From: Anju T Sudhakar <anju@xxxxxxxxxxxxxxxxxx> [ Upstream commit 48e626ac85b43cc589dd1b3b8004f7f85f03544d ] export_imc_mode_and_cmd() function which creates the debugfs interface for imc-mode and imc-command, is invoked when each nest pmu units is registered. When the first nest pmu unit is registered, export_imc_mode_and_cmd() creates 'imc' directory under `/debug/powerpc/`. In the subsequent invocations debugfs_create_dir() function returns, since the directory already exists. The recent commit <c33d442328f55> (debugfs: make error message a bit more verbose), throws a warning if we try to invoke `debugfs_create_dir()` with an already existing directory name. Address this warning by making the debugfs directory registration in the opal_imc_counters_probe() function, i.e invoke export_imc_mode_and_cmd() function from the probe function. Signed-off-by: Anju T Sudhakar <anju@xxxxxxxxxxxxxxxxxx> Tested-by: Nageswara R Sastry <nasastry@xxxxxxxxxx> Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20191127072035.4283-1-anju@xxxxxxxxxxxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- arch/powerpc/platforms/powernv/opal-imc.c | 39 ++++++++++------------- 1 file changed, 16 insertions(+), 23 deletions(-) diff --git a/arch/powerpc/platforms/powernv/opal-imc.c b/arch/powerpc/platforms/powernv/opal-imc.c index 7ccc5c85c74e..000b350d4060 100644 --- a/arch/powerpc/platforms/powernv/opal-imc.c +++ b/arch/powerpc/platforms/powernv/opal-imc.c @@ -59,10 +59,6 @@ static void export_imc_mode_and_cmd(struct device_node *node, imc_debugfs_parent = debugfs_create_dir("imc", powerpc_debugfs_root); - /* - * Return here, either because 'imc' directory already exists, - * Or failed to create a new one. - */ if (!imc_debugfs_parent) return; @@ -135,7 +131,6 @@ static int imc_get_mem_addr_nest(struct device_node *node, } pmu_ptr->imc_counter_mmaped = true; - export_imc_mode_and_cmd(node, pmu_ptr); kfree(base_addr_arr); kfree(chipid_arr); return 0; @@ -151,7 +146,7 @@ static int imc_get_mem_addr_nest(struct device_node *node, * and domain as the inputs. * Allocates memory for the struct imc_pmu, sets up its domain, size and offsets */ -static int imc_pmu_create(struct device_node *parent, int pmu_index, int domain) +static struct imc_pmu *imc_pmu_create(struct device_node *parent, int pmu_index, int domain) { int ret = 0; struct imc_pmu *pmu_ptr; @@ -159,27 +154,23 @@ static int imc_pmu_create(struct device_node *parent, int pmu_index, int domain) /* Return for unknown domain */ if (domain < 0) - return -EINVAL; + return NULL; /* memory for pmu */ pmu_ptr = kzalloc(sizeof(*pmu_ptr), GFP_KERNEL); if (!pmu_ptr) - return -ENOMEM; + return NULL; /* Set the domain */ pmu_ptr->domain = domain; ret = of_property_read_u32(parent, "size", &pmu_ptr->counter_mem_size); - if (ret) { - ret = -EINVAL; + if (ret) goto free_pmu; - } if (!of_property_read_u32(parent, "offset", &offset)) { - if (imc_get_mem_addr_nest(parent, pmu_ptr, offset)) { - ret = -EINVAL; + if (imc_get_mem_addr_nest(parent, pmu_ptr, offset)) goto free_pmu; - } } /* Function to register IMC pmu */ @@ -190,14 +181,14 @@ static int imc_pmu_create(struct device_node *parent, int pmu_index, int domain) if (pmu_ptr->domain == IMC_DOMAIN_NEST) kfree(pmu_ptr->mem_info); kfree(pmu_ptr); - return ret; + return NULL; } - return 0; + return pmu_ptr; free_pmu: kfree(pmu_ptr); - return ret; + return NULL; } static void disable_nest_pmu_counters(void) @@ -254,6 +245,7 @@ int get_max_nest_dev(void) static int opal_imc_counters_probe(struct platform_device *pdev) { struct device_node *imc_dev = pdev->dev.of_node; + struct imc_pmu *pmu; int pmu_count = 0, domain; bool core_imc_reg = false, thread_imc_reg = false; u32 type; @@ -269,6 +261,7 @@ static int opal_imc_counters_probe(struct platform_device *pdev) } for_each_compatible_node(imc_dev, NULL, IMC_DTB_UNIT_COMPAT) { + pmu = NULL; if (of_property_read_u32(imc_dev, "type", &type)) { pr_warn("IMC Device without type property\n"); continue; @@ -300,9 +293,13 @@ static int opal_imc_counters_probe(struct platform_device *pdev) break; } - if (!imc_pmu_create(imc_dev, pmu_count, domain)) { - if (domain == IMC_DOMAIN_NEST) + pmu = imc_pmu_create(imc_dev, pmu_count, domain); + if (pmu != NULL) { + if (domain == IMC_DOMAIN_NEST) { + if (!imc_debugfs_parent) + export_imc_mode_and_cmd(imc_dev, pmu); pmu_count++; + } if (domain == IMC_DOMAIN_CORE) core_imc_reg = true; if (domain == IMC_DOMAIN_THREAD) @@ -310,10 +307,6 @@ static int opal_imc_counters_probe(struct platform_device *pdev) } } - /* If none of the nest units are registered, remove debugfs interface */ - if (pmu_count == 0) - debugfs_remove_recursive(imc_debugfs_parent); - /* If core imc is not registered, unregister thread-imc */ if (!core_imc_reg && thread_imc_reg) unregister_thread_imc(); -- 2.25.1
