From: "Leizhen (ThunderTown)" <thunder.leizhen@huawei.com> To: Will Deacon <will@kernel.org> Cc: Robin Murphy <robin.murphy@arm.com>, iommu <iommu@lists.linux-foundation.org>, linux-arm-kernel <linux-arm-kernel@lists.infradead.org> Subject: Re: [PATCH 1/1] iommu/arm-smmu-v3: remove unnecessary oom message Date: Tue, 15 Jun 2021 19:22:10 +0800 [thread overview] Message-ID: <2a0b7f37-156a-775f-ade4-015cade472c6@huawei.com> (raw) In-Reply-To: <20210611103220.GB15274@willie-the-truck> On 2021/6/11 18:32, Will Deacon wrote: > On Wed, Jun 09, 2021 at 08:54:38PM +0800, Zhen Lei wrote: >> Fixes scripts/checkpatch.pl warning: >> WARNING: Possible unnecessary 'out of memory' message >> >> Remove it can help us save a bit of memory. >> >> Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> >> --- >> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 8 ++------ >> 1 file changed, 2 insertions(+), 6 deletions(-) >> >> diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c >> index 2ddc3cd5a7d1..fd7c55b44881 100644 >> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c >> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c >> @@ -2787,10 +2787,8 @@ static int arm_smmu_init_l1_strtab(struct arm_smmu_device *smmu) >> void *strtab = smmu->strtab_cfg.strtab; >> >> cfg->l1_desc = devm_kzalloc(smmu->dev, size, GFP_KERNEL); >> - if (!cfg->l1_desc) { >> - dev_err(smmu->dev, "failed to allocate l1 stream table desc\n"); >> + if (!cfg->l1_desc) > > What error do you get if devm_kzalloc() fails? I'd like to make sure it's > easy to track down _which_ allocation failed in that case -- does it give > you a line number, for example? When devm_kzalloc() fails, the OOM information is printed. No line number information, but the size(order) and call stack is printed. It doesn't matter which allocation failed, the failure is caused by insufficient system memory rather than the fault of the SMMU driver. Therefore, the current printing is not helpful for locating the problem of insufficient memory. After all, when memory allocation fails, the SMMU driver cannot work at a lower specification. [ 44.126661] swapper/0 invoked oom-killer: gfp_mask=0x40cc0(GFP_KERNEL|__GFP_COMP), order=1, oom_score_adj=0 [ 44.136381] CPU: 26 PID: 1 Comm: swapper/0 Not tainted 5.13.0-rc6-00001-g0d973bf828c8 #1 [ 44.144436] Hardware name: Huawei TaiShan 2280 V2/BC82AMDC, BIOS 2280-V2 CS V3.B220.02 03/27/2020 [ 44.153266] Call trace: [ 44.155703] dump_backtrace+0x0/0x1c0 [ 44.159355] show_stack+0x18/0x68 [ 44.162658] dump_stack+0xd8/0x134 [ 44.166047] dump_header+0x44/0x208 [ 44.169524] out_of_memory+0x530/0x580 [ 44.173256] __alloc_pages_slowpath.constprop.120+0x85c/0xac0 [ 44.178976] __alloc_pages+0x238/0x300 [ 44.182709] allocate_slab+0x3bc/0x3d8 [ 44.186440] ___slab_alloc+0x508/0x6b0 [ 44.190172] __slab_alloc.isra.100+0x2c/0x58 [ 44.194422] __kmalloc_node_track_caller+0x138/0x2e8 [ 44.199365] devm_kmalloc+0x58/0x100 [ 44.202926] arm_smmu_device_probe+0x858/0x1150 [ 44.207437] platform_probe+0x68/0xe0 > > Will > > . > _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
WARNING: multiple messages have this Message-ID (diff)
From: "Leizhen (ThunderTown)" <thunder.leizhen@huawei.com> To: Will Deacon <will@kernel.org> Cc: Robin Murphy <robin.murphy@arm.com>, linux-arm-kernel <linux-arm-kernel@lists.infradead.org>, Joerg Roedel <joro@8bytes.org>, iommu <iommu@lists.linux-foundation.org> Subject: Re: [PATCH 1/1] iommu/arm-smmu-v3: remove unnecessary oom message Date: Tue, 15 Jun 2021 19:22:10 +0800 [thread overview] Message-ID: <2a0b7f37-156a-775f-ade4-015cade472c6@huawei.com> (raw) In-Reply-To: <20210611103220.GB15274@willie-the-truck> On 2021/6/11 18:32, Will Deacon wrote: > On Wed, Jun 09, 2021 at 08:54:38PM +0800, Zhen Lei wrote: >> Fixes scripts/checkpatch.pl warning: >> WARNING: Possible unnecessary 'out of memory' message >> >> Remove it can help us save a bit of memory. >> >> Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> >> --- >> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 8 ++------ >> 1 file changed, 2 insertions(+), 6 deletions(-) >> >> diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c >> index 2ddc3cd5a7d1..fd7c55b44881 100644 >> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c >> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c >> @@ -2787,10 +2787,8 @@ static int arm_smmu_init_l1_strtab(struct arm_smmu_device *smmu) >> void *strtab = smmu->strtab_cfg.strtab; >> >> cfg->l1_desc = devm_kzalloc(smmu->dev, size, GFP_KERNEL); >> - if (!cfg->l1_desc) { >> - dev_err(smmu->dev, "failed to allocate l1 stream table desc\n"); >> + if (!cfg->l1_desc) > > What error do you get if devm_kzalloc() fails? I'd like to make sure it's > easy to track down _which_ allocation failed in that case -- does it give > you a line number, for example? When devm_kzalloc() fails, the OOM information is printed. No line number information, but the size(order) and call stack is printed. It doesn't matter which allocation failed, the failure is caused by insufficient system memory rather than the fault of the SMMU driver. Therefore, the current printing is not helpful for locating the problem of insufficient memory. After all, when memory allocation fails, the SMMU driver cannot work at a lower specification. [ 44.126661] swapper/0 invoked oom-killer: gfp_mask=0x40cc0(GFP_KERNEL|__GFP_COMP), order=1, oom_score_adj=0 [ 44.136381] CPU: 26 PID: 1 Comm: swapper/0 Not tainted 5.13.0-rc6-00001-g0d973bf828c8 #1 [ 44.144436] Hardware name: Huawei TaiShan 2280 V2/BC82AMDC, BIOS 2280-V2 CS V3.B220.02 03/27/2020 [ 44.153266] Call trace: [ 44.155703] dump_backtrace+0x0/0x1c0 [ 44.159355] show_stack+0x18/0x68 [ 44.162658] dump_stack+0xd8/0x134 [ 44.166047] dump_header+0x44/0x208 [ 44.169524] out_of_memory+0x530/0x580 [ 44.173256] __alloc_pages_slowpath.constprop.120+0x85c/0xac0 [ 44.178976] __alloc_pages+0x238/0x300 [ 44.182709] allocate_slab+0x3bc/0x3d8 [ 44.186440] ___slab_alloc+0x508/0x6b0 [ 44.190172] __slab_alloc.isra.100+0x2c/0x58 [ 44.194422] __kmalloc_node_track_caller+0x138/0x2e8 [ 44.199365] devm_kmalloc+0x58/0x100 [ 44.202926] arm_smmu_device_probe+0x858/0x1150 [ 44.207437] platform_probe+0x68/0xe0 > > Will > > . > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2021-06-15 11:22 UTC|newest] Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top 2021-06-09 12:54 [PATCH 1/1] iommu/arm-smmu-v3: remove unnecessary oom message Zhen Lei 2021-06-09 12:54 ` Zhen Lei 2021-06-11 10:32 ` Will Deacon 2021-06-11 10:32 ` Will Deacon 2021-06-15 11:22 ` Leizhen (ThunderTown) [this message] 2021-06-15 11:22 ` Leizhen (ThunderTown) 2021-06-15 11:34 ` Will Deacon 2021-06-15 11:34 ` Will Deacon 2021-06-15 11:36 ` Will Deacon 2021-06-15 11:36 ` Will Deacon 2021-06-15 11:51 ` Robin Murphy 2021-06-15 11:51 ` Robin Murphy 2021-06-15 11:55 ` Will Deacon 2021-06-15 11:55 ` Will Deacon 2021-06-16 1:47 ` Leizhen (ThunderTown) 2021-06-16 1:47 ` Leizhen (ThunderTown) 2021-06-16 10:10 ` Will Deacon 2021-06-16 10:10 ` Will Deacon 2021-06-15 19:18 ` Will Deacon 2021-06-15 19:18 ` Will Deacon
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=2a0b7f37-156a-775f-ade4-015cade472c6@huawei.com \ --to=thunder.leizhen@huawei.com \ --cc=iommu@lists.linux-foundation.org \ --cc=linux-arm-kernel@lists.infradead.org \ --cc=robin.murphy@arm.com \ --cc=will@kernel.org \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.