| Message ID | alpine.LNX.2.00.1109110038500.5327@nippy.intranet |
|---|---|
| State | Not Applicable, archived |
| Delegated to: | David Miller |
| Headers | show |
From: Finn Thain <fthain@telegraphics.com.au> Date: Sun, 11 Sep 2011 01:01:34 +1000 (EST) > Mutual exclusion is redundant here because all the paths in the call graph > leading to esp_driver_ops.send_dma_cmd() happen under spin_lock_irqsave/ > spin_lock_irqrestore. Remove it. > > Tested on a Mac Quadra 660av and a Mac LC 630. > > Signed-off-by: Finn Thain <fthain@telegraphics.com.au> This patch should be CC:'d to linux-scsi not netdev I understand how the networking maintainer is very responsive and the SCSI maintainer generally takes forever, so your Freudian slip will go unjudged :-) -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Index: linux-m68k/drivers/scsi/mac_esp.c =================================================================== --- linux-m68k.orig/drivers/scsi/mac_esp.c 2011-08-28 00:33:13.000000000 +1000 +++ linux-m68k/drivers/scsi/mac_esp.c 2011-08-28 00:35:48.000000000 +1000 @@ -230,9 +230,6 @@ static void mac_esp_send_pdma_cmd(struct u32 dma_count, int write, u8 cmd) { struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp); - unsigned long flags; - - local_irq_save(flags); mep->error = 0; @@ -270,8 +267,6 @@ static void mac_esp_send_pdma_cmd(struct esp_count = n; } } while (esp_count); - - local_irq_restore(flags); } /* @@ -353,8 +348,6 @@ static void mac_esp_send_pio_cmd(struct struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp); u8 *fifo = esp->regs + ESP_FDATA * 16; - disable_irq(esp->host->irq); - cmd &= ~ESP_CMD_DMA; mep->error = 0; @@ -431,8 +424,6 @@ static void mac_esp_send_pio_cmd(struct scsi_esp_cmd(esp, ESP_CMD_TI); } } - - enable_irq(esp->host->irq); } static int mac_esp_irq_pending(struct esp *esp)
Mutual exclusion is redundant here because all the paths in the call graph leading to esp_driver_ops.send_dma_cmd() happen under spin_lock_irqsave/ spin_lock_irqrestore. Remove it. Tested on a Mac Quadra 660av and a Mac LC 630. Signed-off-by: Finn Thain <fthain@telegraphics.com.au> --- Part of this patch relates to Geert's m68k generic hard irq conversion work. Under genirq, the disable_irq() in mac_esp leads to deadlock. It wasn't a problem before because the m68k disable_irq() implementation is equivalent to genirq's disable_irq_nosync(). -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html