From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nathan Chancellor Subject: Re: Clang warning in drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c Date: Wed, 20 Mar 2019 08:44:50 -0700 Message-ID: <20190320154450.GA20310@archlinux-ryzen> References: <20190320005406.GA16412@archlinux-ryzen> <20190320043440.GA23335@archlinux-ryzen> <63518f1f-b808-77b0-aac6-ee1ece669c4b@amd.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Stephen Hines Cc: "Koenig, Christian" , "Pan, Xinhui" , "Deucher, Alexander" , "Zhou, David(ChunMing)" , "amd-gfx@lists.freedesktop.org" , "dri-devel@lists.freedesktop.org" , "linux-kernel@vger.kernel.org" , "clang-built-linux@googlegroups.com" List-Id: dri-devel@lists.freedesktop.org On Wed, Mar 20, 2019 at 07:58:09AM -0700, Stephen Hines wrote: > Why are there 2 different enums for this same thing at all? By casting, you > are reducing type safety in the kernel, which can cause bugs later (should > the two enums diverge in encoding). In my opinion, the proper solution is > to remove one of the enums or provide an explicit helper that does the > conversion (along with assertions for handling any unexpected cases). The > helper function should not be doing a direct cast, since a bug could change > the integer value of one (or both) of these enums so that they don't match > up. > > Thanks, > Steve > Indeed, I would suggest something like this (if this was to be a build time error, this would need to be a macro instead of a function): diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c index a71668b8a7d0..451478cf4f35 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c @@ -541,13 +541,13 @@ int amdgpu_ras_feature_enable(struct amdgpu_device *adev, if (!enable) { info.disable_features = (struct ta_ras_disable_features_input) { - .block_id = head->block, - .error_type = head->type, + .block_id = amdgpu_ras_block_to_ta(head->block), + .error_type = amdgpu_ras_error_to_ta(head->type), }; } else { info.enable_features = (struct ta_ras_enable_features_input) { - .block_id = head->block, - .error_type = head->type, + .block_id = amdgpu_ras_block_to_ta(head->block), + .error_type = amdgpu_ras_error_to_ta(head->type), }; } @@ -647,8 +647,8 @@ int amdgpu_ras_error_inject(struct amdgpu_device *adev, { struct ras_manager *obj = amdgpu_ras_find_obj(adev, &info->head); struct ta_ras_trigger_error_input block_info = { - .block_id = info->head.block, - .inject_error_type = info->head.type, + .block_id = amdgpu_ras_block_to_ta(info->head.block), + .inject_error_type = amdgpu_ras_error_to_ta(info->head.type), .sub_block_index = info->head.sub_block_index, .address = info->address, .value = info->value, diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ras.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_ras.h index 7a35316baab0..c8576ab6e057 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ras.h +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ras.h @@ -197,6 +197,64 @@ static inline int amdgpu_ras_reset_gpu(struct amdgpu_device *adev, return 0; } +static inline enum ta_ras_block +amdgpu_ras_block_to_ta(enum amdgpu_ras_block block) +{ + switch (block) { + case AMDGPU_RAS_BLOCK__UMC: + return TA_RAS_BLOCK__UMC; + case AMDGPU_RAS_BLOCK__SDMA: + return TA_RAS_BLOCK__SDMA; + case AMDGPU_RAS_BLOCK__GFX: + return TA_RAS_BLOCK__GFX; + case AMDGPU_RAS_BLOCK__MMHUB: + return TA_RAS_BLOCK__MMHUB; + case AMDGPU_RAS_BLOCK__ATHUB: + return TA_RAS_BLOCK__ATHUB; + case AMDGPU_RAS_BLOCK__PCIE_BIF: + return TA_RAS_BLOCK__PCIE_BIF; + case AMDGPU_RAS_BLOCK__HDP: + return TA_RAS_BLOCK__HDP; + case AMDGPU_RAS_BLOCK__XGMI_WAFL: + return TA_RAS_BLOCK__XGMI_WAFL; + case AMDGPU_RAS_BLOCK__DF: + return TA_RAS_BLOCK__DF; + case AMDGPU_RAS_BLOCK__SMN: + return TA_RAS_BLOCK__SMN; + case AMDGPU_RAS_BLOCK__SEM: + return TA_RAS_BLOCK__SEM; + case AMDGPU_RAS_BLOCK__MP0: + return TA_RAS_BLOCK__MP0; + case AMDGPU_RAS_BLOCK__MP1: + return TA_RAS_BLOCK__MP1; + case AMDGPU_RAS_BLOCK__FUSE: + return TA_RAS_BLOCK__FUSE; + default: + WARN(1, "amdgpu_ras_block_to_ta fell through with a value of %d\n", block); + return TA_RAS_BLOCK__UMC; + } +} + +static inline enum ta_ras_error_type +amdgpu_ras_error_to_ta(enum amdgpu_ras_error_type error) +{ + switch (error) { + case AMDGPU_RAS_ERROR__NONE: + return TA_RAS_ERROR__NONE; + case AMDGPU_RAS_ERROR__PARITY: + return TA_RAS_ERROR__PARITY; + case AMDGPU_RAS_ERROR__SINGLE_CORRECTABLE: + return TA_RAS_ERROR__SINGLE_CORRECTABLE; + case AMDGPU_RAS_ERROR__MULTI_UNCORRECTABLE: + return TA_RAS_ERROR__MULTI_UNCORRECTABLE; + case AMDGPU_RAS_ERROR__POISON: + return TA_RAS_ERROR__POISON; + default: + WARN(1, "amdgpu_ras_error_to_ta fell through with a value of %d\n", error); + return TA_RAS_ERROR__NONE; + } +} + /* called in ip_init and ip_fini */ int amdgpu_ras_init(struct amdgpu_device *adev); void amdgpu_ras_post_init(struct amdgpu_device *adev); > On Wed, Mar 20, 2019 at 2:37 AM Koenig, Christian > wrote: > > > Am 20.03.19 um 05:34 schrieb Nathan Chancellor: > > > On Wed, Mar 20, 2019 at 01:31:27AM +0000, Pan, Xinhui wrote: > > >> these two enumerated types are same for now. both of them might change > > in the future. > > >> > > >> I have not used clang, but would .block_id = (int)head->block fix > > your warning? If such change is acceptable, I can make one then. > > >> > > >> Thanks > > >> xinhui > > >> > > >> > > >> -----Original Message----- > > >> From: Nathan Chancellor > > >> Sent: 2019年3月20日 8:54 > > >> To: Deucher, Alexander ; Koenig, Christian < > > Christian.Koenig@amd.com>; Zhou, David(ChunMing) ; > > Pan, Xinhui > > >> Cc: amd-gfx@lists.freedesktop.org; dri-devel@lists.freedesktop.org; > > linux-kernel@vger.kernel.org; clang-built-linux@googlegroups.com > > >> Subject: Clang warning in drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c > > >> > > >> Hi all, > > >> > > >> The introduction of this file in commit dbd249c24427 ("drm/amdgpu: add > > amdgpu_ras.c to support ras (v2)") introduces the following Clang > > >> warnings: > > >> > > >> drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c:544:23: warning: implicit > > conversion from enumeration type 'enum amdgpu_ras_block' to different > > enumeration type 'enum ta_ras_block' [-Wenum-conversion] > > >> .block_id = head->block, > > >> ~~~~~~^~~~~ > > >> drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c:545:24: warning: implicit > > conversion from enumeration type 'enum amdgpu_ras_error_type' to different > > enumeration type 'enum ta_ras_error_type' [-Wenum-conversion] > > >> .error_type = head->type, > > >> ~~~~~~^~~~ > > >> drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c:549:23: warning: implicit > > conversion from enumeration type 'enum amdgpu_ras_block' to different > > enumeration type 'enum ta_ras_block' [-Wenum-conversion] > > >> .block_id = head->block, > > >> ~~~~~~^~~~~ > > >> drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c:550:24: warning: implicit > > conversion from enumeration type 'enum amdgpu_ras_error_type' to different > > enumeration type 'enum ta_ras_error_type' [-Wenum-conversion] > > >> .error_type = head->type, > > >> ~~~~~~^~~~ > > >> drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c:650:26: warning: implicit > > conversion from enumeration type 'enum amdgpu_ras_block' to different > > enumeration type 'enum ta_ras_block' [-Wenum-conversion] > > >> .block_id = info->head.block, > > >> ~~~~~~~~~~~^~~~~ > > >> drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c:651:35: warning: implicit > > conversion from enumeration type 'enum amdgpu_ras_error_type' to different > > enumeration type 'enum ta_ras_error_type' [-Wenum-conversion] > > >> .inject_error_type = info->head.type, > > >> ~~~~~~~~~~~^~~~ > > >> 6 warnings generated. > > >> > > >> Normally, I would sent a fix for this myself but I am not entirely sure > > why these two enumerated types exist when one would do since they have the > > same values minus the prefix. In fact, the ta_ras_{block,error_type} values > > are never used aside from being defined. Some clarification would be > > appreciated. > > >> > > >> Thank you, > > >> Nathan > > > Hi Xinhui, > > > > > > Yes, explicitly casting these six spots to int would resolve this > > > warning. > > > > Another question is if it is such a good idea to just silence the warning? > > > > Maybe add a amdgpu_ras_error_to_ta() helper to do this casting? > > > > When the enums drift away from each other then we can still add warnings > > to that helper to make sure we don't accidentally cast invalid values > > around. > > > > Regards, > > Christian. > > > > > > > > Thank you for the quick response! > > > Nathan > > > > -- > > You received this message because you are subscribed to the Google Groups > > "Clang Built Linux" group. > > To unsubscribe from this group and stop receiving emails from it, send an > > email to clang-built-linux+unsubscribe@googlegroups.com. > > To post to this group, send email to clang-built-linux@googlegroups.com. > > To view this discussion on the web visit > > https://groups.google.com/d/msgid/clang-built-linux/63518f1f-b808-77b0-aac6-ee1ece669c4b%40amd.com > > . > > For more options, visit https://groups.google.com/d/optout. > >