diff options
author | FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> | 2009-04-15 05:22:41 -0400 |
---|---|---|
committer | Ingo Molnar <mingo@elte.hu> | 2009-04-15 06:22:37 -0400 |
commit | e6a1a89d572c31b62d6dcf11a371c7323852d9b2 (patch) | |
tree | bca6ff9d83ae6820c3dd4270e165705c12b66f56 | |
parent | 7e05575c422d45f393c2d9b5900e97a30bf69bea (diff) |
dma-debug: add dma_debug_resize_entries() to adjust the number of dma_debug_entries
We use a static value for the number of dma_debug_entries. It can be
overwritten by a kernel command line option.
Some IOMMUs (e.g. GART) can't set an appropriate value by a kernel
command line option because they can't know such value until they
finish initializing up their hardware.
This patch adds dma_debug_resize_entries() enables IOMMUs to adjust
the number of dma_debug_entries anytime.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Joerg Roedel <joerg.roedel@amd.com>
Cc: fujita.tomonori@lab.ntt.co.jp
Cc: akpm@linux-foundation.org
LKML-Reference: <20090415182234R.fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
-rw-r--r-- | include/linux/dma-debug.h | 7 | ||||
-rw-r--r-- | lib/dma-debug.c | 72 |
2 files changed, 73 insertions, 6 deletions
diff --git a/include/linux/dma-debug.h b/include/linux/dma-debug.h index 28d53cb7b5a2..171ad8aedc83 100644 --- a/include/linux/dma-debug.h +++ b/include/linux/dma-debug.h | |||
@@ -32,6 +32,8 @@ extern void dma_debug_add_bus(struct bus_type *bus); | |||
32 | 32 | ||
33 | extern void dma_debug_init(u32 num_entries); | 33 | extern void dma_debug_init(u32 num_entries); |
34 | 34 | ||
35 | extern int dma_debug_resize_entries(u32 num_entries); | ||
36 | |||
35 | extern void debug_dma_map_page(struct device *dev, struct page *page, | 37 | extern void debug_dma_map_page(struct device *dev, struct page *page, |
36 | size_t offset, size_t size, | 38 | size_t offset, size_t size, |
37 | int direction, dma_addr_t dma_addr, | 39 | int direction, dma_addr_t dma_addr, |
@@ -91,6 +93,11 @@ static inline void dma_debug_init(u32 num_entries) | |||
91 | { | 93 | { |
92 | } | 94 | } |
93 | 95 | ||
96 | static inline int dma_debug_resize_entries(u32 num_entries) | ||
97 | { | ||
98 | return 0; | ||
99 | } | ||
100 | |||
94 | static inline void debug_dma_map_page(struct device *dev, struct page *page, | 101 | static inline void debug_dma_map_page(struct device *dev, struct page *page, |
95 | size_t offset, size_t size, | 102 | size_t offset, size_t size, |
96 | int direction, dma_addr_t dma_addr, | 103 | int direction, dma_addr_t dma_addr, |
diff --git a/lib/dma-debug.c b/lib/dma-debug.c index d3da7edc034f..5d61019330cd 100644 --- a/lib/dma-debug.c +++ b/lib/dma-debug.c | |||
@@ -85,6 +85,7 @@ static u32 show_num_errors = 1; | |||
85 | 85 | ||
86 | static u32 num_free_entries; | 86 | static u32 num_free_entries; |
87 | static u32 min_free_entries; | 87 | static u32 min_free_entries; |
88 | static u32 nr_total_entries; | ||
88 | 89 | ||
89 | /* number of preallocated entries requested by kernel cmdline */ | 90 | /* number of preallocated entries requested by kernel cmdline */ |
90 | static u32 req_entries; | 91 | static u32 req_entries; |
@@ -257,6 +258,21 @@ static void add_dma_entry(struct dma_debug_entry *entry) | |||
257 | put_hash_bucket(bucket, &flags); | 258 | put_hash_bucket(bucket, &flags); |
258 | } | 259 | } |
259 | 260 | ||
261 | static struct dma_debug_entry *__dma_entry_alloc(void) | ||
262 | { | ||
263 | struct dma_debug_entry *entry; | ||
264 | |||
265 | entry = list_entry(free_entries.next, struct dma_debug_entry, list); | ||
266 | list_del(&entry->list); | ||
267 | memset(entry, 0, sizeof(*entry)); | ||
268 | |||
269 | num_free_entries -= 1; | ||
270 | if (num_free_entries < min_free_entries) | ||
271 | min_free_entries = num_free_entries; | ||
272 | |||
273 | return entry; | ||
274 | } | ||
275 | |||
260 | /* struct dma_entry allocator | 276 | /* struct dma_entry allocator |
261 | * | 277 | * |
262 | * The next two functions implement the allocator for | 278 | * The next two functions implement the allocator for |
@@ -276,9 +292,7 @@ static struct dma_debug_entry *dma_entry_alloc(void) | |||
276 | goto out; | 292 | goto out; |
277 | } | 293 | } |
278 | 294 | ||
279 | entry = list_entry(free_entries.next, struct dma_debug_entry, list); | 295 | entry = __dma_entry_alloc(); |
280 | list_del(&entry->list); | ||
281 | memset(entry, 0, sizeof(*entry)); | ||
282 | 296 | ||
283 | #ifdef CONFIG_STACKTRACE | 297 | #ifdef CONFIG_STACKTRACE |
284 | entry->stacktrace.max_entries = DMA_DEBUG_STACKTRACE_ENTRIES; | 298 | entry->stacktrace.max_entries = DMA_DEBUG_STACKTRACE_ENTRIES; |
@@ -286,9 +300,6 @@ static struct dma_debug_entry *dma_entry_alloc(void) | |||
286 | entry->stacktrace.skip = 2; | 300 | entry->stacktrace.skip = 2; |
287 | save_stack_trace(&entry->stacktrace); | 301 | save_stack_trace(&entry->stacktrace); |
288 | #endif | 302 | #endif |
289 | num_free_entries -= 1; | ||
290 | if (num_free_entries < min_free_entries) | ||
291 | min_free_entries = num_free_entries; | ||
292 | 303 | ||
293 | out: | 304 | out: |
294 | spin_unlock_irqrestore(&free_entries_lock, flags); | 305 | spin_unlock_irqrestore(&free_entries_lock, flags); |
@@ -310,6 +321,53 @@ static void dma_entry_free(struct dma_debug_entry *entry) | |||
310 | spin_unlock_irqrestore(&free_entries_lock, flags); | 321 | spin_unlock_irqrestore(&free_entries_lock, flags); |
311 | } | 322 | } |
312 | 323 | ||
324 | int dma_debug_resize_entries(u32 num_entries) | ||
325 | { | ||
326 | int i, delta, ret = 0; | ||
327 | unsigned long flags; | ||
328 | struct dma_debug_entry *entry; | ||
329 | LIST_HEAD(tmp); | ||
330 | |||
331 | spin_lock_irqsave(&free_entries_lock, flags); | ||
332 | |||
333 | if (nr_total_entries < num_entries) { | ||
334 | delta = num_entries - nr_total_entries; | ||
335 | |||
336 | spin_unlock_irqrestore(&free_entries_lock, flags); | ||
337 | |||
338 | for (i = 0; i < delta; i++) { | ||
339 | entry = kzalloc(sizeof(*entry), GFP_KERNEL); | ||
340 | if (!entry) | ||
341 | break; | ||
342 | |||
343 | list_add_tail(&entry->list, &tmp); | ||
344 | } | ||
345 | |||
346 | spin_lock_irqsave(&free_entries_lock, flags); | ||
347 | |||
348 | list_splice(&tmp, &free_entries); | ||
349 | nr_total_entries += i; | ||
350 | num_free_entries += i; | ||
351 | } else { | ||
352 | delta = nr_total_entries - num_entries; | ||
353 | |||
354 | for (i = 0; i < delta && !list_empty(&free_entries); i++) { | ||
355 | entry = __dma_entry_alloc(); | ||
356 | kfree(entry); | ||
357 | } | ||
358 | |||
359 | nr_total_entries -= i; | ||
360 | } | ||
361 | |||
362 | if (nr_total_entries != num_entries) | ||
363 | ret = 1; | ||
364 | |||
365 | spin_unlock_irqrestore(&free_entries_lock, flags); | ||
366 | |||
367 | return ret; | ||
368 | } | ||
369 | EXPORT_SYMBOL(dma_debug_resize_entries); | ||
370 | |||
313 | /* | 371 | /* |
314 | * DMA-API debugging init code | 372 | * DMA-API debugging init code |
315 | * | 373 | * |
@@ -490,6 +548,8 @@ void dma_debug_init(u32 num_entries) | |||
490 | return; | 548 | return; |
491 | } | 549 | } |
492 | 550 | ||
551 | nr_total_entries = num_free_entries; | ||
552 | |||
493 | printk(KERN_INFO "DMA-API: debugging enabled by kernel config\n"); | 553 | printk(KERN_INFO "DMA-API: debugging enabled by kernel config\n"); |
494 | } | 554 | } |
495 | 555 | ||