From 76e8f93e8951779119de5e56a889ff30d2c4038e Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Tue, 21 Mar 2017 17:59:14 -0700 Subject: [PATCH] nfp: don't ignore return value of wait_event_interruptible When signal interrupts waiting for an area to become available we assume success. Pay attention to the return code. Unpack the code a little bit to make it more readable. Signed-off-by: Jakub Kicinski Signed-off-by: David S. Miller --- .../netronome/nfp/nfpcore/nfp_cppcore.c | 56 +++++++++++++------ 1 file changed, 38 insertions(+), 18 deletions(-) diff --git a/drivers/net/ethernet/netronome/nfp/nfpcore/nfp_cppcore.c b/drivers/net/ethernet/netronome/nfp/nfpcore/nfp_cppcore.c index 5189fedb0f4f..2e4796b52b84 100644 --- a/drivers/net/ethernet/netronome/nfp/nfpcore/nfp_cppcore.c +++ b/drivers/net/ethernet/netronome/nfp/nfpcore/nfp_cppcore.c @@ -411,9 +411,43 @@ nfp_cpp_area_alloc(struct nfp_cpp *cpp, u32 dest, */ void nfp_cpp_area_free(struct nfp_cpp_area *area) { + if (atomic_read(&area->refcount)) + nfp_warn(area->cpp, "Warning: freeing busy area\n"); nfp_cpp_area_put(area); } +static bool nfp_cpp_area_acquire_try(struct nfp_cpp_area *area, int *status) +{ + *status = area->cpp->op->area_acquire(area); + + return *status != -EAGAIN; +} + +static int __nfp_cpp_area_acquire(struct nfp_cpp_area *area) +{ + int err, status; + + if (atomic_inc_return(&area->refcount) > 1) + return 0; + + if (!area->cpp->op->area_acquire) + return 0; + + err = wait_event_interruptible(area->cpp->waitq, + nfp_cpp_area_acquire_try(area, &status)); + if (!err) + err = status; + if (err) { + nfp_warn(area->cpp, "Warning: area wait failed: %d\n", err); + atomic_dec(&area->refcount); + return err; + } + + nfp_cpp_area_get(area); + + return 0; +} + /** * nfp_cpp_area_acquire() - lock down a CPP area for access * @area: CPP area handle @@ -425,27 +459,13 @@ void nfp_cpp_area_free(struct nfp_cpp_area *area) */ int nfp_cpp_area_acquire(struct nfp_cpp_area *area) { - mutex_lock(&area->mutex); - if (atomic_inc_return(&area->refcount) == 1) { - int (*a_a)(struct nfp_cpp_area *); - - a_a = area->cpp->op->area_acquire; - if (a_a) { - int err; + int ret; - wait_event_interruptible(area->cpp->waitq, - (err = a_a(area)) != -EAGAIN); - if (err < 0) { - atomic_dec(&area->refcount); - mutex_unlock(&area->mutex); - return err; - } - } - } + mutex_lock(&area->mutex); + ret = __nfp_cpp_area_acquire(area); mutex_unlock(&area->mutex); - nfp_cpp_area_get(area); - return 0; + return ret; } /** -- 2.20.1