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Merge branch 'x86-cache-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 cache resource controller updates from Thomas Gleixner: "An update for the Intel Resource Director Technolgy (RDT) which adds a feedback driven software controller to runtime adjust the bandwidth allocation MSRs. This makes the allocations more accurate and allows to use bandwidth values in understandable units (MB/s) instead of using percentage based allocations as the original, still available, interface. The software controller can be enabled with a new mount option for the resctrl filesystem" * 'x86-cache-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/intel_rdt/mba_sc: Feedback loop to dynamically update mem bandwidth x86/intel_rdt/mba_sc: Prepare for feedback loop x86/intel_rdt/mba_sc: Add schemata support x86/intel_rdt/mba_sc: Add initialization support x86/intel_rdt/mba_sc: Enable/disable MBA software controller x86/intel_rdt/mba_sc: Documentation for MBA software controller(mba_sc)
This commit is contained in:
Linus Torvalds
commit
ab20fd0013
@ -17,12 +17,14 @@ MBA (Memory Bandwidth Allocation) - "mba"
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To use the feature mount the file system:
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# mount -t resctrl resctrl [-o cdp[,cdpl2]] /sys/fs/resctrl
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# mount -t resctrl resctrl [-o cdp[,cdpl2][,mba_MBps]] /sys/fs/resctrl
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mount options are:
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"cdp": Enable code/data prioritization in L3 cache allocations.
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"cdpl2": Enable code/data prioritization in L2 cache allocations.
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"mba_MBps": Enable the MBA Software Controller(mba_sc) to specify MBA
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bandwidth in MBps
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L2 and L3 CDP are controlled seperately.
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@ -270,10 +272,11 @@ and 0xA are not. On a system with a 20-bit mask each bit represents 5%
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of the capacity of the cache. You could partition the cache into four
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equal parts with masks: 0x1f, 0x3e0, 0x7c00, 0xf8000.
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Memory bandwidth(b/w) percentage
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--------------------------------
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For Memory b/w resource, user controls the resource by indicating the
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percentage of total memory b/w.
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Memory bandwidth Allocation and monitoring
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------------------------------------------
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For Memory bandwidth resource, by default the user controls the resource
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by indicating the percentage of total memory bandwidth.
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The minimum bandwidth percentage value for each cpu model is predefined
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and can be looked up through "info/MB/min_bandwidth". The bandwidth
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@ -285,7 +288,47 @@ to the next control step available on the hardware.
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The bandwidth throttling is a core specific mechanism on some of Intel
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SKUs. Using a high bandwidth and a low bandwidth setting on two threads
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sharing a core will result in both threads being throttled to use the
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low bandwidth.
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low bandwidth. The fact that Memory bandwidth allocation(MBA) is a core
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specific mechanism where as memory bandwidth monitoring(MBM) is done at
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the package level may lead to confusion when users try to apply control
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via the MBA and then monitor the bandwidth to see if the controls are
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effective. Below are such scenarios:
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1. User may *not* see increase in actual bandwidth when percentage
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values are increased:
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This can occur when aggregate L2 external bandwidth is more than L3
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external bandwidth. Consider an SKL SKU with 24 cores on a package and
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where L2 external is 10GBps (hence aggregate L2 external bandwidth is
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240GBps) and L3 external bandwidth is 100GBps. Now a workload with '20
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threads, having 50% bandwidth, each consuming 5GBps' consumes the max L3
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bandwidth of 100GBps although the percentage value specified is only 50%
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<< 100%. Hence increasing the bandwidth percentage will not yeild any
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more bandwidth. This is because although the L2 external bandwidth still
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has capacity, the L3 external bandwidth is fully used. Also note that
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this would be dependent on number of cores the benchmark is run on.
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2. Same bandwidth percentage may mean different actual bandwidth
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depending on # of threads:
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For the same SKU in #1, a 'single thread, with 10% bandwidth' and '4
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thread, with 10% bandwidth' can consume upto 10GBps and 40GBps although
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they have same percentage bandwidth of 10%. This is simply because as
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threads start using more cores in an rdtgroup, the actual bandwidth may
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increase or vary although user specified bandwidth percentage is same.
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In order to mitigate this and make the interface more user friendly,
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resctrl added support for specifying the bandwidth in MBps as well. The
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kernel underneath would use a software feedback mechanism or a "Software
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Controller(mba_sc)" which reads the actual bandwidth using MBM counters
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and adjust the memowy bandwidth percentages to ensure
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"actual bandwidth < user specified bandwidth".
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By default, the schemata would take the bandwidth percentage values
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where as user can switch to the "MBA software controller" mode using
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a mount option 'mba_MBps'. The schemata format is specified in the below
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sections.
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L3 schemata file details (code and data prioritization disabled)
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----------------------------------------------------------------
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@ -308,13 +351,20 @@ schemata format is always:
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L2:<cache_id0>=<cbm>;<cache_id1>=<cbm>;...
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Memory b/w Allocation details
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-----------------------------
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Memory bandwidth Allocation (default mode)
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------------------------------------------
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Memory b/w domain is L3 cache.
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MB:<cache_id0>=bandwidth0;<cache_id1>=bandwidth1;...
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Memory bandwidth Allocation specified in MBps
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---------------------------------------------
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Memory bandwidth domain is L3 cache.
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MB:<cache_id0>=bw_MBps0;<cache_id1>=bw_MBps1;...
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Reading/writing the schemata file
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---------------------------------
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Reading the schemata file will show the state of all resources
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@ -358,6 +408,15 @@ allocations can overlap or not. The allocations specifies the maximum
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b/w that the group may be able to use and the system admin can configure
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the b/w accordingly.
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If the MBA is specified in MB(megabytes) then user can enter the max b/w in MB
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rather than the percentage values.
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# echo "L3:0=3;1=c\nMB:0=1024;1=500" > /sys/fs/resctrl/p0/schemata
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# echo "L3:0=3;1=3\nMB:0=1024;1=500" > /sys/fs/resctrl/p1/schemata
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In the above example the tasks in "p1" and "p0" on socket 0 would use a max b/w
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of 1024MB where as on socket 1 they would use 500MB.
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Example 2
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---------
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Again two sockets, but this time with a more realistic 20-bit mask.
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@ -33,8 +33,8 @@
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#include <asm/intel_rdt_sched.h>
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#include "intel_rdt.h"
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#define MAX_MBA_BW 100u
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#define MBA_IS_LINEAR 0x4
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#define MBA_MAX_MBPS U32_MAX
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/* Mutex to protect rdtgroup access. */
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DEFINE_MUTEX(rdtgroup_mutex);
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@ -178,7 +178,7 @@ struct rdt_resource rdt_resources_all[] = {
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.msr_update = mba_wrmsr,
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.cache_level = 3,
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.parse_ctrlval = parse_bw,
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.format_str = "%d=%*d",
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.format_str = "%d=%*u",
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.fflags = RFTYPE_RES_MB,
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},
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};
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@ -230,6 +230,14 @@ static inline void cache_alloc_hsw_probe(void)
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rdt_alloc_capable = true;
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}
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bool is_mba_sc(struct rdt_resource *r)
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{
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if (!r)
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return rdt_resources_all[RDT_RESOURCE_MBA].membw.mba_sc;
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return r->membw.mba_sc;
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}
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/*
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* rdt_get_mb_table() - get a mapping of bandwidth(b/w) percentage values
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* exposed to user interface and the h/w understandable delay values.
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@ -341,7 +349,7 @@ static int get_cache_id(int cpu, int level)
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* that can be written to QOS_MSRs.
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* There are currently no SKUs which support non linear delay values.
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*/
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static u32 delay_bw_map(unsigned long bw, struct rdt_resource *r)
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u32 delay_bw_map(unsigned long bw, struct rdt_resource *r)
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{
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if (r->membw.delay_linear)
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return MAX_MBA_BW - bw;
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@ -431,25 +439,40 @@ struct rdt_domain *rdt_find_domain(struct rdt_resource *r, int id,
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return NULL;
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}
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void setup_default_ctrlval(struct rdt_resource *r, u32 *dc, u32 *dm)
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{
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int i;
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/*
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* Initialize the Control MSRs to having no control.
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* For Cache Allocation: Set all bits in cbm
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* For Memory Allocation: Set b/w requested to 100%
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* and the bandwidth in MBps to U32_MAX
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*/
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for (i = 0; i < r->num_closid; i++, dc++, dm++) {
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*dc = r->default_ctrl;
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*dm = MBA_MAX_MBPS;
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}
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}
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static int domain_setup_ctrlval(struct rdt_resource *r, struct rdt_domain *d)
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{
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struct msr_param m;
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u32 *dc;
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int i;
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u32 *dc, *dm;
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dc = kmalloc_array(r->num_closid, sizeof(*d->ctrl_val), GFP_KERNEL);
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if (!dc)
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return -ENOMEM;
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d->ctrl_val = dc;
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dm = kmalloc_array(r->num_closid, sizeof(*d->mbps_val), GFP_KERNEL);
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if (!dm) {
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kfree(dc);
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return -ENOMEM;
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}
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/*
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* Initialize the Control MSRs to having no control.
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* For Cache Allocation: Set all bits in cbm
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* For Memory Allocation: Set b/w requested to 100
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*/
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for (i = 0; i < r->num_closid; i++, dc++)
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*dc = r->default_ctrl;
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d->ctrl_val = dc;
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d->mbps_val = dm;
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setup_default_ctrlval(r, dc, dm);
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m.low = 0;
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m.high = r->num_closid;
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@ -588,6 +611,7 @@ static void domain_remove_cpu(int cpu, struct rdt_resource *r)
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}
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kfree(d->ctrl_val);
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kfree(d->mbps_val);
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kfree(d->rmid_busy_llc);
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kfree(d->mbm_total);
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kfree(d->mbm_local);
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@ -28,6 +28,7 @@
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#define MBM_CNTR_WIDTH 24
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#define MBM_OVERFLOW_INTERVAL 1000
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#define MAX_MBA_BW 100u
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#define RMID_VAL_ERROR BIT_ULL(63)
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#define RMID_VAL_UNAVAIL BIT_ULL(62)
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@ -180,10 +181,20 @@ struct rftype {
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* struct mbm_state - status for each MBM counter in each domain
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* @chunks: Total data moved (multiply by rdt_group.mon_scale to get bytes)
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* @prev_msr Value of IA32_QM_CTR for this RMID last time we read it
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* @chunks_bw Total local data moved. Used for bandwidth calculation
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* @prev_bw_msr:Value of previous IA32_QM_CTR for bandwidth counting
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* @prev_bw The most recent bandwidth in MBps
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* @delta_bw Difference between the current and previous bandwidth
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* @delta_comp Indicates whether to compute the delta_bw
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*/
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struct mbm_state {
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u64 chunks;
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u64 prev_msr;
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u64 chunks_bw;
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u64 prev_bw_msr;
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u32 prev_bw;
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u32 delta_bw;
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bool delta_comp;
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};
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/**
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@ -202,6 +213,7 @@ struct mbm_state {
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* @cqm_work_cpu:
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* worker cpu for CQM h/w counters
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* @ctrl_val: array of cache or mem ctrl values (indexed by CLOSID)
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* @mbps_val: When mba_sc is enabled, this holds the bandwidth in MBps
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* @new_ctrl: new ctrl value to be loaded
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* @have_new_ctrl: did user provide new_ctrl for this domain
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*/
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@ -217,6 +229,7 @@ struct rdt_domain {
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int mbm_work_cpu;
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int cqm_work_cpu;
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u32 *ctrl_val;
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u32 *mbps_val;
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u32 new_ctrl;
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bool have_new_ctrl;
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};
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@ -259,6 +272,7 @@ struct rdt_cache {
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* @min_bw: Minimum memory bandwidth percentage user can request
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* @bw_gran: Granularity at which the memory bandwidth is allocated
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* @delay_linear: True if memory B/W delay is in linear scale
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* @mba_sc: True if MBA software controller(mba_sc) is enabled
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* @mb_map: Mapping of memory B/W percentage to memory B/W delay
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*/
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struct rdt_membw {
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@ -266,6 +280,7 @@ struct rdt_membw {
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u32 min_bw;
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u32 bw_gran;
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u32 delay_linear;
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bool mba_sc;
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u32 *mb_map;
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};
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@ -445,6 +460,9 @@ void mon_event_read(struct rmid_read *rr, struct rdt_domain *d,
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void mbm_setup_overflow_handler(struct rdt_domain *dom,
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unsigned long delay_ms);
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void mbm_handle_overflow(struct work_struct *work);
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bool is_mba_sc(struct rdt_resource *r);
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void setup_default_ctrlval(struct rdt_resource *r, u32 *dc, u32 *dm);
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u32 delay_bw_map(unsigned long bw, struct rdt_resource *r);
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void cqm_setup_limbo_handler(struct rdt_domain *dom, unsigned long delay_ms);
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void cqm_handle_limbo(struct work_struct *work);
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bool has_busy_rmid(struct rdt_resource *r, struct rdt_domain *d);
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@ -53,7 +53,8 @@ static bool bw_validate(char *buf, unsigned long *data, struct rdt_resource *r)
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return false;
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}
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if (bw < r->membw.min_bw || bw > r->default_ctrl) {
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if ((bw < r->membw.min_bw || bw > r->default_ctrl) &&
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!is_mba_sc(r)) {
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rdt_last_cmd_printf("MB value %ld out of range [%d,%d]\n", bw,
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r->membw.min_bw, r->default_ctrl);
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return false;
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@ -179,6 +180,8 @@ static int update_domains(struct rdt_resource *r, int closid)
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struct msr_param msr_param;
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cpumask_var_t cpu_mask;
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struct rdt_domain *d;
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bool mba_sc;
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u32 *dc;
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int cpu;
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if (!zalloc_cpumask_var(&cpu_mask, GFP_KERNEL))
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@ -188,13 +191,20 @@ static int update_domains(struct rdt_resource *r, int closid)
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msr_param.high = msr_param.low + 1;
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msr_param.res = r;
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|
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mba_sc = is_mba_sc(r);
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list_for_each_entry(d, &r->domains, list) {
|
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if (d->have_new_ctrl && d->new_ctrl != d->ctrl_val[closid]) {
|
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dc = !mba_sc ? d->ctrl_val : d->mbps_val;
|
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if (d->have_new_ctrl && d->new_ctrl != dc[closid]) {
|
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cpumask_set_cpu(cpumask_any(&d->cpu_mask), cpu_mask);
|
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d->ctrl_val[closid] = d->new_ctrl;
|
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dc[closid] = d->new_ctrl;
|
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}
|
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}
|
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if (cpumask_empty(cpu_mask))
|
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|
||||
/*
|
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* Avoid writing the control msr with control values when
|
||||
* MBA software controller is enabled
|
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*/
|
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if (cpumask_empty(cpu_mask) || mba_sc)
|
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goto done;
|
||||
cpu = get_cpu();
|
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/* Update CBM on this cpu if it's in cpu_mask. */
|
||||
@ -282,13 +292,17 @@ static void show_doms(struct seq_file *s, struct rdt_resource *r, int closid)
|
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{
|
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struct rdt_domain *dom;
|
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bool sep = false;
|
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u32 ctrl_val;
|
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|
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seq_printf(s, "%*s:", max_name_width, r->name);
|
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list_for_each_entry(dom, &r->domains, list) {
|
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if (sep)
|
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seq_puts(s, ";");
|
||||
|
||||
ctrl_val = (!is_mba_sc(r) ? dom->ctrl_val[closid] :
|
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dom->mbps_val[closid]);
|
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seq_printf(s, r->format_str, dom->id, max_data_width,
|
||||
dom->ctrl_val[closid]);
|
||||
ctrl_val);
|
||||
sep = true;
|
||||
}
|
||||
seq_puts(s, "\n");
|
||||
|
||||
@ -225,10 +225,18 @@ void free_rmid(u32 rmid)
|
||||
list_add_tail(&entry->list, &rmid_free_lru);
|
||||
}
|
||||
|
||||
static u64 mbm_overflow_count(u64 prev_msr, u64 cur_msr)
|
||||
{
|
||||
u64 shift = 64 - MBM_CNTR_WIDTH, chunks;
|
||||
|
||||
chunks = (cur_msr << shift) - (prev_msr << shift);
|
||||
return chunks >>= shift;
|
||||
}
|
||||
|
||||
static int __mon_event_count(u32 rmid, struct rmid_read *rr)
|
||||
{
|
||||
u64 chunks, shift, tval;
|
||||
struct mbm_state *m;
|
||||
u64 chunks, tval;
|
||||
|
||||
tval = __rmid_read(rmid, rr->evtid);
|
||||
if (tval & (RMID_VAL_ERROR | RMID_VAL_UNAVAIL)) {
|
||||
@ -254,14 +262,12 @@ static int __mon_event_count(u32 rmid, struct rmid_read *rr)
|
||||
}
|
||||
|
||||
if (rr->first) {
|
||||
m->prev_msr = tval;
|
||||
m->chunks = 0;
|
||||
memset(m, 0, sizeof(struct mbm_state));
|
||||
m->prev_bw_msr = m->prev_msr = tval;
|
||||
return 0;
|
||||
}
|
||||
|
||||
shift = 64 - MBM_CNTR_WIDTH;
|
||||
chunks = (tval << shift) - (m->prev_msr << shift);
|
||||
chunks >>= shift;
|
||||
chunks = mbm_overflow_count(m->prev_msr, tval);
|
||||
m->chunks += chunks;
|
||||
m->prev_msr = tval;
|
||||
|
||||
@ -269,6 +275,32 @@ static int __mon_event_count(u32 rmid, struct rmid_read *rr)
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* Supporting function to calculate the memory bandwidth
|
||||
* and delta bandwidth in MBps.
|
||||
*/
|
||||
static void mbm_bw_count(u32 rmid, struct rmid_read *rr)
|
||||
{
|
||||
struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_L3];
|
||||
struct mbm_state *m = &rr->d->mbm_local[rmid];
|
||||
u64 tval, cur_bw, chunks;
|
||||
|
||||
tval = __rmid_read(rmid, rr->evtid);
|
||||
if (tval & (RMID_VAL_ERROR | RMID_VAL_UNAVAIL))
|
||||
return;
|
||||
|
||||
chunks = mbm_overflow_count(m->prev_bw_msr, tval);
|
||||
m->chunks_bw += chunks;
|
||||
m->chunks = m->chunks_bw;
|
||||
cur_bw = (chunks * r->mon_scale) >> 20;
|
||||
|
||||
if (m->delta_comp)
|
||||
m->delta_bw = abs(cur_bw - m->prev_bw);
|
||||
m->delta_comp = false;
|
||||
m->prev_bw = cur_bw;
|
||||
m->prev_bw_msr = tval;
|
||||
}
|
||||
|
||||
/*
|
||||
* This is called via IPI to read the CQM/MBM counters
|
||||
* on a domain.
|
||||
@ -297,6 +329,118 @@ void mon_event_count(void *info)
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
* Feedback loop for MBA software controller (mba_sc)
|
||||
*
|
||||
* mba_sc is a feedback loop where we periodically read MBM counters and
|
||||
* adjust the bandwidth percentage values via the IA32_MBA_THRTL_MSRs so
|
||||
* that:
|
||||
*
|
||||
* current bandwdith(cur_bw) < user specified bandwidth(user_bw)
|
||||
*
|
||||
* This uses the MBM counters to measure the bandwidth and MBA throttle
|
||||
* MSRs to control the bandwidth for a particular rdtgrp. It builds on the
|
||||
* fact that resctrl rdtgroups have both monitoring and control.
|
||||
*
|
||||
* The frequency of the checks is 1s and we just tag along the MBM overflow
|
||||
* timer. Having 1s interval makes the calculation of bandwidth simpler.
|
||||
*
|
||||
* Although MBA's goal is to restrict the bandwidth to a maximum, there may
|
||||
* be a need to increase the bandwidth to avoid uncecessarily restricting
|
||||
* the L2 <-> L3 traffic.
|
||||
*
|
||||
* Since MBA controls the L2 external bandwidth where as MBM measures the
|
||||
* L3 external bandwidth the following sequence could lead to such a
|
||||
* situation.
|
||||
*
|
||||
* Consider an rdtgroup which had high L3 <-> memory traffic in initial
|
||||
* phases -> mba_sc kicks in and reduced bandwidth percentage values -> but
|
||||
* after some time rdtgroup has mostly L2 <-> L3 traffic.
|
||||
*
|
||||
* In this case we may restrict the rdtgroup's L2 <-> L3 traffic as its
|
||||
* throttle MSRs already have low percentage values. To avoid
|
||||
* unnecessarily restricting such rdtgroups, we also increase the bandwidth.
|
||||
*/
|
||||
static void update_mba_bw(struct rdtgroup *rgrp, struct rdt_domain *dom_mbm)
|
||||
{
|
||||
u32 closid, rmid, cur_msr, cur_msr_val, new_msr_val;
|
||||
struct mbm_state *pmbm_data, *cmbm_data;
|
||||
u32 cur_bw, delta_bw, user_bw;
|
||||
struct rdt_resource *r_mba;
|
||||
struct rdt_domain *dom_mba;
|
||||
struct list_head *head;
|
||||
struct rdtgroup *entry;
|
||||
|
||||
r_mba = &rdt_resources_all[RDT_RESOURCE_MBA];
|
||||
closid = rgrp->closid;
|
||||
rmid = rgrp->mon.rmid;
|
||||
pmbm_data = &dom_mbm->mbm_local[rmid];
|
||||
|
||||
dom_mba = get_domain_from_cpu(smp_processor_id(), r_mba);
|
||||
if (!dom_mba) {
|
||||
pr_warn_once("Failure to get domain for MBA update\n");
|
||||
return;
|
||||
}
|
||||
|
||||
cur_bw = pmbm_data->prev_bw;
|
||||
user_bw = dom_mba->mbps_val[closid];
|
||||
delta_bw = pmbm_data->delta_bw;
|
||||
cur_msr_val = dom_mba->ctrl_val[closid];
|
||||
|
||||
/*
|
||||
* For Ctrl groups read data from child monitor groups.
|
||||
*/
|
||||
head = &rgrp->mon.crdtgrp_list;
|
||||
list_for_each_entry(entry, head, mon.crdtgrp_list) {
|
||||
cmbm_data = &dom_mbm->mbm_local[entry->mon.rmid];
|
||||
cur_bw += cmbm_data->prev_bw;
|
||||
delta_bw += cmbm_data->delta_bw;
|
||||
}
|
||||
|
||||
/*
|
||||
* Scale up/down the bandwidth linearly for the ctrl group. The
|
||||
* bandwidth step is the bandwidth granularity specified by the
|
||||
* hardware.
|
||||
*
|
||||
* The delta_bw is used when increasing the bandwidth so that we
|
||||
* dont alternately increase and decrease the control values
|
||||
* continuously.
|
||||
*
|
||||
* For ex: consider cur_bw = 90MBps, user_bw = 100MBps and if
|
||||
* bandwidth step is 20MBps(> user_bw - cur_bw), we would keep
|
||||
* switching between 90 and 110 continuously if we only check
|
||||
* cur_bw < user_bw.
|
||||
*/
|
||||
if (cur_msr_val > r_mba->membw.min_bw && user_bw < cur_bw) {
|
||||
new_msr_val = cur_msr_val - r_mba->membw.bw_gran;
|
||||
} else if (cur_msr_val < MAX_MBA_BW &&
|
||||
(user_bw > (cur_bw + delta_bw))) {
|
||||
new_msr_val = cur_msr_val + r_mba->membw.bw_gran;
|
||||
} else {
|
||||
return;
|
||||
}
|
||||
|
||||
cur_msr = r_mba->msr_base + closid;
|
||||
wrmsrl(cur_msr, delay_bw_map(new_msr_val, r_mba));
|
||||
dom_mba->ctrl_val[closid] = new_msr_val;
|
||||
|
||||
/*
|
||||
* Delta values are updated dynamically package wise for each
|
||||
* rdtgrp everytime the throttle MSR changes value.
|
||||
*
|
||||
* This is because (1)the increase in bandwidth is not perfectly
|
||||
* linear and only "approximately" linear even when the hardware
|
||||
* says it is linear.(2)Also since MBA is a core specific
|
||||
* mechanism, the delta values vary based on number of cores used
|
||||
* by the rdtgrp.
|
||||
*/
|
||||
pmbm_data->delta_comp = true;
|
||||
list_for_each_entry(entry, head, mon.crdtgrp_list) {
|
||||
cmbm_data = &dom_mbm->mbm_local[entry->mon.rmid];
|
||||
cmbm_data->delta_comp = true;
|
||||
}
|
||||
}
|
||||
|
||||
static void mbm_update(struct rdt_domain *d, int rmid)
|
||||
{
|
||||
struct rmid_read rr;
|
||||
@ -314,7 +458,16 @@ static void mbm_update(struct rdt_domain *d, int rmid)
|
||||
}
|
||||
if (is_mbm_local_enabled()) {
|
||||
rr.evtid = QOS_L3_MBM_LOCAL_EVENT_ID;
|
||||
__mon_event_count(rmid, &rr);
|
||||
|
||||
/*
|
||||
* Call the MBA software controller only for the
|
||||
* control groups and when user has enabled
|
||||
* the software controller explicitly.
|
||||
*/
|
||||
if (!is_mba_sc(NULL))
|
||||
__mon_event_count(rmid, &rr);
|
||||
else
|
||||
mbm_bw_count(rmid, &rr);
|
||||
}
|
||||
}
|
||||
|
||||
@ -385,6 +538,9 @@ void mbm_handle_overflow(struct work_struct *work)
|
||||
head = &prgrp->mon.crdtgrp_list;
|
||||
list_for_each_entry(crgrp, head, mon.crdtgrp_list)
|
||||
mbm_update(d, crgrp->mon.rmid);
|
||||
|
||||
if (is_mba_sc(NULL))
|
||||
update_mba_bw(prgrp, d);
|
||||
}
|
||||
|
||||
schedule_delayed_work_on(cpu, &d->mbm_over, delay);
|
||||
|
||||
@ -1005,6 +1005,11 @@ static void l2_qos_cfg_update(void *arg)
|
||||
wrmsrl(IA32_L2_QOS_CFG, *enable ? L2_QOS_CDP_ENABLE : 0ULL);
|
||||
}
|
||||
|
||||
static inline bool is_mba_linear(void)
|
||||
{
|
||||
return rdt_resources_all[RDT_RESOURCE_MBA].membw.delay_linear;
|
||||
}
|
||||
|
||||
static int set_cache_qos_cfg(int level, bool enable)
|
||||
{
|
||||
void (*update)(void *arg);
|
||||
@ -1041,6 +1046,28 @@ static int set_cache_qos_cfg(int level, bool enable)
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* Enable or disable the MBA software controller
|
||||
* which helps user specify bandwidth in MBps.
|
||||
* MBA software controller is supported only if
|
||||
* MBM is supported and MBA is in linear scale.
|
||||
*/
|
||||
static int set_mba_sc(bool mba_sc)
|
||||
{
|
||||
struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_MBA];
|
||||
struct rdt_domain *d;
|
||||
|
||||
if (!is_mbm_enabled() || !is_mba_linear() ||
|
||||
mba_sc == is_mba_sc(r))
|
||||
return -EINVAL;
|
||||
|
||||
r->membw.mba_sc = mba_sc;
|
||||
list_for_each_entry(d, &r->domains, list)
|
||||
setup_default_ctrlval(r, d->ctrl_val, d->mbps_val);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int cdp_enable(int level, int data_type, int code_type)
|
||||
{
|
||||
struct rdt_resource *r_ldata = &rdt_resources_all[data_type];
|
||||
@ -1123,6 +1150,10 @@ static int parse_rdtgroupfs_options(char *data)
|
||||
ret = cdpl2_enable();
|
||||
if (ret)
|
||||
goto out;
|
||||
} else if (!strcmp(token, "mba_MBps")) {
|
||||
ret = set_mba_sc(true);
|
||||
if (ret)
|
||||
goto out;
|
||||
} else {
|
||||
ret = -EINVAL;
|
||||
goto out;
|
||||
@ -1445,6 +1476,8 @@ static void rdt_kill_sb(struct super_block *sb)
|
||||
cpus_read_lock();
|
||||
mutex_lock(&rdtgroup_mutex);
|
||||
|
||||
set_mba_sc(false);
|
||||
|
||||
/*Put everything back to default values. */
|
||||
for_each_alloc_enabled_rdt_resource(r)
|
||||
reset_all_ctrls(r);
|
||||
|
||||
Loading…
Reference in New Issue
Block a user