firewire: ohci: reorder struct fw_ohci for better cache efficiency
authorStefan Richter <stefanr@s5r6.in-berlin.de>
Sun, 21 Feb 2010 16:57:32 +0000 (17:57 +0100)
committerStefan Richter <stefanr@s5r6.in-berlin.de>
Wed, 24 Feb 2010 19:36:55 +0000 (20:36 +0100)
The config_rom struct members are only accessed during relatively
infrequent self-ID-complete interrupts and only if the local config ROM
was changed, while the ar_, at_, ir_, it_ members are used very
frequently during I/O.  Hence move the config_rom members further down.

More importantly, make the huge self_id_buffer member the last one; this
is only accessed in self-ID-complete interrupts.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
drivers/firewire/ohci.c

index 047331e59b31d3fbedb6aa8842b96fa99b101669..39ddb620cad5497320161e8f5bc7beeda71b1681 100644 (file)
@@ -166,9 +166,6 @@ struct fw_ohci {
        struct fw_card card;
 
        __iomem char *registers;
-       dma_addr_t self_id_bus;
-       __le32 *self_id_cpu;
-       struct tasklet_struct bus_reset_tasklet;
        int node_id;
        int generation;
        int request_generation; /* for timestamping incoming requests */
@@ -182,14 +179,6 @@ struct fw_ohci {
         * this driver with this lock held.
         */
        spinlock_t lock;
-       u32 self_id_buffer[512];
-
-       /* Config rom buffers */
-       __be32 *config_rom;
-       dma_addr_t config_rom_bus;
-       __be32 *next_config_rom;
-       dma_addr_t next_config_rom_bus;
-       __be32 next_header;
 
        struct ar_context ar_request_ctx;
        struct ar_context ar_response_ctx;
@@ -201,6 +190,18 @@ struct fw_ohci {
        u64 ir_context_channels;
        u32 ir_context_mask;
        struct iso_context *ir_context_list;
+
+       __be32    *config_rom;
+       dma_addr_t config_rom_bus;
+       __be32    *next_config_rom;
+       dma_addr_t next_config_rom_bus;
+       __be32     next_header;
+
+       __le32    *self_id_cpu;
+       dma_addr_t self_id_bus;
+       struct tasklet_struct bus_reset_tasklet;
+
+       u32 self_id_buffer[512];
 };
 
 static inline struct fw_ohci *fw_ohci(struct fw_card *card)