From a3ae39c060be57a4936d2c1d970e4d0c7d320d9c Mon Sep 17 00:00:00 2001 From: Andreas Herrmann <aherrman@de.ibm.com> Date: Thu, 27 Apr 2006 18:40:09 -0700 Subject: [PATCH] s390: qdio memory allocations Avoid memory allocation with GFP_KERNEL in qdio_establish/qdio_shutdown. Use memory pool instead. (Otherwise this can lead to an I/O stall where qdio waits for a free page and zfcp waits for end of error recovery in low memory situations.) Signed-off-by: Andreas Herrmann <aherrman@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org> --- drivers/s390/cio/qdio.c | 30 ++++++++++++++++++++++++------ 1 file changed, 24 insertions(+), 6 deletions(-) (limited to 'drivers/s390') diff --git a/drivers/s390/cio/qdio.c b/drivers/s390/cio/qdio.c index 814f9258ce0..a5bf272fe77 100644 --- a/drivers/s390/cio/qdio.c +++ b/drivers/s390/cio/qdio.c @@ -38,6 +38,7 @@ #include <linux/kernel.h> #include <linux/proc_fs.h> #include <linux/timer.h> +#include <linux/mempool.h> #include <asm/ccwdev.h> #include <asm/io.h> @@ -80,6 +81,8 @@ static int indicator_used[INDICATORS_PER_CACHELINE]; static __u32 * volatile indicators; static __u32 volatile spare_indicator; static atomic_t spare_indicator_usecount; +#define QDIO_MEMPOOL_SCSSC_ELEMENTS 2 +static mempool_t *qdio_mempool_scssc; static debug_info_t *qdio_dbf_setup; static debug_info_t *qdio_dbf_sbal; @@ -2304,7 +2307,7 @@ qdio_get_ssqd_information(struct qdio_irq *irq_ptr) QDIO_DBF_TEXT0(0,setup,"getssqd"); qdioac = 0; - ssqd_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA); + ssqd_area = mempool_alloc(qdio_mempool_scssc, GFP_ATOMIC); if (!ssqd_area) { QDIO_PRINT_WARN("Could not get memory for chsc. Using all " \ "SIGAs for sch x%x.\n", irq_ptr->schid.sch_no); @@ -2364,7 +2367,7 @@ qdio_get_ssqd_information(struct qdio_irq *irq_ptr) out: qdio_check_subchannel_qebsm(irq_ptr, qdioac, ssqd_area->sch_token); - free_page ((unsigned long) ssqd_area); + mempool_free(ssqd_area, qdio_mempool_scssc); irq_ptr->qdioac = qdioac; } @@ -2458,7 +2461,7 @@ tiqdio_set_subchannel_ind(struct qdio_irq *irq_ptr, int reset_to_zero) virt_to_phys((volatile void *)irq_ptr->dev_st_chg_ind); } - scssc_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA); + scssc_area = mempool_alloc(qdio_mempool_scssc, GFP_ATOMIC); if (!scssc_area) { QDIO_PRINT_WARN("No memory for setting indicators on " \ "subchannel 0.%x.%x.\n", @@ -2514,7 +2517,7 @@ tiqdio_set_subchannel_ind(struct qdio_irq *irq_ptr, int reset_to_zero) QDIO_DBF_HEX2(0,setup,&real_addr_dev_st_chg_ind,sizeof(unsigned long)); result = 0; out: - free_page ((unsigned long) scssc_area); + mempool_free(scssc_area, qdio_mempool_scssc); return result; } @@ -2543,7 +2546,7 @@ tiqdio_set_delay_target(struct qdio_irq *irq_ptr, unsigned long delay_target) if (!irq_ptr->is_thinint_irq) return -ENODEV; - scsscf_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA); + scsscf_area = mempool_alloc(qdio_mempool_scssc, GFP_ATOMIC); if (!scsscf_area) { QDIO_PRINT_WARN("No memory for setting delay target on " \ "subchannel 0.%x.%x.\n", @@ -2581,7 +2584,7 @@ tiqdio_set_delay_target(struct qdio_irq *irq_ptr, unsigned long delay_target) QDIO_DBF_HEX2(0,trace,&delay_target,sizeof(unsigned long)); result = 0; /* not critical */ out: - free_page ((unsigned long) scsscf_area); + mempool_free(scsscf_area, qdio_mempool_scssc); return result; } @@ -3780,6 +3783,16 @@ oom: return -ENOMEM; } +static void *qdio_mempool_alloc(gfp_t gfp_mask, void *size) +{ + return (void *) get_zeroed_page(gfp_mask|GFP_DMA); +} + +static void qdio_mempool_free(void *element, void *size) +{ + free_page((unsigned long) element); +} + static int __init init_QDIO(void) { @@ -3809,6 +3822,10 @@ init_QDIO(void) qdio_add_procfs_entry(); + qdio_mempool_scssc = mempool_create(QDIO_MEMPOOL_SCSSC_ELEMENTS, + qdio_mempool_alloc, + qdio_mempool_free, NULL); + if (tiqdio_check_chsc_availability()) QDIO_PRINT_ERR("Not all CHSCs supported. Continuing.\n"); @@ -3824,6 +3841,7 @@ cleanup_QDIO(void) qdio_remove_procfs_entry(); qdio_release_qdio_memory(); qdio_unregister_dbf_views(); + mempool_destroy(qdio_mempool_scssc); printk("qdio: %s: module removed\n",version); } -- cgit v1.2.3-70-g09d2