From: Gabor Juhos Date: Sun, 12 Jan 2014 14:16:18 +0000 (+0000) Subject: mpc85xx: preallocate SPI transfer buffer X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=42fef4d421a3e3229aa26fc1ff69261862d00bc6;p=openwrt%2Fsvn-archive%2Farchive.git mpc85xx: preallocate SPI transfer buffer This helps to avoid high order alloction failures. Closes #14702. Signed-off-by: Gabor Juhos SVN-Revision: 39247 --- diff --git a/target/linux/mpc85xx/patches-3.10/210-spi-fsl-espi-preallocate-local-buffer.patch b/target/linux/mpc85xx/patches-3.10/210-spi-fsl-espi-preallocate-local-buffer.patch new file mode 100644 index 0000000000..cc0a718e90 --- /dev/null +++ b/target/linux/mpc85xx/patches-3.10/210-spi-fsl-espi-preallocate-local-buffer.patch @@ -0,0 +1,143 @@ +From: Gabor Juhos +Subject: spi-fsl-espi: avoid frequent high order allocations + +The driver allocates 64KiB of memory fro a local buffer before +each transfer and releases that afterwards. When the memory is +fragmented this allocation often fails and causes a warning like +this: + + kworker/u2:2: page allocation failure: order:4, mode:0x10c0d0 + CPU: 0 PID: 7011 Comm: kworker/u2:2 Not tainted 3.10.24 #1 + Workqueue: ffe07000.spi mpc8xxx_spi_work + Call Trace: + [c1c6dcf0] [c0006914] show_stack+0x50/0x170 (unreliable) + [c1c6dd30] [c0259858] dump_stack+0x24/0x34 + [c1c6dd40] [c00672e8] warn_alloc_failed+0x120/0x13c + [c1c6dd90] [c0069920] __alloc_pages_nodemask+0x574/0x5c8 + [c1c6de20] [c0069990] __get_free_pages+0x1c/0x4c + [c1c6de30] [c0185174] fsl_espi_do_one_msg+0x128/0x2a0 + [c1c6de90] [c0184290] mpc8xxx_spi_work+0x50/0x7c + [c1c6dea0] [c0037af8] process_one_work+0x208/0x30c + [c1c6dec0] [c00387a0] worker_thread+0x20c/0x308 + [c1c6def0] [c003de60] kthread+0xa4/0xa8 + [c1c6df40] [c000c4bc] ret_from_kernel_thread+0x5c/0x64 + + m25p80 spi0.0: error -12 reading SR + end_request: I/O error, dev mtdblock3, sector 680 + SQUASHFS error: squashfs_read_data failed to read block 0x54a4a + SQUASHFS error: Unable to read data cache entry [54a4a] + +Preallocate the buffer from the probe routine to avoid +this. + +Signed-off-by: Gabor Juhos +--- +--- a/drivers/spi/spi-fsl-espi.c ++++ b/drivers/spi/spi-fsl-espi.c +@@ -338,17 +338,13 @@ static void fsl_espi_do_trans(struct spi + static void fsl_espi_cmd_trans(struct spi_message *m, + struct fsl_espi_transfer *trans, u8 *rx_buff) + { ++ struct spi_device *spi = m->spi; ++ struct mpc8xxx_spi *mspi = spi_master_get_devdata(spi->master); + struct spi_transfer *t; +- u8 *local_buf; ++ u8 *local_buf = mspi->local_buf; + int i = 0; + struct fsl_espi_transfer *espi_trans = trans; + +- local_buf = kzalloc(SPCOM_TRANLEN_MAX, GFP_KERNEL); +- if (!local_buf) { +- espi_trans->status = -ENOMEM; +- return; +- } +- + list_for_each_entry(t, &m->transfers, transfer_list) { + if (t->tx_buf) { + memcpy(local_buf + i, t->tx_buf, t->len); +@@ -361,28 +357,23 @@ static void fsl_espi_cmd_trans(struct sp + fsl_espi_do_trans(m, espi_trans); + + espi_trans->actual_length = espi_trans->len; +- kfree(local_buf); + } + + static void fsl_espi_rw_trans(struct spi_message *m, + struct fsl_espi_transfer *trans, u8 *rx_buff) + { ++ struct spi_device *spi = m->spi; ++ struct mpc8xxx_spi *mspi = spi_master_get_devdata(spi->master); + struct fsl_espi_transfer *espi_trans = trans; + unsigned int n_tx = espi_trans->n_tx; + unsigned int n_rx = espi_trans->n_rx; + struct spi_transfer *t; +- u8 *local_buf; ++ u8 *local_buf = mspi->local_buf; + u8 *rx_buf = rx_buff; + unsigned int trans_len; + unsigned int addr; + int i, pos, loop; + +- local_buf = kzalloc(SPCOM_TRANLEN_MAX, GFP_KERNEL); +- if (!local_buf) { +- espi_trans->status = -ENOMEM; +- return; +- } +- + for (pos = 0, loop = 0; pos < n_rx; pos += trans_len, loop++) { + trans_len = n_rx - pos; + if (trans_len > SPCOM_TRANLEN_MAX - n_tx) +@@ -416,8 +407,6 @@ static void fsl_espi_rw_trans(struct spi + else + espi_trans->actual_length += espi_trans->len; + } +- +- kfree(local_buf); + } + + static void fsl_espi_do_one_msg(struct spi_message *m) +@@ -585,6 +574,7 @@ static irqreturn_t fsl_espi_irq(s32 irq, + static void fsl_espi_remove(struct mpc8xxx_spi *mspi) + { + iounmap(mspi->reg_base); ++ kfree(mspi->local_buf); + } + + static struct spi_master * fsl_espi_probe(struct device *dev, +@@ -615,10 +605,16 @@ static struct spi_master * fsl_espi_prob + mpc8xxx_spi->spi_do_one_msg = fsl_espi_do_one_msg; + mpc8xxx_spi->spi_remove = fsl_espi_remove; + ++ mpc8xxx_spi->local_buf = kzalloc(SPCOM_TRANLEN_MAX, GFP_KERNEL); ++ if (!mpc8xxx_spi->local_buf) { ++ ret = -ENOMEM; ++ goto err_probe; ++ } ++ + mpc8xxx_spi->reg_base = ioremap(mem->start, resource_size(mem)); + if (!mpc8xxx_spi->reg_base) { + ret = -ENOMEM; +- goto err_probe; ++ goto free_buf; + } + + reg_base = mpc8xxx_spi->reg_base; +@@ -661,6 +657,8 @@ unreg_master: + free_irq(mpc8xxx_spi->irq, mpc8xxx_spi); + free_irq: + iounmap(mpc8xxx_spi->reg_base); ++free_buf: ++ kfree(mpc8xxx_spi->local_buf); + err_probe: + spi_master_put(master); + err: +--- a/drivers/spi/spi-fsl-lib.h ++++ b/drivers/spi/spi-fsl-lib.h +@@ -30,6 +30,7 @@ struct mpc8xxx_spi { + void *rx; + #ifdef CONFIG_SPI_FSL_ESPI + int len; ++ u8 *local_buf; + #endif + + int subblock;