From: Dave Olson Date: Fri, 20 Jul 2007 19:50:55 +0000 (-0700) Subject: IB/ipath: Remove unsafe fastrcvint code from interrupt handler X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=f17fddc9e266281bbb4d384b031e1521e1f2510e;p=GitHub%2Fexynos8895%2Fandroid_kernel_samsung_universal8895.git IB/ipath: Remove unsafe fastrcvint code from interrupt handler The fastrcvint code's purpose was to avoid reading the interrupt status if kernel packets were in the receive queue (to reduce overhead). Because intstatus was not read, we could miss the error interrupt bit indicating freeze mode, since it only delivers a single interrupt, even if still pending after intclear is written. This patch removes that unsafe optimization. Signed-off-by: Dave Olson Signed-off-by: Roland Dreier --- diff --git a/drivers/infiniband/hw/ipath/ipath_common.h b/drivers/infiniband/hw/ipath/ipath_common.h index b4b786d0dfca..6ad822c35930 100644 --- a/drivers/infiniband/hw/ipath/ipath_common.h +++ b/drivers/infiniband/hw/ipath/ipath_common.h @@ -100,8 +100,7 @@ struct infinipath_stats { __u64 sps_hwerrs; /* number of times IB link changed state unexpectedly */ __u64 sps_iblink; - /* kernel receive interrupts that didn't read intstat */ - __u64 sps_fastrcvint; + __u64 sps_unused; /* was fastrcvint, no longer implemented */ /* number of kernel (port0) packets received */ __u64 sps_port0pkts; /* number of "ethernet" packets sent by driver */ diff --git a/drivers/infiniband/hw/ipath/ipath_intr.c b/drivers/infiniband/hw/ipath/ipath_intr.c index 1fd91c59f246..cba2041bb0b1 100644 --- a/drivers/infiniband/hw/ipath/ipath_intr.c +++ b/drivers/infiniband/hw/ipath/ipath_intr.c @@ -1002,7 +1002,6 @@ irqreturn_t ipath_intr(int irq, void *data) u32 istat, chk0rcv = 0; ipath_err_t estat = 0; irqreturn_t ret; - u32 oldhead, curtail; static unsigned unexpected = 0; static const u32 port0rbits = (1U<ipath_port0head; - curtail = (u32)le64_to_cpu(*dd->ipath_hdrqtailptr); - if (oldhead != curtail) { - if (dd->ipath_flags & IPATH_GPIO_INTR) { - ipath_write_kreg(dd, dd->ipath_kregs->kr_gpio_clear, - (u64) (1 << IPATH_GPIO_PORT0_BIT)); - istat = port0rbits | INFINIPATH_I_GPIO; - } - else - istat = port0rbits; - ipath_write_kreg(dd, dd->ipath_kregs->kr_intclear, istat); - ipath_kreceive(dd); - if (oldhead != dd->ipath_port0head) { - ipath_stats.sps_fastrcvint++; - goto done; - } - } - istat = ipath_read_kreg32(dd, dd->ipath_kregs->kr_intstatus); if (unlikely(!istat)) { @@ -1225,7 +1194,6 @@ irqreturn_t ipath_intr(int irq, void *data) handle_layer_pioavail(dd); } -done: ret = IRQ_HANDLED; bail: