dev-f4112de6b679d84bd9b9681c7504be7bdfb7c7d5.tar.xz
linux-dev-f4112de6b679d84bd9b9681c7504be7bdfb7c7d5.zip
mm: introduce debug_kmap_atomic
x86 has debug_kmap_atomic_prot() which is error checking function for kmap_atomic. It is usefull for the other architectures, although it needs CONFIG_TRACE_IRQFLAGS_SUPPORT. This patch exposes it to the other architectures. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to '')
-rw-r--r--mm/highmem.c45
1 files changed, 45 insertions, 0 deletions
diff --git a/mm/highmem.c b/mm/highmem.c
index 910198037bf5..68eb1d9b63fa 100644
--- a/mm/highmem.c
+++ b/mm/highmem.c
@@ -422,3 +422,48 @@ void __init page_address_init(void)
}
#endif /* defined(CONFIG_HIGHMEM) && !defined(WANT_PAGE_VIRTUAL) */
+
+#if defined(CONFIG_DEBUG_HIGHMEM) && defined(CONFIG_TRACE_IRQFLAGS_SUPPORT)
+
+void debug_kmap_atomic(enum km_type type)
+{
+ static unsigned warn_count = 10;
+
+ if (unlikely(warn_count == 0))
+ return;
+
+ if (unlikely(in_interrupt())) {
+ if (in_irq()) {
+ if (type != KM_IRQ0 && type != KM_IRQ1 &&
+ type != KM_BIO_SRC_IRQ && type != KM_BIO_DST_IRQ &&
+ type != KM_BOUNCE_READ) {
+ WARN_ON(1);
+ warn_count--;
+ }
+ } else if (!irqs_disabled()) { /* softirq */
+ if (type != KM_IRQ0 && type != KM_IRQ1 &&
+ type != KM_SOFTIRQ0 && type != KM_SOFTIRQ1 &&
+ type != KM_SKB_SUNRPC_DATA &&
+ type != KM_SKB_DATA_SOFTIRQ &&
+ type != KM_BOUNCE_READ) {
+ WARN_ON(1);
+ warn_count--;
+ }
+ }
+ }
+
+ if (type == KM_IRQ0 || type == KM_IRQ1 || type == KM_BOUNCE_READ ||
+ type == KM_BIO_SRC_IRQ || type == KM_BIO_DST_IRQ) {
+ if (!irqs_disabled()) {
+ WARN_ON(1);
+ warn_count--;
+ }
+ } else if (type == KM_SOFTIRQ0 || type == KM_SOFTIRQ1) {
+ if (irq_count() == 0 && !irqs_disabled()) {
+ WARN_ON(1);
+ warn_count--;
+ }
+ }
+}
+
+#endif