gecko-dev/xpcom/base/nsIMemoryReporter.idl

652 строки
25 KiB
Plaintext

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "nsISupports.idl"
interface nsIDOMWindow;
interface nsIRunnable;
interface nsISimpleEnumerator;
/*
* Memory reporters measure Firefox's memory usage. They are primarily used to
* generate the about:memory page. You should read
* https://wiki.mozilla.org/Memory_Reporting before writing a memory
* reporter.
*/
[scriptable, function, uuid(3a61be3b-b93b-461a-a4f8-388214f558b1)]
interface nsIMemoryReporterCallback : nsISupports
{
/*
* The arguments to the callback are as follows.
*
*
* |process| The name of the process containing this reporter. Each
* reporter initially has "" in this field, indicating that it applies to the
* current process. (This is true even for reporters in a child process.)
* When a reporter from a child process is copied into the main process, the
* copy has its 'process' field set appropriately.
*
*
* |path| The path that this memory usage should be reported under. Paths
* are '/'-delimited, eg. "a/b/c".
*
* Each reporter can be viewed as representing a leaf node in a tree.
* Internal nodes of the tree don't have reporters. So, for example, the
* reporters "explicit/a/b", "explicit/a/c", "explicit/d/e", and
* "explicit/d/f" define this tree:
*
* explicit
* |--a
* | |--b [*]
* | \--c [*]
* \--d
* |--e [*]
* \--f [*]
*
* Nodes marked with a [*] have a reporter. Notice that the internal
* nodes are implicitly defined by the paths.
*
* Nodes within a tree should not overlap measurements, otherwise the
* parent node measurements will be double-counted. So in the example
* above, |b| should not count any allocations counted by |c|, and vice
* versa.
*
* All nodes within each tree must have the same units.
*
* If you want to include a '/' not as a path separator, e.g. because the
* path contains a URL, you need to convert each '/' in the URL to a '\'.
* Consumers of the path will undo this change. Any other '\' character
* in a path will also be changed. This is clumsy but hasn't caused any
* problems so far.
*
* The paths of all reporters form a set of trees. Trees can be
* "degenerate", i.e. contain a single entry with no '/'.
*
*
* |kind| There are three kinds of memory reporters.
*
* - HEAP: reporters measuring memory allocated by the heap allocator,
* e.g. by calling malloc, calloc, realloc, memalign, operator new, or
* operator new[]. Reporters in this category must have units
* UNITS_BYTES.
*
* - NONHEAP: reporters measuring memory which the program explicitly
* allocated, but does not live on the heap. Such memory is commonly
* allocated by calling one of the OS's memory-mapping functions (e.g.
* mmap, VirtualAlloc, or vm_allocate). Reporters in this category
* must have units UNITS_BYTES.
*
* - OTHER: reporters which don't fit into either of these categories.
* They can have any units.
*
* The kind only matters for reporters in the "explicit" tree;
* aboutMemory.js uses it to calculate "heap-unclassified".
*
*
* |units| The units on the reporter's amount. One of the following.
*
* - BYTES: The amount contains a number of bytes.
*
* - COUNT: The amount is an instantaneous count of things currently in
* existence. For instance, the number of tabs currently open would have
* units COUNT.
*
* - COUNT_CUMULATIVE: The amount contains the number of times some event
* has occurred since the application started up. For instance, the
* number of times the user has opened a new tab would have units
* COUNT_CUMULATIVE.
*
* The amount returned by a reporter with units COUNT_CUMULATIVE must
* never decrease over the lifetime of the application.
*
* - PERCENTAGE: The amount contains a fraction that should be expressed as
* a percentage. NOTE! The |amount| field should be given a value 100x
* the actual percentage; this number will be divided by 100 when shown.
* This allows a fractional percentage to be shown even though |amount| is
* an integer. E.g. if the actual percentage is 12.34%, |amount| should
* be 1234.
*
* Values greater than 100% are allowed.
*
*
* |amount| The numeric value reported by this memory reporter. Accesses
* can fail if something goes wrong when getting the amount.
*
*
* |description| A human-readable description of this memory usage report.
*/
void callback(in ACString process, in AUTF8String path, in int32_t kind,
in int32_t units, in int64_t amount,
in AUTF8String description, in nsISupports data);
};
/*
* An nsIMemoryReporter reports one or more memory measurements via a
* callback function which is called once for each measurement.
*
* An nsIMemoryReporter that reports a single measurement is sometimes called a
* "uni-reporter". One that reports multiple measurements is sometimes called
* a "multi-reporter".
*
* aboutMemory.js is the most important consumer of memory reports. It
* places the following constraints on reports.
*
* - All reports within a single sub-tree must have the same units.
*
* - There may be an "explicit" tree. If present, it represents
* non-overlapping regions of memory that have been explicitly allocated with
* an OS-level allocation (e.g. mmap/VirtualAlloc/vm_allocate) or a
* heap-level allocation (e.g. malloc/calloc/operator new). Reporters in
* this tree must have kind HEAP or NONHEAP, units BYTES.
*
* It is preferred, but not required, that report descriptions use complete
* sentences (i.e. start with a capital letter and end with a period, or
* similar).
*/
[scriptable, uuid(0884cd0f-5829-4381-979b-0f53904030ed)]
interface nsIMemoryReporter : nsISupports
{
/*
* Run the reporter.
*/
void collectReports(in nsIMemoryReporterCallback callback,
in nsISupports data);
/*
* Kinds. See the |kind| comment in nsIMemoryReporterCallback.
*/
const int32_t KIND_NONHEAP = 0;
const int32_t KIND_HEAP = 1;
const int32_t KIND_OTHER = 2;
/*
* Units. See the |units| comment in nsIMemoryReporterCallback.
*/
const int32_t UNITS_BYTES = 0;
const int32_t UNITS_COUNT = 1;
const int32_t UNITS_COUNT_CUMULATIVE = 2;
const int32_t UNITS_PERCENTAGE = 3;
};
[scriptable, function, uuid(548b3909-c04d-4ca6-8466-b8bee3837457)]
interface nsIFinishReportingCallback : nsISupports
{
void callback(in nsISupports data);
};
[scriptable, builtinclass, uuid(b6e5ec8a-71d9-48db-8ae9-68b4c5bbf2c3)]
interface nsIMemoryReporterManager : nsISupports
{
/*
* Initialize.
*/
void init();
/*
* Register the given nsIMemoryReporter. The Manager service will hold a
* strong reference to the given reporter, and will be responsible for freeing
* the reporter at shutdown. You may manually unregister the reporter with
* unregisterStrongReporter() at any point.
*/
void registerStrongReporter(in nsIMemoryReporter reporter);
/*
* Like registerReporter, but the Manager service will hold a weak reference
* via a raw pointer to the given reporter. The reporter should be
* unregistered before shutdown.
* You cannot register JavaScript components with this function! Always
* register your JavaScript components with registerStrongReporter().
*/
void registerWeakReporter(in nsIMemoryReporter reporter);
/*
* Unregister the given memory reporter, which must have been registered with
* registerStrongReporter(). You normally don't need to unregister your
* strong reporters, as nsIMemoryReporterManager will take care of that at
* shutdown.
*/
void unregisterStrongReporter(in nsIMemoryReporter reporter);
/*
* Unregister the given memory reporter, which must have been registered with
* registerWeakReporter().
*/
void unregisterWeakReporter(in nsIMemoryReporter reporter);
/*
* These functions should only be used for testing purposes.
*/
void blockRegistrationAndHideExistingReporters();
void unblockRegistrationAndRestoreOriginalReporters();
void registerStrongReporterEvenIfBlocked(in nsIMemoryReporter aReporter);
/*
* Get memory reports for the current process and all child processes.
* |handleReport| is called for each report, and |finishReporting| is called
* once all reports have been handled.
*
* |finishReporting| is called even if, for example, some child processes
* fail to report back. However, calls to this method will silently and
* immediately abort -- and |finishReporting| will not be called -- if a
* previous getReports() call is still in flight, i.e. if it has not yet
* finished invoking |finishReporting|. The silent abort is because the
* in-flight request will finish soon, and the caller would very likely just
* catch and ignore any error anyway.
*/
void getReports(in nsIMemoryReporterCallback handleReport,
in nsISupports handleReportData,
in nsIFinishReportingCallback finishReporting,
in nsISupports finishReportingData);
/*
* As above, but: If |minimizeMemoryUsage| is true, then each process will
* minimize its memory usage (see the |minimizeMemoryUsage| method) before
* gathering its report. If DMD is enabled and |DMDDumpIdent| is non-empty
* then write a DMD report to a file in the usual temporary directory (see
* |dumpMemoryInfoToTempDir| in |nsIMemoryInfoDumper|.)
*/
[noscript] void
getReportsExtended(in nsIMemoryReporterCallback handleReport,
in nsISupports handleReportData,
in nsIFinishReportingCallback finishReporting,
in nsISupports finishReportingData,
in boolean minimizeMemoryUsage,
in AString DMDDumpIdent);
/*
* Get memory reports in the current process only. |handleReport| is called
* for each report.
*/
void getReportsForThisProcess(in nsIMemoryReporterCallback handleReport,
in nsISupports handleReportData);
/*
* As above, but if DMD is enabled and |DMDDumpIdent| is non-empty
* then write a DMD report to a file in the usual temporary directory (see
* |dumpMemoryInfoToTempDir| in |nsIMemoryInfoDumper|.)
*/
[noscript] void
getReportsForThisProcessExtended(in nsIMemoryReporterCallback handleReport,
in nsISupports handleReportData,
in AString DMDDumpIdent);
/*
* The memory reporter manager, for the most part, treats reporters
* registered with it as a black box. However, there are some
* "distinguished" amounts (as could be reported by a memory reporter) that
* the manager provides as attributes, because they are sufficiently
* interesting that we want external code (e.g. telemetry) to be able to rely
* on them.
*
* Note that these are not reporters and so getReports() and
* getReportsForThisProcess() do not look at them. However, distinguished
* amounts can be embedded in a reporter.
*
* Access to these attributes can fail. In particular, some of them are not
* available on all platforms.
*
* If you add a new distinguished amount, please update
* toolkit/components/aboutmemory/tests/test_memoryReporters.xul.
*
* |explicit| (UNITS_BYTES) The total size of explicit memory allocations,
* both at the OS-level (eg. via mmap, VirtualAlloc) and at the heap level
* (eg. via malloc, calloc, operator new). It covers all heap allocations,
* but will miss any OS-level ones not covered by memory reporters.
*
* |vsize| (UNITS_BYTES) The virtual size, i.e. the amount of address space
* taken up.
*
* |vsizeMaxContiguous| (UNITS_BYTES) The size of the largest contiguous
* block of virtual memory.
*
* |resident| (UNITS_BYTES) The resident size (a.k.a. RSS or physical memory
* used).
*
* |residentFast| (UNITS_BYTES) This is like |resident|, but on Mac OS
* |resident| can purge pages, which is slow. It also affects the result of
* |residentFast|, and so |resident| and |residentFast| should not be used
* together.
*
* |heapAllocated| (UNITS_BYTES) Memory mapped by the heap allocator.
*
* |heapOverheadRatio| (UNITS_PERCENTAGE) In the heap allocator, this is the
* ratio of committed, unused bytes to allocated bytes. Like all
* UNITS_PERCENTAGE measurements, its amount is multiplied by 100x so it can
* be represented by an int64_t.
*
* |JSMainRuntimeGCHeap| (UNITS_BYTES) Size of the main JS runtime's GC
* heap.
*
* |JSMainRuntimeTemporaryPeak| (UNITS_BYTES) Peak size of the transient
* storage in the main JSRuntime.
*
* |JSMainRuntimeCompartments{System,User}| (UNITS_COUNT) The number of
* {system,user} compartments in the main JS runtime.
*
* |imagesContentUsedUncompressed| (UNITS_BYTES) Memory used for decoded
* raster images in content.
*
* |storageSQLite| (UNITS_BYTES) Memory used by SQLite.
*
* |lowMemoryEvents{Virtual,Physical}| (UNITS_COUNT_CUMULATIVE) The number
* of low-{virtual,physical}-memory events that have occurred since the
* process started.
*
* |ghostWindows| (UNITS_COUNT) The number of ghost windows.
*
* |pageFaultsHard| (UNITS_COUNT_CUMULATIVE) The number of hard (a.k.a.
* major) page faults that have occurred since the process started.
*/
readonly attribute int64_t explicit;
readonly attribute int64_t vsize;
readonly attribute int64_t vsizeMaxContiguous;
readonly attribute int64_t resident;
readonly attribute int64_t residentFast;
readonly attribute int64_t heapAllocated;
readonly attribute int64_t heapOverheadRatio;
readonly attribute int64_t JSMainRuntimeGCHeap;
readonly attribute int64_t JSMainRuntimeTemporaryPeak;
readonly attribute int64_t JSMainRuntimeCompartmentsSystem;
readonly attribute int64_t JSMainRuntimeCompartmentsUser;
readonly attribute int64_t imagesContentUsedUncompressed;
readonly attribute int64_t storageSQLite;
readonly attribute int64_t lowMemoryEventsVirtual;
readonly attribute int64_t lowMemoryEventsPhysical;
readonly attribute int64_t ghostWindows;
readonly attribute int64_t pageFaultsHard;
/*
* This attribute indicates if moz_malloc_usable_size() works.
*/
[infallible] readonly attribute boolean hasMozMallocUsableSize;
/*
* Run a series of GC/CC's in an attempt to minimize the application's memory
* usage. When we're finished, we invoke the given runnable if it's not
* null.
*/
void minimizeMemoryUsage(in nsIRunnable callback);
/*
* Measure the memory that is known to be owned by this tab, split up into
* several broad categories. Note that this will be an underestimate of the
* true number, due to imperfect memory reporter coverage (corresponding to
* about:memory's "heap-unclassified"), and due to some memory shared between
* tabs not being counted.
*
* The time taken for the measurement (split into JS and non-JS parts) is
* also returned.
*/
void sizeOfTab(in nsIDOMWindow window,
out int64_t jsObjectsSize, out int64_t jsStringsSize,
out int64_t jsOtherSize, out int64_t domSize,
out int64_t styleSize, out int64_t otherSize,
out int64_t totalSize,
out double jsMilliseconds, out double nonJSMilliseconds);
};
%{C++
#include "js/TypeDecls.h"
#include "nsStringGlue.h"
#include "nsTArray.h"
#include "mozilla/Atomics.h"
class nsPIDOMWindow;
// nsIHandleReportCallback is a better name, but keep nsIMemoryReporterCallback
// around for backwards compatibility.
typedef nsIMemoryReporterCallback nsIHandleReportCallback;
namespace mozilla {
// Register a memory reporter. The manager service will hold a strong
// reference to this reporter.
XPCOM_API(nsresult) RegisterStrongMemoryReporter(nsIMemoryReporter* aReporter);
// Register a memory reporter. The manager service will hold a weak reference
// to this reporter.
XPCOM_API(nsresult) RegisterWeakMemoryReporter(nsIMemoryReporter* aReporter);
// Unregister a weak memory reporter.
XPCOM_API(nsresult) UnregisterWeakMemoryReporter(nsIMemoryReporter* aReporter);
// The memory reporter manager provides access to several distinguished
// amounts via attributes. Some of these amounts are provided by Gecko
// components that cannot be accessed directly from XPCOM code. So we provide
// the following functions for those components to be registered with the
// manager.
typedef int64_t (*InfallibleAmountFn)();
typedef nsresult (*FallibleAmountFn)(int64_t* aAmount);
#define DECL_REGISTER_DISTINGUISHED_AMOUNT(kind, name) \
nsresult Register##name##DistinguishedAmount(kind##AmountFn aAmountFn);
#define DECL_UNREGISTER_DISTINGUISHED_AMOUNT(name) \
nsresult Unregister##name##DistinguishedAmount();
DECL_REGISTER_DISTINGUISHED_AMOUNT(Infallible, JSMainRuntimeGCHeap)
DECL_REGISTER_DISTINGUISHED_AMOUNT(Infallible, JSMainRuntimeTemporaryPeak)
DECL_REGISTER_DISTINGUISHED_AMOUNT(Infallible, JSMainRuntimeCompartmentsSystem)
DECL_REGISTER_DISTINGUISHED_AMOUNT(Infallible, JSMainRuntimeCompartmentsUser)
DECL_REGISTER_DISTINGUISHED_AMOUNT(Infallible, ImagesContentUsedUncompressed)
DECL_REGISTER_DISTINGUISHED_AMOUNT(Infallible, StorageSQLite)
DECL_UNREGISTER_DISTINGUISHED_AMOUNT(StorageSQLite)
DECL_REGISTER_DISTINGUISHED_AMOUNT(Infallible, LowMemoryEventsVirtual)
DECL_REGISTER_DISTINGUISHED_AMOUNT(Infallible, LowMemoryEventsPhysical)
DECL_REGISTER_DISTINGUISHED_AMOUNT(Infallible, GhostWindows)
#undef DECL_REGISTER_DISTINGUISHED_AMOUNT
#undef DECL_UNREGISTER_DISTINGUISHED_AMOUNT
// Likewise for per-tab measurement.
typedef nsresult (*JSSizeOfTabFn)(JSObject* aObj,
size_t* aJsObjectsSize,
size_t* aJsStringSize,
size_t* aJsPrivateSize,
size_t* aJsOtherSize);
typedef nsresult (*NonJSSizeOfTabFn)(nsPIDOMWindow* aWindow,
size_t* aDomSize,
size_t* aStyleSize,
size_t* aOtherSize);
nsresult RegisterJSSizeOfTab(JSSizeOfTabFn aSizeOfTabFn);
nsresult RegisterNonJSSizeOfTab(NonJSSizeOfTabFn aSizeOfTabFn);
}
#if defined(MOZ_DMD)
namespace mozilla {
namespace dmd {
// This runs all the memory reporters in the current process but does nothing
// with the results; i.e. it does the minimal amount of work possible for DMD
// to do its thing. It does nothing with child processes.
void RunReportersForThisProcess();
}
}
#if !defined(MOZ_MEMORY)
#error "MOZ_DMD requires MOZ_MEMORY"
#endif
#include "DMD.h"
#define MOZ_REPORT(ptr) mozilla::dmd::Report(ptr)
#define MOZ_REPORT_ON_ALLOC(ptr) mozilla::dmd::ReportOnAlloc(ptr)
#else
#define MOZ_REPORT(ptr)
#define MOZ_REPORT_ON_ALLOC(ptr)
#endif // defined(MOZ_DMD)
// Functions generated via this macro should be used by all traversal-based
// memory reporters. Such functions return |moz_malloc_size_of(ptr)|; this
// will always be zero on some obscure platforms.
//
// You might be wondering why we have a macro that creates multiple functions
// that differ only in their name, instead of a single MallocSizeOf function.
// It's mostly to help with DMD integration, though it sometimes also helps
// with debugging and temporary ad hoc profiling. The function name chosen
// doesn't matter greatly, but it's best to make it similar to the path used by
// the relevant memory reporter(s).
#define MOZ_DEFINE_MALLOC_SIZE_OF(fn) \
static size_t fn(const void* aPtr) \
{ \
MOZ_REPORT(aPtr); \
return moz_malloc_size_of(aPtr); \
}
// Functions generated by the next two macros should be used by wrapping
// allocators that report heap blocks as soon as they are allocated and
// unreport them as soon as they are freed. Such allocators are used in cases
// where we have third-party code that we cannot modify. The two functions
// must always be used in tandem.
#define MOZ_DEFINE_MALLOC_SIZE_OF_ON_ALLOC(fn) \
static size_t fn(const void* aPtr) \
{ \
MOZ_REPORT_ON_ALLOC(aPtr); \
return moz_malloc_size_of(aPtr); \
}
#define MOZ_DEFINE_MALLOC_SIZE_OF_ON_FREE(fn) \
static size_t fn(const void* aPtr) \
{ \
return moz_malloc_size_of(aPtr); \
}
namespace mozilla {
// This CRTP class handles several details of wrapping allocators and should
// be preferred to manually counting with MOZ_DEFINE_MALLOC_SIZE_OF_ON_ALLOC
// and MOZ_DEFINE_MALLOC_SIZE_OF_ON_FREE. The typical use is in a memory
// reporter for a particular third party library:
//
// class MyMemoryReporter : public CountingAllocatorBase<MyMemoryReporter>
// {
// ...
// NS_IMETHODIMP
// CollectReports(nsIHandleReportCallback* aHandleReport, nsISupports* aData)
// {
// return MOZ_COLLECT_REPORTER(
// "explicit/path/to/somewhere", KIND_HEAP, UNITS_BYTES,
// MemoryAllocated(),
// "A description of what we are reporting."
// }
// };
//
// ...somewhere later in the code...
// SetThirdPartyMemoryFunctions(MyMemoryReporter::CountingAlloc,
// MyMemoryReporter::CountingFree);
template<typename T>
class CountingAllocatorBase
{
public:
CountingAllocatorBase()
{
#ifdef DEBUG
// There must be only one instance of this class, due to |sAmount| being
// static.
static bool hasRun = false;
MOZ_ASSERT(!hasRun);
hasRun = true;
#endif
}
static size_t
MemoryAllocated()
{
return sAmount;
}
static void*
CountingMalloc(size_t size)
{
void* p = malloc(size);
sAmount += MallocSizeOfOnAlloc(p);
return p;
}
static void*
CountingCalloc(size_t nmemb, size_t size)
{
void* p = calloc(nmemb, size);
sAmount += MallocSizeOfOnAlloc(p);
return p;
}
static void*
CountingRealloc(void* p, size_t size)
{
size_t oldsize = MallocSizeOfOnFree(p);
void *pnew = realloc(p, size);
if (pnew) {
size_t newsize = MallocSizeOfOnAlloc(pnew);
sAmount += newsize - oldsize;
} else if (size == 0) {
// We asked for a 0-sized (re)allocation of some existing pointer
// and received NULL in return. 0-sized allocations are permitted
// to either return NULL or to allocate a unique object per call (!).
// For a malloc implementation that chooses the second strategy,
// that allocation may fail (unlikely, but possible).
//
// Given a NULL return value and an allocation size of 0, then, we
// don't know if that means the original pointer was freed or if
// the allocation of the unique object failed. If the original
// pointer was freed, then we have nothing to do here. If the
// allocation of the unique object failed, the original pointer is
// still valid and we ought to undo the decrement from above.
// However, we have no way of knowing how the underlying realloc
// implementation is behaving. Assuming that the original pointer
// was freed is the safest course of action. We do, however, need
// to note that we freed memory.
sAmount -= oldsize;
} else {
// realloc failed. The amount allocated hasn't changed.
}
return pnew;
}
static void
CountingFree(void* p)
{
sAmount -= MallocSizeOfOnFree(p);
free(p);
}
private:
// |sAmount| can be (implicitly) accessed by multiple threads, so it
// must be thread-safe.
static Atomic<size_t> sAmount;
MOZ_DEFINE_MALLOC_SIZE_OF_ON_ALLOC(MallocSizeOfOnAlloc)
MOZ_DEFINE_MALLOC_SIZE_OF_ON_FREE(MallocSizeOfOnFree)
};
}
// This macro assumes the presence of appropriate |aHandleReport| and |aData|
// variables.
#define MOZ_COLLECT_REPORT(path, kind, units, amount, description) \
aHandleReport->Callback(EmptyCString(), NS_LITERAL_CSTRING(path), \
kind, units, amount, \
NS_LITERAL_CSTRING(description), aData)
%}